• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    If carbon steel and alloyed stainless steel are annealed, rolled or welded at high temperatures, a layer of scale forms. It consists of iron oxide and oxides of the other metal composition corresponding to the steel alloy. The scale adheres firmly to the steel and cannot be completely removed mechanically. This must therefore be removed chemically. A pickling solution with nitric acid (HNO3) and hydrofluoric acid (HF) is traditionally used in stainless steel production. This mixed acid usually contains 100 g to 150 g HNO3 and 30 g to 80 g HF per liter. Pickling takes place between 30 ° C and 70 ° C, depending on the product mix and process. Both acids are aggressive and also chemically dissolve the steel. In the mixed acid, the nitric acid acts as a strong oxidizing agent. This oxidizes alloy components such as iron, nickel and also - only more slowly - chromium, while at the same time decomposing to form NOX gas. The fluoride ions in hydrofluoric acid ensure that the metal ions form complexes and are kept in solution. Since the boundary layer now contains less chromium than the alloy, it is more likely to be chemically dissolved by the mixed acid. This device or process shows a new technology with which alloyed stainless steels can be gently, quickly and efficiently freed from the surface of the steel without the disturbance of NOx formation during the pickling process. The invention relates to a method and device for pickling the surfaces of metallic strips or piece goods, in particular made of carbon steel or stainless steel alloys, and is characterized in that the direct application of the electrical direct current to the anode, which is the material to be treated at the same time, On the one hand, oxygen is generated in statu nascendi, and at the same time the physical detonation of the metal oxides on the surface of the material, which enables chemical pickling of metal surfaces, with a semipermeable membrane on the cathode side, which separates the hydrogen that is produced and derives it from the pickling process. The generation of the extremely reactive atomic oxygen at the anode (steel strip, steel plate or piece goods) thus replaces the HNO3, with the pickling solution forming the metal complexes and thus freeing the surface of the stainless steel from scale. The cathode itself is made of open-pored and / or porous, acid-resistant, electrically conductive metals, generally also called hybrid foam. This cathode is encased in the cathode cell with a semipermeable membrane so that the hydrogen production, which inevitably occurs during electrolysis, happens separately and can be derived from the pickling system. This semi-permeable membrane is intended to prevent the storage of H2 in the material to be pickled, so that the metal cannot become brittle. The pickling solution (mineral acids such as HF, HNO3, H2SO4, H3PO4, HCl and the possible mixture thereof or e.g. also the neutral salt such as Na2SO4, K2SO4) serves here as a transport medium for the electrical direct current and at the same time as a pickling solution for chemical dissolution on the surface of the scale in the stainless steel. The scale in turn consists of oxides of iron and their accompanying or alloying elements of stainless steel, such as. Cr, Ni, V, Ti, Nb, Ta, Mo, W and similar alloy elements. In order to increase the conductivity of the circulating electrolyte, carboxylic acids and / or alcohols can be added, so that the current yield is increased at the same time. These electrolysis salts are destroyed by the electrolysis, but they do not leave any residues that could possibly have a disruptive effect when the old acid is regenerated. The flow of the electrolyte or the pickling solution across the strip path simultaneously creates mechanical turbulence at the side edges and surface of the coil via the electrically insulating spacers, which enormously supports the detachment of the scale. At the same time, ascorbic acid is separately introduced into the circulation tanks of the pickling or electrolyte solution, which also enables the chemical reduction of the chrom6 +, which is toxic to humans, to the harmless chrom3 +.
    公开号:AT523081A1
    申请号:T602292019
    申请日:2019-10-15
    公开日:2021-05-15
    发明作者:Joao Horn；David Dr Techn Konlechner
    申请人:David Dr Techn Konlechner；
    IPC主号:
    专利说明:

    In order to achieve a good degree of purity of the cold- or hot-rolled rust- and acid-resistant products or carbon steel, it is essential to remove adhering oxide layers, the so-called scale, which has formed during the previous heat treatment, from their surface during further processing.
    The removal of scale is initially replaced mechanically in the prefabrication, e.g. Sandblasting or scale washing. The remaining scale as well as the annealing scale resulting from the intermediate and final annealing in the further production process is removed by a chemical process of so-called pickling while the scale-covered strips or piece goods pass through several acid baths. The pickling agent used in carbon steel production is an 18 to 20% by weight HCl solution and, in the case of stainless steel products, a preheated acid mixture (mixed acid) consisting of nitric acid (HNO3) and hydrofluoric acid (HF) diluted with water. The effect of temperature in the pickling baths leads to the environmentally harmful and health-damaging reactions of the NO3 anion during the pickling process, resulting in NOx formation. In order to minimize these toxic NOx gases, reducing chemicals such as urea (urea) are added during the pickling process. The NOx is reduced to N2 and H2O0 and discharged from the system, which leads to considerable HNO3 losses, which in turn have to be compensated for by a new purchase of HNO3.
    Subsequently, the used acid is decomposed by the influence of temperature in a reactor in order to regenerate these acid gases again in scrubbing columns, in which case approx. 20 to 30% of the HNO3 used is lost as NOx. This NOx gas has to be reduced to nitrogen using an SCR-DENOX system before it can be emitted into the environment. This procedure inevitably leads to considerable costs, which are caused by the purchase of ENTs, the purchase of operating resources for the DENOX system as well as the initial investment in a DENOX system ...
    The invention relates to a method for pickling and removing the scale from the surfaces of metals, preferably stainless steel products or carbon steel, in which the scaled steel is subjected to a treatment in an electrolytic pickling process with a mineral acid, predominantly hydrofluoric acid (HF). The proposed method consists of electrolysis, with oxygen (in statu nascendi) being generated on the anode side or the cathode consisting of an acid-resistant sintered material such as. WC, SiC or in open-pored and / or porous, acid-resistant, electrically conductive metals, generally also called hybrid foam, which is encased with a semipermeable membrane, so that the resulting hydrogen is separated and removed from the pickling process. Since the direct current is imprinted directly on the anode, which is also the workpiece to be pickled, the resulting oxygen also acts directly on the surface of the material to be pickled and, on the one hand, breaks off the oxide layer and supports it, as is the case with the usual pickling process with mixed acid chemical conversion of oxides to metal complexes.
    This process can of course also be used in push-pull or so-called continuous pickling systems as well as in piece pickling systems, in which case stainless steel strips (coils) are processed. The strips are connected directly as an anode and the cathode is encased in a semipermeable membrane.
    In the stainless steel industry, processes for pickling stainless steel using the neutral electrolyte process have become increasingly popular in recent years. As described, for example, the material is pickled in aqueous solutions of neutral alkali salts of mineral acids and then in aqueous solutions of mineral acids, preferably sulfuric acid, both treatment stages being carried out electrolytically, i.e. with the use of electricity. An aqueous sodium sulfate solution is preferably used as the neutral electrolyte, and the current densities are in the range between 5 and 15 A / dm . Higher current densities are possible in principle, but are not used because of the higher voltage required due to the poor conductivity of stainless steel. The disadvantage of this method lies in the fact that the regeneration of the used electrolyte turns out to be complicated. Thus, the landfill costs are correspondingly high. Practice in laboratory tests has shown that the pickling time can be significantly reduced, in contrast to today's pickling technology, where high-alloy stainless steels are sometimes pickled for a very long time. Of course, it always depends on the material composition of the stainless steel.
    One of the outstanding results of this invention is characterized in that the pickling times are significantly shortened compared to conventional chemical descaling. The reason for this is the formation of highly efficient oxygen in statu nascendi, which replaces the nitric acid (HNOs3) with simultaneous physical detonation of the scale and simultaneous chemical removal or dissolution of the metal oxide from the metal surface.
    A favorable embodiment of the invention is characterized in that a wide variety of mineral acids and / or neutral salt electrolytes, such as Na2SO4, can be used as the electrolyte.
    A favorable embodiment of the invention is characterized in that through the use of a semipermeable membrane on the cathode, the resulting hydrogen is drawn off separately from the pickling system and thus cannot diffuse into the surface of the workpiece to be pickled, so that there is no possible embrittlement of the pickling material comes.
    An important embodiment of the invention is characterized in that the cathode consists of an open-pored and / or porous, acid-resistant, electrically conductive metal, generally also called hybrid foam, and such as, for example. WC, SiC, sintered stainless steel, sintered graphite, electrical corundum, sintered silicon nitride Si3N4 or porous SSiC ceramics can be used, which on the one hand ensure the flow of current and on the other hand, if they are encased with a semipermeable membrane, separates the hydrogen and thus from the pickling or electrolysis system can be derived.
    An advantageous variant of the invention is characterized in that the hydrogen produced is withdrawn from the pickling process by a control device and, if necessary, this is burned without residue outside the pickling sector and thus disposed of.
    An advantageous embodiment of the invention is characterized in that the electrical voltage can be set variably and thus the metallic surface of the strip is also polished if necessary.
    A favorable embodiment of the invention is characterized in that this application of the direct current replaces the HNO3 and thus no measures need to be taken to reduce the otherwise inevitable NOx. The possible use of urea or hydrogen peroxide is completely eliminated during the pickling process. The construction and operation of a DENOX system can also be omitted at this point.
    An advantageous embodiment of the invention is characterized in that the old pickling solution, that is to say the used pickling solution, does not contain any nitrate salts and can thus be regenerated much more cheaply and easily. The energetic expenditures for the hydropyrolyse of the old solutions are lower than with conventional regeneration techniques.
    An advantageous embodiment of the invention is characterized in that it is possible to precisely maintain the concentration of the pickling bath, thereby increasing the
    An important embodiment of the invention is characterized in that mixed acids can also be used as the electrolyte, with the NOx gases oxidizing at the same time due to the evolution of oxygen at the anode, so that apparently less NOx formation occurs compared to state of the art Type of pickling.
    An advantageous variant of the invention is characterized in that carbon steels can also be pickled faster and more effectively, with lower acid volumes at the same time and the regeneration of the used acids being made more economical as a result.
    An important embodiment of the invention is characterized in that the use of organic carboxylic acids and / or such as 1,2 or 3-valent alcohols increases the conductivity of the pickling solution and thus improves the current yield without leaving residues in the pickling solution , as these break down into CO2 and H, O during the electrolysis.
    The most important embodiment of this invention is characterized in that, during the electrolytic pickling of the metal surfaces, the harmful NOx emissions are completely eliminated and the investment in an SCR-DENOX system does not appear to be necessary in order to relieve the environment of harmful NOx exhaust gases.
    The problem with pickling is that the chromium content in the alloyed stainless steel is oxidized to chromium (VI) during the pickling process. The important embodiment of this invention is characterized in that the addition of ascorbic acid reduces the proportion of chromium (VI) that is toxic to humans to chromium (III). The empirical formula shows this reduction: CrO4 ** + 2H * + 1.5 CeH8g06> Cr (OH) 3 + 1.5 CsH606 + H, O. This means that the ascorbic acid is oxidized to dehydroascorbic acid and thus Cr (VI) is reduced to Cr (III) at the same time.
    The retrofitting of the existing pickling plants is to be explained schematically with the aid of the drawing Fig.1. After the strip (2) has been adjusted in the pickling plant (1), this strip (2) is now guided into the pickling basin (13a) via squeeze rollers. On the bottom of the pickling basin (13a) is the cathode (3) which is covered with a semipermeable membrane so that the H; (7) can be removed separately from the pickling system (1). Direct current is applied to the workpiece (2) to be pickled via current rollers (2a), which at the same time represents the anode (2). However, since the metal strip (2) is to be pickled on both sides, a further cathode (3), which is also covered with a semipermeable membrane, is attached. The electrical direct current (R) is impressed on the one hand via the current rollers (2a), which are located in the electrolyte (13), on the strip (2) and, on the other hand, directly on the cathodes (3). During the circulation (13a) of the pickling solution (13), the electrolysis is started and can therefore break off the scale (18) due to the direct formation of oxygen (17) on the top of the material (2) in order to simultaneously convert the metal oxides into metal complexes to guarantee. Here, too, electrically insulating materials are used as spacers in order to avoid an electrical short circuit. The power rollers (2a) are located directly in the circulating pickling solution (13a) and are arranged at relatively small intervals so that the current flow is ensured accordingly. When the material to be pickled (2) is now surrounded by the constantly circulated electrolyte (13) consisting of approx. 50 to 200 g / l HF (hydrofluoric acid), direct current (R) is impressed on the electrodes (2a, 3), which now accelerates the pickling process enormously and removes scale from the surface of the stainless steel or workpiece (2) within a very short time.
    During the electrolysis, the pickling procedure (1) is placed under negative pressure (18) so that the hydrogen (7) produced is brought out of the pickling system (1), thus guaranteeing that it cannot diffuse into the workpiece (2) to be pickled. The direct current (R) can be applied continuously, alternating, pulsating or rising or falling, depending on the nature of the material, as required. The pickling bath temperature also plays an important role, but it should be set between 20 and 90 ° C, depending on the material. Since there is now no HNO3 in the pickling bath (13a), no dangerous NOX gas can arise, which in turn would have to be reduced to nitrogen in an expensive SCR-DENOX system. After the coil (2) has passed several pickling basins, it is rinsed, dried and later rewound.
    The process includes electrolysis, whereby oxygen (in statu nascendi) is generated on the anode side and thus replaces the HNO3 (nitric acid) as an oxidation carrier. The cathode (3), made of porous, acid-resistant material, is enclosed with a semipermeable membrane in order to remove the hydrogen (H2) produced during the electrolysis from the pickling process (1). The H2 is diverted via an extraction system (18) and, if necessary, used or burned, but removed from the pickling process (1). This means that no H2 can get into the surface of the stainless steel (2)
    This process can of course also be used in push or so-called continuous pickling systems, in which case stainless steel strips (2) (coils) are processed. The strips (2) are connected directly as an anode via the current rollers (2a) and a porous and / or sintered material such as. Stainless steel material, SiC, WC, Si3Na, platinum or other materials inert to acids may be considered. It should be noted here that the cathode (3) is enclosed with a semipermeable membrane so that the H2 gas (7) can be diverted separately from the pickling process (1) and flared or, if necessary, stored. The entire pickling process (1) is encapsulated with a cover (11). The suction system (18) brings water vapor, H2 and hydrofluoric acid droplets out of the system. A lift system (9) for the upper cathode (3) is mounted on the cover (11). To prevent an electrical short circuit, an insulating material made of plastic is attached as a spacer between the cathode (3) and anode (2).
    In order to reduce the proportion of chromium (VI) to chromium (III) that is toxic to humans, ascorbic acid dissolved in water is added to the pickling or electrolyte bath (13a) via a dosing unit ().
    The cathode (3) can also be made of inert materials such as. porous and / or sintered materials such as stainless steel material, SiC, WC, Si3Na, platinum or other materials that are inert to acids, if possible as foamed stainless steel material, since this results in a larger electrode surface. This cathode (3) is enclosed with a semipermeable membrane (6), so that the hydrogen H2 produced during the electrolysis can be brought out of the system via an outlet (7) and thus there is no diffusion of H; into the stainless steel to be pickled (2) can come.
    In analogy to the other proposed method or device, FIG. 3 shows a possibility of pickling plates, wires, long goods, tubes, rods, piece goods and / or flat pieces. The work piece (2a) to be pickled is placed in an anode basket (2). This basket (2) is made of stainless steel. Identical in construction, only a cathode basket (3) with a corresponding spacer (4) is attached and immersed in the pickling bath (4). By imprinting the direct current on the anode (2) and cathode (3), which in turn is surrounded by a semipermeable membrane (6) and made of porous and / or sintered materials such as stainless steel material, SiC, WC, Si3Na, platinum or others against acids consists of inert materials, the electrochemical pickling process (1) is now started. Here, too, the resulting hydrogen (7) is drawn off separately from the pickling system (1) by means of negative pressure (8) in order to prevent the diffusion of H; (7) into the workpiece (2).
    This means that the stainless steel product (2a), be it plates, wires, long goods, pipes, rods, piece goods and the like, is placed directly in an "electrode basket" (2). This basket (2) can, for example. can also be made of stainless steel, this basket (2) also serving as an electrode for the direct current (R) used later.
    At the smallest possible distance to the “product electrode” (2), i.e. the electrode basket, the counterelectrode (3) is attached identically so that the spacers (9) ensure the separation between the electrodes (2, 3). The spacers (9) must be made of a non-conductive material, such as. Plastic or similar insulation material must be made so that no electrical short circuit can occur. The cathode side (3) is enclosed with a semipermeable membrane (6) so that no H2 (7) can penetrate into the product (2a) to be pickled. The semi-permeable membrane (6) is constructed in such a way that
    If the material to be pickled (2a) with the two electrode baskets is immersed directly into the electrolysis bath (4), consisting of approx. 15 to 200 g / l HF (hydrofluoric acid), direct current (R) is applied to the electrodes (2 , 3), which now accelerates the pickling process enormously and removes scale from the surface of the stainless steel (2a) within a very short time. The electrolyte (4) is circulated in a pickling basin (1) via a circulation pump (5) in such a way that turbulence is developed within the piece goods (2a) to be pickled during the pickling process.
    The direct current (R) can be applied as required, alternating, continuous, pulsating or rising or falling, depending on the material properties. The pickling bath temperature also plays an important role, but it should be set between 20 and 90 ° C depending on the material.
    Since there is no HNO3 in the pickling bath (4), no dangerous NOX gas can arise, which would have to be reduced to nitrogen in an expensive DENOX system. In order to reduce the toxic proportion of chromium (VI) to chromium (III), an ascorbic acid solution diluted with water is added to the pickling or electrolyte bath (4) via a dosing unit ().
    Fig. 4 now shows schematically a vertically arranged cathode cell (1) to the electrolyte inlet (2) and overflow (3) of the electrolyte (2a) or pickling solution (2a) and the discharge of the H produced; (4) better to explain. The cathode (5) is covered with a semipermeable membrane (5a) and serves on the one hand to separate the hydrogen (4) and on the other hand to support the electrically insulating spacers (7) so that there is no electrical short circuit. The cathode material consists of a porous and / or sintered material such as. Stainless steel, SiC, WC, Si3Na, platinum or other materials that are inert to acids. The electrolyte (2a) flows at the top of the cathode cell (3) vertically between the cathode (5) and anode (6), which at the same time represents the coil (6) to be pickled, and is in turn fed into the cathode cell (2 ) brought in. The direct current is imprinted on the one hand on the cathode (5) and on the other hand directly on the current roller (6a), which at the same time blasts the scale off the surface due to the atomic oxygen produced and thus the chemical conversion of the metal oxides into metal salts takes place more easily. Due to the small distance between the coil and the cathode, the spacers (7) create violent turbulence. which at the same time enormously shortens the pickling time.
    Fig. 5 shows again a vertically arranged cathode cell (1) in order to access the cathode (3) which is encased with a semipermeable membrane (3a) and which is made of a porous and / or
    10719
    权利要求:
    Claims (1)
    [1]
    Claims
    The invention relates to a method and device for pickling metallic strips, plates, wires, long goods, pipes, rods, piece goods consisting of carbon steel material as well as alloyed stainless steel and is characterized in that, due to the direct imprint of the electrical direct current on the anode, which simultaneously is the workpiece to be pickled, on the one hand atomic oxygen is generated and at the same time through the use of a semipermeable membrane on the cathode side, the hydrogen formed during electrolysis is removed separately from the pickling process and thus enables the pickling of the metal surfaces and removal of the residual scale without the effect the storage of hydrogen in the surface of the pickling material.
    Method according to claim 1, characterized in that the cathode is made of an acid-resistant, electrically conductive metal with open pores and / or porous, generally also called hybrid foam such as. Stainless steel, SiC, WC, Si3Na, platinum or other materials that are inert to acids, in order to guarantee the flow of electrical current and thus the resulting H; to be removed separately in the cathode box.
    Method according to claims 1 and 2, characterized in that the current is applied directly to the strip via current rollers or current brushes and on a pair of electrodes, with atomic oxygen being generated at the anode by the anodic oxidation and simultaneously via the cathode hydrogen, which is generated separately is removed from the pickling process.
    Method according to one of Claims 1 to 3, characterized in that a pulsating and / or continuous application of current takes place directly on the electrodes. The method according to claim 1 to 4 is characterized in that for the chemical removal and / or dissolving of the scale, a mixture of 1 to 3-basic mineral acids and water and / or neutral salts diluted in water in the concentration of 5 g / l to 250 g / l mineral acid or neutral salt is used, the concentration of the mineral acids or neutral salts being between 50 and 200 g / l, preferably 100 g / l.
    Method according to Claims 1 to 5, characterized in that the current densities (coulombs per unit area) are set specifically for the strip to be pickled, with current densities at the electrodes between 0.5 and 200 A / dm amounts to.
    The method according to claims 1 to 6 is characterized in that the pickling solution no longer contains any nitrate ions and thus no NOx gas formation can occur, while the scale is physically blown off during the electrolysis and chemical conversion to metal complexes, the surface of the metal is cleaned . The method according to claims 1 to 7 is characterized in that this technique also allows the pickling of carbon steel using 18 to 20% HCI, this mineral acid serving as an electrolyte and at the same time as a pickling solution.
    11.
    12th
    13th
    14th
    15th
    16.
    17th
    18th
    19th
    11
    The method according to claim 1 to 8 is characterized in that this technique also allows mixed acid such as. To use HF / HNO3 and other mineral acid mixtures as electrolyte to pickle alloyed stainless steels as well as carbon steel.
    The method according to claim 1 to 9 is characterized in that conductive salts such as organic carboxylic acids and / or 1,2 and / or trihydric alcohols are added in a concentration of 1 to 250 g / l in order to increase the electrical conductivity of the electrolyte, there is no longer any disruptive residue in the pickling solution after the pickling process.
    The method according to claims 1 to 10 is characterized in that the targeted addition of ascorbic acid chemically reduces the chromium content, which is toxic to humans, to harmless chromium **.
    Device according to the preceding claims from 1 to 11, characterized in that the cathode cell is arranged on the one hand directly in the bottom of a pickling basin and on the other hand in a movable cover so that the strip can be easily and efficiently introduced into the pickling zone and thus the cathode side comes close to the strip possible, moved before the electrolysis process.
    Device according to claim 12, characterized in that the electrodes and the deflection rollers or power rollers are lifted away hydraulically and / or mechanically during the introduction of the strip in order to make this variant easier for push and continuous pickling systems.
    Device according to Claims 11 and 13, characterized in that the temperature is set specifically to the product to be pickled, the electrolyte temperature being between 20 and 90 ° C, preferably 65 ° C.
    Device according to one of Claims 11 to 14, characterized in that electrically insulating spacers are mounted between the product (anode) and electrode (cathode) in order to avoid an electrical short circuit and at the same time to generate turbulence.
    Device according to one of Claims 11 to 15, characterized in that the amount of electrolyte added in the gap between the electrodes and the strip is regulated.
    Device according to one of Claims 11 to 16, characterized in that the current flow to the electrodes is regulated.
    Device according to one of Claims 1 to 17, characterized in that the cathode side is provided with a semipermeable membrane so that the hydrogen produced is drawn off immediately from the pickling process.
    Device according to one of claims 1 to 18, characterized in that the cathode consists of porous and / or sintered, oven-pored acid-resistant material, generally also called hybrid foam, and is mounted directly in the cathode box and is encased in the direction of the anode side with a semipermeable membrane.
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    同族专利:
    公开号 | 公开日
    AT523081B1|2022-02-15|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    CA1044641A|1974-05-28|1978-12-19|Societe D'etude Pour La Regeneration De L'acide Chlorhydrique Seprac|Processes and installations for the regeneration of spent pickling solutions|
    US4713153A|1985-07-12|1987-12-15|N. V. Bekaert S. A.|Process and apparatus for cleaning by electrochemical pickling with alternating current of specified frequency|
    JPH0324299A|1989-06-22|1991-02-01|Kawasaki Steel Corp|Method for pickling band stainless steel|
    RU94022873A|1994-06-15|1996-06-27|В.И. Шумилов|Method and apparatus for continuous pickling of copper|
    WO2005085502A1|2004-03-10|2005-09-15|Andreas Stepan|Method for pickling steels and regenerating pickling solutions|
    WO2008058986A1|2006-11-14|2008-05-22|Danieli & C. Officine Meccaniche S.P.A.|Annealing and pickling process|CN113385478A|2021-06-11|2021-09-14|江苏力源金河铸造有限公司|Process for removing blackening of inner cavity wall of casting part|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    AT602292019A|AT523081B1|2019-10-15|2019-10-15|Pickling steels using a membrane|AT602292019A| AT523081B1|2019-10-15|2019-10-15|Pickling steels using a membrane|
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