Improvement in copper / tin / lead production

专利摘要:
What is disclosed is a diluted copper metal composition (11, 15) containing 57-85% by weight of Cu, ≥ 3.0% by weight of Ni, ≤ 0.8% by weight of Fe, 7-25% by weight of Sn and 3-15 % by weight of Pb comprises, together with a method which comprises partially oxidizing b) a composition of black copper (1) for obtaining a first copper refining slag (3) and a first enriched copper metal (4), partially oxidizing h ) the first enriched copper metal for obtaining a second copper refining slag (6), wherein at least 37.0% by weight of the amount of tin and lead is processed through steps b) and / or h) is recovered in the first and second copper refining slag together, partially reducing c) the first copper refining slag, forming a first lead-tin-based metal composition (13) and a first spent slag (12), adding the second copper-refining slag to the first lead-tin-based metal composition a first liquid bath (450) is formed d, partially oxidizing d) the first liquid bath, thereby obtaining the diluted copper metal composition (15).
公开号:BE1025772B1
申请号:E2018/5875
申请日:2018-12-10
公开日:2019-07-08
发明作者:Bert Coletti；Jan Dirk A. Goris；Visscher Yves De；Charles Geenen；Walter Guns；Niko Mollen；Steven Smets；Andy Breugelmans
申请人:Metallo Belgium；
IPC主号:

专利说明:

FIELD OF THE INVENTION
The present invention relates to the production of non-ferrous metals by pyrometallurgy, in particular the production of copper (Cu). More particularly, the invention relates to an improved process for the co-production of copper and solder currents from primary and secondary base materials, as high-quality products for further upgrading to metal products with commercially desired purities. Solder currents often belong to the family of metal compositions or alloys that contain significant amounts of tin (Sn), usually but not necessarily together with lead (Pb).
BACKGROUND OF THE INVENTION
The non-ferrous metals can be produced from new ores as the starting materials, also called primary sources, or from recyclable materials, also called secondary base materials, or from a combination thereof. Recyclable materials can for example be by-products, waste materials and materials at the end of their life. The recovery of non-ferrous metals from secondary base materials has, over the years, become an activity of the highest importance. The recycling of non-ferrous metals after use has come to play a key role in the industry, due to the continued high demand for such metals and the decreasing availability of new high-quality metal ores. Especially for the production of copper, its recovery from secondary base materials has acquired a considerable interest in the industry. In addition, the decreasing availability of new high-quality metal ores has also led to an increase in the importance of recovering non-ferrous metals from lower-quality metal base material. For example, the lower-grade metal base materials for copper recovery may contain significant amounts of other non-ferrous metals. These other metals may in themselves have significant potential commercial value, such as tin
BE2018 / 5875 and / or lead, but these primary and secondary base materials may contain other metals with a lower or no economic value at all, such as zinc, bismuth, antimony, arsenic or nickel. Often these other metals are undesirable in the high-quality non-ferrous metal products, or are only permissible at very limited levels.
The materials that are available as basic material for copper production therefore generally contain a multitude of metals. Secondary copper base materials are, for example, bronze, essentially an alloy of copper and tin, and brass, an alloy of primarily copper and zinc.
These different metals must be separated from the copper in the production process. The base materials may furthermore contain small amounts of a range of other elements, including iron, bismuth, antimony, arsenic, aluminum, manganese, sulfur, phosphorus and silicon, most of which are only permitted to a limited extent in a high-quality metal product.
Secondary basic materials that contain copper can also be electronic and / or electrical components at the end of their service life. In addition to copper, these basic materials generally contain the soldering components, mainly tin and lead, but usually also contain additional metals such as iron and aluminum, plus occasionally small quantities of precious metals, and also non-metallic parts such as plastics, paint, rubber, glue, wood , paper, cardboard etc .... These basic materials are generally not clean, and therefore usually also contain additional impurities such as dirt, grease, wax, soil and / or sand. Many metals in such base materials are often also partially oxidized.
Because the base materials with lower purities and higher levels of contaminants, both primary and secondary base materials, are much more widely available, there is a need to broaden the possibilities of non-ferrous metal production processes to increase the permissibility of such low-value raw materials as part of the base materials for the recovery or production of non-ferrous metals such as copper.
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The non-ferrous metal production processes generally comprise at least one, and usually a plurality of pyrometallurgical process steps. A very common first pyrometallurgical step for recovering copper from low-grade secondary materials is a smelting step. In a smelting furnace, the metals are melted, and organic substances and other combustible materials are removed by incineration. In addition, various chemical reactions take place between several of the other components that are introduced into the smelting furnace. Metals with a relatively high affinity for oxygen are converted to their oxides and collect in the supernatant slag phase with lower density. More volatile metals can escape from the liquid phase to the gas phase and leave the furnace with the exhaust gases, together with any carbon oxides and / or SO 2 that may have formed. The metals with a lower affinity for oxygen, if present in an oxidized state, rapidly reduce to their elemental metal form and move to the heavier underlying metal phase. If they are not oxidized, these metals remain present as elemental metal and remain in the bottom of the smelting furnace in the liquid metal phase with higher density. In a copper production step, the smelting step can be carried out in such a way that most of the iron ends up in the slag, while copper, tin and lead end up in the metal product, a stream commonly referred to as "black copper". Most of the nickel, antimony, arsenic and bismuth will also become part of the black copper product.
Patent DE 102012005401 A1 describes a process for the production of copper from secondary base materials, starting with a step for melting the raw materials. The melting step, according to the description, yielded a slag phase containing copper, tin, lead, and nickel. The slag was transferred to a rotary drum oven for further processing. This further processing consisted of a series of successive steps of partial chemical reduction, using carbon as a reducing agent, for successive recovery of specific metal products that each
BE2018 / 5875 are separated and removed from the oven. A first "prior" step ("Vorstufe") performed on the smelting furnace slag recovered a copper product for processing in an anode furnace ("A-metall"). In order to obtain copper of a sufficiently high quality, most of the tin and the lead, together with a considerable amount of copper, must remain in the slag phase. The slag from the Vorstufe was processed in a subsequent step 1 for producing a black copper product to be processed into granules, along with another remaining slag phase. Step 2 produced a crude mixed tin product from this slag phase, which was subsequently refined using silicon metal to produce a tin mixture and a silicon residue. The final step yielded a final slag, also for processing into grains. A problem with the method according to DE 102012005401 A1 is that the separations in steps 1 and 2, as well as those in the last step, are relatively weak, which leads to a weak global recovery of tin in the raw tin mixture, and consequently a relatively large loss of tin in the final slag, and also of lead, to the extent that lead would also be present.
U.S. Pat. No. 3,682,623, and its counterparts AU 505015 B2 and AU 469773 B2, describe a copper refining process that begins with a melting step leading to a black copper stream followed by the further stepwise pyrometallurgical refining of this black copper to a current of copper of anode quality, suitable for being cast into anodes for electrolytic refining. The refining of the black copper in US 3,682,623 led to the formation of a number of consecutive copper refiner slags, the early slag being rich in zinc, the middle slag rich in lead and tin, and the final slag rich in copper. The refined copper product had a purity of 98.70% by weight and contained 0.50% by weight of nickel (Table XII), together with 0.07% by weight of lead and the same amount of antimony. No information is provided on the remaining 0.66% by weight. This copper was cast into anodes for recovering the copper by electro refining. The different refining slags were collected and transferred as a single intermediate by-product from the copper refining to one
BE2018 / 5875 slag re-treatment furnace for recovering the copper, lead and tin present in those slags. In a first slag reprocessing step, the collected copper refiner slags were partially reduced by adding copper / iron scrap, copper / aluminum alloy and quicklime, so that a metal stream could be separated (Table XIV) with which about 90% of the copper and about 85% of the nickel was recovered in the oven. This tapped metal stream is referred to as "black copper" in US 3,682,623 and was recycled to the refining furnace, where it was mixed with the pre-refined black copper from the melting furnace and with radiators (Table VI). In the method of US 3,682,623, most of the nickel disappears from the process as an impurity in the anode copper. The amount of nickel present in the process according to US 3,682,623 is expected to increase with time, since 630 kg of nickel was recycled with the metal from Table XIV, while only 500 kg was present in the recycled black copper from the previous cycle in Table VI. After the black copper was drawn off, an extracted slag remained in the furnace, this slag being further reduced in a subsequent step by loading the furnace with an amount of 98% iron scrap. This second reduction step yielded a lead / tin metal (i.e., a kind of "crude solder") that was drained for further processing, along with an exhausted slag (Table XV), which was presumably disposed of. The solder metal product contained 3.00% by weight of iron, 13.54% by weight of copper and 1.57% by weight of nickel, i.e. 18.11% by weight in total.
The purity of the products in US 3,682,623 leaves something to be desired. The metals other than copper in the anode copper, and the metals other than tin and lead in the raw solder, represent a charge for the further processing of these product streams to obtain commercially valuable metal products. The anode copper in US 3,682,623 contained 1.30 wt% of impurities, of which 0.50 wt% was nickel. These impurities disrupt the electro-refining process, because copper in particular is deposited selectively on the cathode. The crude solder in US 3,682,623 contains 3.00% by weight of iron, 1.57% by weight of nickel and 13.54% by weight of copper, which form a burden on the process because these metals are a
BE2018 / 5875 cause considerable consumption of chemicals in the further refining of the solder, in particular if the solder refining is carried out as described in patent DE 102012005401 A1, i.e. by treatment with silicon metal, which is quite rare and therefore expensive.
Nickel is therefore a contaminant in both of the products of US 3,682,623. The method according to US 3,682,623 therefore has a strong incentive to limit the amount of nickel-containing base materials, for example as part of raw materials for the upstream melting unit. This reduces the acceptability of raw materials containing nickel in the process according to US 3,682,623, and of the more general operations of which it may form part.
Consequently, there remains a need for a pyrometallurgical process that provides higher purity copper and solder products from an operation to co-produce these metal products. In particular, there remains a need to achieve a better separation between copper in the anode copper on the one hand and the whole of tin and lead in the raw solder on the other. In addition, there is a need to allow more nickel into the process without this amount interfering with the downstream processing of the anode copper and / or the raw solder.
It is an object of the present invention to eliminate or at least alleviate the problem described above, and / or to provide improvements in general.
SUMMARY OF THE INVENTION
According to the invention there is provided a method as well as a diluted copper-containing stream as defined in any of the appended claims.
In one embodiment, the invention provides a diluted copper metal composition which comprises, by weight and in proportion to its total dry weight:
· At least 57% by weight and at most 85% by weight of copper,
BE2018 / 5875 · at least 3.0% by weight of nickel, • at most 0.8% by weight of iron, • at least 7% by weight and at most 25% by weight of tin, • at least 3% by weight and at least maximum 15% by weight of lead.
In one embodiment, the invention provides a method for preparing at least one diluted copper metal composition according to the present invention, the method comprising the steps of:
a) providing a black copper composition comprising at least 50% by weight of copper and at least 1.0% by weight of tin together with at least 1.0% by weight of lead,
b) partially oxidizing the black copper composition, thereby forming a first enriched copper metal phase and a first copper refining slag, followed by separating the first copper refining slag from the first enriched copper metal phase,
h) partially oxidizing the first enriched copper metal phase, thereby forming a second enriched copper metal phase and a second copper refining slag, followed by separating the second copper refining slag from the second enriched copper metal phase, wherein at least 37.0% by weight of the total amount of the tin and lead processed through process steps b) and / or h) is recovered in the first copper refining slag and the second copper refining slag together,
j) partially oxidizing the second enriched copper metal phase, thereby forming a third enriched copper metal phase and a third copper refining slag, followed by separating the third copper refining slag from the third enriched copper metal phase,
i) adding at least a portion of the second copper refining slag or of the third copper refining slag to a metal composition containing copper together with at least one soldering metal selected from tin and lead, thereby forming a first liquid bath, and
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d) partially oxidizing the first liquid bath, thereby forming a first diluted copper metal composition of the present invention and a first solder refining slag, followed by separating the first solder refining slag from the first diluted copper metal composition.
The applicants have found that the formation of the diluted copper metal composition according to the present invention offers a great advantage for obtaining a relatively clear separation between copper in a copper stream with high purity from the sequence of copper refining steps, possibly even up to anode quality, and a rough one soldering current on the other. The applicants have found that the copper in the two streams that are joined together in step i) quickly ends up as elemental copper in step d), and in step d) acts as an extractant for the tin and / or lead. The copper therefore acts as a support for the tin and / or the lead. It is therefore advantageous to carry part of the copper into steps corresponding to the corresponding slag phase in steps h) and / or j), since this first of all helps to remove more tin and / or lead from the main copper process stream that acts as a metal stream through the copper refining process steps b), h) and j) sets out to become a high-quality copper product stream that is sufficiently rich to be further processed into a high purity copper product.
Applicants have found that keeping the nickel content of the diluted copper metal composition of the present invention above the lower limit indicated has the advantage that more Ni can be removed from the process via process products other than the copper product with the highest purity of the process , ie the third enriched copper metal phase (anode quality). This feature further has the advantage that the global process is able to incorporate more nickel into its raw materials, without jeopardizing the quality of the copper product with the highest purity of the process. Maintaining the minimum nickel content as indicated further has the advantage that less nickel ends up in any of the first and second crude
BE2018 / 5875 solder metal composition, from which the nickel is preferably removed to allow their further processing and the recovery of high purity tin and / or lead products.
Applicants have determined that the concentration of iron in the diluted copper metal composition of the present invention should also meet the indicated upper limit. This entails the advantage that the further processing of the diluted copper metal composition according to the present invention is facilitated and encounters fewer operating problems, encounters fewer disposal problems, creates better separations, and can be made simpler and therefore less complicated. Iron leaves the process primarily as part of a spent snail, and it can present an explosion hazard when a molten liquid containing FeO, such as a spent snail, is quenched by direct contact with water. All the iron present in the diluted copper metal composition of the present invention is to be oxidized during the further processing of the composition. In many of the process steps where this is possible, it often leads to additional processing time and operating costs. In addition, a higher presence of iron in such a downstream process step increases the slag volume in that process step, and can have a negative effect on the balance at the end of that step between slag phase and metal phase. The production and / or presence of more slag volume in a particular process step also lowers the capacity, in that step and in downstream steps where the slag in question is further processed, to incorporate additional external base material.
Applicants have found that, thanks to the production of the first diluted copper metal composition according to the present invention as the metal phase, the oxidation step d) is able to produce a first solder refining slag richer in tin and / or lead, in particular tin and lead together, in proportion to the amount of copper entrained with that first solder refining slag. Because the first solder refining slag is enriched in tin
BE2018 / 5875 and / or lead facilitates downstream recovery of the solder metals (i.e. tin and / or lead) from this first solder refining slag.
Applicants have also found that the formation of the first diluted copper metal composition according to the present invention offers the additional advantage that more tin and / or lead can be introduced with the raw materials. This considerably broadens the acceptability criteria for any raw materials that may additionally be added to step b), ie in addition to the black copper, but also in the steps downstream thereof, such as in steps h), j) and d), and in step c ), which is introduced later in this document. Moreover, this also considerably eases the acceptability criteria for the black copper itself. This feature thus considerably broadens the acceptability criteria for the raw materials used in the production of the black copper, usually obtained as the main product from a smelting furnace step. As a result, the smelting furnace step may accept many more low-quality raw materials that are more widely available at more economically attractive conditions.
The applicants have further established that the formation of the first diluted copper metal composition according to the present invention entails the additional advantage that in step d) a better separation can be obtained between the copper and the nickel intended to be incorporated into the first diluted copper metal composition. and the tin and lead intended to enter the first solder refining slag.
In the process according to US 3,682,623, the 3% by weight of Cu in the 29.5 tonnes of slag of Table XIV represents 885 kg of Cu, or 1.46% by weight of all copper introduced upstream into the process starting from the first black copper refining step (Table VI), which comes to a total of 60.7 tonnes of copper. In the slag of Table XIV, 19.2% of all nickel introduced upstream into the process is recovered. Applicants have found that the present invention has the advantage that more of the copper and / or nickel can be derived to product streams in which these metals are more desirable.
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The amounts of copper and / or nickel that end up in the crude solder as impurities represent, together with the iron present, a burden on the refining process of crude solder, in particular when this is done using silicon metal as set out in the patent. DE 102012005401 A1, and are therefore undesirable. Applicants have found that downstream of step d) a raw solder metal can be produced which contains considerably less than the 18.11% by weight of copper, nickel and iron combined in US 3,682,623.
The applicants have further established that the first diluted copper metal phase of the present invention, which can be recovered from the re-treatment of copper refiner slag, may contain much less non-valuable metals. In US 3,682,623, the black copper for recycling (Table XIV) contains only 97.52% by weight of the total of Cu, Sn, Pb and Ni, leaving 2.48% by weight as a balance. This difference with US 3,682,623 brings the advantage that the first diluted copper metal phase according to the present invention is much easier to process further, especially for the recovery of the valuable metals contained in the stream.
The applicants have further established that the first diluted copper metal phase of the present invention recovered from step d) may also contain relatively large amounts of tin and / or lead. This entails the advantage that the corresponding slag phase obtained from step d), ie the first solder refining slag which, with sufficient time and mixing, must be in equilibrium with the first diluted copper metal phase, is also richer in tin and / or lead. As a result, more tin and / or lead becomes available for recovery downstream through the further processing of the first solder refining slag for the recovery therefrom of the solder metals, i.e. the tin and / or the lead. The overall result is that more crude solder can be produced in proportion to the amount of copper produced by the method of the present invention. This positive effect entails the associated additional benefit that a considerably higher amount
BE2018 / 5875 high purity tin product can be produced in proportion to the copper production rate of the process of the present invention. Because the co-production of tin generates an additional income on top of the income from copper production, this advantage can mean a significant economic added value for the person carrying out the process.
The applicants have further established that the more significant presence of tin and / or lead in the first diluted copper metal phase that is recovered from step d) makes it technically easier, and also more economically interesting, to recover the tin and / or lead from this stream by processing this stream separately, instead of simply recycling this stream as such to the first copper refining step b), as is done in US 3,682,623. Applicants have determined that the first diluted copper metal phase or composition of the present invention, and which can be obtained from step d) of the method of the present invention, is now extremely suitable for further separation in a stream with a higher concentration to tin and / or lead on the one hand and a stream with a higher concentration of copper and / or nickel on the other. The formation of another stream with a higher concentration of tin and / or lead entails the possibility of generating a tin by-product with an even greater purity in relation to copper production, which adds to the advantages set out above on that subject. Even if, following that additional separation, at least a portion of the stream with a higher concentration of copper and / or nickel would be recycled to the first copper refining step b), similar to what happened in US 3,682,623, there would be less tin and / or lead are present in that recycling stream in proportion to the copper content, and therefore more furnace volume becomes available for processing additional fresh feeds in the steps through which this recycling stream would pass.
The applicants have furthermore found that the removal of significant amounts of tin and / or lead together with the first diluted copper metal phase in step d) entails the advantage that less volume of first solder refining slag must be processed in the
BE2018 / 5875 downstream processing step, such that - for a given available oven volume - more space becomes available for introducing extra fresh feed into this downstream processing step.
Applicants have also found that the process of the present invention is extremely effective for producing a slag phase, ie the first solder refining slag, which is particularly suitable for producing a derived raw solder current that can serve as an intermediate for the recovery of tin / or high purity lead products. Applicants have found that this effectiveness is due in part to obtaining, in step d), the first diluted copper metal composition, but also to the sequence of oxidation and reduction steps as prescribed in the method of the present invention.
The applicants have furthermore established that the method according to the present invention is also extremely energy-efficient. In step d), the copper refining slag added in step i) introduces oxygen, and acts as an oxidizing agent for impurities in the first liquid bath. The copper oxides in the copper refining slag smoothly reduce to elemental copper, releasing the oxygen and making oxygen available to convert those metals that have a higher affinity for oxygen than copper from their elemental metal form to oxides under the conditions of the process . The elemental copper formed in step d) thereby passes to the metal phase and leaves step d) as part of the first diluted copper metal composition. The metals that are converted to their oxides in step d) will pass to the slag phase and are recovered in the first solder refining slag. Applicants have found that in step d) a substantial amount of Sn and / or Pb can be transferred from the metal phase present as part of the furnace charge to the first solder refining slag formed at the end of step d). Applicants have also found that these chemical conversions in step d), from copper oxides to elemental copper and from tin, lead or other metals to their oxides, can be accomplished with relatively little additional energy input, external
BE2018 / 5875 oxidizing agents and / or reducing agents, and therefore with a relatively limited consumption of energy or process chemicals.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a process flow diagram of a preferred embodiment of the method according to the present invention.
DETAILED DESCRIPTION
The present invention will be described below in specific embodiments and with possible reference to specific drawings; however, it is not limited to that, but is only determined by the conclusions. The described drawings are only schematic and are non-limiting. In the drawings, the size of some elements for illustrative purposes may be magnified and not drawn to scale. The dimensions and relative dimensions do not necessarily correspond to actual practical embodiments of the invention.
Furthermore, the terms first, second, third, and the like, in the description and claims, are used to distinguish between similar elements, and not necessarily to describe a sequential or chronological order. The terms are interchangeable under appropriate conditions, and the embodiments of the invention may function in sequences other than described or illustrated herein.
Furthermore, the terms upper, lower, top, bottom, and the like, in the description and the claims, are used for descriptive purposes, and not necessarily to describe relative positions. The terms thus used are interchangeable under appropriate circumstances, and the embodiments of the invention described herein may function in orientations other than described or illustrated herein.
The term "comprising", used in the claims, should not be interpreted as being limited to the means that
BE2018 / 5875 in its context. It does not exclude other elements or steps. The term is to be interpreted as the required presence of the stated properties, numbers, steps or components, but does not exclude the presence or addition of one or more other properties, numbers, steps or components, or groups thereof. The scope of the expression "an item comprising means A and B" should therefore not be limited to an object composed solely of components A and B. It means that for the subject matter of the present invention, A and B are the only relevant components. Accordingly, the terms "include" or "enclose" also include the more restrictive terms "consist essentially of" and "consist of". Therefore, when "include" or "contents" is replaced with "consist of," these terms represent the basis of preferred but narrowed embodiments, which are also provided as part of the contents of this document relating to the present invention.
Unless otherwise specified, all values specified in this document include the range up to and including the end points indicated, and the values of the components or components of the compositions are expressed in percent by weight, or percent by weight, of each ingredient in the composition.
In addition, each compound used in this document can be interchangeably discussed based on its chemical formula, chemical name, abbreviation, etc.
Within the context of the present invention, the term "at least in part" includes its end point "complete". With regard to the extent to which a particular oxidation or reduction step of the process is carried out, a typical preferred embodiment is a partial implementation. With regard to the addition or recycling of a process stream in a particular process step, a typical preferred embodiment is the operating point "fully" within the range covered by the term "at least partially".
In the context of the present invention, "smelter", "melting", "melting" or similar derivations of "melting out" means
BE2018 / 5875 is a method that involves much more than just changing the aggregation state of a substance from solid to liquid. In a pyrometallurgical smelter step, various chemical processes also occur that convert certain chemical compounds into other chemical compounds. Important of these conversions can be oxidations, whether or not accompanied by the formation of an oxide, or reductions, whereby the oxidation state of some atoms change.
In the context of the present invention, "scratch" or "scratch" means an often pasty substance that forms as a result of an operational step, and which separates from another liquid phase, usually under the influence of gravity, and usually comes to the surface. The scratch or scratches are therefore usually mechanically scraped or removed from the underlying liquid.
By "the solder", or also "the solder", is meant in the context of the present invention a metal composition that is rich in tin and / or lead, but which may also contain other metals. Solder typically has a relatively low melting temperature, which makes the composition suitable for being able to form a metal connection between two other metal parts, the so-called "soldering" after cooling to a relatively limited temperature.
In this document, unless otherwise stated, quantities of metals and oxides are expressed in accordance with current practice in pyrometallurgy. The presence of each metal is generally expressed as its total presence, regardless of whether the metal is present in its elemental form (oxidation state = 0) or in any chemically offered form, typically an oxidized form (oxidation state> 0) . For the metals that can be relatively easily reduced to their elemental form, and that can appear as molten metal in the pyrometallurgical process, it is quite common to express their presence in terms of their elemental metal form, even when the composition of a slag is indicated, while the majority of such metals may in fact be present in oxidized form. Therefore, in the composition of a snail in this
BE2018 / 5875 document the content of Fe, Zn, Pb, Cu, Sb, Bi as elemental metals. Less noble metals are more difficult to reduce under non-ferrous pyrometallurgy conditions and usually occur in oxidized form. These metals are usually expressed in terms of their most common oxide form. Therefore, in slag compositions, the Si, Ca, Al, Na content is generally expressed as SiO 2, CaO, Al 2 O 3, Na 2 O, respectively.
Unless otherwise specified or for aqueous compositions, the concentrations in this document are expressed in relation to the dry weight of the total composition, and therefore without any water or moisture present.
Applicants have found that the results of a chemical analysis of a metal phase are considerably more reliable than those of an analysis of a slag phase. In this document, when values are derived from a material balance over one or more process steps, applicants prefer to base such calculations, if possible, on as many metal phase analyzes as possible, and to minimize the use of slag analysis . For example, applicants prefer to calculate the recovery of tin and / or lead in the first copper refining slag from step b) on the basis of the amount of tin and / or lead in the combined feed to step b) that is no longer recovered in the first enriched copper metal phase from step b), rather than based on the concentration of tin and / or lead reported for the first copper refining slag.
The applicants have furthermore found that an analysis of a slag phase that is further processed can often be corrected by drawing up a mass balance over the downstream process step or steps, and by calculating, using the quantities of the products obtained from the downstream step in combination with the analysis of these products, at least one of which is preferably a liquid metal product, which yields much more reliable analytical results. Such
BE2018 / 5875 back calculation can be performed individually for several of the relevant specific metals, and can make it possible to make reliable material balances over most individual steps of the method according to the present invention. Such a recalculation can also be useful in determining the composition of a liquid metal stream where it can be particularly difficult to obtain a representative sample from it, for example a molten solder metal stream containing large amounts of lead together with tin.
Applicants prefer the use of X-ray fluorescence (X-ray fluorescence, XRF) for analyzing a metal phase in the context of the present invention. For this analysis, the applicants prefer to take a sample of the molten liquid metal, and the applicants preferably use a sampling device for immediate analysis in the copper refining of the Heraeus Electro Nite company, which rapidly produces a solid and cooled sample. provided for further processing. A surface of the cold sample then undergoes suitable surface treatment before the analysis is performed using an XRF probe. However, the XRF analysis technique does not provide an analysis of the oxygen content in the sample. Therefore, if necessary, to determine the complete composition of a metal phase including the oxygen content, the applicants prefer to measure the oxygen content of the metal in the molten liquid metal present in the furnace separately, preferably using a disposable electrochemical sensor for single-use batch processes in the copper refining offered by Heraeus Electro Nite. The analytical result of the analysis of the metal phase by XRF, as described above, can then be adjusted if desired for the oxygen content obtained from the individual oxygen analysis. The compositions mentioned in the Example of this document have not been adjusted to take into account their oxygen content.
The present invention deals primarily with the recovery of the intended metals copper, nickel, tin and / or lead
BE2018 / 5875 product streams that are suitable for extracting high-quality metal products from high purity. The process of the present invention comprises various process steps and these process steps can be categorized either as an oxidation step or as a reduction step. With this category, applicants want to indicate the chemical reactions to which these target metals can be subjected. Thus, a reduction step involves reducing at least one of these target metals from at least one of its corresponding oxides to its elemental metal form for the purpose of causing that metal in the furnace to pass from the slag phase to the metal phase. Such a reduction step is preferably stimulated by the addition of a reducing agent, as explained in various places in this document. The reduction steps are the process steps with reference numbers 400, 600, 700, 900, 1000 and 1100. In an oxidation step, the main objective is the conversion of at least one of the targeted metals to at least one of its corresponding oxides, with the aim of forming that metal in the furnace from the metal phase to the slag phase. The oxygen for that conversion can be supplied in the context of the present invention from various sources. The oxygen does not necessarily have to come from air or oxygen that can be blown into the liquid bath. The oxygen can also be supplied by introducing a slag phase obtained from another process step and in which the oxygen is bound in an oxide of at least one other metal. Thus, an oxidation step in the context of the present invention can optionally be performed without any injection of air or oxygen. The oxidation steps are therefore the process steps with reference numerals 100, 200, 300, 500, 800 and 1200.
Among the intended metals recovered by the present invention, Sn and Pb are considered "the solder metals". These metals differ from the other intended metals, copper and nickel, because mixtures containing large quantities of these metals usually have a much lower melting point than mixtures containing large quantities of copper and / or nickel. Of such
BE2018 / 5875 compositions were already used millennia ago to create a permanent bond between two pieces of metal, by first melting the solder, applying it, and allowing it to cure. The solder therefore had to have a lower melting temperature than the metal of the pieces that were connected to it. In the context of the present invention, a solder product or solder metal composition, two terms that are used interchangeably in this document, means metal compositions in which the combination of the solder metals, and thus the content of Pb plus Sn, represents most of the composition , ie at least 50% by weight and preferably at least 65% by weight. The solder product may further contain small amounts of the other target metals copper and / or nickel, and of non-target metals, such as Sb, As, Bi, Zn, Al and / or Fe, and / or elements such as Si. Because the method is aimed at the production of a crude solder product and a copper product, it is expected in the context of the present invention that the crude solder product or raw solder metal composition is obtained using the method in steps e) and / or n) also contains a measurable quantity of at least copper, albeit only as unavoidable impurity.
In one embodiment, the first diluted copper metal composition of the present invention comprises at least 58% by weight of copper, preferably at least 60% by weight, more preferably at least 62.5% by weight, preferably at least 65% by weight, more preferably at least 67.5% by weight, even more preferably at least 70% by weight, even more preferably at least 72.5% by weight, preferably at least 75% by weight, more preferably at least least 77.5% copper. Applicants have found that copper acts as a carrier and / or entrainer for tin and / or lead in the process steps prior to the production of the first diluted copper metal composition of the present invention. The presence of more copper in the first diluted copper metal composition of the present invention means that more copper is available in the upstream process steps, and that tin and / or lead can therefore be removed all the better from a stroke that
BE2018 / 5875 is in equilibrium with the metal phase containing the copper, which means in particular that more tin and / or lead can be withdrawn from the first spent slag of step c), a step introduced later in this document said spent slag being in equilibrium with the first lead-tin-based metal composition. This entails the advantage that more tin and / or lead can become part of the first raw solder metal product obtained from the method according to the present invention.
In one embodiment, the first diluted copper metal composition according to the present invention comprises at most 84% by weight of copper, preferably at most 83% by weight, more preferably at most 82% by weight, even more preferably at most 81% by weight, even more preferably at most 80% by weight, preferably at most 77.5% by weight, more preferably at most 75% by weight, even more preferably at most 72.5% by weight, preferably at most at most 70% by weight, more preferably at most 67.5% by weight of copper. Applicants have found that it is advantageous to limit the presence of copper in the first diluted copper metal composition according to the present invention to below the prescribed limits, since this also limits the presence of copper in the metal phases formed in the upstream process steps. Applicants have found that an excessive presence of copper in those metal phases leads to a higher presence of copper in the slag phases that are in equilibrium with these metal phases. Because the copper in those slag phases can mean a direct loss of valuable copper metal, and / or can indirectly form a burden for a downstream process, such an excessive presence of copper is preferably avoided.
The upper limit for copper in the first diluted copper metal composition according to the present invention is particularly relevant because it involves a limitation of the copper content of the first solder refining slag which is in equilibrium with it. This slag phase is then partially reduced, such that the majority of the tin and / or lead contained therein is reduced to the
BE2018 / 5875 corresponding elemental metals, but the copper is generally also reduced and the majority of the copper becomes part of the resulting first mixture of raw solder metal. This first mixture of raw solder metal should generally be subjected to further purification steps, such as a treatment with silicon metal as described in patent DE 102012005401 A1. Silicon metal is a fairly expensive process substance, and the treatment results in a silicon compound of the contaminating metal as a by-product to be reworked or disposed of. The copper entrained in this first raw solder metal thus leads to an increased consumption of silicon metal in such a purification step. Thus, it is advantageous to limit the copper in the slag phase that is in equilibrium with the first diluted copper metal composition of the present invention, a purpose to which very much is contributed by limiting the copper content in the first diluted copper metal composition of the present invention to below the indicated limits.
The upper limit for copper in the first diluted copper metal composition according to the present invention is also relevant because it leaves more room for processing more tin, a metal that is available to a limited extent and therefore can often achieve a higher economic upgrading than copper. Limiting the copper, and as a result thereof processing more tin, can thus provide considerable advantages for the person carrying out the process.
In one embodiment, the first diluted copper metal composition of the present invention comprises at least 7.5 weight percent tin, preferably at least 8.0 weight percent, more preferably at least 8.5 weight percent, even more preferably at least at least 9.0% by weight, even more preferably at least 9.5% by weight, preferably at least 10.0% by weight, more preferably at least 10.5% by weight, even more preferably at least at least 11.0% by weight, even more preferably at least
11.5% by weight, preferably at least 12.0% by weight, more preferably at least 12.5% by weight of tin. Applicants have found that when more tin is present in the first diluted copper metal composition according to
BE2018 / 5875, there is also more tin present in the first solder refining slag which is in equilibrium with the metal phase. Because tin will be recovered from the first solder refining slag, it is advantageous to provide more tin in the slag phase, and consequently also in the first diluted copper metal composition according to the present invention.
In one embodiment, the first diluted copper metal composition according to the present invention comprises at most 24% by weight of tin, preferably at most 23% by weight, more preferably at most 22% by weight, even more preferably at most 21% by weight, even more preferably at most 20% by weight, preferably at most
18.5% by weight, more preferably at most 17% by weight, even more preferably at most 15% by weight, even more preferably at most
12.5% by weight, preferably at most 10% by weight, more preferably at most 7.5% by weight of tin. Applicants have found that it is advantageous to limit the presence of tin in the first diluted copper metal composition according to the present invention to below the prescribed limits because it leaves room for the presence of copper and / or lead. The benefits of a copper content that is above certain limits are described elsewhere in this document. The presence of more lead brings with it other advantages that are described elsewhere in this same document.
In one embodiment, the first diluted copper metal composition of the present invention comprises at least 3.0% by weight of lead, preferably at least 4.0% by weight, more preferably at least 5.0% by weight, even more preferably at least at least 6.0% by weight, preferably at least 7.0% by weight, more preferably at least 8.0% by weight, even more preferably at least 9.0% by weight, preferably at least 10, 0% by weight, more preferably at least 11.0% by weight of lead. Applicants have found that more lead in the first diluted copper metal composition of the present invention brings the advantage that it improves the physical separation of the metal phase from the slag phase in the process step leading to the first diluted copper metal composition of the present invention. The applicants have also determined
BE2018 / 5875 that a higher lead content in the first diluted copper metal composition of the present invention due to equilibrium also results in more lead in the slag phase that is equilibrium therewith. It is from this slag phase that the first raw solder metal by-product will be generated. Thus, more lead in this slag phase results in a larger amount of lead that may end up in the first raw solder metal by-product of the process. More lead in this first raw solder metal by-product produces downstream positive effects for the process when the first raw solder metal by-product is subjected to refining steps, as required when the first raw solder metal by-product is the raw material for deriving high quality purity tin and / or lead products , for example, by vacuum distillation. Applicants have also found that a greater presence of lead can have positive effects for processing, such as smoother phase separations, in various steps that can be performed as part of the conversion of the first raw solder metal by-product to high-quality tin and / or lead products of higher purity.
In one embodiment, the first diluted copper metal composition of the present invention comprises at most 14% by weight of lead, preferably at most 13% by weight, more preferably at most 12% by weight, even more preferably at most 11% by weight, even more preferably at most 10.0% by weight, preferably at most 9.5% by weight, more preferably at most 9.0% by weight, even more preferably at most 8.5% by weight, even more preferably at most 8.0% by weight, preferably at most 7.5% by weight, more preferably at most 7.0% by weight of lead. Applicants have found that it is advantageous to limit the presence of lead in the first diluted copper metal composition according to the present invention to below the prescribed limits because it leaves room for the presence of copper and / or tin. The benefits of a copper content that is above certain limits are described elsewhere in this document. The
BE2018 / 5875 presence of more tin brings other benefits that are described elsewhere in this same document.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 0.60% by weight of iron, more preferably at most 0.50% by weight, even more preferably at most 0.40% by weight, with even more preferably at most 0.30% by weight, preferably at most 0.25% by weight, more preferably at most 0.20% by weight, even more preferably at most 0.10% by weight, with even more preferably at most 0.05% by weight of iron.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 3.0% by weight of zinc, preferably at most 2.5% by weight, more preferably at most 2.0% by weight, even more preferably at most 1.5% by weight, even more preferably at most 1.0% by weight, preferably at most 0.05% by weight of zinc.
In one embodiment, the diluted copper metal composition of the present invention comprises at most
1.5% by weight antimony, preferably at most 1.25% by weight, more preferably at most 1.00% by weight, even more preferably at most 0.75% by weight, even more preferably at least at most 0.50% by weight, preferably at most 0.30% by weight, more preferably at most 0.20% by weight of antimony.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 15% by weight of nickel, preferably at most 14.0% by weight, more preferably at most 13.0% by weight, even more preferably at most 12, 0% by weight, even more preferably at most 11.0% by weight, preferably at most 10.0% by weight, more preferably at most 9.0% by weight, even more preferably at most 8, 0% by weight, even more preferably at most 7.0% by weight of nickel.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 0.30% by weight of silver, preferably at most 0.27% by weight, more preferably
BE2018 / 5875 at most 0.25% by weight, even more preferably at most 0.20% by weight, even more preferably at most 0.15% by weight of silver.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 0.1 wt% of bismuth, preferably at most 0.10 wt%, more preferably at most 0.09 wt%, even more preferably at most 0.08% by weight, even more preferably at most 0.07% by weight, preferably at most 0.06% by weight, more preferably at most 0.05% by weight, even more preferably at most 0.04% by weight, even more preferably at most 0.03% by weight, preferably at most 0.02% by weight, more preferably at most 0.01% by weight, even more preferably at most 0.005% bismuth.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 0.15% by weight arsenic, preferably at most 0.10% by weight, more preferably at most 0.08% by weight, even more preferably at most 0.06% by weight, even more preferably at most 0.05% by weight of arsenic.
In one embodiment, the diluted copper metal composition of the present invention comprises at most 1.0% by weight of sulfur, preferably at most 1.00% by weight, more preferably at most 0.90% by weight, even more preferably at most 0.80% by weight, even more preferably at most 0.70% by weight, preferably at most 0.60% by weight, more preferably at most 0.50% by weight, even more preferably at most 0.40% by weight, even more preferably at most 0.30% by weight, preferably at most 0.25% by weight, more preferably at most 0.20% by weight, even more preferably at most 0.15% by weight, even more preferably at most 0.10% by weight, preferably at most 0.05% by weight of sulfur.
Applicants prefer that the concentrations of the metals iron, zinc, antimony, nickel, silver, bismuth and arsenic, and the element sulfur, in the diluted copper metal composition of the present invention, independently of each other and individually, correspond to the upper limits as indicated above. This brings it
BE2018 / 5875 has the advantage that the further processing of the diluted copper metal composition is facilitated and has fewer operational problems, fewer discharge problems, realizes better separations, and can be made simpler and therefore less complicated. A lower amount of sulfur can also lead to a lower vapor emission. The presence of less antimony and / or less arsenic can also lead to fewer safety risks, because in certain process steps these metals can create a risk for the formation of the highly toxic gasses stibine (SbH3) or arsine (AsH3). Iron can present an explosion hazard if a molten liquid containing FeO is quenched by direct contact with water.
In one embodiment, the diluted copper metal composition of the present invention comprises at least 4.0% by weight of nickel, more preferably at least 5.0% by weight, even more preferably at least 6.0% by weight, with even more preferably at least 7.0 wt%, preferably at least 8.0 wt%, more preferably at least 9.0 wt%, even more preferably at least 10.0 wt%, with even more preferably at least 11.0 wt% nickel. Applicants have found that the diluted copper metal composition of the present invention makes it possible to remove more nickel from the process by this route. This brings with it the advantages that (i) less nickel has to find its way through the other high-quality products, such as a high-purity copper that can be derived from the enriched copper metal phase obtained from step b) or h), or as a raw solder current derived from the first solder refining slag obtained from step d), and (ii) allowing more nickel to be admitted as part of the black copper provided in step a) without aggravating the problems that nickel entails when present in one of the high-quality products of the process: high-quality copper and raw solder. This advantage (ii) entails the additional advantage that the process steps used to provide the black copper as part of step a) can incorporate base materials that contain more nickel and that due to that higher nickel content more spacious
BE2018 / 5875 and / or at more attractive economic conditions.
In one embodiment of the method of the present invention, at least 38% by weight of the total amount of the tin and the lead processed through process steps b) and / or h) are recovered in the first copper refining slag and the second copper refining slag together, preferably at least 40% by weight, more preferably at least 45% by weight, even more preferably at least 50% by weight, preferably at least 60% by weight, more preferably at least 70% by weight, with even more preferably at least 80% by weight, even more preferably at least 85% by weight, preferably at least 90% by weight, more preferably at least 92% by weight, even more preferably at least 94% by weight. %, even more preferably at least 95% by weight of the total amount of the tin and the lead processed through process steps b) and / or h). Applicants have found that a high recovery of the tin and / or lead in the early slag of the copper refining step sequence is advantageous for obtaining a better separation between the copper on the one hand, and the solder metal tin and / or lead on the other hand.
In one embodiment of the method of the present invention, at least 8.5% by weight of the total amount of the tin and lead processed through process step b) is recovered in the first copper refining slag, preferably at least 10% by weight , more preferably at least 15% by weight, even more preferably at least 20% by weight, preferably at least 30% by weight, more preferably at least 40% by weight, even more preferably at least 45% by weight. %, even more preferably at least 50% by weight, preferably at least 55% by weight, more preferably at least 60% by weight, even more preferably at least 64% by weight, even more preferably at least at least 68% by weight of the total amount of the tin and lead processed through process step b). Applicants have found that the earlier in the sequence of the copper refining steps b), h) and j) more of the tin and / or lead is oxidized and transferred to the copper refining slag phase, the
BE2018 / 5875 more clearly the global separation between the copper on the one hand, and the solder metals tin and / or lead on the other hand can be accomplished.
In an embodiment of the method of the present invention, at least 41.0% by weight of the total amount of the tin processed through process steps b) and / or h) are recovered in the first copper refining slag and the second copper refining slag together, at preferably at least 45% by weight, more preferably at least 50% by weight, even more preferably at least 55% by weight, preferably at least 60% by weight, more preferably at least 65% by weight, with still more more preferably at least 70% by weight, preferably at least 75% by weight, more preferably at least 80% by weight, more preferably at least 85% by weight, preferably at least 90% by weight, more preferably at least 92% by weight of the total amount of the tin processed through process steps b) and / or h).
In an embodiment of the method of the present invention, at least 34.5% by weight of the total amount of the lead processed through process steps b) and / or h) is recovered in the first copper refining slag and the second copper refining slag together, at preferably at least 35% by weight, more preferably at least 40% by weight, even more preferably at least 45% by weight, preferably at least 50% by weight, more preferably at least 55% by weight, with still more more preferably at least 60% by weight, even more preferably at least 65% by weight, preferably at least 70% by weight, more preferably at least 75% by weight, even more preferably at least 80% by weight , preferably at least 85% by weight, more preferably at least 90% by weight, even more preferably at least 91% by weight of the total amount of the lead processed through process steps b) and / or h).
In one embodiment of the method according to the present invention, the recovery of tin in step b) as part of the first copper refining slag, relative to the total amount of tin present in step b), is at least 20%, preferably at least 30%, more preferably at least 40.00%, even more preferably at least 45%, even more preferably at least 50%, preferably at least 55%,
BE2018 / 5875, more preferably, at least 57%. No units need to be specified for the% recovery of a given element, because whether one looks at atoms or by weight, the% recovery remains the same.
In one embodiment of the method according to the present invention, the recovery of lead in step b) as part of the first copper refining slag, relative to the total amount of lead present in step b), is at least 20%, preferably at least 30.00%, more preferably at least 40%, even more preferably at least 45%, even more preferably at least 50%, preferably at least 55%, more preferably at least 60%.
The specified lower limit on the recovery of tin and / or lead in step b) as part of the first copper refining slag entails the advantage that already in the first oxidation step b) that is carried out on the black copper, a considerable amount of the present tin and / or lead is removed, along with significant amounts of other elements other than copper. This entails the advantage that fewer impurities are supplied to the steps performed downstream on the first enriched copper metal phase. This means that the downstream process steps on the first enriched copper metal phase must process a smaller number of impurities, and also face less volume intake by the first enriched copper metal phase. This generally means that more expensive furnace volume is released in the following process steps that are performed on the first enriched copper metal phase, which creates space for introducing additional material into these process steps, and thus creates the opportunity for increased production of final copper product within the same limitations concerning oven volume. The listed benefits are linked to the lower limit on the recovery of tin in step b), and also to the lower limit on the recovery of lead in step b), and to a combination of a lower limit on the recovery of tin with a lower limit on the recovery of lead in step b). The effects are cumulative with respect to the two metal tin and lead, and together they even produce an enhanced effect in proportion to the sum of the two individual effects.
BE2018 / 5875
Applicants have determined that the desired recoveries in step b) can be achieved by checking the presence of oxygen and / or oxygen donors in step a) within appropriate limits, if necessary combined with a controlled addition of scavengers for oxygen, and by addition of flux material.
In an embodiment of the present invention, the method further comprises the step of
c) partially reducing the first copper refining slag, forming a first lead-tin-based metal composition and a first spent slag, followed by separating the first spent slag from the first lead-tin-based metal composition, and adding the first lead-tin-based metal composition on the first liquid bath as the metal composition of step i) containing copper together with at least one soldering metal selected from tin and lead.
Applicants have found that the metal composition required in step i) can be easily provided as a derivative of the first copper refining slag obtained from step b), which is obtainable by subjecting the first copper refining slag from step b) to the partial reduction step c).
Applicants have determined that most of the copper supplied with the first copper refining slag will become part of the first lead-based metal composition forming in step c) in step c). The copper which ends up in the first lead-tin-based metal composition helps as a solvent for the tin and / or lead in process step c). The copper present in step c) thus helps to keep the tin and / or lead in the metal phase of step c), ie the first lead-tin-based metal composition, and reduces the amounts of tin and / or lead that may end up in the first spent snail from step c).
The applicants have further established that the inclusion of step c) in the method of the present invention entails several additional positive effects.
BE2018 / 5875
In step c), those metals in the furnace which have the lower affinity for oxygen under the conditions of the process can be selectively reduced to their respective metals. These reduced metals can then be separated as a liquid metal phase, leaving behind a liquid slag phase that has a lower concentration of those metals, but still contains metals and elements that have a higher affinity for oxygen. The purpose of this step is preferably to selectively recover most of the copper from the first copper refining slag as copper metal, together with as much of the tin and / or lead present as possible. The reduction in step c) is thus preferably carried out in such a way that the first spent slag comprises a total of at most 20% by weight of copper, tin and lead together. Preferably, the first spent slag comprises in total less than 20% by weight of copper, tin and lead together, more preferably much less. Strongly the amounts of copper, tin and / or lead in this slag are sufficiently low that they would no longer represent an economically significant value. Most preferably, the concentrations of copper, tin and / or lead are sufficiently low that the first spent slag would no longer cause environmental problems if it was disposed of as such, or would be acceptable to be disposed of after only limited further processing.
In the first spent slag of step c), most of the elements are preferably recovered which have a higher affinity for oxygen than tin and / or lead under the conditions of the process. This applies in particular to metals such as iron, aluminum, sodium, potassium, calcium and other alkali and alkaline earth metals, but also to other elements such as silicon or phosphorus.
Applicants have found that step c) preferably produces a first lead-tin-based metal composition that is highly suitable for further processing, in particular for producing a crude solder metal composition that may itself have commercial value and / or may be suitable for recovery of tin and / or lead products with a higher and commercially acceptable purity.
BE2018 / 5875
The applicants have surprisingly determined that it is possible to obtain a fairly clear separation in step c) between the valuable metals copper, nickel, tin and lead in the metal phase, and metals of lower value such as iron and aluminum, and other elements such as silicon in the snail phase. This allows a very high recovery of the valuable metals while producing a slag phase that exhibits a very low content of these metals, and can therefore be disposed of, either directly or with relatively limited further processing. Applicants believe that this clear separation is possible because the presence of copper in step c) as part of the combined furnace content is within a certain concentration window. On the one hand, the copper acts as an extraction agent for tin and lead from the slag phase. On the other hand, the presence of copper is sufficiently low for the loss of copper in the slag phase to remain very limited.
Another important advantage is that the process of the present invention comprising step c) has become much more tolerant to elements other than copper, most of which are elements that have a higher affinity for oxygen under the conditions of the process than copper, tin and lead, and therefore become part of the first spent snail. This considerably broadens the eligibility criteria for any raw materials that may additionally be added to step b), i.e. in addition to the black copper. Moreover, this also considerably eases the acceptability criteria for the black copper itself. This characteristic thus considerably broadens the acceptability criteria for the raw materials used in the production of the black copper, usually in a smelting furnace step. As a result, the smelting furnace step may accept many more low-quality raw materials that are more widely available at more economically attractive conditions.
Yet another advantage stems from the fact that in step b) the volume of slag is high in relation to the total furnace content. The removal of the slag from the furnace thus releases a substantial part of the volume of the furnace, such that in the further processing of the first enriched copper metal phase, which is usually carried out in the same
BE2018 / 5875 oven, extra space is created for the introduction of additional extra raw materials.
Applicants have found that this further processing of the first lead-tin-based metal composition from step c) can be performed much more efficiently and also much more efficiently thanks to the upstream removal from the process, as part of the first spent slag, of at least a substantial part of the metals and elements that have a high affinity for oxygen under the conditions of the process. Applicants have found that this feature of the process brings considerable benefits downstream of step b) in processing the first lead-tin-based metal composition.
A major advantage is that the volume of material to be processed downstream is considerably reduced by the removal in step c) of a considerable amount of material as the first spent slag, i.e. before the recovery of the soldering metals (Sn and Pb). In further downstream steps, this material would be dead weight, and would entail disadvantages rather than advantages. In the method of the present invention comprising step c), the further processing of the first lead-based metal composition can be performed much more efficiently in terms of volume, i.e. either smaller equipment can be used or the method of the present invention creates opportunities for processing additional streams for which the known methods would have no or less space. In addition, energy consumption can also be reduced in these downstream process steps, due to the smaller volume of hot material to be processed.
The applicants have furthermore surprisingly found that, by removing the first spent slag from the method of the present invention comprising step c), the separations in the pyrometallurgical process steps downstream, in particular for processing the first metal composition on a lead tin basis, also be greatly improved. Thanks to clearer divorces
BE2018 / 5875 between the respective metal phases and their corresponding slag phases, the downstream recovery of valuable metals can be carried out more efficiently and efficiently, ie with higher yields of high-quality product, lower rejection of valuable metals, and a lower required energy input, for example due to lower volumes to recycling flows.
An additional advantage of the method according to the present invention comprising step c) is that in the further processing of the first lead-tin-based metal composition, additional materials can be introduced thanks to the additional furnace space made available by removing the large volume of the first spent snail from the process. Such additional materials can for example be rich in tin and / or lead. Such additional materials may be, for example, process slags and / or scratches that are generated as by-products of downstream refining steps as part of the further purification of tin and / or lead streams into commercially valuable high-quality products.
Another important advantage of the method according to the present invention comprising step c) is that it allows a much larger amount of crude soldering co-product for the same amount of copper being processed. Applicants have found that the co-production of raw solder, relative to the amount of copper processed in the first copper refining step, can be increased by about 29% compared to the amounts obtained in the process described in U.S. Pat. No. 3,682,623 . The economic value of raw solder, in particular as a possible intermediate for the production of a high purity tin product, is considerable in relation to the value of the high-quality anode copper product that can be obtained from the black copper. The increase in the relative amount of crude soldering co-product in relation to the amount of copper that is processed in the first copper refining step, therefore, entails a considerable economic advantage for the person carrying out the process according to the present invention.
BE2018 / 5875
Applicants have also found that it is advantageous that step c) only takes up the first copper refining slag, and that the subsequent copper refining slags are better processed separately, and preferably each in a different way. Applicants have found that the first copper refining slag is the copper refining slag containing the largest total amount of elements other than copper, and in particular those elements which have a higher affinity for oxygen under copper conditions than copper, more particularly an affinity for oxygen which also higher than that of tin and lead. The applicants have therefore surprisingly determined that it is most effective to perform step c) on the first copper refining slag, i.e. before mixing in one of the other copper refining slags produced in process steps downstream of step b). Applicants have found that subsequent copper refining slags generally comprise higher concentrations of copper, and therefore applicants prefer to process these downstream copper refining slags differently than the first copper refining slag.
In an embodiment of the method of the present invention, the total feed to step c) comprises at least 29.0% by weight of copper, preferably at least 30.0% by weight, more preferably at least 31.0% by weight , even more preferably at least 32.0% by weight, even more preferably at least 33.0% by weight, preferably at least 34.0% by weight, more preferably at least 35.0% by weight even more preferably at least 36.0 wt%, preferably at least 37.0 wt%, more preferably at least 38.0 wt% copper.
In an embodiment of the method according to the present invention, the total feed to step c) comprises an amount of copper that is at least 1.5 times as high as the total amount of solder metals present, ie the sum of Sn plus Pb, preferably at least 1.6 times, more preferably at least 1.7 times, even more preferably at least 1.8 times, even more preferably at least 1.9 times, preferably at least 2.0 times, more preferably at least 2.1 times as high as the total amount of soldering metals present.
BE2018 / 5875
Applicants have found that the prescribed amount of copper entails the advantage that sufficient copper is present to act as a solvent for extracting solder metals from the slag phase to the first lead-tin-based metal composition, and therefore improves the recovery of valuable tin and / or lead from the slag in step c).
Applicants have found that the lower limit specified for the presence of copper, relative to the presence of the sum of Sn plus Pb present, in the total feed to step c) brings the advantage that a better extraction of Sn and P Pb is obtained from the slag phase, and that without adding significant amounts of copper in the slag phase. The applicants have found that the high presence of copper in the feed to step c) influences the balance for tin and lead between the slag and the metal phase at the end of step c), the transition of these solder metals from the slag phase to the metal phase is promoted. Applicants have found that this effect can be achieved without increasing the concentration of copper in the spent slag obtained from step c) to economically significant and possibly unacceptable levels. Applicants have found that the large amount of copper in the feed to step c) makes it possible to obtain a spent slag from step c) that contains only low concentrations of tin and / or lead, as well as copper. This entails the advantage that the spent slag from step c) requires less, or even no further processing, for its responsible disposal or for its use in a suitable downstream application.
Applicants have found that the high presence of copper relative to the amount of solder metals Pb plus Sn in the feed to step c), as indicated, entails the advantage of a higher recovery of the valuable metal tin, lead, and if also copper and possibly nickel, in product streams in which their presence is desired. This also lowers the
BE2018 / 5875 load that can be caused by the presence of these metals in product streams where they are less or not desired.
In an embodiment of the method of the present invention, the first lead-based metal composition comprises copper in the range of 40% to 90% by weight, preferably at least 50% by weight, more preferably at least 55% by weight. %, even more preferably at least 60% by weight, preferably at least 61% by weight, more preferably at least 62% by weight, even more preferably at least 63% by weight, preferably at least 64% by weight. %, more preferably at least 65% by weight, even more preferably at least 66% by weight. Applicants have found that the prescribed amount of copper entails the advantage that sufficient copper is present to act as a solvent for extracting solder metals from an overhead slag phase to the first lead-tin-based metal composition in the upstream process step, and therefore the recovery improves valuable tin and / or lead from this slag in the downstream step.
Applicants prefer that the first lead-tin-based metal composition is at most 85% by weight, preferably at most 80% by weight, more preferably at most 75% by weight, even more preferably at most 70% by weight. %, preferably at most 65% by weight of copper.
The applicants have found that the upper limit for copper in the first lead-tin-based metal composition is also relevant because it leaves more room for processing more tin and / or lead, of which tin in particular is a metal that is available to a limited extent and therefore often achieve a higher economic upgrade than the buyer. Thus, limiting the copper content and, as a result, processing more tin as part of the first lead-tin-based metal composition, and further downstream in steps d) and l), step 1 being introduced later in this document, can take considerable provide benefits to the process performer because it can allow higher production of raw solder as a downstream derivative of the process, and further downstream of
BE2018 / 5875 more high-quality products of tin of higher purity and / or of lead of higher purity.
In an embodiment of the method of the present invention, the first lead-based metal composition comprises tin and lead together in the range of 5.0% to 60%, preferably at least 10%, more preferably at least 15% by weight, even more preferably at least 17.5% by weight, preferably at least 18% by weight, more preferably at least 18.5% by weight, even more preferably at least 19% by weight. %, preferably at least 20% by weight, more preferably at least 22% by weight, even more preferably at least 24% by weight, preferably at least 26% by weight of tin and lead together, and optionally at most 50 % by weight, preferably at most 40% by weight, more preferably at most 30% by weight of tin and lead together. Satisfying the lower limit for tin and lead together entails the advantage that the overall process comprising the method of the present invention is capable of producing more raw solder for the same amount of copper product. The crude solder can then be used to derive high-purity high-purity tin and / or lead products that represent a major economic upgrading when derived from mixed metal base materials that also contain copper. More tin and / or lead in the first lead-tin-based metal composition therefore represents a significant economic advantage for the operator.
Complying with the upper limit for tin and lead together entails the advantage that more copper can be admitted into the first lead-tin-based metal composition. Under the conditions of the process, the presence of copper entails, within certain limits, the advantage that it acts as an extraction agent for tin and / or lead and therefore in step d) improves the separation between copper and nickel in the first diluted copper metal composition and, on the other hand, tin and lead in the first solder refining slag, but also in the downstream step where the first lead-tin-based metal composition is formed and is in equilibrium with a supernatant slag phase.
BE2018 / 5875
In an embodiment of the process of the present invention, the first lead-based metal composition comprises tin in the range of 2.0 wt% to 30 wt%, preferably at least 4.0 wt%, more preferably at least at least 6.0 wt%, even more preferably at least 8.0 wt%, preferably at least 9.0 wt%, more preferably at least 9.50 wt%, even more preferably at least 10.0% by weight, preferably at least 11.0% by weight of tin. More tin in the first lead-tin-based metal composition entails the advantage that more tin can end up in the first solder refining slag and / or in the third solder refining slag, and further downstream in any crude solder product that can be obtained as a derivative of the process according to the present invention. Tin is a metal that is available to a limited extent and therefore can often achieve a higher economic upgrade than copper and / or lead. Thus, processing more tin as part of the first lead-tin-based metal composition, and further downstream in steps d) and 1), where step 1 is introduced later in this document, can provide significant benefits to the person performing the process.
The presence of more tin in the first lead-tin-based metal composition also has the advantage that the upstream process steps from which the first lead-tin-based metal composition is obtained can incorporate base materials containing more tin, together with other elements or metals such as copper and / or lead. This broadens the acceptability criteria of base materials for those upstream process steps, which may therefore include base materials containing significant amounts of tin together with another specifically intended metal. Such more complex base materials sometimes find it difficult to find more valuable applications, and may therefore be available in relatively large volumes and at more economically attractive conditions. A wider acceptance of basic materials that contain more tin can therefore be an advantage for the operator.
In an embodiment of the method of the present invention, the first lead-based metal composition comprises lead in the range of 3.0 wt% to 40 wt%, preferably
BE2018 / 5875 at least 5.0% by weight, more preferably at least 6.0% by weight, even more preferably at least 8.0% by weight, preferably at least 9.0% by weight, more preferably at least 9.50% by weight, even more preferably at least 10.0% by weight, preferably at least 11.0% by weight, more preferably at least 12.0% by weight, even more preferably at least 13.0% by weight of lead. More lead in the first lead-tin-based metal composition entails the advantage that more lead can find its way into the first solder refining slag and / or into the third solder refining slag, and further downstream into any crude solder product that can be obtained as a derivative of the method of the present invention. Lead is a metal with a high density, much higher than other metals, and lead transfers this property to mixtures of which it forms part. In every step where a heavier liquid metal phase is to be separated from a lighter slag phase with which it has become equilibrated after chemical reactions have taken place, the presence of lead in the metal phase increases the density of the metal phase and consequently the difference in density between the slag phase and the metal phase. The presence of lead therefore promotes rapid and clear separation between the two liquid phases. The same effects of faster and clearer separations can be obtained by the presence of lead in downstream processes, for example process steps in which a crude solder current is refined by forming a scratch with lighter density, possibly as a result of chemical reactions. Thus, processing more lead as part of the first lead-based metal composition, and further downstream in steps d) and l), step 1 being introduced later in this document, can provide significant benefits to the person performing the process.
The presence of more lead in the first lead-tin-based metal composition also has the advantage that the upstream process steps from which the first lead-tin-based metal composition is obtained can incorporate base materials containing more lead, together with other elements or metals such as copper and / or tin. This broadens the acceptability criteria of
BE2018 / 5875 base materials for those upstream process steps, which may therefore include base materials containing significant amounts of lead together with another specifically intended metal. Such more complex base materials sometimes find it difficult to find more valuable applications, and may therefore be available in relatively large volumes and at more economically attractive conditions. A wider acceptance of basic materials that contain more lead can therefore be an advantage for the operator.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at most 10.0% by weight of copper, preferably at most 9.0% by weight, more preferably at most 8.0% by weight, with even more preferably at most 7.0% by weight, even more preferably at most 6.0% by weight of copper, preferably at most 5.5% by weight, more preferably at most 5.0% by weight, even more more preferably at most 4.5% by weight, preferably at most 4.0% by weight, more preferably at most 3.5% by weight, even more preferably at most 3.0% by weight, preferably at most at most 2.5% by weight, more preferably at most 2.0% by weight, even more preferably at most 1.5% by weight of copper, and optionally at least 0.1% by weight, preferably at least 0 5%, more preferably at least 1.0% by weight of copper. Applicants have found that compliance with the upper limit entails the advantage of a more economical and possibly even simpler further refining of the raw solder current that can be recovered downstream from the first solder refining slag.
Applicants have found that the presence of less copper in the first solder refiner slag also lowers the copper content of the first raw solder metal composition obtained in step e), a step introduced later in this document, since the copper is generally also reduced in step e) and the majority of the copper becomes part of the resulting first raw solder metal composition. The first raw solder metal composition should generally be subjected to further purification steps to lower the presence of others
BE2018 / 5875 metals than tin, lead and antimony in the raw solder metal composition, for example before this raw solder metal composition becomes suitable for the recovery of high purity tin and / or lead products. This includes the removal of copper. Such a treatment can be, for example, silicon metal, as described in the patent DE 102012005401 A1. Silicon metal is a fairly expensive process substance, and the treatment results in a silicon compound of the contaminating metal as a by-product to be reworked or disposed of. The copper entrained in the first raw solder metal thus leads to an increased consumption of silicon metal in such a purification step. It is therefore advantageous to limit the copper in the first solder refining slag.
The raw solder metal composition obtained from the method of the present invention, ie the first raw solder metal composition as obtained from step e) and / or the second raw solder metal composition obtained from step n) as described below, can be further treated to provide more of the remove contaminants in it, in particular copper. This can be accomplished by contacting the raw solder metal composition, as a molten liquid, with elemental silicon and / or aluminum, elements that bind to Cu, Ni and / or Fe under operating conditions and a separate silicide and / or aluminide alloy phase to shape. Applicants preferably use scrap containing silicon and / or aluminum. Preferably, the added material further comprises Sn and / or Pb, because these metals are easily upgraded to the respective high-quality products when introduced at this stage of the process. Because of the typical presence of Sb and As in the raw solder metal composition, the applicants prefer to use silicon and preferably avoid aluminum, although the latter is generally more readily available and more reactive. This avoids the formation of H 2 S, a toxic gas, and more exothermic reactions in the treatment vessel, and also avoids that the resulting alloy phase by-product, in contact with water, stibine and / or arsine, might
BE2018 / 5875, which are extremely toxic gases. The applicants have determined that the silicon feed for this treatment step may contain a limited amount of iron (Fe), without problems more than 1% by weight and without problems up to 5% by weight or even up to 10% by weight of Fe. The process can therefore be carried out using Si products that are unacceptable to other silicon consumers, such as rejected material from the production line, and which may therefore be more readily available. Applicants have found that the burden of processing this additional Fe, which also binds with Si, is usually smoothly compensated for by the advantageous conditions for providing the silicon source.
Applicants prefer to provide the silicon-containing feed in the form of granules, for example with a grain size of 2-35 mm, on the one hand to avoid losses due to dust and oxidation on the surface, and on the other to provide sufficient surface for the intended avoid chemical reactions and clogging of the strainer in the feed hopper. A powdered form of the silicon-containing feed for this refining step is preferably injected into the treatment step.
Applicants preferably bring the crude solder metal composition to a temperature of at least 800 ° C before the addition of the silicon and / or aluminum is started. In this further silicon treatment step, several of the chemical reactions are exothermic, and the reactions with nickel and with iron are more exothermic than the reaction with copper. Applicants therefore prefer to propel the reaction by adding more silicon-containing feed, at least until the temperature in the reaction vessel begins to fall again, a point indicating that Fe and / or Ni are about exhausted and Cu begins to respond. The additional amount of Si to be added can easily be determined based on the Cu content of the raw solder metal composition, and can therefore be predicted easily and fairly precisely.
BE2018 / 5875
Applicants prefer to carry out this silicon treatment in a so-called "shaking crucible", ie an oven moving horizontally along an elliptical path, because it combines a fairly intense mixing action with limited exposure to oxygen in the atmosphere, and a limited investment cost. If the supply to this treatment is on the cold side for a shaking crucible, the treatment step is preferably carried out in a top blown rotary converter or "top blown rotary converter" (TBRC) because of the better heating capacity.
Applicants prefer to monitor the addition of silicon by analyzing samples of the supernatant phase for Ni and Si, and add sufficient Si to avoid the formation of a 3rd Cu and Sn containing phase after cooling wherein this additional phase Sn would retain that more preferably should end up in the treated raw solder product of the treatment step.
Applicants prefer to perform this treatment step in batches. After the completion of the reaction, applicants prefer to pour the entire contents of the reactor into separator / drain crucibles for cooling, thereby first solidifying the supernatant alloying phase containing the impurities. The molten crude solder metal composition underneath can then be drained or drained, and the solid crust remaining in the crucible can be recovered as a product that can be called the "cuprofase", preferably for recovering the metals of interest therein, e.g. preferably by recycling this cuprofase to a suitable upstream pyrometallurgical process step. Applicants prefer to pour the contents of the reactor into the separating / draining crucibles for cooling at a temperature of at most 950 ° C, since this is the useful life of the crucibles, which are preferably made of cast steel, extends. Applicants have found that the crust can be easily removed from the separating / draining crucible, preferably by simply holding the crucible upside down while still warm, which has the advantage of
BE2018 / 5875 means that the crucible is quickly available for the next campaign, avoiding loss of time and loss of heat between two consecutive applications. An empty crucible is preferably kept warm until its next use to further extend its useful life. During this heating, the empty crucible is preferably placed on its side in a pre-heating position, a position that allows easy processing for the overhead crane.
The recovered cuprofase is then preferably re-melted, optionally with the addition of additional Pb, such as Pb scrap material, and preferably in a TBRC-type oven such that any solder trapped in the crust is incorporated in a Pb -rich metal phase that can be poured (and cured) for further processing. This "rinsing" of the cuprofase with Pb can be repeated, in view of the additional recovery of Sn that can be obtained, provided that sufficient elemental Si is still present. Applicants believe that Sn is also present in the cuprofase as part of an intermetal compound formed with Cu. The added Pb is presumably able to break this intermetal connection. The Cu can then react with Si still available to form its silicide, and the released Sn can dissolve in the Pb-containing liquid phase.
Rinsing the cuprofase with Pb entails the advantage that more Sn is recovered and that this extra Sn ends up in a stream that is already on its way to recovering a high purity tin product. Pb is particularly suitable as a rinsing material because, due to its high density, it is able to bring about a relatively fast and clear separation between the metal phase and the rinsed solid cup phase.
The rinsing liquid, ie molten Pb, which further contains the rinsed Sn, can be added without problem in the raw solder prepared for vacuum distillation as described in WO 2018/060202 A1, where it can be useful to control the Pb / Sn ratio of that bring electricity closer to its target value for optimum further processing.
BE2018 / 5875
The flushed cuprofase can then be recycled in various upstream process steps, for the purpose of recovering the Cu and / or Ni contained therein and / or to provide energy through the strong exothermic reaction when residual elemental silicon oxidizes to at least one of its oxides . Suitable steps to which the flushed cuprofase can be recycled are the copper refining steps b), h) and j), the slag processing step c), and the upstream smelting furnace step, as defined elsewhere in this document. Applicants have found that the flushed cuprofase can become sufficiently poor in Sn and / or Pb for it to be added in the oven where the first copper metal composition with high copper metal content, which is removed from the process after step 1), is prepared to be are cast into copper anodes containing impurities such as nickel.
Preferably, the first solder refining slag comprises at least 1.0% by weight of copper, more preferably at least 1.5% by weight, even more preferably at least 2.0% by weight, preferably at least 2.5% by weight. %, more preferably at least 3.0 wt%, even more preferably at least 3.5 wt% copper.
Applicants have also found that it is advantageous to tolerate an amount of copper in the first solder refining slag and to stay above the specified lower limit. Applicants have found that this has a positive effect on the upstream process steps, also with regard to the base materials that can incorporate these upstream process steps. At these levels, a higher presence of copper generally also means a higher presence of tin and / or lead, which can be very beneficial. Both of these positive technical effects are advantages that compensate for the load resulting from the presence of copper in the first solder refining slag, and as a result, the presence of copper in the first raw solder metal composition.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at least
BE2018 / 5875
2.0% by weight of tin and optionally at most 20% by weight of tin. Preferably, the first solder refining slag comprises at least 3.0% by weight of tin, more preferably at least 3.5% by weight, even more preferably at least 4.0% by weight, preferably at least 4.5% by weight. %, more preferably at least 5.0% by weight, even more preferably at least 5.5% by weight, preferably at least 6.0% by weight, more preferably at least 6.5% by weight, even more preferably at least 7.0% by weight, preferably at least 7.5% by weight, more preferably at least 8.0% by weight, even more preferably at least 8.5% by weight, preferably at least 9.0% by weight, more preferably at least 9.5% by weight, even more preferably at least 10.0% by weight, preferably at least 10.5% by weight, more preferably at least least 11.0% by weight of tin. Applicants have found that the more tin is present in the first solder refining slag, the more tin can end up in the first raw solder metal composition obtained downstream. Since high-purity tin is a commercial product with considerable economic added value, a larger amount of tin in the first raw solder metal composition makes it possible to recover a larger volume of high-purity tin from it.
Preferably, the first solder refining slag in the process of the present invention comprises at most 19% by weight of tin, more preferably at most 18% by weight, even more preferably at most 17% by weight, preferably at most 16% by weight , more preferably at most 15% by weight, even more preferably at most 14% by weight, preferably at most 13% by weight, more preferably at most 12% by weight, even more preferably at most 11% by weight. % tin. Applicants have found that satisfying the tin content at the specified upper limit entails the advantage of leaving room for other metals that may have benefits. In particular, the presence of significant amounts of lead in the first solder refining slag, a large portion of which ends up in the first raw solder metal composition, entails the advantage that the raw solder metal composition has a higher density, which is extremely useful in separating the solder from other phases such as
BE2018 / 5875 a slag phase or a scratch, for example during further downstream refining of the raw solder metal composition.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at least 9% by weight of lead and optionally at most 30% by weight of lead. Preferably, the first solder refining slag comprises at least 10% by weight of lead, more preferably at least 11% by weight, even more preferably at least 12% by weight, preferably at least 13% by weight, more preferably at least 14 % by weight, even more preferably at least 15% by weight, preferably at least 16% by weight, more preferably at least 17% by weight, even more preferably at least 18% by weight of lead. Applicants have found that more lead in the first solder refining slag leads to more lead in the first raw solder metal composition. More lead in this first raw solder metal product produces downstream positive effects for the process when the first raw solder metal product is subjected to refining steps, as required when the first raw solder metal product is the raw material for the derivation of high quality tin / or lead products of higher purity, for example by vacuum distillation. Applicants have also found that a greater presence of lead can have positive effects for processing, such as smoother phase separations, in various steps that can be performed as part of the conversion of the first raw solder metal product to high-quality tin and / or lead products of higher purity.
Preferably, the first solder refining slag in the process of the present invention comprises at most 28% by weight of lead, more preferably at most 26% by weight, even more preferably at most 24% by weight, preferably at most 23% by weight , more preferably at most 22% by weight, even more preferably at most 21% by weight, preferably at most 20% by weight, more preferably at most 19% by weight, even more preferably at most 18% by weight. %, preferably at most 17% by weight, more preferably at most 16% by weight and even more preferably at most 15% by weight of lead. Applicants have
BE2018 / 5875 has determined that it is advantageous to limit the presence of lead in the first solder refining slag in the method according to the present invention to below the prescribed limits, because this leaves room for the presence of tin. The presence of more tin entails the advantage that more tin can end up in the first raw solder metal composition and consequently more tin of high purity can be obtained as end product. Due to the high commercial value of tin of high purity, this technical advantage also means a great economic advantage.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at least 12% by weight of tin and lead together and optionally at most 50% by weight of tin and lead together. Preferably, the first solder refining slag comprises at least 13% by weight of tin and lead together, more preferably at least 14% by weight, even more preferably at least 15% by weight, preferably at least 16% by weight, more preferably at least 17% by weight, even more preferably at least 18% by weight, preferably at least 19% by weight, more preferably at least 20% by weight, even more preferably at least 21% by weight, preferably at least 22% by weight, more preferably at least 23% by weight, even more preferably at least 24% by weight, preferably at least 25% by weight, more preferably at least 26% by weight, with even more preferably at least 27% by weight, preferably at least 28% by weight, more preferably at least 29% by weight, even more preferably at least 30% by weight of tin and lead together. Applicants have found that the more tin and lead are present in the first solder refining slag, the more tin and lead can end up in the first raw solder metal composition. Because high-purity tin and lead are commercial products with significant economic added value, a larger amount of tin and lead together in the first raw solder metal composition makes it possible to recover a larger volume of high-purity tin and high-purity lead from it. This also entails the advantage that the process of the present invention can produce more crude solder for the same amount of copper production. The raw solder product can lead to the
BE2018 / 5875 production of higher purity tin products and / or higher purity lead products, ie products that can undergo significant economic upgrading, especially if the tin and / or lead is derived from mixed metal base materials, which often have a relatively lower economic value .
Preferably, the first solder refining slag in the process according to the present invention comprises at most 45% by weight of tin and lead together, more preferably at most 40% by weight, even more preferably at most 39% by weight, preferably at most 38 % by weight, more preferably at most 36% by weight, even more preferably at most 34% by weight, preferably at most 33% by weight, more preferably at most 32% by weight, even more preferably at most 31% by weight, preferably at most 30% by weight, more preferably at most 29% by weight, even more preferably at most 28% by weight, preferably at most 27% by weight, more preferably at most 26 % by weight, even more preferably at most 24% by weight of tin and lead together. Applicants have found that it is advantageous to limit the presence of tin and lead together in the first solder refining slag in the process according to the present invention to below the prescribed limits, since this leaves room for the presence of oxygen and of other metals the process conditions have a higher affinity for oxygen than copper, nickel, tin and lead. This applies in particular to metals such as iron, aluminum, sodium, potassium, calcium and other alkali and alkaline earth metals, but also to other elements such as silicon or phosphorus. These elements with a higher affinity for oxygen usually become part of the second spent slag obtained from step f), a step introduced later in this document, that is, they are removed from the process with a discharge stream. As a result, these elements do not end up as impurities in one of the high-quality metal products of the process, that is to say that these streams have a greater purity with regard to the desired metals. The higher tolerance for these elements with a higher affinity for oxygen than copper, nickel, tin and lead also broadens the acceptability criteria for the
BE2018 / 5875 basic materials for the method according to the present invention. These upstream steps may therefore absorb many more low-quality raw materials that are more widely available at more economically attractive conditions.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at most 4.0% by weight and optionally at least 0.2% by weight of nickel, preferably at most
3.5% by weight, more preferably at most 3.0% by weight, even more preferably at most 2.5% by weight, preferably at most 2.0% by weight, more preferably at most 1, 5% by weight, even more preferably at most 1.0% by weight of nickel. Applicants have found that the behavior of nickel is very similar to that of copper in step e), which is described in more detail below. The advantages of keeping the nickel content of the first solder refining slag within the prescribed limits therefore correspond to the advantages described elsewhere in this document for copper, or for copper and nickel together. Preferably, the first solder refining slag comprises at least 0.20 wt% nickel, more preferably at least 0.25 wt%, even more preferably at least 0.30 wt%, preferably at least 0.35 wt. %, more preferably at least 0.40% by weight, even more preferably at least 0.45% by weight of nickel. This entails the advantage that the upstream process steps from which the first solder refining slag is obtained are capable of incorporating base materials containing nickel. These base materials are less acceptable in other processes because of the nickel present therein, and can therefore be available more widely and at more economically attractive conditions.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at most 10.0% by weight of copper and nickel together, preferably at most 9.0% by weight, more preferably at most 8.0% by weight, even more preferably at most 7.0% by weight, even more preferably at most 6.0% by weight, preferably at most 5.5% by weight, more preferably at most 5.0% by weight, even more preferably at most 4.5% by weight, preferably at most 4.0% by weight,
BE2018 / 5875, more preferably at most 3.5% by weight, even more preferably at most 3.0% by weight of copper and nickel together. Applicants have found that smaller amounts of copper and / or nickel in the first solder refining slag leave more room for more easily oxidizing metals, such as iron, which tend to lower the viscosity of the slag phase, which is advantageous for good quality and rapid separation of the metal phase and the slag phase in the furnace, in particular as part of step e), which is described in more detail below.
In an embodiment of the method according to the present invention, the first solder refining slag comprises at least 10% by weight and optionally at most 30% by weight of iron. Preferably, the first solder refining slag comprises at least 11% by weight of iron, more preferably at least 12% by weight, even more preferably at least 13% by weight, preferably at least 14% by weight, more preferably at least 15 % by weight, even more preferably at least 16% by weight, preferably at least 17% by weight, more preferably at least 18% by weight, even more preferably at least 19% by weight, preferably at least 20% by weight % by weight, more preferably at least 21% by weight, even more preferably at least 22% by weight of iron. Preferably, the first solder refining slag comprises at most 29% by weight of iron, more preferably at most 28% by weight, even more preferably at most 27% by weight, preferably at most 26% by weight, more preferably at most 25 % by weight, even more preferably at most 24% by weight, preferably at most 23% by weight, more preferably at most 22% by weight, even more preferably at most 21% by weight, preferably at most 20% wt% iron. Applicants have found that iron is an advantageous reducing agent for metals that have a lower affinity for oxygen under the process conditions than iron, such as copper, nickel, tin and lead. Applicants therefore prefer to have a presence of iron in the first solder refining slag which meets the indicated limits because this allows an upstream process step to use significant amounts of iron as a reducing agent, which entails, for example, the advantage that it makes many of the upstream process steps more energy efficient. Another
BE2018 / 5875 has the advantage that the acceptability criteria for basic materials of these upstream process steps are also relaxed, which makes it possible to accept basic materials that may be more widely available and at more economically attractive conditions.
In an embodiment of the method of the present invention, the first solder refining slag comprises at least 0.003 wt.% Of antimony, preferably at least 0.004 wt.%, More preferably at least 0.005 wt.%, Even more preferably at least 0.010 wt. %, preferably at least 0.015% by weight, more preferably at least 0.020% by weight, even more preferably at least 0.025% by weight, preferably at least 0.030% by weight, and optionally at most 0.200% by weight, preferably at most 0.180% by weight, more preferably at most 0.150% by weight, even more preferably at most 0.100% by weight of antimony, preferably at most 0.090% by weight, more preferably at most 0.080% by weight, even more preferably at most 0.070% by weight, preferably at most 0.060% by weight, more preferably at most 0.050% by weight, even more preferably at most 0.040% by weight, even more preferably at most 0.030% by weight % antimony. Applicants have also found that most of the antimony as part of the first solder refining slag is usually reduced as part of step e), which is introduced later in this document, and most of it becomes part of the first raw solder metal composition. Applicants have further determined that an amount of antimony may be acceptable in the process steps carried out on the first raw solder metal composition, even when they aim at the recovery of high quality high purity tin and / or lead products. Applicants have found that an amount of antimony may be acceptable, and even desirable, in some of these high quality purity metal products. However, applicants have found that the ability to incorporate antimony in these downstream processes is limited with respect to the amount of lead present. Therefore, applicants also prefer the
BE2018 / 5875 specified upper limits for antimony as part of the first solder refining slag.
In an embodiment of the method according to the present invention, step c) comprises adding a first reducing agent to step c), preferably by adding the first reducing agent to the first copper refining slag prior to reducing the first copper refining slag. Applicants have determined that the addition of the reducing agent contributes to achieving the desired chemical reduction. Applicants have found that the first reducing agent may be a gas, such as methane or natural gas, but may also be a solid or a liquid, such as carbon, a hydrocarbon, even aluminum or iron.
In an embodiment of the method according to the present invention, the first reducing agent comprises a metal, and the first reducing agent is preferably a metal which, under the conditions of the method, has a higher affinity for oxygen than tin, lead, copper and nickel , preferably iron metal, more preferably scrap iron. Applicants preferably use iron, preferably scrap iron, as the reducing agent, due to their high availability at economically attractive conditions. Applicants have found that the addition of the solid reducing agents may have the additional positive effect that the furnace requires less additional heating to maintain or reach its desired temperature. The applicants have found that this positive effect can be so great that additional heating, by burning a fuel with the aid of air and / or oxygen, can hardly be necessary to reach the desired temperature. The applicants have furthermore determined that step c) may further be positively impacted by the addition of silica, as explained elsewhere in this document.
In an embodiment of the method according to the present invention in step i) at least a part of the second copper refining slag is added to the first liquid bath and / or to step d),
BE2018 / 5875, preferably the majority of the second copper refining slag and more preferably the entire second copper refining slag.
Applicants have found that the composition of the second copper refining slag is extremely suitable for being added to the first liquid bath. Applicants therefore prefer to add the complete second copper refining slag into the first liquid bath. The stream is suitable in the first place because the second copper refining slag is already relatively rich in the intended valuable metal tin and lead, but also contains significant amounts of copper, which can function downstream as an extractant for non-copper metals such as tin and lead. Secondly, the second copper refining slag contains only small amounts of metals that have a higher affinity for oxygen under the conditions of the process than tin and / or lead, more particularly metals that are less desirable in the final purified metal products copper, tin and / or lead, which will have to be removed from the process as part of a spent snail. Because the second copper refining slag is relatively poor in such metals, the addition of this slag in the first liquid bath does not lead to the ingestion of a large useless amount of furnace volume in one of the downstream steps
In an embodiment of the method according to the present invention, the first spent slag from step c) comprises in total at most 20.0% by weight and more preferably at most 18% by weight of copper, tin and lead together, preferably in total at least at most 15% by weight, more preferably at most 12% by weight, even more preferably at most 9.0% by weight, even more preferably at most 7.0% by weight, preferably at most 5.0 % by weight, more preferably at most 4.0% by weight, even more preferably at most 3.0% by weight, even more preferably at most 2.0% by weight, preferably at most 1.5 % by weight and more preferably at most 1.10% by weight of copper, tin and lead together.
In an embodiment of the method according to the present invention, the first spent slag from step c) comprises at most 7.0% by weight of copper, preferably at most 5.0% by weight, with more
BE2018 / 5875 preferably at most 3.0% by weight, even more preferably at most 2.0% by weight, even more preferably at most 1.50% by weight, preferably at most 1.00% by weight , more preferably at most 0.75% by weight, even more preferably at most 0.60% by weight, even more preferably at most 0.50% by weight, preferably at most 0.40% by weight buyer.
In an embodiment of the method according to the present invention, the first spent slag from step c) comprises at most 7.0% by weight of tin, preferably at most 5.0% by weight, more preferably at most 3.0% by weight. %, even more preferably at most 2.0% by weight, even more preferably at most 1.50% by weight, preferably at most 1.00% by weight, more preferably at most 0.75% by weight. %, even more preferably at most 0.60% by weight, even more preferably at most 0.50% by weight, preferably at most 0.40% by weight, more preferably at most 0.30% by weight. % tin.
In an embodiment of the method according to the present invention, the first spent slag from step c) comprises at most 7.0% by weight of lead, preferably at most 5.0% by weight, more preferably at most 3.0% by weight. %, even more preferably at most 2.0% by weight, even more preferably at most 1.50% by weight, preferably at most 1.00% by weight, more preferably at most 0.75% by weight. %, even more preferably at most 0.60% by weight, even more preferably at most 0.50% by weight, preferably at most 0.40% by weight of lead.
The specified upper limits for the presence of copper, tin, lead and of the three metals together in the first spent slag, entail for each individual the advantage that the economic value of the quantities of the three target metals leaving the process with the first used up snail from step c) is kept under control. This reduces the need or desirability of providing additional process steps on the first spent snail before it can be disposed of, and thus brings the advantage that fewer, or possibly no further processing steps are needed before the first spent snail can be removed, or before the snail as
BE2018 / 5875 is considered acceptable in an economically more attractive application or end use.
In the first spent slag of the method according to the present invention comprising step c), most of the elements are collected which under the conditions of the method have a higher affinity for oxygen than tin and / or lead and / or copper and / or nickel. This applies in particular to metals such as zinc, chromium, manganese, vanadium, titanium, iron, aluminum, sodium, potassium, calcium and other alkaline earth alkaline metals, but also to other elements such as silicon or phosphorus.
In an embodiment of the method according to the present invention, the temperature of the slag in step b) and / or in step c) is at least 1000 ° C, preferably at least 1020 ° C, more preferably at least 1040 ° C, even more preferably at least 1060 ° C, preferably at least 1080 ° C, more preferably at least 1100 ° C, even more preferably at least 1110 ° C, preferably at least 1120 ° C, more preferably at least 1130 ° C, even more preferably at least 1140 ° C, preferably at least 1150 ° C. Applicants have found that the separation between the metal phase and the slag phase is better when the temperature of the slag corresponds to the prescribed limit value, and is preferably above the prescribed limit value. Without wishing to be bound by this theory, the applicants believe that the higher temperature produces a better separation, at least because the viscosity of the slag is lower at higher temperatures. A lower viscosity of the slag enables the bubbles of heavier metals to combine more rapidly into larger bubbles and to sink faster through the slag phase until they reach the underlying metal phase and can be combined with it. A higher temperature also entails the advantage of faster reaction kinetics, such that a desired equilibrium state can be achieved more quickly.
However, the applicants also believe that the balance between the metal and slag phase is influenced by the temperature. A higher temperature usually reduces the differences between
BE2018 / 5875 different metals with regard to their affinity for oxygen under the conditions of the process. Applicants therefore prefer to limit the oven temperature in step b) and / or c) to at most 1300 ° C, preferably at most 1250 ° C, more preferably at most 1200 ° C. Applicants prefer to apply this limit to most, if not all, steps in the method of the present invention in which a phase separation is performed between at least two liquid phases, usually a supernatant slag phase and an underlying metal phase.
In an embodiment of the method according to the present invention, additional raw materials are added as fresh feed to step b). Applicants prefer to add raw material containing solid metal because the melting of this solid metal is capable of absorbing some of the reaction heat and helps to keep the temperature of the furnace within the preferred range. Applicants prefer to use raw materials rich in copper for this purpose and which may contain at least small amounts of Sn and / or Pb. The preferred temperature range is defined by a lower limit below which the viscosity of at least one of the liquid phases becomes too high for the operation of the oven. The preferred temperature range is defined by an upper limit above which the volatility of valuable metals, in particular tin and / or lead, becomes too high and the recovery of these metals as part of the furnace dust becomes too difficult, complicated and expensive. .
At the high temperatures in a non-ferrous metal smelting or refining step, the metals and metal oxides both occur in the liquid, molten state. The metal oxides generally have a lower density than the metals and form a separate so-called "slag" phase that comes to surface as the supernatant liquid phase on the molten metal phase. The metal oxides can thus be separated from the molten metal phase by gravity as a separate liquid slag phase. Silicon dioxide, usually in the form of normal sand, can
BE2018 / 5875 are added as a so-called "flux material", i.e. as a slag diluent and / or for improving the fluidity of the slag such that it separates more easily from the metal phase and is easier to handle. The silicon dioxide is also able to bind certain elements, and thereby also influences the urge of that element to become part of the slag phase instead of the metal phase. Applicants have found that the addition of silica is a highly desirable element of the process for many of the steps that form part of the process of the present invention in which a slag phase and a metal phase are to be separated from each other because the silica is in many conditions contributes to altering the balance between the metal phase and the slag phase in favor of the desired separation with regard to the metals which are desired in the metal phase and the metals which preferably remain in the slag phase. The applicants have further established that when the slag contains iron and is removed from the furnace and pelletized by contacting the hot liquid slag with water, the addition of silica may eliminate the risk of the iron being in a form that acts as a catalyst for the splitting of water and thereby the formation of hydrogen gas, which poses an explosion hazard. Silicon dioxide also increases the activity of any tin present in the slag, whereby a portion of the SnO 2 is reduced to Sn metal, whereby this Sn will pass to the metal phase. This latter mechanism lowers the amount of Sn remaining in the slag for the same underlying metal composition.
Under the pyrometallurgy operating conditions, various chemical reactions take place between the various metals and oxides in the furnace. The metals with a higher affinity for oxygen are more easily oxidized, and those oxides tend to pass to the slag phase, while the metals with a lower affinity for oxygen, if present as oxides, rapidly reduce to return to their metal state, and these metals tend to transition to the liquid metal phase. If sufficient contact area and time are provided, one will be added
BE2018 / 5875 steady state between the metal phase in which the metals with a lower affinity for oxygen collect under the conditions of the process, and the slag phase, in which the metals with a higher affinity for oxygen collect under the conditions of the process in the form of their oxides.
Metals such as sodium (Na), potassium (K), calcium (Ca) and silicon (Si) have an extremely high affinity for oxygen and will be collected almost exclusively in the slag phase. Metals such as silver (Ag), gold (Au) and other precious metals have an extremely low affinity for oxygen, and are collected almost exclusively in the metal phase. Most other metals usually exhibit "between" these two extremes, and their tendencies can moreover be influenced by the presence of other elements or substances, or possibly their relative absence.
The metals of interest for this invention exhibit, under the typical furnace conditions of non-ferrous metal refining, affinities for oxygen, and will tend to divide between the metal and the slag phase. From lower to higher affinity for oxygen, and consequently from a relatively high affinity to a lower affinity for the metal phase, the arrangement of these metals can be roughly presented as follows: Au> Ag >> Bi / Cu> Ni> As> Sb> Pb> Sn >> Fe> Zn> Si> Al> Mg> Ca. For convenience, this can be called a ranking of the metals from the more noble to the less noble, but this qualification must be linked to the specific conditions and conditions of pyrometallurgical non-ferrous metal processes, and can fail when exported to other fields. The relative position of specific metals in this list can be influenced inter alia by the presence or absence of other elements in the furnace, such as silicon.
The equilibrium distribution of a metal between the metal and slag phase can also be influenced by the addition of oxygen and / or oxygen scavenging materials (or reducing agents) to the liquid bath in the furnace.
BE2018 / 5875
Due to the addition of oxygen, some of the metals in the metal phase will be converted to their oxidized form, after which this oxide will then transfer to the slag phase. The metals in the metal phase that have a high affinity for oxygen will show a stronger tendency to undergo this conversion and change phase. Their distribution in equilibrium between the metal and slag phase may therefore be more subject to change.
The opposite can be accomplished by the addition of oxygen scavenging materials. Suitable oxygen consumers can be, for example, carbon and / or hydrogen, in whatever form, such as in organic materials, for example wood, or other combustible substances, such as natural gas. Carbon and hydrogen will easily oxidize ("burn") and be converted to H2O and / or CO / CO2, components that easily leave the liquid bath and carry its oxygen content from the bath. But metals such as Si, Fe, Al, Zn and / or Ca are also suitable reducing agents. Iron (Fe) and / or aluminum (Al) are of particular importance because of their easy availability. By oxidizing, these components will reduce some of the metals in the slag phase from their oxidized state to their metal state, and these metals will then transfer to the metal phase. Now it is the metals in the slag phase with a lower affinity for oxygen that will be more inclined to undergo this reduction reaction and to carry out the transition in the reverse direction.
In a smelting furnace step, one of the goals is to reduce oxides of valuable non-ferrous metals that are introduced with the feed to their corresponding reduced metals. The direction and speed of the reactions that take place in the smelting furnace step can also be controlled by checking the nature of the atmosphere in the furnace. Alternatively, or additionally, oxygen donating material or oxygen scavenging material may be added to the smelting furnace.
An extremely suitable oxygen scavenging material for such activities is iron metal, with preference being given
BE2018 / 5875 usually goes to scrap iron. Under the typical operating conditions, the iron will react with hot oxides, silicates and the other compounds of metals with a lower affinity for oxygen than iron, to form a melt containing the latter metals in elemental form. Typical responses include:
MeO + Fe FeO + Me + heat (MeO) xSiO2 + x Fe (FeO) xSiO2 + x Me + heat
The temperature of the bath remains high due to the exothermic heat of reaction and the heat of combustion. The temperature can easily be kept within a range in which the slag remains liquid and the volatilization of lead and / or tin remains limited.
Each of the reduction reactions that take place in the melting furnace forms a balance. Therefore, the conversion induced by each reaction is limited by the equilibrium states defined in equations such as the following:
[FeO] [Me]
K1 = ------------------------ [MeO] [Fe] [(FeO) xSiO2] [Me] ^x
K2 = ------------------------------------ [(MeO) xSiO2] [Fe] ^x
The parameters in these formulas represent the activities of the stated chemical components under the working conditions, which often involve the multiplication of the concentration of the component times the activity coefficient of the component under the working conditions, the latter not always being equal to 1.0 or equal for different components. Applicants have found that the activity coefficients can be influenced by the presence of other chemical compounds, such as so-called flux compounds, which are sometimes referred to as slag formers, in particular by the addition of silicon dioxide.
In the case that Me is copper, K1 and K2 are high at normal reaction temperatures and the reduction of copper compounds occurs
BE2018 / 5875 so that it is almost complete. In the case of lead and tin, K1 and K2 are both relatively low, but the copper in the metal phase extracts lead and tin in metal form from the slag reaction zone, thereby reducing the activities of these metals in the slag and the reduction of combined lead and tin is driven to completion.
The vapor pressure of zinc is relatively high at the typical reaction temperature and a large proportion of zinc, unlike lead and tin, can be easily evaporated from the furnace. Zinc vapors leaving the oven are oxidized by air, which can be blown in, for example, between the oven access and the hood and / or the exhaust pipe. The resulting zinc oxide dust is condensed and collected by conventional dust collection systems.
Preferably, the copper content, the tin content and the lead content of the slag in the smelting furnace are each reduced to 0.5% by weight or less. To this end, the metal phase must contain sufficient copper to act as the solvent to extract the lead and tin present from the slag. For the same reason, applicants also prefer that the concentration of copper in the black copper supplied to the process of the present invention is above the lower limit specified elsewhere in this document.
In one embodiment of the method of the present invention, the black copper composition or the black copper used in some of the process steps meets at least one of the following conditions, most preferably all of the following conditions:
· Comprising at least 51% by weight of copper, • including at most 96.9% by weight of copper, • covering at least 0.1% by weight of nickel, • covering at most 4.0% by weight % nickel, · comprising at least 1.5% by weight of tin, · comprising at most 15% by weight of tin, · comprising at least 1.5% by weight of lead, · comprising at most 25% by weight of lead,
BE2018 / 5875 · comprising at most 3.5% by weight of iron, and · including at most 8.0% by weight of zinc.
In one embodiment of the method of the present invention, the black copper comprises at most 96.9% by weight or more preferably at most 96.5% by weight of copper, preferably at most 96.0% by weight, more preferably at least at most 95.0% by weight, even more preferably at most 90.0% by weight, even more preferably at most 85.0% by weight, preferably at most 83.0% by weight, more preferably at most at most 81.0% by weight, even more preferably at most 80.0% by weight, even more preferably at less than 80.0% by weight and preferably at most 79.0% by weight of copper. This entails the additional advantage that the upstream process for producing the black copper can incorporate raw materials that comprise much more metals than copper. It is particularly advantageous to accept more tin and / or lead in the production of the black copper, and these larger amounts of tin and / or lead can easily be processed into a larger amount of crude soldering co-product, a product with a relatively high economic value .
In one embodiment of the method of the present invention, the black copper comprises at least 51% by weight of copper, preferably at least 52% by weight, more preferably at least 53% by weight, even more preferably at least 54% by weight. %, even more preferably at least 55% by weight, preferably at least 57% by weight, more preferably at least 59% by weight, even more preferably at least 60% by weight, even more preferably at least at least 62% by weight, preferably at least 64% by weight, more preferably at least 66% by weight, even more preferably at least 68% by weight, even more preferably at least 70% by weight, preferably at least 71% by weight, more preferably at least 72% by weight, even more preferably at least 73% by weight, even more preferably at least 74% by weight, preferably at least 75% by weight, with more preferably at least
77.5% by weight, even more preferably at least 80% by weight, even more preferably at least 85% by weight of copper.
BE2018 / 5875
This entails the advantage that a stock refining step as provided in U.S. Pat. No. 3,682,623 for upgrading a black copper containing 75-80% by weight copper to about 85% by weight copper or higher (85.12% by weight) copper in the Example, Table VI) can be omitted.
The applicants have further established that the process as a whole is more workable and efficient, and generally produces more of the high-quality products, if the concentration of copper in the black copper remains within the prescribed lower limit. With a lower concentration of copper in the black copper, other elements complete the balance. That is quite acceptable and often even desirable if they are valuable metals that complement the balance, such as lead, but even more interesting if they also include tin. These metals use chemicals during every oxidation and / or reduction step, but ultimately a large part of them ends up in a high-quality product stream. On the other hand, if lower value metals or elements inevitably end up in one of the used up slags that form the balance, then the lower copper concentration is rather disadvantageous because these metals and / or elements use chemicals in the oxidation steps as part of the copper refining steps, and / or other chemicals, in one of the downstream reduction steps, such as step c) of the method of the present invention. Moreover, these low value metals or elements take up volume in the furnace, and therefore their presence requires larger furnaces and therefore higher investment costs. Within a given format of available equipment, the presence of these metals or elements reinforces the restrictions on introducing higher value raw materials into any of the process steps, such as those with high concentrations of copper, tin and / or lead. The black copper composition is typically an intermediate produced by another pyrometallurgical process step, i.e., a smelting furnace step. A smelting furnace step yields a molten metal product, the so-called "black copper", and a liquid slag of mainly metal oxides,
BE2018 / 5875 usually in the presence of significant amounts of silica. Applicants prefer to obtain in a smelting furnace step a black copper product containing at least the minimum prescribed amount of copper, because the high presence of copper acts as an extractant for other valuable metals, for example tin and lead. Therefore, by keeping the copper concentration in the black copper composition above the stated limit value, a higher recovery is achieved of these other valuable metals present in the black copper composition, rather than losing these valuable metals as part of the smelting furnace slag, where these metals usually have little to no value and can even form a load.
In an embodiment of the method of the present invention, the black copper comprises at least 1.5% by weight of tin, more preferably at least 2.0% by weight, even more preferably at least
2.5% by weight, even more preferably at least 3.0% by weight, preferably at least 3.5% by weight, more preferably at least 3.75% by weight, even more preferably at least 4, 0% by weight, even more preferably at least
4.5% by weight, preferably at least 5.0% by weight, more preferably at least
5.5% by weight, even more preferably at least 6.0% by weight, even more preferably at least 6.5% by weight, preferably at least 7.0% by weight, more preferably at least 7, 5 wt%, even more preferably at least 8.0 wt%, even more preferably at least 8.5 wt%, preferably at least 9.0 wt%, more preferably at least 9, 5% by weight, even more preferably at least 10.0% by weight, even more preferably at least 11.0% by weight of tin. Tin is a very valuable metal that is relatively scarce in the form of a product with a higher purity. Applicants therefore prefer to produce as much tin as their method can handle. In addition, applicants prefer to recover this tin from raw materials of low economic value, in which tin is usually present in low concentrations. Such low value materials often contain large amounts of elements that are difficult to process in a pyrometallurgical copper refining process, and are
BE2018 / 5875 therefore usually first processed in a smelting furnace step. The tin in those low value materials, therefore, ends primarily as part of the black copper composition. Applicants prefer to produce as much tin as possible from such low value materials, and therefore prefer that the black copper composition of the process of the present invention contains as much tin as possible within the other limitations of the process .
In an embodiment of the method of the present invention, the black copper comprises at least 1.5% by weight of lead, more preferably at least 2.0% by weight, even more preferably at least
2.5% by weight, even more preferably at least 3.0% by weight, preferably at least 3.5% by weight, more preferably at least 3.75% by weight, even more preferably at least 4.0% by weight, even more preferably at least
4.5% by weight, preferably at least 5.0% by weight, more preferably at least
5.5% by weight, even more preferably at least 6.0% by weight, even more preferably at least 7.0% by weight, preferably at least 8.0% by weight, more preferably at least 9.0% by weight, even more preferably at least 10.0% by weight, even more preferably at least 11.0% by weight, preferably at least 12.0% by weight, more preferably at least 13.0% by weight, even more preferably at least 14.0% by weight, even more preferably at least 15.0% by weight of lead.
Lead is also a valuable metal. In addition, the presence of lead promotes the recovery of the even more valuable tin metal because it behaves similarly to tin and ends up in the same process streams, forming a mixture called "solder", and the resulting solder streams having a higher density and thereby be easier to separate from lower density liquid streams such as slag, or solid streams such as scratch. Applicants therefore prefer to provide a considerable amount of lead in their process. In addition, the applicants prefer to recover this lead from raw materials with low economic value, in which lead is usually present in low concentrations. Such low value materials often contain large ones
BE2018 / 5875 amounts of elements that are difficult to process in a pyrometallurgical copper refining process, and are therefore usually first processed in a smelting furnace step. The lead in those low-value raw materials therefore mainly ends as part of the composition of black copper. Applicants prefer to obtain as much lead as possible from such low value materials, and therefore prefer that the black copper composition of the process of the present invention contains as much lead as possible within the other limitations of the process.
A higher presence of tin and / or lead in the black copper brings with it the advantage that the raw materials containing this tin and / or lead can be processed in a smelting furnace step, a step that is very tolerant of other impurities, much more then the typical steps performed as part of a copper refining process, including any steps associated with the co-production of other non-ferrous metals such as tin and / or lead. These acceptable raw materials are therefore generally of a much lower quality and therefore also of a lower economic value. Most of the tin and / or lead in the black copper of the process of the present invention ends up in a coarse soldering co-product, which is a product with relatively high economic value. The economic upgrading of the tin and / or lead in the black copper supplied to the process of the present invention is therefore generally much higher than the same amount that is introduced as part of a much more concentrated raw material that may be directly acceptable in a of the steps in the copper refining process, including the frames.
Applicants therefore prefer to provide larger amounts of tin and / or lead in the black copper, because that entails the advantage that within a limited amount of these metals to be produced, due to equipment limitations, more of these metals are recovered from low value raw materials, and therefore more of these metals can become
BE2018 / 5875 recovered with a high economic upgrade of their low value in the raw material and their high economic value in the end product.
In one embodiment of the process of the present invention, the black copper comprises at most 15.0% by weight of tin, preferably at most 14.0% by weight, more preferably at most 13.0% by weight, with even more preferably at most 12.0% by weight, even more preferably at most 11.0% by weight, preferably at most 10.0% by weight, more preferably at most 9.0% by weight, even more preferably at most 8.0% by weight, even more preferably at most 7.0% by weight, preferably at most 6.0% by weight of tin. Applicants have found that limiting the concentration of tin in the black copper composition to the specified upper limits entails the advantage that the black copper composition leaves sufficient room for other metals and elements. As stated above, a presence of copper is very advantageous in the upstream smelting furnace step, and that also applies to the presence of lead. Applicants therefore prefer to keep the concentration of tin within the specified upper limit.
In one embodiment of the method of the present invention, the black copper comprises at most 25.0% by weight of lead, preferably at most 24.0% by weight, more preferably at most 23.0% by weight, with even more preferably at most 22.0% by weight, even more preferably at most 21.0% by weight, preferably at most 20.0% by weight, more preferably at most 19.0% by weight, even more preferably at most 18.0% by weight, even more preferably at most 17.0% by weight, preferably at most 16.0% by weight, more preferably at most 15.0% by weight, even more more preferably at most 14.0% by weight, even more preferably at most 13.0% by weight, even more preferably at most 12.0% by weight, preferably at most 11.0% by weight, with more preferably at most 10.0% by weight, even more preferably at most 9.0% by weight, even more preferably at most 8.0% by weight, preferably at most 7.0% by weight of lead. Applicants have found that limiting the concentration of lead in the composition of black copper to the
BE2018 / 5875 specified upper limits entails the advantage that sufficient space is left in the black copper composition for other metals and elements. As stated above, a presence of copper is very advantageous in the upstream smelting furnace step, and also the presence of significant amounts of tin is highly desirable. Applicants therefore prefer to keep the lead concentration within the specified upper limit.
The applicants have established that the presence of excessive amounts of tin and / or lead in the black copper has an influence on any possible separation step between copper (and nickel) on the one hand, and tin and lead on the other. The separation is less clear and, as a rule, more tin and / or lead remains with the copper. Even if the copper stream is at least partially recycled, this leads to larger amounts of tin and / or lead being in circulation in the process and taking up furnace volume. However, even if the copper stream from that separation, or a part thereof, is removed from the process, the larger amounts of tin and / or lead in that stream represent an additional burden for its downstream processing.
In an embodiment of the method of the present invention, the black copper comprises at least 0.1% by weight and at most 4.0% by weight of nickel (Ni). The black copper feed to step b) preferably comprises at least 0.2% by weight of nickel, more preferably at least 0.3% by weight, even more preferably at least 0.4% by weight, even more more preferably at least 0.5 wt%, preferably at least 0.75 wt%, more preferably at least 1.00 wt% nickel.
Nickel is a metal that is present in many raw materials that contain copper, tin and / or lead, and it is also present in many alloys that contain or are even based on iron. Nickel shows an affinity for oxygen lower than that of tin and / or lead under the conditions in the furnace, and which is close to and slightly higher than that of copper. It is therefore a metal that is difficult to separate from copper due to pyrometallurgy. In US 3,682,623, most of the nickel contained in the pre-refined black copper (Table VI, 541.8 kg) disappears from the
BE2018 / 5875 process as an impurity in the refined copper product (Table XII, 300 kg), which was cast into anodes (col. 19, lines 61-62). A small amount of the nickel finds its way to the lead / tin metal product (Table XV, 110 kg). The process involves a substantial black copper recycling stream, in which the presence of nickel appears to increase with each cycle (Table XIV, 630 kg, compared to Table VI, 500 kg). Applicants have found that nickel in the copper anodes is a disturbing element in the downstream electrofining step. Under the conditions of the electro refining process, the nickel dissolves in the electrolyte but does not deposit on the cathode. As a result, it may accumulate in the electrolyte and may lead to the precipitation of nickel salts when their solubility limit is exceeded. But even at lower levels, the nickel can already lead to anode passivation due to a possible build-up of a nickel concentration gradient on the anode surface. The method according to US 3,682,623 is thus limited in its ability to process nickel. The melting step in US 3,682,623 can therefore only take up a fairly limited amount of raw materials that contain significant amounts of nickel.
Applicants have now determined that the method of the present invention is capable of incorporating much larger amounts of nickel, for example, as part of the black copper from an upstream smelting furnace step. This higher tolerance for nickel provides for the process of the present invention, and for any process steps carried out upstream, a wider acceptance window with respect to raw materials. The method of the present invention, and according to any of its upstream process steps, can thus incorporate raw materials that may not accept alternative methods known in the art, or accept only in very limited quantities, and thus may be more readily available to more economically attractive conditions.
Despite the higher tolerance for nickel, the applicants have also found that the method of the present invention may be able to produce a high-quality anode copper product.
BE2018 / 5875 produce that is richer in copper and contains less nickel compared to the anode copper produced in US 3,682,623.
In an embodiment of the method according to the present invention, the black copper comprises at most 3.5% by weight of iron, preferably at most 3.0% by weight, more preferably at most
2.5% by weight, even more preferably at most 2.0% by weight, even more preferably at most 1.80% by weight, preferably at most 1.60% by weight of iron.
In an embodiment of the method of the present invention, the black copper comprises at most 8.0% by weight of zinc, preferably at most 7.5% by weight, more preferably at most 7.0% by weight, with even more preferably at most 6.5% by weight, even more preferably at most 6.0% by weight, preferably at most 5.5% by weight, more preferably at most 5.0% by weight, even more preferably at most 4.7% by weight of zinc.
Applicants have determined that it is advisable to keep the iron and / or zinc concentrations within the specified limits. These metals are usually oxidized in the copper refining steps, where they use consumables. Zinc is quickly reduced in each of the reduction steps of the process, and therefore consumes additives there as well. In addition, these metal take up oven volume. For these reasons, applicants wish to limit these metals to the respective concentrations indicated.
In one embodiment, the method of the present invention further comprises the following step:
e) partially reducing the first solder refining slag, thereby forming a first raw solder metal composition and a second solder refining slag, followed by separating the second solder refining slag from the first raw solder metal composition.
This step e) produces a raw solder current that is rich in tin and / or lead, and which also comprises the majority of the relatively small amounts of copper and / or nickel that were entrained in the first
BE2018 / 5875 solder refining slag. The first raw solder current is suitable for further processing for further enrichment in tin and / or lead, for example by treatment with silicon metal as described in patent DE 102012005401 A1. Alternatively, or additionally, this crude solder current, optionally after an enrichment step for increasing the tin and / or lead content, may be further updated as described in WO 2018/060202 A1 or the like, and then subjected to a distillation and recovery of the tin and / or lead as high purity metal products, as described in the same document.
Applicants have found that the reduction in step e) can be carried out at least in part by adding a suitable metal stream (second reducing agent), ie by adding a metal composition containing metals that have a higher affinity under the conditions of the process for oxygen then tin and / or lead, such as zinc, silicon, magnesium, iron, calcium or aluminum. This metal stream preferably also additionally contains tin and / or lead, and may optionally also contain an amount of antimony and / or arsenic. This additional antimony, tin and / or lead quickly ends up in the first raw solder metal composition from step e) and can easily be recovered downstream as part of a high-quality purified metal product. The added metal stream preferably contains only small amounts of nickel and / or copper, ie metals that are likely to become part of the first raw solder metal composition from step e) but that may entail additional process loads and operating costs, such as additional consumption of silicon when a step of silicon treatment is provided downstream in the refining of the first raw solder metal composition. Iron is also preferably present in only limited quantities, because not all of the added iron can end up in the slag phase, but can also leave step e) together with the first raw solder metal composition, and increase the process loads downstream.
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Applicants have found that in step e) the recovery of the solder metals in the first raw solder metal composition can be advantageously high, and the entrainment of tin and / or lead, but also of copper and / or nickel, advantageously low in the second solder refining slag can be had.
In one embodiment, the method of the present invention further comprises the following step:
f) partially reducing the second solder refining slag, thereby forming a second lead-tin-based metal composition and a second spent slag, followed by separating the second spent slag from the second lead-tin-based metal composition.
Applicants have determined that it is advantageous to provide the additional reduction step f) downstream of the raw soldering production step e), in particular a reduction step on the second solder refining slag recovered from that step e). Applicants have determined that more valuable metals can be withdrawn from this second solder refining slag by step f), which makes the remaining slag even more suitable for use in a valuable end application, and / or for discharging this slag as spent slag. The applicants have further established that the additional reduction step f) is also able to lower the leachable metals content, such as lead, in the slag to sufficiently low levels for the slag remaining from step f) to be further used as valuable material, or could be disposed of responsibly, with a very limited number of additional treatment steps, and possibly even without further processing steps, for reducing the concentration of sensitive metals such as lead and / or zinc.
In one embodiment, the method of the present invention further comprises adding a first copper-containing material to step f), preferably prior to reducing the second solder refining slag.
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The applicants have found that the addition of copper in reduction step f) brings a considerable advantage because the copper can act as an excellent extraction agent for any other valuable metals remaining in the second solder refining slag remaining after step e), and that this advantageous extraction step can be carried out without loss of significant amounts of copper in the second spent slag produced in step f).
The applicants have further established that the copper-containing fresh feed that can be added in step f) can contain significant amounts of other valuable metals, in particular of zinc, nickel, tin and / or lead. The applicants have established that, provided that sufficient copper is made available, the losses of in particular tin and / or lead in the second spent slag can be kept very low and therefore do not entail any risk for possible further use or trajectory. of this second spent snail, nor an economically significant loss of valuable metals.
Applicants have determined that a wide variety of materials are suitable as a copper-containing fresh feed to step f). However, the applicants prefer that the copper-containing fresh feed to step f) comprises only small amounts, and preferably little to no combustible substances, ie substances that oxidize easily under the conditions of the process, for example organic materials such as plastics and / or or hydrocarbons, residues of fuel or oil, etc., such that the temperature in step f) remains easily controllable.
In an embodiment of the method according to the present invention, the first copper-containing fresh feed comprises black copper and / or spent or rejected copper anode material.
Applicants have found that in step f) a substantial amount of black copper, the composition of which is similar to that of the black copper provided in step a), can be
BE2018 / 5875 added in step f) for extracting more valuable metals from the second solder refining slag from step e) without excessive loss of extra valuable metals in the second spent slag from step f). Applicants have found that the amounts of such black copper from an upstream smelting furnace step acceptable in step f) are very substantial, even on the order of the amount of black copper supplied in step a) as feed for step b). Applicants have found that incorporating step f) into the process of the present invention considerably increases the capacity to process smelting furnace type black copper, and therefore to process larger amounts of lower quality raw materials in which valuable metals in low grade form are provided, and therefore provide a high potential for upgrading. Applicants have found that this way of performing step f) entails the additional advantage that a substantial portion of the black copper can be processed from the upstream smelting furnace step without having all of that black copper by at least the first step b) of the copper refining sequence has to go. Any metals present in the black copper feed to step f) that have a higher affinity for oxygen than copper under the conditions of the process are most likely already removed before the copper from this fresh black copper feed to step f) at one or can find its way into step b), and then go through the copper refining process sequence of steps b), h) and j), and end up in the anode-quality copper product.
Applicants have also determined that step f) is also extremely suitable for introducing spent and / or rejected copper anode material. The production of high-quality copper generally involves an electrolysis step, in which copper dissolves into the electrolyte from an anode and is deposited again on a cathode. The anode is generally not completely used up and the anode is removed from the electrolysis bath as spent copper anode material before its last copper is dissolved. Applicants have found that step f) is extremely
BE2018 / 5875 is suitable for introducing such spent copper anode material. Copper anodes for such a copper electrolysis step are typically cast by casting a suitable amount of anode grade molten copper into a mold and allowing the copper to cure after cooling. For copper electrolysis to function properly, the anodes must meet fairly strict dimensions and shape requirements. Anodes that do not comply with this are preferably not used, but form discarded copper anode material. Applicants have determined that step f) is also extremely suitable for introducing such rejected copper anode material.
Applicants prefer to use the spent and / or rejected copper anode material as a solid, with little to no preheating. This entails the advantage that the melting of this material consumes at least a part of the heat of reaction generated by the chemical reactions that take place in step f).
In an embodiment of the method according to the present invention, step f) comprises adding a third reducing agent to step f), i.e. the step of reducing the second solder refining slag.
Applicants have found that the third reducing agent makes it possible to direct the result of reduction step f) towards the desired separation of valuable metals in the second lead-tin-based metal composition and to leave metals to be rejected in the second used up snail. Applicants have found that the third reducing agent can be a gas, such as methane or natural gas, but can also be a solid or a liquid, such as carbon, a hydrocarbon, even aluminum or iron.
In an embodiment of the method of the present invention, the third reducing agent comprises a metal, and the third reducing agent is preferably a metal which has a higher affinity for oxygen under the conditions of the method than tin, lead, copper and nickel , preferably iron metal, more preferably
BE2018 / 5875 scrap iron. Applicants preferably use iron, preferably scrap iron, as the reducing agent, due to their high availability at economically attractive conditions. Applicants have found that the addition of the solid reducing agent may entail the additional advantage that the furnace requires less additional heating to maintain or reach its desired temperature. Applicants have found that this positive effect can be large enough for additional heating by burning a fuel with the aid of air and / or oxygen to remain limited, or even hardly necessary to achieve the desired temperature. The applicants have furthermore determined that step f) may furthermore be positively effected by the addition of silica, as explained elsewhere in this document.
Applicants prefer to add to step f) an amount of a third reducing agent that is rich in iron, preferably as a multi-metal material, because such multi-metal material is more readily available under more favorable conditions than higher purity tin, copper of higher purity or iron of higher purity. Another suitable material could be electric motors, preferably such motors after use, because of their high iron content for the cores and copper for the windings. Applicants have found that the copper and / or tin can easily be kept in the metal phase and prevented from passing into the slag phase, while the iron present in this copper-containing fresh feed easily passes to the slag phase as iron oxide while contributing to the chemical reduction of other metals that have a lower affinity for oxygen than iron under the conditions of the process.
In an embodiment of the method according to the present invention, the method further comprises the step of:
g) recycling at least a portion of the second lead-tin-based metal composition to step c), preferably the majority, if not all, of the second metal composition to
BE2018 / 5875 lead-tin base is added to step c), and preferably before reducing the first copper refining slag.
Applicants have found that the valuable metals in the second lead-tin-based metal composition from step f) can be easily recovered by adding this composition to step c). The metals in the second lead-tin-based metal composition with a higher affinity for oxygen under the conditions of the process oxidize easily and lead to a reduction of those metals fed to step c) which have a lower affinity for oxygen under the same conditions . The presence in step c) of the additional metals from step f) leads to a partial reduction of the metals present in the first copper refining slag as oxides. Consequently, more valuable metals, such as Cu, Ni, Sn, Pb, Sb, As, pass into the metal phase of step c), and more metals to be rejected, such as Fe, Si, and Al, pass into the spent slag produced. in step c). The addition of this second lead-tin-based metal composition in step c) thereby improves the desired separation of the other base materials to step c), in combination with obtaining a desired separation of the metals recovered from step f).
In an embodiment of the method according to the present invention, step e) comprises adding a second reducing agent to step e), preferably to the first solder refining slag prior to reducing the first solder refining slag. The applicants have further determined that to perform the reduction in step e), in addition to the metal stream that can be added in step e) or alternatively, a reducing agent can be added to step e). Applicants have determined that the addition of the reducing agent contributes to achieving the desired chemical reduction. Applicants have found that the second reducing agent can be a gas, such as methane or natural gas, but can also be a solid or a liquid, such as carbon, a hydrocarbon, even aluminum or iron.
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In an embodiment of the method according to the present invention, the second reducing agent comprises a metal, and the second reducing agent is preferably a metal which, under the conditions of the method, has a higher affinity for oxygen than tin, lead, copper and nickel wherein the second reducing agent preferably comprises iron metal, more preferably scrap iron. Applicants preferably use iron, preferably scrap iron, as the reducing agent, due to their high availability at economically attractive conditions. Applicants have found that the addition of the solid reducing agents may have the additional positive effect that the furnace requires less additional heating to maintain or reach its desired temperature. The applicants have found that this positive effect may be large enough for additional heating by burning a fuel with the aid of air and / or oxygen to remain limited, or even hardly necessary to reach the desired temperature. The applicants have furthermore determined that step e) may furthermore be positively effected by the addition of silica, as explained elsewhere in this document.
In an embodiment of the method according to the present invention comprising step e), a first Pb and / or Sn containing fresh feed is added to step e), preferably to the first solder refining slag before reducing the first solder refining slag, the first Pb and / or Sn-containing fresh feed preferably comprises scratch, and more preferably is scratch, which is obtained from downstream processing of concentrated streams of Pb and / or Sn.
Applicants have found that step e) is also a very suitable location in the process for adding materials that are rich in tin and / or lead, but low in copper and nickel, but that may contain metals which under the conditions of the process have a higher affinity for oxygen than tin and lead. Adding it to step e) entails the advantage that the tin and / or lead are easily recovered as part of the first raw
BE2018 / 5875 solder metal composition, and are removed from the process, while the so-called "less noble" metals have a short and direct process route to the second spent slag produced in the downstream step f).
The applicants have determined that step e) is very suitable for the recovery of tin and / or lead, and possibly antimony and / or arsenic, in raw materials or process by-products that are rich in such metals but relatively low in copper and / or nickel. Applicants have found that the first Pb and / or Sn-containing fresh feed may further contain metals which have a higher affinity for oxygen under the conditions of the process than tin and / or lead, such as sodium, potassium, calcium. Such metals can be added, for example, as part of process chemicals used in downstream steps to refine a stream rich in tin and / or lead, such as the first crude solder metal composition or a downstream derivative. Applicants have determined that step e) is very suitable for recovering valuable metals from a scratch by-product formed in one of the refining steps that are carried out as part of the processes disclosed in patent WO 2018/060202 A1 or the like. Such scratch by-product streams usually carry significant amounts of tin and / or lead, but also contain the other metals that may have been added as part of process chemicals.
In one embodiment, the method of the present invention comprises the addition of a fresh feed to the furnace charge of step d). Applicants have determined that step d) is highly suitable for recovering valuable metals from their oxides. The copper, tin and / or lead added as part of fresh feed to step d) in the form of an oxide can be easily recovered as elemental metal in the metal phases formed in step d), e) or f) under the conditions of the process. Applicants have determined that step d) is therefore suitable for, for example, recycling volumes of a final slag that have higher levels of certain metals
BE2018 / 5875 then contains, and is therefore economically or ecologically less suitable for disposal, or volumes of slag layers that have collected as a crust that can grow on the inside of containers used for transporting molten slag from one process step to another. Applicants have found that adding such materials as fresh feed to step d) allows improved recovery of the valuable metals therein.
In an embodiment of the method according to the present invention, the method further comprises the step of:
k) adding at least a portion of the third copper refining slag to the first diluted copper metal composition obtained from step d), thereby forming a second liquid bath, and / or adding at least a portion of the third copper refining slag to step 1) ;
l) partially oxidizing the second liquid bath, thereby forming a first copper metal composition with a high copper metal content and a third solder refining slag, followed by separating the third solder refining slag from the first copper metal composition with a high copper metal content.
Applicants have found that the second enriched copper metal phase formed in step h) can be further enriched in copper by subjecting the stream to the next oxidation step j). The following oxidation step leads to the formation of the third copper refining slag, which may still contain economically significant amounts of valuable metals other than copper, but in which also an economically significant amount of copper is entrained. The advantage is that these valuable non-copper metals become recoverable from the third copper refining slag in a much simpler way compared to the amounts of non-copper metals that would remain in the third enriched copper metal phase if this stream were subjected to a copper electrofining step for the recovery of copper with high purity, in which the non-copper metals often represent a burden on the process. Some non-copper metals remain in it during electro refining
BE2018 / 5875 so-called anode glue, and some other non-copper metals dissolve in the electrolyte.
The applicants have further established that the three consecutive oxidation steps, as part of the series b), h) and j), are capable of extracting from a starting material of black copper which can be freely diluted in copper, but rich in tin and / or lead, to produce a third enriched copper metal phase that has a concentration of copper that is highly suitable for further purification by electro-refining, and can therefore be labeled as “of anode quality”. Applicants have found that the sequence of oxidation steps as indicated is capable of producing, from a black copper with hardly more than 75% by weight copper, a third enriched copper metal phase containing up to 99.0% by weight copper. The applicants have further established that, together with the processing of the black copper supplied to step b), additional copper-containing raw materials can be processed through the indicated sequence of oxidation steps.
Applicants have found that the composition of the third copper refining slag is extremely suitable for being added to the second liquid bath. Applicants therefore prefer to add the complete third copper refining slag into the second liquid bath.
The stream is first of all suitable because the third copper refining slag still contains economically significant amounts of the intended valuable metals tin and / or lead, but is also relatively rich in copper, which can be used as a useful extractant for non-copper metals such as tin and / or lead.
Secondly, the third copper refining slag contains very small amounts of metals that have a higher affinity for oxygen than tin and / or lead under the conditions of the process, more particularly metals that are less desirable in the final purified metal products copper, tin and / or lead, and which are preferably removed from the method of the present invention as part of a spent snail. Because the third copper refining slag is very poor
BE2018 / 5875 to such metals, the addition of this slag in the second liquid bath leads to only very little unnecessary use of useless furnace volume in any of the downstream steps in the process, ie any of the steps in the process process process for such "less noble" metals to end up in a spent slag, such as step 1), in which the second liquid bath is subjected to an oxidation step and leads to a new set of metal phase and slag phase.
The applicants have furthermore found that any further recovery of valuable metals from the second liquid bath, as in step 1), can take place extremely energy-efficient due to the addition of at least a part of the third copper refining slag in step k). In step k), the third copper refining slag added in the second liquid bath upstream of any additional metal recovery steps acts as an oxidizing agent for impurities in the second liquid bath. The copper oxides in the third copper refining slag smoothly reduce to elemental copper in step 1), thereby releasing the oxygen to convert metals that have a higher affinity for oxygen than copper from their elemental metal form to oxides. The elemental copper formed during the processing of the second liquid bath in step l) thereby passes to the metal phase, which in step l) is the first copper metal composition with a high copper metal content. The metals that are converted to their oxides in step 1) pass to the slag phase, i.e. the third solder refining slag. Applicants have found that in step 1) a substantial amount of Sn and / or Pb can be transferred from the metal phase that is supplied to the slag phase. Applicants have also found that these chemical conversions in step 1), from copper oxides to elemental copper and from tin, lead and / or other metals to their oxides, can be triggered with relatively little additional supply of energy, external oxidizing agents and / or reducing agents , and therefore with a relatively limited consumption of energy or process chemicals.
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Applicants have determined that in step 1) most of the copper and nickel present in the first copper metal composition diluted and in the third copper refining slag can be recovered in the first copper metal composition with a high copper metal content, together with an amount of the bismuth and the antimony that may be present, while most of the tin and / or lead in those streams can be recovered in the third solder refining slag. Applicants have found that the third solder refining slag can advantageously become rich in tin and / or lead and also relatively poor in copper, such that this slag can be fairly easily further processed for recovery of the majority of its solder metals in a current flowing on a appears to be raw solder current and is suitable for processing as a raw solder current.
In an embodiment of the method of the present invention, the first copper metal composition with high copper metal content is at least partially recycled to a suitable location upstream in the method. Preferably, that location is step b), but a portion of the recycled stream can be recycled to step h) and / or step j) and / or step c) and / or step d).
Applicants have found that on the one hand the step 1) is also extremely suitable for providing a path for the removal of at least a part of the nickel from the metal casting process as a whole, because there is a high chance that nickel will which upstream location is introduced into the method becomes part of the first copper metal composition with a high copper metal content. On the other hand, the applicants have found that if no nickel, or only a small amount of nickel, is introduced into the process as a whole with the feeds, the first copper metal composition with a high copper metal content has a composition very similar to that of the black copper feed which was provided in step a), and that this first copper metal composition stream with high copper metal content can therefore be easily recycled to step b), or alternatively and / or additionally, partially to any
BE2018 / 5875 which of the following copper oxidation steps h) and j), for recovering the copper from it as part of the third enriched copper metal phase. The method described in U.S. Pat. No. 3,682,623 includes such a recycling of a copper-rich stream to the first oxidation step performed on the black copper. However, any recycling of the first copper metal composition with high copper metal content from step l) to step b), and / or to one of the following steps h) or j) is, in comparison with the prior art, benefited by the upstream removal of impurities in one of the depleted snails, such as the first depleted snail produced in step c) and / or the second depleted snail produced in step f).
Applicants have found that if nickel is present in the feeds to the process, partial recycling of the first copper metal composition with high copper metal content to an upstream location in the process, such as step b), h) or j), has the advantage entails concentrating nickel to a higher content in the first copper metal composition with high copper metal content, compared to a process without such partial recycling. This concentration effect entails the advantage that withdrawing a certain amount of nickel from the process, for example to keep the levels of nickel in certain steps of the process below certain levels, withdrawing a smaller amount of copper together with the amount of nickel required. This entails the advantages that the removal of nickel from the process is more efficient, that the further processing of the extracted copper / nickel mixture can be carried out more efficiently and in smaller equipment, and can also be carried out more efficiently, ie with a lower consumption of energy and / or process chemicals.
Applicants have found that the first copper metal composition with high copper metal content that is withdrawn from the process can be further processed for the recovery of copper and nickel present therein, by means known in the art, or by
BE2018 / 5875 with the means described in our related patent application EP-A-18172598.7.
In one embodiment of the method of the present invention, at the end of step 1), the first copper metal composition with high copper metal content is only partially removed from the furnace, and a portion of this metal composition is held in the furnace together with the third solder refining slag. This portion may represent at least 3 wt%, 4 wt% or 5 wt% of the total first copper metal composition with high copper metal content present in the furnace at the end of step 1), preferably at least 10 wt% , more preferably at least 20 wt%, even more preferably at least 30 wt%, even more preferably at least 40 wt% of the total first copper metal composition with high copper metal content present in the furnace. Applicants have found that this amount of metal improves the usability of the furnace during the current and next process step.
In an embodiment of the method according to the present invention, the method further comprises the following step:
m) partially reducing the third solder refining slag, thereby forming a second diluted copper metal composition and a fourth solder refining slag, followed by separating the fourth solder refining slag from the second diluted copper metal composition.
Applicants have found that the third solder refining slag may contain amounts of copper and / or nickel that are still on the high side for deriving a current of the crude solder type from this slag. Applicants therefore prefer to include the additional partial reduction step m) as part of the method of the present invention. Applicants have found that a significant amount of the copper and / or nickel present in the third solder refining slag can be easily removed as part of the second diluted copper metal composition formed in step m), while most of the tin and / or lead are used as part of the fourth
BE2018 / 5875 soldering refining slag can be retained before further processing is carried out on the fourth soldering refining slag. Preferably, step m) is carried out in such a way that at least 50% by weight of the copper present in step m) is removed as part of the second diluted copper metal composition, more preferably at least 70% by weight, even more preferably at least at least 80% by weight, even more preferably at least 90% by weight. Alternatively, or additionally, step m) is preferably carried out in such a way that at least 50% by weight of the tin present in step m) is recovered in the fourth solder refining slag, more preferably at least 70% by weight, even more preferably at least 80% by weight, even more preferably at least 90% by weight.
In one embodiment of the method of the present invention, at the end of step m), the second diluted copper metal composition is only partially removed from the furnace, and a portion of this metal composition is held in the furnace together with the fourth solder refining slag. This portion may represent at least 1 wt%, 2 wt%, 3 wt%, 4 wt% or 5 wt% of the total second diluted copper metal composition present in the furnace at the end of step m), preferably at least 10% by weight, more preferably at least 20% by weight, even more preferably at least 30% by weight, even more preferably at least 40% by weight of the total second diluted copper metal composition present in the oven. Applicants have found that this amount of metal improves the usability of the furnace during at least one of the following process steps.
In an embodiment of the method according to the present invention, the method further comprises the following step:
n) partially reducing the fourth solder refining slag, thereby forming a second raw solder metal composition and a fifth solder refining slag, followed by separating the second raw solder metal composition from the fifth solder refining slag.
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Applicants have found that the fourth solder refining slag is a highly suitable base material for recovering a raw solder type material, with high acceptability for further processing into high quality purity tin and / or lead products. Applicants have found that in the partial reduction step n) a large portion of the tin and / or lead present in the furnace can be recovered in the second raw solder metal composition, together with virtually all of the copper and / or nickel present, while most of the metals which have a higher affinity for oxygen, such as iron, under the process conditions can be retained as part of the fifth solder refining slag. Applicants have determined that the second raw solder metal composition is suitable for further processing, for example, by subjecting the stream to a silicon metal treatment as described in patent DE 102012005401 A1. Alternatively, or additionally, this second raw solder current, optionally after an enrichment step for increasing the tin and / or lead content, can be further updated as described in WO 2018/060202 A1 or the like, and then subjected to a distillation and recovery of the tin and / or lead as high purity metal products, as described in the same document.
In an embodiment of the method according to the present invention, the method further comprises the following step:
o) partially reducing the fifth solder refining slag, thereby forming a third lead-tin-based metal composition and a third spent slag, followed by separating the third spent slag from the third lead-tin-based metal composition.
Applicants have determined that it is advantageous to provide the additional reduction step o) downstream of the rough soldering production step n), in particular a partial reduction step on the fifth solder refining slag recovered from that step n). Applicants have determined that more valuable metals can become
BE2018 / 5875 extracted from this fifth solder refining slag by step o), which makes the remaining slag even more suitable for use in a valuable end application, and / or for disposal of this slag as spent slag. The applicants have further established that the additional reduction step o) is also able to lower the leachable metals content, such as lead, in the slag to sufficiently low levels for the slag remaining from step o) to be further used as valuable material, or could be disposed of responsibly, with a very limited number of additional treatment steps, and possibly even without further processing steps, for reducing the concentration of sensitive metals such as lead and / or zinc.
In an embodiment of the method according to the present invention, the method further comprises the following step:
p) partially oxidizing the third lead-tin-based metal composition, forming a fourth lead-tin-based metal composition and a sixth solder refining slag, followed by separating the sixth lead-tin-based metal refining slag.
Applicants have found that step p) has the advantage that the third lead-based metal composition recovered from step o) is split into, on the one hand, a metal stream in which the copper from step p) concentrates, along with most of the nickel present and, on the other hand, a slag phase in which very little copper, but a substantial part of the tin and / or lead present in step p), concentrates, together with most of the iron, and if present also zinc. Applicants have found that this division entails the advantage that the two streams resulting from step p) can be processed separately, and preferably also in different ways, using steps that are better suited to their compositions.
In an embodiment of the method according to the present invention, the method further comprises the following step:
BE2018 / 5875
q) recycling at least a portion of the sixth solder refining slag to step d), optionally by adding at least a portion thereof to the first liquid bath before oxidizing the first liquid bath in step d), and / or recycling at least a portion of the sixth solder refining slag to step e), preferably before reducing the first solder refining slag.
Applicants prefer to recycle the sixth solder refining slag to step d) and / or to step e) because this allows a recovery of the tin and / or lead in this slag stream to the first raw solder metal composition from step e) or the second raw solder metal composition from step n), while the iron present in the sixth solder refining slag finds its way fairly easily to the second spent slag from step f) without creating the risk that the iron would accumulate in a cycle forming part of the method according to the present invention.
In an embodiment of the method according to the present invention comprising step p), the method further comprises the following step:
r) recycling at least a portion of the fourth lead-tin-based metal composition to step 1), optionally by adding at least a portion of the fourth lead-tin-based metal composition to the second liquid bath, preferably prior to oxidation of the second liquid bath as part of step 1).
Applicants prefer to recycle the fourth lead-tin-based metal composition to step 1) because this metal stream is highly suitable to be contacted, together with the first diluted copper metal composition from step d), with the third copper refining slag from step j) which is added to the second liquid bath, whereby the third copper refining slag is partially reduced and the two added metal compositions are partially oxidized and a state of equilibrium can arise in which most of the copper present in the furnace, together with the nickel and a
BE2018 / 5875 part of the tin and / or lead, becomes part of the first copper metal composition with a high copper metal content, while any metals (iron, silicon, aluminum) to be rejected, together with a considerable part of the tin and / or lead present , become part of the third solder refining slag produced by step l).
In an embodiment of the method according to the present invention, step o) comprises adding a sixth reducing agent to the step o), i.e. the step of reducing the fifth solder refining slag, preferably before reducing the fifth solder refining slag.
Applicants have found that the sixth reducing agent makes it possible to steer the result of reduction step o) towards the desired separation of valuable metals in the third lead-tin-based metal composition and to leave metals to be rejected in the third used up snail. Applicants have found that the sixth reducing agent can be a gas, such as methane or natural gas, but can also be a solid or a liquid, such as carbon, a hydrocarbon, even aluminum or iron.
In an embodiment of the process of the present invention, and preferably, the sixth reducing agent comprises a metal that has a higher affinity for oxygen under the conditions of the process than tin, lead, copper, and nickel, preferably iron metal, with more preferred scrap iron. Applicants preferably use iron, preferably scrap iron, as the reducing agent, due to their high availability at economically attractive conditions. Applicants have found that the addition of the solid reducing agent may entail the additional advantage that the furnace requires less additional heating to maintain or reach its desired temperature. The applicants have established that this positive effect can be sufficiently large that additional heating, by burning a fuel with the aid of air and / or oxygen, can hardly be required to reach the desired temperature. The applicants have furthermore established that step o) furthermore has a positive effect
BE2018 / 5875 may be affected by the addition of silica, as explained elsewhere in this document.
Applicants prefer to add to step o) an amount of sixth reducing agent that is rich in copper and iron, preferably as a multi-metal material, because such multi-metal material is more readily available at more advantageous conditions than tin of higher purity, copper of higher purity higher purity or iron of higher purity. Another suitable material could be electric motors, preferably such motors after use, because of their high iron content for the cores and copper for the windings. Applicants have found that the copper and / or tin can easily be kept in the metal phase and prevented from passing into the slag phase, while the iron present in this copper-containing fresh feed easily passes to the slag phase as iron oxide while contributing to the chemical reduction of other metals that have a lower affinity for oxygen than iron under the conditions of the process.
In an embodiment of the method according to the present invention, step o) comprises adding a second copper-containing fresh feed to step o), preferably before reducing the fifth solder refining slag.
The applicants have found that the addition of copper in reduction step o) brings a considerable advantage because the copper can act as an excellent extraction agent for any other valuable metals remaining in the fifth solder refining slag remaining after step n), and that this advantageous extraction step can be carried out without loss of significant amounts of copper in the third spent snail produced in step o).
The applicants have further established that the copper-containing fresh feed that can be added in step o) can contain significant amounts of other valuable metals, in particular of zinc, nickel, tin and / or lead. Applicants have
BE2018 / 5875 states that, provided that sufficient copper is provided, the losses of in particular tin and / or lead used up in the third slag consumed can therefore be kept very low and therefore pose no risk to the possible further use or trajectory of this third used up snail, nor an economically significant loss of valuable metals.
Applicants have determined that a wide variety of materials are suitable as a copper-containing fresh feed to step o). However, the applicants prefer that the copper-containing fresh feed to step o) comprises only small amounts, and preferably little to no combustible substances, ie substances that oxidize easily under the conditions of the process, for example organic materials such as plastics and / or or hydrocarbons, residues of fuel or oil, etc., such that the temperature in step o) remains easily controllable.
In an embodiment of the method according to the present invention comprising step o), the second copper-containing fresh feed comprises black copper and / or spent or rejected copper anode material.
Applicants have found that a substantial amount of black copper, the composition of which is similar to that of the black copper provided in step a), can be added in step o) to extract more valuable metals from the fifth solder refining slag obtained from step n) without excessive loss of extra valuable metals in the third spent snail from step o). Applicants have found that the amounts of such black copper from an upstream smelting furnace step acceptable in step o) are very substantial, even on the order of the amount of black copper supplied in step a) as feed for step b). Applicants have found that incorporating step o) in the method of the present invention considerably increases the capacity to process smelting furnace type black copper, and therefore to process larger amounts of lower quality raw materials in which valuable metals in low grade form provided, and consequently
BE2018 / 5875 provide a high potential for upgrading. Applicants have found that this way of performing step o) entails the additional advantage that a substantial portion of the black copper can be processed from the upstream smelting furnace step without having all of that black copper by at least the first step b) of the copper refining sequence has to go. Any metals present in the black copper feed to step o) that have a higher affinity for oxygen than copper under the process conditions are most likely already removed before the copper from this fresh black copper feed to step o) on one or can find its way into step b) and then go through the copper refining process sequence of steps b), h) and j), and end up in the anode quality copper product.
Applicants have also determined that step o) is also extremely suitable for introducing spent and / or rejected copper anode material. The production of high-quality copper generally involves an electrolysis step, in which copper dissolves into the electrolyte from an anode and is deposited again on a cathode. The anode is generally not completely used up and the anode is removed from the electrolysis bath as spent copper anode material before its last copper is dissolved. Applicants have determined that step o) is extremely suitable for introducing such spent copper anode material. Copper anodes for such a copper electrolysis step are typically cast by casting a suitable amount of anode grade molten copper into a mold and allowing the copper to cure after cooling. For copper electrolysis to function properly, the anodes must meet fairly strict dimensions and shape requirements. Anodes that do not comply with this are preferably not used, but form discarded copper anode material. Applicants have determined that step o) is also extremely suitable for introducing such rejected copper anode material.
Applicants prefer to use the spent and / or rejected copper anode material as a solid
BE2018 / 5875, with little to no pre-heating. This entails the advantage that the melting of this material consumes at least a part of the heat of reaction generated by the chemical reactions that take place in step o).
In an embodiment of the method according to the present invention comprising step n), step n) further comprises adding a fifth reducing agent to step n), preferably before reducing the fourth solder refining slag.
Applicants have found that the fifth reducing agent makes it possible to steer the result of reduction step n) in the direction of the desired separation of valuable metals in the second raw solder metal composition and to leave metals to be rejected in the fifth solder refining slag. Applicants have found that the fifth reducing agent can be a gas, such as methane or natural gas, but can also be a solid or a liquid, such as carbon, a hydrocarbon, even aluminum or iron.
In an embodiment of the method of the present invention comprising step n), the fifth reducing agent comprises a metal, and the fifth reducing agent is preferably a metal which, under the conditions of the method, has a higher affinity for oxygen than tin , lead, copper and nickel, the fifth reducing agent preferably comprising iron metal, more preferably scrap iron.
Applicants preferably use iron, preferably scrap iron, as the reducing agent, due to their high availability at economically attractive conditions. Applicants have found that the addition of the solid reducing agents may have the additional positive effect that the furnace requires less additional heating to maintain or reach its desired temperature. Applicants have found that this positive effect may be large enough for additional heating, by burning a fuel with the aid of air and / or oxygen, to remain limited or hardly necessary to achieve the desired temperature.
BE2018 / 5875. The applicants have furthermore determined that step n) may further be positively impacted by the addition of silica, as explained elsewhere in this document.
Preferably, the fifth reducing agent contains little copper and / or nickel, more preferably less than 1% by weight of copper and nickel together. This entails the advantage that little or no additional copper and / or nickel ends up in the second raw solder metal composition, such that any consumption of process chemicals in a downstream step for refining this raw solder composition is not significantly increased.
In an embodiment of the method according to the present invention comprising step n), a second Pb and / or Sn-containing fresh feed is added to step n), preferably before reducing the fourth solder refining slag, the second Pb and / or Sn-containing fresh feed preferably comprises scratch, and is preferably scratch, obtained from downstream processing of concentrated streams of Pb and / or Sn.
Applicants have found that step n) is also a very suitable location in the process for adding materials rich in tin and / or lead, and poor in copper and nickel, but which may contain metals which under the conditions of the process have a higher affinity for oxygen than tin and lead. Adding it to step n) entails the advantage that the tin and / or lead are easily recovered as part of the second raw solder metal composition, and removed from the process, while the so-called "less noble" metals have a short and direct process route to the third spent snail that is produced in the downstream step o).
The applicants have determined that step n) is very suitable for recovering tin and / or lead, and possibly antimony and / or arsenic, in raw materials or process by-products that are rich in such metals but relatively poor in copper and / or nickel. Applicants have determined that the second Pb and / or Sn-containing fresh feed
BE2018 / 5875 may also contain metals which, under the conditions of the process, have a higher affinity for oxygen than tin and / or lead, such as sodium, potassium, calcium. Such metals can be added, for example, as part of process chemicals used in downstream steps to refine a stream rich in tin and / or lead, such as the first or second crude solder metal composition or a downstream derivative thereof. Applicants have determined that step n) is very suitable for recovering valuable metals from a scratch by-product formed in one of the refining steps that are carried out as part of the processes disclosed in patent WO 2018/060202 A1 or the like. Such scratch by-product streams usually carry significant amounts of tin and / or lead, but also contain the other metals that may have been added as part of process chemicals.
In an embodiment of the method according to the present invention comprising step m), the method further comprises the following step:
s) recycling at least a portion of the second diluted copper metal composition formed in step m) to step c), preferably by adding at least a portion of the second diluted copper metal composition before reducing the first copper refining slag as a part of step c), and / or recycling at least a part of the second diluted copper metal composition to step d), preferably before the first lead-tin-based metal composition is oxidized, and / or recycling at least a part of the second diluted copper metal composition to the first liquid bath, preferably before oxidizing the first liquid bath as part of step d).
Applicants have found that, regardless of which recycling option is chosen to recycle the second diluted copper metal composition, the copper recovered in the second diluted copper metal composition, in addition to any nickel present, is easily recovered in the first diluted copper metal composition
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100 copper metal composition which is formed in step d), and further downstream easily finds its way to the first copper metal composition with high copper metal content formed in step 1), with which the copper can be withdrawn from the process, while at the same time any tin and / or present lead in the second diluted copper metal composition easily finds its way to the first solder refining slag which is formed in step d) and can then be recovered further downstream as part of the first raw solder metal composition formed in step e), with which it can then be extracted from the method.
In an embodiment of the method of the present invention comprising step m), step m) further comprises adding a fourth reducing agent to step m), preferably before reducing the third solder refining slag.
Applicants have found that the fourth reducing agent makes it possible to steer the result of reduction step m) in the direction of the desired separation of valuable metals in the second diluted copper metal composition and to leave metals to be discarded in the fourth solder refining slag. Applicants have found that the fourth reducing agent can be a gas, such as methane or natural gas, but can also be a solid or a liquid, such as carbon, a hydrocarbon, even aluminum or iron.
In an embodiment of the method of the present invention comprising step m), the fourth reducing agent comprises a metal, and the fourth reducing agent is preferably a metal which has a higher affinity for oxygen than tin under the conditions of the method , lead, copper and nickel, preferably iron metal, more preferably iron scrap.
Applicants preferably use iron, preferably scrap iron, as the reducing agent, due to their high availability at economically attractive conditions. Applicants have found that the addition of the solid reducing agents may have the additional positive effect that the
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101 oven requires less additional heating to maintain or reach its desired temperature. Applicants have found that this positive effect can be large enough for additional heating by burning a fuel with the aid of air and / or oxygen to remain limited, or even hardly necessary to achieve the desired temperature. The applicants have furthermore established that step m) may furthermore be positively effected by the addition of silica, as explained elsewhere in this document.
Applicants prefer to add to step m) an amount of a fourth reducing agent rich in copper and iron, preferably as a multi-metal material, because such multi-metal material is more readily available at more advantageous conditions than tin of higher purity, copper of higher purity or iron of higher purity. Another suitable material could be electric motors, preferably such motors after use, because of their high iron content for the cores and copper for the windings. Applicants have found that the copper can easily be kept in the metal phase and prevented from moving into the slag phase, while possibly lead, tin and iron in this copper-containing fresh feed smoothly transition to the slag phase as its respective oxide, while the contributes to the chemical reduction of other metals that have a lower affinity for oxygen under the conditions of the process than tin, lead and iron.
In an embodiment of the method according to the present invention, at least one of the process steps involving the separation of a metal phase from a slag phase is added with an amount of silicon dioxide, preferably in the form of sand.
Applicants have found that the silica promotes the formation of the slag phase, improves the fluidity of the slag and improves the gravitational separation of the metal phase from the slag phase. Without wishing to be bound by this theory, the applicants believe that the reduction of the viscosity of the slag in itself brings about a considerable improvement of the phase separation, because the
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102 metal bubbles formed in the slag phase as a result of a chemical reduction, move more easily through the slag phase and thus reach the intermediate phase region between the two phases where they are capable of being combined with the underlying continuous metal phase. The addition of silica also has a positive effect on the balance of certain metals between the metal phase and the slag phase, in particular for lead. The silica also increases the acidity of the slag, which exerts an additional influence on the equilibrium in the oven between the different phases. When the slag contains iron and is removed from the furnace and pelleted by contacting the hot liquid slag with water, the addition of silica may eliminate the risk that the iron is in a form that acts as a catalyst for the splitting of water and therefore the formation of hydrogen gas, which entails an explosion hazard. Silicon dioxide also increases the activity of any tin present in the slag, whereby a portion of the SnO 2 is reduced to Sn metal, whereby this Sn will pass to the metal phase. This latter mechanism lowers the amount of Sn remaining in the slag for the same underlying metal composition.
In an embodiment of the method of the present invention wherein a black copper or a black copper composition is added to at least one of steps b), f) and o), the black copper is produced by a step in a smelting furnace .
Applicants have found that a smelting furnace step is extremely suitable, and even preferred, to produce any, and preferably all, of the black copper compositions used as possible feeds and fresh feeds to process process steps. the present invention, in particular steps b), h), f) and / or o). A smelting furnace step offers the advantage that it is simple in terms of operation and equipment, and therefore economically advantageous. A smelting furnace step brings the additional advantage that it is tolerant in terms of the quality of raw materials. A smelting furnace step is capable of incorporating raw materials that are highly diluted and / or contaminated
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103 are with a wide variety of components, as described above in this document. Because these mixed and / or contaminated raw materials hardly have any other end use, they can be supplied at very attractive economic conditions. The ability to process these raw materials and to upgrade the valuable metals contained therein is therefore of interest to the person carrying out the process of the present invention.
In a smelting furnace, the metals are melted, and organic substances and other combustible materials are removed by incineration. Metals with a relatively high affinity for oxygen are converted to their oxides and collect in the supernatant slag phase with lower density. The metals with a lower affinity for oxygen remain as elemental metal and remain in the bottom of the smelting furnace in the liquid metal phase with higher density. In a copper production step, the smelting step can be carried out in such a way that most of the iron ends up in the slag, while copper, tin and lead end up in the metal product, a stream commonly referred to as "black copper". Most of the nickel, antimony, arsenic and bismuth will also become part of the black copper product.
Applicants have found that the metal product from a smelting furnace step can be introduced into the process of the present invention as a molten liquid, but that it can alternatively be allowed to cure and cool, such as by processing into pellets, which is a possible transport between different industrial sites, and they can subsequently be introduced into the process before or after they have been melted again.
In an embodiment of the method of the present invention, at least one of the first raw solder metal composition and the second raw solder metal composition is pre-refined using silicon metal to produce a pre-refined solder metal composition. A suitable pre-refining treatment for such a crude
BE2018 / 5875
The soldering metal composition is described in the patent DE 102012005401 A1.
In one embodiment, the method of the present invention further comprises the step of cooling the first raw solder metal composition and / or the second raw solder metal composition and / or the pre-refined solder metal composition to a temperature of at most 825 ° C to form a bath that has a contains a first supernatant scratch which floats to the surface through a first liquid molten updated soldering phase. Applicants have found that this additional downstream process step is capable of removing a significant amount of copper and other unwanted metals from the raw solder. Further details about this step can be found in WO 2018/060202 A1 or the like. The applicants have further established that this cooling step, in combination with some of the additional downstream process steps performed on this lead / tin stream, may at least in part be an alternative to the pretreatment with silicon metal mentioned elsewhere in this document. This is advantageous because silicon metal is a fairly scarce process substance, and if its use can be reduced and / or eliminated, that is beneficial.
In one embodiment, the method of the present invention further comprises the step of adding an alkali metal and / or an alkaline earth metal, or a chemical compound comprising an alkali metal and / or an alkaline earth metal, to the first raw solder metal composition and / or to the second raw solder metal composition and / or to the pre-refined solder metal composition and / or to the first liquid molten updated solder phase to form a bath containing a second supernatant scratch, which gravitates to a second liquid molten updated solder phase.
In one embodiment, the method of the present invention further comprises the step of removing the
BE2018 / 5875
105 second supernatant scratch of the second liquid molten updated solder phase, thereby forming a second updated solder.
In one embodiment, the method of the present invention further comprises the step of removing the first superficial scratch from the first liquid molten updated solder phase, thereby forming a first updated solder.
In one embodiment, the method of the present invention further comprises the step of distilling the first updated solder and / or the second updated solder, wherein lead (Pb) is removed from the solder by evaporation and a distillation top product and a distillation bottom product are obtained, preferably by vacuum distillation.
In an embodiment of the method of the present invention comprising the step of distilling at least one of the solder streams for removing lead (Pb) from the solder by evaporation, thereby obtaining a distillation top product and a distillation bottoms product, the distillation bottoms product comprises at least 0.6% by weight of lead. The positive effects thereof are discussed in patent WO 2018/060202 A1.
In an embodiment of the present invention, at least a part of the method is electronically monitored and / or controlled, preferably by a computer program. Applicants have found that electronically controlling steps of the method of the present invention, preferably through a computer program, entails the advantage of much better processing, with results that are much more predictable and that are closer to the objectives of the method. method. For example, the driver can be based on temperature measurements, and if desired also based on measurements of pressures and / or levels, and / or in combination with the results of chemical analyzes of samples taken from process flows and / or analytical results obtained online , control the equipment with regard to the supply or consumption of electrical energy, the supply of heat or a cooling medium, or a
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106 flow and / or pressure control. Applicants have determined that such monitoring or control is particularly advantageous in steps performed in continuous mode, but that it can also be advantageous in steps performed in batch or semi-batch mode. In addition and preferably, the results of monitoring obtained during or after performing steps in the method are also useful for monitoring and / or controlling other steps forming part of the method of the present invention, and / or of methods used upstream or downstream of the method of the present invention, as part of a global process of which the method of the present invention is only a part. Preferably the entire global process is electronically monitored, more preferably by at least one computer program. The global process is preferably controlled electronically as much as possible.
Applicants prefer that the computer control also means that data and instructions are passed from one computer or computer program to at least one other computer or other computer program or other module of the same computer program, for monitoring and / or controlling other methods, including but not limited to the methods described in this document.
Applicants prefer to perform certain steps of the method according to the present invention in a top blown rotary converter or top blown rotary converter (TBRC), optionally an oven as disclosed in U.S. Pat. No. 3,682,623, Figs. 3 5 and the associated description, or an oven of the type generally known as a Kaldo oven or Kaldo converter. Applicants particularly use this type of furnace in the steps in which a chemical reaction takes place and / or in which a balance is desired between a molten slag phase and an underlying molten metal phase.
The applicants have established that this type of furnace allows the processing of complex materials, materials that
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107 produce a large amount of slag phase, and material with large variations in physical appearance and chemical composition. This type of furnace is capable of receiving as slag feed from other process steps and / or large pieces of solid material, i.e. base materials that are much more difficult to introduce into other furnace types.
Such furnaces have the advantage that the furnace can be rotated, such that a more intensive contact between solids and liquids, and between different liquid phases can be obtained, which makes it possible to approach the desired balance between the phases more quickly and / or reach.
Preferably, the rotational speed of the furnace is variable, such that the rotational speed of the furnace can be adapted to the process step performed in the furnace. In process steps where a reaction is required and the furnace content is to be brought to an equilibrium state, a high rotational speed is preferred, while in other process steps, such as when solid fresh feed is to be melted, a low rotational speed may be preferred or possibly not even rotation.
The angle of inclination of the furnace is preferably variable, which allows a better control over the mixing, and therefore also over the reaction kinetics. A variable angle of inclination also allows a better start-up with solid feeds, preferably at a low angle of inclination, until sufficient liquid that is sufficiently hot, and thus more liquid liquid, has been formed to keep the remaining solids floating.
Applicants prefer under certain circumstances not to use the oven at least periodically in the conventional rotary mode, but in a so-called "rocking mode", ie to rotate the oven alternately in opposite directions over only a part of a full 360 ° rotation. The applicants have established that in this operating mode any extreme forces on the oven drive equipment can be avoided that would occur if the oven with the same content
BE2018 / 5875
108 would rotate completely. Applicants prefer to use this mode of operation when there is still a relatively large amount of solids present in the furnace charge, and too little liquid to keep these solids floating, or when the liquid is still little liquid, for example because she is still quite cold.
Applicants prefer that the TBRC is provided with a refractory coating, and more preferably that that coating comprises two layers. Preferably, the inner layer of the coating, ie the layer that comes into contact with the furnace contents, is made of a material that visually becomes lighter at the high temperatures of the furnace contents during full operation, while the underlying layer of material remains dark when it becomes exposed to the internal temperatures of the vessel. This configuration makes it possible to quickly detect defects in the coating by simple visual inspection during the operation of the oven.
The outer layer of the covering thus acts as a kind of safety layer. Applicants prefer that this protective layer has a lower thermal conductivity than the inner coating layer.
When installing the TBRC liner, where the liner is preferably constructed by applying individual, conical refractory blocks, applicants prefer to provide a sacrificial layer between individual liner elements or blocks, such as a cardboard layer or roofing material. This entails the advantage that when the furnace temperature is raised during its first campaign, the sacrificial layer burns up and disappears, and creates space for the thermal expansion of the blocks.
In various steps in the method of the present invention, the underlying molten metal phase is preferably drained from the furnace while the supernatant liquid slag phase is still in the furnace. Applicants prefer to drain this liquid metal through a drain or drain hole
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109 in the refractory oven covering. Applicants prefer to close this hole by means of a sacrificial metal rod during the movements of the oven during operation. To prepare metal tapping, applicants prefer to burn out the rod while keeping it above the liquid level of the furnace, and to temporarily close the burned-out tapping hole with a flammable stopper made, for example, of cardboard , after which the oven is turned to the metal drain position. Applicants have found that the time required to burn the combustible plug provides the time to turn the furnace to the metal drain position and allow the drain hole to pass the slag phase.
To heat the furnace with an external heat source, applicants preferably use a burner that burns a mixture of fuel and an oxygen source, rather than adding the fuel and the oxygen source separately into the furnace. The applicants have found that such a mixing burner may or may be more difficult to use, but the advantage is that the flame can be directed more precisely to the desired location in the oven.
Applicants have found that the ratio of fuel to the oxygen source can be easily used to control furnace oxidation / reduction operation, and thus assist in setting and / or controlling the direction of the chemical reactions that serve to take place in the oven.
Applicants have found that in the steps of the process of the present invention in which cold base materials are introduced, dioxins and / or volatile organic compounds (VOC) can be formed. Applicants prefer to carry out these process steps in furnaces equipped with suitable equipment for collecting dioxins and / or VOCs from the exhaust vapors. Applicants have found that the process can be carried out in such a way that only a part of the ovens must be provided with such exhaust treatment equipment, while for
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110 the other ovens collecting dust and / or filtering is sufficient to meet the legally imposed emission standards.
The method of the present invention provides several occasions to transfer a liquid molten metal / or slag phase from one furnace to another. Applicants have determined that this transfer is the most convenient to carry out using transfer crucibles. To protect the materials from which the transfer crucibles are made, the applicants prefer to provide the ingots with an internal coating of solid slag.
EXAMPLE
The following example demonstrates a preferred embodiment of the present invention. The example is further illustrated by Figure 1, showing a flow chart of the core portion of the method of the present invention. In this part of the process, the following streams are recovered from various different base materials and with a composition of black copper 1 as starting material: a refined copper product of anode quality 9, a copper metal composition with a high copper metal content as a by-product 22, two raw solder metal composition products 18 and 26 , and three spent snails 12, 20 and 28.
Figure 1 shows the figures for the following conclusion elements:
1. Composition of black copper as the basic material for step b) (100)
2. Fresh supply to step b) (100)
3. First copper refining slag
4. First enriched copper metal phase
5. Fresh supply to step h) (200)
6. Second copper refining slag
7. Second enriched copper metal phase
8. Third copper refining slag
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111
9. Third enriched copper metal phase - Anode quality
10. Second metal composition on a lead-tin basis
11. Second diluted copper metal composition
12. First used up snail
13. First metal composition on a lead-tin basis
14. Sixth solder refining slag to the first liquid bath (450) before step d) (500)
15. First diluted copper metal composition
16. First solder refining slag
17. First Pb and / or Sn containing fresh feed to step e) (600)
18. First raw solder metal composition
19. Second solder refining slag
20. Second spent snail
21. Fourth metal composition on a lead-tin basis
22. First copper metal composition with high copper metal content removed from the process
23. Third solder refining slag
24. Fourth solder refining slag
25. Second Pb and / or Sn containing fresh feed to step n) (1000)
26. Second raw solder metal composition
27. Fifth solder refining slag
28. Third spent snail
29. Third metal composition on a lead-tin basis
30. First copper metal composition with high copper metal content recycled to step b) and / or step d)
31. Fresh supply to step j) (300)
50. First copper-containing fresh feed to step f) (700)
51. Fresh supply to step p) (1200)
52. Fresh supply to the second liquid bath (550) before step 1) (800)
53. Sixth solder refining slag recycled to step e) (600)
55. Second fresh copper-containing feed to step o) (1100)
56. Fresh supply to step c) (400)
57. Fresh supply to the first liquid bath (450) before step d) (500)
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112
58. Fresh supply to step m) (900)
450 First liquid bath
550 Second liquid bath
100 Process step b)
200 Process step h)
300 Process step j)
400 Process step c)
500 Process step d)
600 Process step e)
700 Process step f)
701 Process step g)
800 Process step l)
801 Recycling of stream 30 from step l) to process step b) and / or d)
900 Process step m)
901 Process step s), i.e. the recycling of stream 11 from step m) to process step c)
1000 Process step n) 1100 Process step o) 1200 Process step p)
1201 Process step q) - Recycling part of the sixth solder refining slag (14) from step p) to the first liquid bath (450) and / or (53) to process step e) (600)
1202 Process step r) - Recycling the fourth lead-tin-based metal composition (21) from step p) to the second liquid bath (550).
Step b) (100): A top blown rotary converter or top blown rotary converter (TBRC), which is used here as refining furnace for step b) (100), was loaded with 21,345 kg of black copper 1 from an upstream melting furnace, 30,524 kg of a first copper metal composition with high copper metal content 30 recycled from the downstream process step l) (800) as part of a previous process cycle, and 86,060 kg of fresh feed 2. The fresh feed 2 consisted mainly of bronze, red brass and some basic materials rich in copper but poor in other valuable metals. The compositions
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113 and amounts of all feeds to the furnace charge of step b) (100) are shown in Table I. To the feeds charged in this way, an amount of silica flux in the form of sand flux was added that was large enough to produce the desired effects in the plane 5 of phase separation and / or slag fluidity. The feed was melted and / or heated under oxidizing conditions, and partially with oxygen being blown in while the furnace was being rotated.
Table I.
Step b) (100) Black copper1 First Cu-rich metal30 Fresh supply2 tons / load 21,345 30,524 86,060tons % by weight tons % by weight tons % by weight Cu 16,153 75.68% 28,143 92.20% 68,410 79.49% Sn 1,114 5.22% 0.522 1.71% 1,380 1.60% Pb 2,218 10.39% 0.531 1.74% 3,116 3.62% Zn 0.989 4.63% 0.005 0.02% 2,470 2.87% Fe 0.336 1.57% 0.002 0.01% 1,747 2.03% Ni 0.428 2.00% 1,105 3.62% 0.888 1.01% Sb 0.043 0.20% 0.171 0.56% 0.085 0.10% Bi 0.005 0.03% 0.012 0.04% 0.013 0.02% Ash 0.013 0.06% 0.017 0.06% 0.014 0.02%
A substantial amount of the zinc present in the feed was smoked out of the oven. At the end of the first oxidation step b) (100), the first copper refining slag 3 was decanted and transferred to a slag re-treatment furnace to be subjected to process step c) (400). This first copper refining slag 3 was rich in lead, tin, zinc and iron. The detailed composition of this slag 3, as well as the first enriched copper metal phase 4 and dust produced during step b) (100), together with their amounts are shown in
Table II. The first enriched copper metal phase 4 was transferred to another TBRC to be subjected to process step h) (200).
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Table II
Step b) (100) First Curaffin Slag - 3 First enriched copper metal phase - 4 Dust tons / load 27,061116,3711.47 tons % by weight tons % by weight tons % by weight Cu 3,231 11.94% 111,367 95.70% 0.221 15.00% Sn 1,810 6.69% 1,059 0.91% 0.147 10.00% Pb 3,875 14.32% 1,760 1.51% 0.221 15.00% Zn 3,023 11.17% 0.000 0.00% 0.441 30.00% Fe 2,076 7.67% 0.005 0.00% 0.000 0.00% Ni 1.012 3.74% 1,396 1.20% 0.000 0.00% Sb 0.052 0.19% 0.249 0.21% 0.000 0.00% Bi 0.001 0.00% 0.031 0.03% 0.000 0.00% Ash 0.006 0.02% 0.038 0.03% 0.000 0.00%
Step h) (200): To the first enriched copper metal phase 4, 27,091 kg of fresh feed rich in copper 5 was added, as well as an amount of sand flux sufficient to produce the desired effects in terms of phase separation and / or slag fluidity .
This fresh feed consisted of an amount of additional black copper from the upstream smelting furnace, in addition to solid copper-rich material for cooling the furnace temperature. The composition and amounts of the feed to the furnace charge of step h) (200) are shown in Table III.
Table III
Step h) (200) First enriched copper metal phase - 4 Fresh supply5 tons / load 116,371 27,091tons % by weight tons % by weight Cu 111,367 95.70% 23,794 92.48% Sn 1,059 0.91% 0.277 1.08% Pb 1,760 1.51% 0.579 2.25% Zn 0.000 0.00% 0.513 1.99% Fe 0.005 0.00% 0,209 0.81% Ni 1,396 1.20% 0.111 0.51% Sb 0.249 0.21% 0.015 0.06% Bi 0.031 0.03% 0.004 0.01% Ash 0.038 0.03% 0.002 0.01%
Oxidation of the furnace contents was carried out by blowing oxygen into the furnace contents. At the end of the second oxidation step, the second copper refining slag 6 was decanted and transferred to another slag re-treatment furnace to be subjected to step d) (500). The remaining second enriched copper metal phase became 7
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115 transferred to another TBRC to be subjected to step j) (300). The composition and amounts of the second copper refining slag 6 and the second enriched copper metal phase 7 are shown in Table IV. As shown in Table IV, the metal phase 7 was considerably enriched in copper, compared to the furnace feed streams 4 and 5 in Table III.
Table IV
Step h) (200) Second Cu refining slag6 Second enriched copper metal phase - 7 tons / load 17,230 128.573tons % by weight tons % by weight Cu 7,161 41.56% 126.573 98.45% Sn 1,237 7.18% 0.083 0.06% Pb 2.004 11.63% 0.316 0.25% Zn 0.515 2.99% 0.000 0.00% Fe 0.214 1.24% 0.000 0.00% Ni 0.639 3.71% 0.874 0.68% Sb 0.109 0.63% 0.154 0.12% Bi 0.009 0.05% 0.026 0.02% Ash 0.007 0.04% 0.033 0.03%
Step j) (300): To the second enriched copper metal phase 7, a further 22,096 kg of fresh feed rich in copper 31 was added. The composition and amounts of the feeds to the furnace charge of step j) (300) are shown in Table V.
Table V
Step j) (300) Second enriched copper metal phase - 7 Fresh supply31 tons / load 128.573 22,096tons % by weight tons % by weight Cu 126.573 98.45% 20,647 93.44% Sn 0.083 0.06% 0.077 0.35% Pb 0.316 0.25% 0.177 0.80% Zn 0.000 0.00% 0.122 0.87% Fe 0.000 0.00% 0.109 0.49% Ni 0.874 0.68% 0.029 0.13% Sb 0.154 0.12% 0.003 0.02% Bi 0.026 0.02% 0.001 0.00% Ash 0.033 0.03% 0.000 0.00%
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Oxygen blowing was carried out on the furnace contents, and at the end of the blowing period an amount of sand flux was added that was sufficiently large to produce the desired effects in terms of phase separation and / or slag fluidity, before the third copper refining slag 8 was decanted. The remaining copper metal phase of anode grade 9 was removed from the furnace for further processing, e.g. purification by electro refining. The composition and amounts of the third copper refining slag 8 and of the copper of anode quality 9 are indicated in Table VI. As shown in Table VI, the metal phase 9 was further enriched in copper, compared to the furnace feed streams 7 and / or 31 in Table V.
Table VI
Step j)(300) Third Cu refining slag8 Third enriched copper metal phase - 9 Anode quality tons / load 17,024 134,781tons % by weight tons % by weight Cu 12.535 73.63% 133,546 99.08% Sn 0.148 0.81% 0.022 0.02% Pb 0.465 2.73% 0.025 0.02% Zn 0.122 1.13% 0.000 0.00% Fe 0.109 0.64% 0.000 0.00% Ni 0.375 2.20% 0.542 0.40% Sb 0.099 0.58% 0.057 0.04% Bi 0.006 0.04% 0.020 0.02% Ash 0.006 0.03% 0.028 0.02% Step c) (400) : 26,710 kg from the first
copper refining slag 3 (with the composition indicated in Table VII) was introduced into another TBRC used as a slag re-treatment furnace, together with 6,099 kg of fresh feed 56 and 11,229 kg of a second diluted copper metal phase 11 obtained from a process step m) (900) from a previous process cycle, and together with 23,000 kg of a second lead-tin-based metal phase or composition obtained from a process step f) (700) of a previous process cycle. 10,127 kg of scrap iron was added to this furnace content as a reducing agent. Furthermore, an amount of sand flux was added that was sufficiently large to produce the desired effects
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117 in the field of safety, phase separation and / or slag fluidity. Once the filling was complete, the oven was rotated at a speed in the range of 18-20 rpm. The composition and amounts of the feed to the furnace charge of step c) (400) are shown in Table VII.
Table VII
Step c)(400) First Curaffin Slag -3 Fresh supply56 Second dilutedCu metal phase - 11 Second Metal Phase on PbSn basis - 10 tons / load 26,710 6,099 11,229 23,000tons % by weight tons % by weight tons % by weight tons % by weight Cu 3,189 11.94% 0.987 16.18% 6,960 61.98% 16,665 72.50% Sn 1,787 6.69% 0.325 5.32% 2,095 18.66% 1,685 7.33% Pb 3,825 14.32% 0.419 6.87% 0.775 6.90% 2,521 10.97% Zn 2,983 11.17% 0.178 2.92% 0.006 0.05% 0.381 1.66% Fe 2,049 7.67% 1,440 23.61% 0.020 0.18% 1,233 5.36% Ni 0.999 3.74% 0.135 2.21% 1,291 11.50% 0.429 1.87% Sb 0.052 0.19% 0.017 0.28% 0.073 0.65% 0.044 0.19% Bi 0.001 0.00% 0.000 0.00% 0.002 0.02% 0.006 0.02% Ash 0.006 0.02% 0.000 0.00% 0.003 0.03% 0.011 0.05% When the reduction made of copper and tin and lead
Sufficiently advanced, a first lead-based metal composition 13, dust and a first spent slag 12 were produced. The compositions and quantities of these products are indicated in Table VIII. The first spent snail 12 was decanted and removed from the process. The first lead-tin-based metal composition 13 was transferred to another TBRC to become part of the first liquid bath 450.
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Table VIII
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Step c)(400) First used up snail12 First metal phase onPb-Sn basis - 13 Dust tons / load 31,287 46.718 1,346tons % by weight tons % by weight tons % by weight Cu 0.111 0.35% 28,105 60.32% 0.031 2.27% Sn 0.074 0.24% 5,645 12.11% 0.170 12.64% Pb 0.166 0.50% 7,176 15.40% 0.296 20.52% Zn 2,372 7.58% 0.568 1.22% 0.612 45.50% Fe 12,049 38.51% 2,047 4.39% 0.010 0.71% Ni 0.012 0.04% 2,834 6.08% 0.002 0.12% Sb 0.000 0.00% 0.164 0.39% 0.002 0.18% Bi 0.000 0.00% 0.008 0.02% 0.000 0.00% Ash 0.000 0.00% 0.016 0.03% 0.004 0.31%
Step d) (500): To form the first liquid bath 450, to the 46,718 kg of the first lead-based metal composition 13 17,164 kg of the second copper refining slag 6 (with the composition indicated in Table IV) was added together with 9,541 kg of fresh feed 57, and 474 kg of sixth solder refining slag 14 (recycled from the downstream process step p) (1200) as part of a previous process cycle). Furthermore, an amount of sand flux was added that was large enough to produce the desired effects on the plane of phase separation and / or slag fluidity. The compositions and amounts of the components of the first liquid bath 450 that formed the furnace charge for step d) (500) are shown in Table IX.
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Table IX
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Step d)(500) First metal phase on a Pb-Sn basis 13 Fresh supply57 Sixth solderrefining slag - 14 Second Curaffin Slag - 6 tons / load 46.718 9,541 0.474 17,164tons % by weight tons % by weight tons % by weight tons % by weight Cu 28,105 60.32% 1,749 22.09% 0.015 3.08% 7.133 41.56% Sn 5,645 12.11% 0.484 6.11% 0.021 4.51% 1,232 7.18% Pb 7,176 15.40% 0.677 8.54% 0.060 12.69% 1,996 11.63% Zn 0.568 1.22% 0.308 3.89% 0.025 5.30% 0.513 2.99% Fe 2,047 4.39% 2,675 33.77% 0.134 28.21% 0.213 1.24% Ni 2,834 6.08% 0,209 2.63% 0.002 0.33% 0.637 3.71% Sb 0.164 0.39% 0.028 0.35% 0.000 0.01% 0.08 0.63% Bi 0.008 0.02% 0.000 0.00% 0.000 0.00% 0.009 0.05% Ash 0.016 0.03% 0.000 0.00% 0.000 0.00% 0.007 0.04%
The mixture of slag and metal phase was reacted until the concentrations of copper and / or nickel were sufficiently reduced in the slag phase. The reaction caused more tin and lead to enter the slag phase. At that point, the oven was drained at the bottom, whereby a first diluted copper metal composition was removed from the oven. The first solder refining slag 16, along with about 1 ton remaining from the first diluted copper metal phase 15, was taken to another TBRC to be subjected to the next step e) (600). The compositions and amounts of both product streams obtained from step 500, with the exception of the 1 tonne metal phase remaining with the slag phase, are shown in Table X.
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Table X.
Step d) (500) First Solder Refining Snail - 16 First diluted Cumetal phase - 15 tons / load 28,200 49,792tons % by weight tons % by weight Cu 1.047 3.71% 35,387 71.07% Sn 1,375 4.87% 5.925 11.90% Pb 5,268 18.68% 4,541 9.12% Zn 1,393 4.94% 0.023 0.05% Fe 5,059 17.94% 0.013 0.03% Ni 0.282 1.00% 3,331 6.69% Sb 0.010 0.04% 0.304 0.61% Bi 0.000 0.00% 0.017 0.03% Ash 0.000 0.00% 0.022 0.05%
The first diluted Cu metal phase from step d) contained about 0.08% by weight of silver (Ag) and 0.03% by weight of sulfur.
Step e) (600): 14,987 kg of the first lead and tin-containing fresh feed 17 was fed to the first solder refining slag 16 before this mixture was reduced in step e) (600). The reduction was carried out by adding 8,017 kg of scrap iron as a reducing agent. Further, as part of step e) (600), 8,650 kg of the sixth solder refining slag 53 obtained from the downstream process step p) (1200) was added to the furnace as part of a previous process cycle, as well as an amount of sand flux sufficient to to produce the desired effects in terms of phase separation and / or slag fluidity. The compositions and amounts of the feeds that formed the furnace charge for step e) (600) are shown in Table XI.
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Table XI
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Step e)(600) First solder refining slag -16 1st Pb and / or Sn containing fresh feed - 17 Sixth solder refining slag - 53 First diluted Cu metal phase 15 tons / load 28,200 14.987 8,650 1,000tons % by weight tons % by weight tons % by weight tons % by weight Cu 1.047 3.71% 1,361 9.08% 0.266 3.08% 0.711 71.07% Sn 1,375 4.87% 4,184 27.92% 0.390 4.51% 0.119 11.90% Pb 5,268 18.68% 7,738 51.63% 1.098 12.69% 0.091 9.12% Zn 1,393 4.94% 0.043 0.29% 0.458 5.30% 0.000 0.05% Fe 5,059 17.94% 0.106 0.71% 2,440 28.21% 0.000 0.03% Ni 0.282 1.00% 0.011 0.07% 0.029 0.33% 0.067 6.69% Sb 0.010 0.04% 0.298 1.99% 0.001 0.01% 0.006 0.61% Bi 0.000 0.00% 0.002 0.01% 0.000 0.00% 0.000 0.03% Ash 0.000 0.00% 0.000 0.00% 0.000 0.00% 0.000 0.05%
A significant amount of zinc was smoked from the furnace contents during this partial reduction step. The reduction was stopped when the concentration of Sn in the slag phase 5 had reached approximately the target level. At that point, the furnace was again drained at the bottom to remove the first raw solder metal composition 18 from the process. The first raw solder metal composition 18 was further processed into high-quality lead and tin products. The second solder refining slag 19 was fed to another TBRC for further processing as part of step f) (700). The compositions and amounts of the first raw solder metal 18, the second solder refining slag 19 and the dust obtained from step e) (600) are shown in Table XII.
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Table XII
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Step e)(600) First raw solder metal composition - 18 Second Solder Refining Snail - 19 Dust tons / load 23,132 36,667 1,551tons % by weight tons % by weight tons % by weight Cu 3,256 13.53% 0.166 0.39% 0.016 1.06% Sn 5,389 22.40% 0.778 2.60% 0.150 9.64% Pb 13.224 54.97% 0.652 2.18% 0.318 20.52% Zn 0.087 0.36% 1,106 3.70% 0.706 45.50% Fe 0.282 1.17% 15.003 50.20% 0.011 0.71% Ni 0.354 1.47% 0.032 0.11% 0.002 0.12% Sb 0.311 1.29% 0.002 0.01% 0.003 0.18% Bi 0.002 0.01% 0.000 0.00% 0.000 0.00% Ash 0.000 0.00% 0.000 0.00% 0.000 0.03%
Step f) (700): A further reduction step was performed on the second solder refining slag 19 by adding 1,207 kg of scrap iron as a reducing agent. Furthermore, as part 5 of step f) (700), 22,234 kg was added of a first fresh feed rich in copper 50, and an amount of sand flux sufficient to produce the desired effects in terms of safety, phase separation and / or snail fluidity. This fresh feed 50 consisted of an amount of additional black copper from the upstream smelting furnace, as well as an amount of slag materials that were collected as a remnant of other process steps. The compositions and amounts of the feeds to the furnace charge of step f) (700) are indicated in Table XIII.
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Table XIII
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Step f) (700) Second Solder Refining Snail - 19 Cu-containing fresh feed - 50 tons / load 36,667 22,234tons % by weight tons % by weight Cu 0.166 0.39% 16,630 75.95% Sn 0.778 2.60% 1.003 4.58% Pb 0.652 2.18% 2,052 9.37% Zn 1,106 3.70% 1.010 4.61% Fe 15.003 50.20% 0.509 2.32% Ni 0.032 0.11% 0.405 1.85% Sb 0.002 0.01% 0.042 0.19% Bi 0.000 0.00% 0.005 0.03% Ash 0.000 0.00% 0.011 0.05%
When Cu, Sn, and Pb in the slag were reduced to a maximum of 0.50% each, a second lead-tin-based metal phase 10 and a second spent slag were produced. The compositions and amounts thereof are indicated in Table XIV. The second spent slag was decanted and removed from the process. The second lead-tin-based metal composition 10 was passed to step c) (400) of the following process cycle, before the first copper refining slag (3) was reduced.
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Table XIV
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Step f) (700) Second Metal Phase on Pb-Sn basis - 10 Second spent snail 20 tons / load 23,000 37.523tons % by weight tons % by weight Cu 16,665 72.50% 0.115 0.31% Sn 1,685 7.33% 0.090 0.24% Pb 2,521 10.97% 0.188 0.50% Zn 0.381 1.66% 1,726 4.60% Fe 1,233 5.36% 15,384 41.00% Ni 0.429 1.87% 0.010 0.03% Sb 0.044 0.19% 0.000 0.00% Bi 0.006 0.02% 0.000 0.00% Ash 0.011 0.05% 0.000 0.00%
Step 1) (800): 17,024 kg of the third copper refining slag 8 (with the composition shown in Table VI) was fed to a TBRC which was used as a slag re-treatment furnace, together with 14,920 kg of fresh feed rich in copper 52 and 49,792 kg of the first diluted copper metal phase 15 obtained from step d) (500). Furthermore, an amount of sand flux was added that was sufficiently large to produce the desired effects in terms of phase separation and / or slag fluidity. These materials were melted together with the fourth metal-phase lead-tin based 21 (20,665 kg) obtained from the downstream process step p) (1200) as part of a previous process cycle. Together, these feeds formed the second liquid bath 550. Once the filling and melting was completed, the oven was rotated at a speed of 20 rpm. The compositions and amounts of the feeds to the slag re-treatment furnace charge for step 1) (800) are shown in Table XV.
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Table XV
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Step l)(800) FourthMetal phase onPb-Sn basis - 21 Fresh supply52 First dilutedCu metal phase - 15 Third Curefining slag - 8 tons / load 20,665 14.920 49,792 17,024tons % by weight tons % by weight tons % by weight tons % by weight Cu 16,483 79.76% 3,985 30.10% 35,387 71.07% 12.535 73.63% Sn 1,882 9.11% 0.610 4.61% 5.925 11.90% 0.148 0.81% Pb 1,643 7.95% 3,104 23.45% 4,541 9.12% 0.465 2.73% Zn 0.019 0.09% 0.792 5.98% 0.023 0.05% 0.122 1.13% Fe 0.012 0.06% 1,363 10.29% 0.013 0.03% 0.109 0.64% Ni 0.533 2.58% 0.316 2.39% 3,331 6.69% 0.375 2.20% Sb 0.063 0.31% 0.043 0.33% 0.304 0.61% 0.099 0.58% Bi 0.006 0.03% 0.000 0.00% 0.017 0.03% 0.006 0.04% Ash 0.011 0.05% 0.000 0.00% 0.022 0.05% 0.006 0.03%
The mixture was reacted, if necessary also partially oxidized by blowing oxygen, until the concentrations of copper and nickel in the slag reached approximately their target values. At that point, the furnace was drained at the bottom to remove 64,500 kg of the first copper metal composition with high copper metal content (streams 22 and 30 together) from the third solder refining slag 23. The third solder refining slag 23, together with about 6 tons of the first copper metal phase with a high copper metal content that had remained with the slag, was transferred to another TBRC for further processing as part of step m) (900). The compositions and amounts of the product streams at the end of step 1) (800) are shown in Table XVI, and this time including the 6 ton metal phase remaining with the slag phase on the way to the next treatment step.
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Table XVI
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Step l)(800) First Cu metal phase with high content of Cumetal 22 + 30 Third solder refining slag23 tons / load 70,500 39.276tons % by weight tons % by weight Cu 59,469 92.20% 3,182 8.10% Sn 1,103 1.71% 7,317 18.63% Pb 1,122 1.74% 8,515 21.68% Zn 0.011 0.02% 1.013 2.58% Fe 0.004 0.01% 1,496 3.81% Ni 2,335 3.62% 1,980 5.04% Sb 0.362 0.56% 0.114 0.29% Bi 0.026 0.04% 0.000 0.00% Ash 0.036 0.06% 0.000 0.00%
30,524 kg of the first copper metal composition with high copper metal content in the furnace was fed into the copper refining furnace as stream 30, before a new step b) (100) of a following cycle was started. A further 33,976 kg was removed from the process as stream 22, for further processing.
Step m) (900): After removing the (30,524 kg + 33,976 kg =) 64,500 kg of the first copper metal phase with high copper metal content (22 + 30) from the furnace, the furnace content was passed to another TBRC for further processing as part of step m) (900). The mixture of the 39,276 kg of third solder refining slag 23 and the 6 tons of metal with the composition of the first copper metal composition with high copper metal content was partially reduced as part of step m) (900). Scrap iron was added as a reducing agent. Furthermore, an amount of sand flux was added to step m) that was sufficiently large to produce the desired effects in terms of phase separation and / or slag fluidity, and a small amount (37 kg) of fresh feed 58. The compositions and amounts of the feed which constituted the furnace charge for step m) (900) are indicated in Table XVII.
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Table XVII
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Step m) (900) Third solder refining slag - 23 Fresh supply58 Metal phase that remained with the slag (23) tons / load 39.276 0.037 6,000 0tons % by weight tons % by weight tons % by weight Cu 3,182 8.10% 0.001 2.38% 5,532 92.20% Sn 7,317 18.63% 0.001 3.31% 0.103 1.71% Pb 8,515 21.68% 0.004 10.88% 0.104 1.74% Zn 1.013 2.58% 0.002 5.94% 0.001 0.02% Fe 1,496 3.81% 0.010 27.53% 0.000 0.01% Ni 1,980 5.04% 0.000 0.22% 0.217 3.62% Sb 0.114 0.29% 0.000 0.00% 0.034 0.56% Bi 0.000 0.00% 0.000 0.00% 0.002 0.04% Ash 0.000 0.00% 0.000 0.00% 0.003 0.06%
The reduction step m) (900) was stopped when the copper and nickel concentrations in the slag phase were sufficiently reduced. At that point, the furnace was drained at the bottom to remove an amount of 11,229 kg of second diluted copper metal composition 11 for further processing in step c) (400) of a subsequent process cycle. A fourth solder refining slag 24, together with approximately 1,400 kg of metal with the composition of the second diluted copper metal phase 11, was fed to another TBRC to be subjected to step n) (1000). The compositions and total amounts of the second diluted copper metal phase or composition 11 and of the fourth solder refining slag 24 are shown in Table XVIII, wherein the 1,400 kg of metal phase remaining with the slag phase is included in the total stated amount for the second diluted copper metal phase 11.
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Table XVIII
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Step m) (900) Second diluted Cumetal phase - 11 Fourth solder refining slag - 24 tons / load 12.629 41,342tons % by weight tons % by weight Cu 6,960 61.98% 1,389 3.36% Sn 2,095 18.66% 5,069 12.26% Pb 0.775 6.90% 7,743 18.73% Zn 0.006 0.05% 1.009 2.44% Fe 0.020 0.18% 9,037 21.86% Ni 1,291 11.50% 0.752 1.82% Sb 0.073 0.65% 0.066 0.16% Bi 0.002 0.02% 0.000 0.00% Ash 0.003 0.03% 0.000 0.00%
The second diluted Cu metal phase 11 from step m) contained about 0.11% by weight of silver (Ag) and 0.01% by weight of sulfur.
Step n) (1000): After the 11,229 kg of the second diluted copper metal phase 11 was drained from the furnace, the remaining furnace content was transferred to another TBRC to perform step n) (1000). 11,789 kg of second lead and tin-containing fresh feed 25 was added as part of step n) (1000) and the furnace content was further reduced. The reduction was carried out by adding 9,692 kg of scrap iron as a reducing agent, together with an amount of sand flux that was large enough to produce the desired effects in terms of phase separation and / or slag fluidity. The compositions and amounts of the various furnace feeds for step n) (1000) are shown in Table XIX.
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Table XIX
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Step n) (1000) Fourth solder refining slag - 24 Fresh supply25 Second diluted Cu metal phase - 11 tons / load 41,342 11,789 1,400tons % by weight tons % by weight tons % by weight Cu 1,389 3.36% 0.728 6.18% 0.888 61.98% Sn 5,069 12.26% 1,864 15.81% 0.261 18.66% Pb 7,743 18.73% 8,790 74.56% 0.097 6.90% Zn 1.009 2.44% 0.019 0.16% 0.001 0.05% Fe 9,037 21.86% 0.070 0.59% 0.003 0.18% Ni 0.752 1.82% 0.003 0.02% 0.161 11.50% Sb 0.066 0.16% 0.074 0.63% 0.009 0.65% Bi 0.000 0.00% 0.037 0.32% 0.000 0.02% Ash 0.000 0.00% 0.000 0.00% 0.000 0.03%
The partial reduction step was stopped when the concentration of tin in the slag phase had reached approximately the target level. At that point, the furnace was again drained from the bottom to remove the second raw solder metal composition 26 from the furnace, leaving only the fifth solder refining slag 27 in the furnace. The second raw solder metal composition 26 was further processed into high-quality lead and tin products. The fifth solder refining slag 27 was transferred to another TBRC to perform step o) (1100).
The compositions and amounts of the second raw solder metal 26 and of the fifth solder refining slag 27 are shown in Table XX.
Table XX
Step n) (1000) Second Raw Solder 26 Fifth solder refining slag27 tons / load 23,080 41,956tons % by weight tons % by weight Cu 2,934 10.57% 0.054 0.13% Sn 6.245 22.49% 0.975 2.32% Pb 16,080 57.90% 0.550 1.31% Zn 0.000 0.00% 1.032 2.46% Fe 1,363 4.91% 17,373 41.41% Ni 0.895 3.22% 0.021 0.05% Sb 0.149 0.54% 0.000 0.00% Bi 0.038 0.14% 0.000 0.00% Ash 0.000 0.00% 0.000 0.00%
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Step o) (1100): A further reduction step was performed on the fifth solder refining slag 27 by adding 922 kg of scrap iron as a reducing agent, together with 23,735 kg of fresh feed rich in copper 55 and an amount of sand flux that was large enough to to produce desired effects in terms of safety, phase separation and / or slag fluidity. The second copper-containing fresh feed 55 essentially consisted of additional black copper from the upstream smelting furnace. The compositions and amounts of the feeds to step o) (1100) are indicated in Table XXI.
Table XXI
Step o) (1100) Fifth solder refining slag27 Cu-containing fresh feed 55 tons / load 41,956 23,735tons % by weight tons % by weight Cu 0.054 0.13% 15,456 67.27% Sn 0.975 2.32% 0.997 4.34% Pb 0.550 1.31% 2,022 8.80% Zn 1.032 2.46% 1,097 4.77% Fe 17,373 41.41% 1,603 6.98% Ni 0.021 0.05% 0.391 1.70% Sb 0.000 0.00% 0.040 0.17% Bi 0.000 0.00% 0.005 0.02% Ash 0.000 0.00% 0.011 0.05%
The reduction was continued until an acceptable quality of spent snail was obtained. When this goal was achieved, a third metal-phase based on lead-tin 29 and a third spent slag were produced, the compositions and amounts of which are given in Table XXII. The third spent snail 28 was decanted and removed from the process. The third metal composition on lead-tin base 29 was transferred to the TBRC intended for performing step p) (1200).
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Table XXII
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Step o) (1100) Third Metal Phase on Pb-Snbase - 29 Third used up snail28 tons / load 22,300 45,542tons % by weight tons % by weight Cu 15,446 69.56% 0.155 0.34% Sn 1,923 8.66% 0.069 0.15% Pb 2,417 10.88% 0.205 0.45% Zn 0.347 1.56% 1,812 3.98% Fe 1,598 7.20% 18,522 40.67% Ni 0.406 1.83% 0.015 0.03% Sb 0.041 0.18% 0.000 0.00% Bi 0.005 0.02% 0.000 0.00% Ash 0.011 0.05% 0.000 0.00%
Step p) (1200): To the third metal composition on lead-tin base 29 was added 5,204 kg of fresh feed 51, together with an amount of sand flux sufficient to produce the desired effects in terms of phase separation and / or slag fluidity. Subsequently, by partial oxidation, the majority of the iron and zinc were oxidized from the metal phase and to the slag phase. The compositions and amounts of the products from this oxidation step p) (1200) are shown in Table XXIII.
Table XXIII
Step p) (1200) Third Metal Phase on Pb-Snbase - 29 Fresh supply51 tons / load 22,300 5,204tons % by weight tons % by weight Cu 15,446 69.56% 1,402 32.04% Sn 1,923 8.66% 0.368 8.42% Pb 2,417 10.88% 0.386 8.83% Zn 0.347 1.56% 0.166 3.56% Fe 1,598 7.20% 0.989 22.61% Ni 0.406 1.83% 0.158 3.61% Sb 0.041 0.18% 0.023 0.54% Bi 0.005 0.02% 0.000 0.01% Ash 0.011 0.05% 0.000 0.00%
When the oxidation of iron and zinc was sufficiently advanced, a fourth lead-tin-based metal composition 21 and a sixth solder refining slag 14 were produced, the
BE2018 / 5875
132 compositions and amounts are indicated in Table XXIV. The sixth solder refining slag 14 was decanted and was added at least partially as stream 14 to the first liquid bath (450), and / or at least partially as stream 53 added to step e) (600) of the following process cycle. The fourth lead-tin-based metal composition 21 was transferred to another TBRC to become part of the second liquid bath 550 and to perform step 1) (800) as part of the following process cycle.
Table XXIV
Step p) (1200) Fourth Metal phase on Pb-Sn basis - 21 Sixth solder refining slag14 tons / load 20,665 9.124tons % by weight tons % by weight Cu 16,483 79.76% 0.281 3.08% Sn 1,882 9.11% 0.411 4.51% Pb 1,643 7.95% 1,158 12.69% Zn 0.019 0.09% 0.483 5.30% Fe 0.012 0.06% 2,573 28.21% Ni 0.533 2.58% 0.030 0.33% Sb 0.063 0.31% 0.001 0.01% Bi 0.006 0.03% 0.000 0.00% Ash 0.011 0.05% 0.000 0.00%
The process steps 100-1200 involving molten metal and / or slag phases are all carried out at a temperature in the range of 1100 to 1250 ° C. Depending on the purpose of the step, its operating temperature may preferably be close to the upper or lower end of this temperature range.
Applicants have determined that the embodiment of the method described in this Example can be performed in a limited number of TBRCs. Applicants have succeeded in carrying out this method in only 8 ovens, several of which are preferably of the TBRC type. Applicants prefer to perform this method in only 6 ovens, more preferably in only 5 ovens, even more preferably in only 4 ovens, even more preferably in only 3 ovens.
BE2018 / 5875
133
Now that this invention has been fully described, it will be clear to those skilled in the art that the invention can be implemented with a wide range of parameters within what is claimed, without thereby falling outside the scope of the invention as defined by the claims.

权利要求:
Claims (53)
[1]
CONCLUSIONS
1. Diluted copper metal composition (11,
15) which, by weight and in proportion to its total dry weight, comprises:
· At least 57% by weight and at most 85% by weight of copper, · at least 3.0% by weight of nickel, · at most 0.8% by weight of iron · at least 7% by weight and at most 25% by weight. % tin, and · at least 3% by weight and at most 15% by weight of lead.
[2]
The diluted copper metal composition according to claim 1, which comprises at most 0.60% by weight of iron.
[3]
The diluted copper metal composition according to claims 1 or 2, which comprises at most 3.0% by weight of zinc.
[4]
The diluted copper metal composition according to any of the preceding claims, which is at most
1.5 wt% antimony.
[5]
The diluted copper metal composition according to any of the preceding claims, comprising at least 4.0% by weight of nickel.
[6]
The diluted copper metal composition according to any of the preceding claims, comprising at most 15% nickel by weight.
[7]
The diluted copper metal composition according to any of the preceding claims, comprising at most 0.30% by weight of silver.
[8]
The diluted copper metal composition according to any of the preceding claims, comprising at most 0.1 wt% bismuth.
[9]
The diluted copper metal composition according to any of the preceding claims, comprising at most 0.15% arsenic by weight.
[10]
The diluted copper metal composition according to any of the preceding claims, which is at most
BE2018 / 5875
135
1.0 wt% sulfur.
[11]
A method for preparing a first diluted copper metal composition (15) according to any of claims 1 to 10, the method comprising the steps of:
a) providing a composition of black copper (1) comprising at least 50% by weight of copper and at least 1.0% by weight of tin, together with at least 1.0% by weight of lead,
b) partially oxidizing (100) the black copper composition (1), thereby forming a first enriched copper metal phase (4) and a first copper refining slag (3), followed by separating the first copper refining slag (3) from the first enriched copper metal phase (4),
h) partially oxidizing (200) the first enriched copper metal phase (4), thereby forming a second enriched copper metal phase (7) and a second copper refining slag (6), followed by separating the second copper refining slag (6) from the second enriched copper copper metal phase (7), wherein at least 37.0% by weight of the total amount of the tin and lead processed through process steps b) (100) and / or h) (200) is recovered in the first copper refining slag (3) ) and the second copper refining slag (6) together,
j) partially oxidizing (300) the second enriched copper metal phase (7), thereby forming a third enriched copper metal phase (9) and a third copper refining slag (8), followed by separating the third copper refining slag (8) from the third enriched copper copper metal phase (9),
i) adding at least a portion of the second copper refining slag (6) or of the third copper refining slag (8) to a metal composition (13) containing copper together with at least one soldering metal selected from tin and lead, whereby a first liquid bath (450) is formed, and
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136
d) partially oxidizing (500) the first liquid bath (450), thereby forming the first diluted copper metal composition (15) according to any of claims 1 to 10 and a first solder refining slag (16), followed by separating the first solder refining slag (16) from the first diluted copper metal composition (15).
[12]
The method of claim 11, further comprising the step of
c) partially reducing (400) the first copper refining slag (3), thereby forming a first lead-tin metal composition (13) and a first spent slag (12), followed by separating the first spent slag (12) from the first lead-tin-based metal composition (13), and adding the first lead-tin-based metal composition (13) to the first liquid bath (450) as the metal composition of step i) containing copper together with at least one soldering metal that is selected from tin and lead.
[13]
The method of claim 12, wherein step c) comprises adding a first reducing agent (R1) to step c).
[14]
The method of claim 13, wherein the first reducing agent (R1) comprises a metal that has a higher affinity for oxygen under the conditions of the method than tin, lead, copper, and nickel, preferably iron metal, more preferably scrap iron.
[15]
The method according to any of claims 11-14 wherein in step i) at least a portion of the second copper refining slag (6) is added to the first liquid bath (450) and / or to step d).
[16]
The method according to any of claims 11-15 wherein the black copper composition (1) meets at least one of the following conditions:
· Comprising at least 51% by weight of copper, · including at most 96.9% by weight of copper,
BE2018 / 5875
137 · comprising at least 0.1% by weight of nickel, · comprising at most 4.0% by weight of nickel, · covering at least 1.5% by weight of tin, · covering at most 15% % by weight of tin, · comprising at least 1.5% by weight of lead, • including at most 25% by weight of lead, • including at most 3.5% by weight of iron, and • including a maximum of 8.0% by weight of zinc.
[17]
The method according to any of claims 11 or 16, further comprising the following step:
e) partially reducing (600) the first solder refining slag (16), thereby forming a first rough solder metal composition (18) and a second solder refining slag (19), followed by separating the second solder refining slag (19) from the first raw solder metal composition (19) (18).
[18]
The method of claim 17, further comprising the following step:
f) partially reducing (700) the second solder refining slag (19), thereby forming a second lead-tin-based metal composition (10) and a second spent slag (20), followed by separating the second spent slag (20) of the second metal composition on a lead-tin basis (10).
[19]
The method of claim 18, further comprising adding a first copper-containing material (50) to step f) (700).
[20]
The method of claim 19, wherein the first copper-containing material (50) comprises black copper and / or spent or rejected copper anode material.
[21]
The method of any one of claims 18-20, wherein step f) (700) comprises adding a third reducing agent (R3) to step f) (700).
BE2018 / 5875
138
[22]
The method of claim 21, wherein the third reducing agent (R3) comprises a metal that has a higher affinity for oxygen under the conditions of the method than tin and lead, preferably iron metal, more preferably scrap iron.
[23]
The method of any one of claims 18 to 22, further comprising the following step:
g) recycling (701) at least a portion of the second lead-tin-based metal composition (10) to step c) (400).
[24]
The method of any one of claims 17 to 23, wherein step e) (600) comprises adding a second reducing agent (R2) to step e) (600).
[25]
The method of claim 24, wherein the second reducing agent (R2) comprises a metal that has a higher affinity for oxygen under the conditions of the method than tin, lead, copper, and nickel, wherein the second reducing agent (R2) at preferably iron metal, more preferably scrap iron.
[26]
The method of any one of claims 17 to 25, wherein a first Pb and / or Sn containing material (17) is added to step e) (600), wherein the first containing Pb and / or Sn material (17) preferably comprises scratch, and is preferably scratch, obtained from downstream processing of concentrated streams of Pb and / or Sn.
[27]
The method of any one of claims 11 to 26, further comprising the following steps:
k) adding at least a portion of the third copper refining slag (8) to the first diluted copper metal composition (15) obtained from step d) (500), thereby forming a second liquid bath (550), and / or the adding at least a portion of the third copper refining slag (8) to step 1) (800);
l) partially oxidizing (800) the second liquid bath (550), whereby a first copper metal composition with a high copper metal content (22) and a third solder refining slag (23)
BE2018 / 5875
139 are formed, followed by separating the third solder refining slag (23) from the first copper metal composition with a high copper metal content (22).
[28]
The method of claim 27, further comprising the following step:
m) partially reducing (900) the third solder refining slag (23), thereby forming a second diluted copper metal composition according to any of claims 1 to 10 (11) and a fourth solder refining slag (24), followed by the separating the fourth solder refining slag (24) from the second diluted copper metal composition (11).
[29]
The method of claim 28, further comprising the following step:
n) partially reducing (1000) the fourth solder refining slag (24), thereby forming a second raw solder metal composition (26) and a fifth solder refining slag (27), followed by separating the second raw solder metal composition (26) from the fifth solder refining slag (27).
[30]
The method of claim 29, further comprising the following step:
o) partially reducing (1100) the fifth solder refining slag (27), thereby forming a third lead-tin-based metal composition (29) and a third spent slag (28), followed by separating the third spent slag (28) of the third metal composition on a lead-tin basis (29).
[31]
The method of claim 30, further comprising the following step:
p) partially oxidizing (1200) the third lead-tin-based metal composition (29), thereby forming a fourth lead-tin-based metal composition (21) and a sixth solder refining slag (14),
BE2018 / 5875
140 followed by separation of the sixth solder refining slag (14) from the fourth lead-tin-based metal composition (21).
[32]
The method of claim 31, further comprising the following step:
q) recycling (1201) at least a portion of the sixth solder refining slag (14) to step d) (500), optionally by adding at least a portion of the sixth solder refining slag (14) to the first liquid bath (450 ) before oxidizing the first liquid bath (450) in step d) (500), and / or recycling (1201) at least a portion of the sixth solder refining slag (14) to step e).
[33]
The method of claim 31 or 32, further comprising the following step:
r) recycling (1202) at least a portion of the fourth lead-tin-based metal composition (21) to step 1) (800), optionally by adding at least a portion of the fourth lead-tin-based metal composition (21) ) to the second liquid bath (550).
[34]
The method of any one of claims 30 to 33, wherein step o) (1100) comprises adding a sixth reducing agent (R6) to step o) (1100).
[35]
The method of claim 34, wherein the sixth reducing agent (R6) comprises a metal that has a higher affinity for oxygen under the conditions of the method than tin, lead, copper, and nickel, wherein the sixth reducing agent (R6) at preferably iron metal, more preferably scrap iron.
[36]
The method of any one of claims 30 to 35, wherein step o) (1100) comprises adding a second copper-containing fresh feed (55) to step o) (1100).
[37]
The method of claim 36, wherein the second copper-containing fresh feed (55) comprises black copper and / or spent or rejected copper anode material.
[38]
38. The method of any one
BE2018 / 5875
141 of claims 29 to 37, wherein step n) (1000) comprises adding a fifth reducing agent (R5) to step n) (1000).
[39]
The method of claim 38, wherein the fifth reducing agent (R5) comprises a metal that has a higher affinity for oxygen under the conditions of the method than tin, lead, copper, and nickel, wherein the fifth reducing agent (R5) at preferably iron metal, more preferably scrap iron.
[40]
The method according to any of claims 29 to 39, wherein a second Pb and / or Sn containing material (25) is added to step n) (1000), wherein the second containing Pb and / or Sn material (25) preferably comprises scratch, and more preferably is scratch obtained from downstream processing of a concentrated stream of Pb and / or Sn.
[41]
The method of any one of claims 28 to 40, further comprising the following step:
s) recycling (901) at least a portion of the second diluted copper metal composition (11) formed in step m) (900) to step c) (400), and / or recycling at least a portion of the second diluted copper metal composition (11) to step d) (500), and / or recycling at least a portion of the second diluted copper metal composition (11) to step d) (500), and / or recycling at least a portion from the second diluted copper metal composition (11) to the first liquid bath (450).
[42]
The method of any one of claims 28 to 41, wherein step m) (900) comprises adding a fourth reducing agent (R4) to step m) (900).
[43]
The method of claim 42, wherein the fourth reducing agent (R4) comprises a metal that has a higher affinity for oxygen than tin, lead, copper, and nickel under the conditions of the method, wherein the fourth reducing agent (R4) at preferably iron metal, more preferably scrap iron.
[44]
The method of any one of claims 11 to 43 wherein, at least one of the process steps
BE2018 / 5875
142, which involves the separation of a slag phase from a metal phase, an amount of silicon dioxide is added, preferably sand.
[45]
The method of any one of claims 11-44 wherein a black copper or a black copper composition is added to at least one of steps b) (100), f) (700) and o) (1100) wherein the black copper (1, 50, 55) is produced by a step in a smelting furnace.
[46]
The method of any one of claims 11 to 45 wherein at least one of the first raw solder metal composition (18) and the second raw solder metal composition (26) is pre-refined using silicon metal to produce a pre-refined solder metal composition.
[47]
The method of any one of claims 11 to 46 further comprising the step of cooling the first raw solder metal composition (18) and / or the second raw solder metal composition (26) and / or the pre-refined solder metal composition to a temperature of at most 825 ° C to form a bath containing a first surfacing scratch, which comes to float by gravity on a first liquid molten updated soldering phase.
[48]
The method according to any of claims 11 to 47, further comprising the step of adding an alkali metal and / or an alkaline earth metal, or a chemical compound comprising an alkali metal and / or an alkaline earth metal, to the first crude solder metal composition (18) and / or to the second crude solder metal composition (26) and / or to the pre-refined solder metal composition and / or to the first liquid molten updated solder phase to form a bath containing a second supernatant scratch comes to the surface on a second liquid molten updated soldering phase.
[49]
The method of the preceding claim, further comprising the step of removing the second
BE2018 / 5875
143 supernatant scratch of the second liquid molten updated solder phase, thereby forming a second updated solder.
[50]
The method of any one of claims 47 to 49, further comprising the step of removing the first superficial scratch from the first liquid molten updated solder phase, thereby forming a first updated solder.
[51]
The method of claim 49 or 50, further comprising the step of distilling the first updated solder and / or the second updated solder, wherein lead (Pb) is removed from the solder by evaporation and a distillation top product and a distillation bottom product become obtained, preferably by vacuum distillation.
[52]
The method of the preceding claim, wherein the distillation bottoms product comprises at least 0.6% by weight of lead.
[53]
The method of any one of claims 11 to 52 wherein at least a portion of the method is electronically monitored and / or controlled.

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法律状态:
2019-08-19| FG| Patent granted|Effective date: 20190708 |

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EP17207367.8|2017-12-14|

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EP17207367|2017-12-14|

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