• 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:
    Sponge iron is carburized in the cooling zone of a vertical shaft iron ore reduction reactor by causing a carbon-containing gas to circulate in a closed loop including the cooling zone of the reactor and an external conduit containing a quench cooler and a pump. Improved control of the carburization of the sponge iron is achieved by measuring the specific gravity of the circulating gas and using the measured specific gravity value as a control variable effectively to regulate the flow of make-up carbon-containing gas to the cooling loop.
    公开号:SU963475A3
    申请号:SU802937832
    申请日:1980-06-23
    公开日:1982-09-30
    发明作者:Рамон Мартинез-Вера Энрике；Доминго Беррун-Кастанон Джордж
    申请人:Ильса С.А. (Фирма)；
    IPC主号:
    专利说明:

    Consequently, it is theoretically possible to charge an electric furnace with a sponge iron, for example, with an 85% metallization, and to add a sufficient amount of elemental carbon to the furnace charge to react with the remaining oxygen in the iron ore.  However, it is difficult to ensure close contact between elemental carbon and sponge iron particles, in particular because carbon has a much lower density than iron tends to separate from it.  This is achieved by cementation of the sponge iron in the reducing reactor.  Thus, the reduction reactor can operate in such a way that sponge iron is produced.  will be cemented to form iron carbide. In general, the carbon content in the spongy iron is generally in most cases 1% by weight. %  Such cementation may occur in the sludge recovery zone in the cooling zone or in both zones.  The closest to the technical essence and the achieved result | ЯВ / 1 is the method of obtaining spongy (iron from ores in the form of particles, including countercurrent movement of ore and circulating reducing gas, cooling and cementation of spongy iron by carbon-containing gas circulating in the cooling zone and the external circuit by cooling and enrichment with fresh gas 2J. In the cooling zone of the reduction reactor, the regime may be maintained so that the sponge iron particles will be cemented as they cool.  Such cementation can be achieved by using carbon-containing gas, which at a temperature of, for example, 00-700 ° C, reacts with sponge iron with obr. iron carbide, which is largely concentrated in the outer parts of the sponge iron particles.  Both the grouting function and the cooling function in the cooling zone are essential.  If the resulting sponge iron is not sufficiently cooled before encountering atmospheric air, it may be oxidized repeatedly.  Cooling & should be appropriately. change. and be controlled by circulating cooling gas in a circuit that is included in the cooling zone of the reactor, and by changing the recirculation rate or temperature of the cooling gas, or both, a predetermined degree of cooling is provided.  The degree of cementation can be conveniently controlled by controlling the composition of the gas.  Obviously, in optimizing the cooling rate and the degree of cementation in the cooling zone, two separate controlled variables should be controlled.  Such independent control is carried out with the aid of a cooling circuit, the cooling gas is recirculated through the secondary gas, and the cooling gas is supplied and.  output from the circuit.  A predetermined adjusted flow of cooling gas with a predetermined composition is supplied to the circuit, and the desired control is achieved in two ways.  Under one option, fresh cooling gas is supplied to the circuit at a constant rate and the pressure differential between the reduction and cooling zone is measured, which is used as a control variable to regulate the flow of exhaust gas from the cooling circuit. between the regeneration and cooling zones is minimized to prevent a change in the composition of the circulating cooling gas by the E-zone Pelvic Flow.  In the second embodiment, the exhaust gas flow is regulated in such a way that the fresh gas supplied to the circuit is approximately equal to the exhaust gas flow | removed from the cooling circuit.  Although control systems provide: greater control of cooling and carburization, they need to be improved.  As indicated, the degree of carbonization of sponge iron largely depends on the composition of the cooling gas.  Consequently, the control variable used should be more closely interconnected with the composition of the cooling gas compared to the control systems used previously.  The purpose of the invention is to improve the accuracy of controlling the degree of cementation of sponge iron.  This goal is achieved by the fact that in the method of producing sponge iron from ores in the form of particles, including countercurrent movement of ore and circulating reducing gas, {cooling and cementation of sponge iron with carbon-containing gas circulating in the cooling zone and the external circuit with cooling and enrichment fresh gas, the degree of cementation is controlled by changing the rates of gas supply and removal, while maintaining the specific gravity of the cooling gas at a constant level.  The rate of supply of carbonaceous gas to the cooling zone of the regulator: the rate of addition of fresh carbon-containing gas and the rate of water depending on the specific gravity of the circulating cooling gas.  The gas removed from the cooling zone is heated and combined with a reducing gas fed to the reduction zone, while the specific weight of the cooling gas is maintained by adding carbon-containing gas from the recovery zone or fresh.  The specific gravity of the circulating gas is measured in the external pipeline after it is cooled.  The specific gravity of the cementing gas used in the cooling zone is functionally related to the degree of cementation that is imparted to the bladder passing through this zone and, therefore, the specific gravity of the gas can be effectively used as a control variable to control the cementation of the resulting spongy gland.  FIG.  1 depicts a vertical shaft indirect recovery system with a moving bed (preferred embodiment of the process).  ba); in fig.  2 shows a modification of the system in which the exhaust gas is vented from the cooling circuit at a point after adding fresh reducing gas to the circuit; in fig.  3 - a graph of the relationship between specific gravity and degree of carbonization (in percent).  FIG.  1 shows a vertical shaft reduction reactor 1 having an oxidation zone 2 in the upper part and a cooling zone 3 in the lower part.  The ore to be reduced enters the reactor through inlet connection k located in the upper part of the reactor and the sponge iron is discharged from the reactor in the bottom zone through the discharge connection 5Rud is reduced in the reduction zone 2 of the reactor using a hot reducing gas, consisting mainly of from carbon monoxide and hydrogen.  The reducing gas can be obtained from any suitable source.  For example, it may be a reformed gas obtained by catalytic conversion of a mixture of steam and natural gas in a known manner or coke oven kiln gas may be used.  The reducing gas enters the system through pipeline 6 and beyond; through pipe 7 with an 8-flow regulator into the system’s reducing gas circuit.  More precisely, the reducing gas flows from line 7 through line 9 to a coil-type heater 10, which can. heat by burning gas or some other method to increase the temperature of the reducing gas to about ry to SSO-SSO C.  Hot gas from heater 10 is fed into the reactor through line 11 and further into an annular chamber 12 formed by an internal cylindrical baffle 13 and a wall of the reactor.  The hot reducing gas flows upward through the ore layer in the reduction zone 2 and leaves the reactor through pipeline N.  The ore in the reduction zone is mainly reduced to sponge iron.  The waste gas stream from the reactor is pushed through line 14 to the irrigation cooler 15 in which the gas is cooled and dehydrated due to direct contact with the cooling water.  From the irrigation cooler 15, the cooled gas flows along; Steps through conduit 16 to the suction side of pump 17 and then into conduit 9 to replenish the reducing gas circuit.  The amount of gas circulating through the reducing / gas circuit by means of a pump 17 is regulated by means of a bypass 18 located around the pump and having a flow controller 19.  A certain amount of waste gas from the reduction zone of the reactor is removed from the reducing gas circuit through a conduit 20 containing a check valve 21 and a back pressure regulator 22.  Gas escaping from the system through conduit 20 may be used as a fuel, for example in heater 10 and for other necessary purposes or for storage.  The cooling zone 3 of the reactor also forms part of the gas flow loop, and carbon-containing cooling gas Yu circulates through this loop to effect the cementation of the metal-containing material in the cooling zone.  Carbonaceous gas used for cementation. metal-containing material in the cooling zone, can be used with the same composition as the reducing ha. W, used-.  ny in the recovery zone.  More precisely, a portion of the reducing gas entering the system through conduit 6 can flow through conduit 23 containing the regulator; flow, in the pipeline 25 of the cooling gas circuit.   The gas entering through line 25 is fed to the bottom of the cooling zone of the reactor. . The reactor has an internal reflective partition 26 in the shape of a truncated cone, which connects to the wall of the reactor and forms an annular space 27 into which circulating cooling gas is fed through pipe 25.  The cooling gas flows up through the layer of reduced ore in zone 3 of the cooling. - 1 day in the annular space 28 formed by the wall of the reactor and another annular reflective partition 29 in the shape of a truncated cone.  As the carbon-containing gas enters up through the cooling zone 3.  it reacts and cements the spongy iron found there, and also cools it.  From the annular space 28, the gas leaves the reactor through line 30 and enters through a cooler 31, in which it is cooled and dehydrated due to direct contact with cooling water.  The cooled gas stream from the cooler 31 flows through the pipe 32 towards the suction side of the pump 33 and then into the pipe 25 to replenish the co. cooling chambers.  Gas recirculation through the circuit by pump 33 is regulated by means of a bypass 3 located around 9631-5.  .  8 pump and equipped with a flow control 35.  The invention is based on the fact that the degree of cementation occurring in the cooling zone of the reactor can be effectively controlled by measuring and controlling the specific gravity of the circulating gas.  The measured specific gravity value can be used in several ways to effectively control the addition of carbon-containing gas to the cooling circuit.  In one embodiment of the process (FIG.  1) a given constant stream of fresh carbon-containing gas is supplied to the cooling circuit through line 23 and the composition of the gas in the cooling circuit is changed by changing the intrazonal flow between the reduction zone and the cooling zone.  Insofar as . such an intrazonal flow cannot be produced or directly controlled, an indirect method of flow control is required.  More specifically, in the system of FIG. 1, the specific gravity of the gas entering through conduit 25 is measured using a conventional BW device for determining the specific gravity or in a known manner can be measured by the composition of the gas.  The measured value is used to regulate the valve 37 in the pipe Z.  through which gas is withdrawn from the circuit: cooling.  Thus, by adjusting the flow of the exhaust gas from the cooling circuit by means of the valve 37, it is possible to indirectly regulate the intrazonal gas flow.  Fresh carbon-containing gas.  given to the system (FIG.  1), can be used both as a reducing gas in the reduction zone 2 and as a cooling gas in the cooling zone 3.  Consequently, the gas withdrawn from the cooling circuit through conduit 38 has a significant reducing value and is preferably supplied to the reducing gas circuit by connecting the conduit 38 with the recovery line 9m 9.  The following is a representative gas composition in mole percent.  the dry residue that can be detected in different parts of the system (fig.  1), in addition, the corresponding specific weights are shown (A is the composition in pipeline 23; B is the composition in pipeline 25; C is the composition in pipeline 30 and O is the composition in the pipeline 11 k3 СН. 6 18 209 Specific weight 0,33 0,277 0,2bЗ 0,635 Срстав Таз and specific weight, given above, can provide in the system (FIG.  1) cementation of sponge iron about 2%.  It has been established that the percentage of cementation of sponge iron depends on a given weight of carbon-containing gas entering through the cooling zone, and that the relationship between specific gravity and cementation is a function of pressure 1.  On the graph (FIG.  3) The approximate relationship between specific gravity and cementation of sponge iron in the system is shown (FIG.  1) when working with a pressure of 2 kg / cm.  Since the relationship between grouting and specific gravity is affected by a number of process variables, such a relationship must be experimentally determined for each system, including operating conditions.   From the foregoing, it follows that the gas entering through the cooling circuit contains approximately 70 hydrogen and 30% of a mixture of carbon monoxide, carbon dioxide and methane.  Since the carbon-containing gas is consumed in the cementation process, its specific content decreases as the reaction proceeds.  Therefore, to maintain stable conditions, a gas with a relatively large proportion of carbon-containing components and a corresponding relatively high specific gravity can be added to the cooling circuit.  Hot can be served necessary. Fresh gases containing carbon monoxide and carbon from an external source to the cooling circuit have been found to work more efficiently by using at least a portion of the gas having a composition gas that is fed to the reduction zone.  The gas supplied to the lower part of the reduction zone has a content of carbon monoxide, carbon dioxide and methane, which is higher than the content of these components in the fresh reducing gas.  Consequently, the gas in the reduction zone is a more efficient agent than fresh regenerating gas to increase the specific gravity and the efficiency of carburizing the gas entering through the cooling circuit.  In accordance with a preferred embodiment of the method in the system (FIG.  About the flow of fresh gas supplied to the cooling circuit and the gas flow coming from the cooling circuit are adjusted so that a certain amount of gas is released from the recovery zone of the reactor down to its cooling zone.  To this end, the flow of fresh reducing gas flowing through the gas stream entering through conduit 38 is regulated so that gas of relatively high specific gravity from the reduction zone flows down to the cooling zone.  By means of measuring the specific gravity of the gas flowing through the cooling zone and using a specific specific gravity value as a control variable to regulate the flow of gas exiting the cooling circuit, a higher specific gravity gas flow from the reduction zone to the cooling zone is regulated indirectly in order to maintain the specific gravity of the gas; In the cooling zone, it is necessary to achieve the required degree of cementation passing through the sponge iron zone.  It is obvious that the gas is effectively removed from the cooling coil because of: a) the cementation of sponge iron by the equation 2CO C + CO; c) condensation of water vapor in the refrigerator 31 and c) gas flow out through pipeline 38.  Under certain conditions, the sum of a and c may be less than the fresh gas entering the circuit. through pipeline 23.  Thus, it is possible to have a lower and upper intrazonal flow between the reduction and cooling zones.  11 s The system in FIG.  2 is similar to the system in FIG.  one.  The reactor 39 has a recovery zone kQ in the upper part and a cooling zone / in the lower part.  The reducing gas enters the system through pipe 1 and then through pipe tZ towards the suction side of the pump k3, with which it is pumped through pipe kk to the lower part of the cooling zone.  The cooling gas flows up through the cooling zone 45, then is fed from the reactor through line 46 to the cooler 47, from which it is recirculated through line 48 back to the pump 43.  A device 49 for measuring the specific gravity, similar to the corresponding device 38 (FIG.  1) / of-, measures the specific gravity of the gas between the discharge side of the pump and the reactor.  However, in the system (FIG.  1) a fixed supply of fresh gas is connected to the suction side of the pump. 43, not with his graduation party.   is continuously withdrawn from the cooling circuit through conduit 50 containing the adjusting valve 5 and the output of the specific gravity metering device 49 is used to adjust the position of the valve 51. Thus, as well as in the system (Fig.  1), the measured specific gravity of circulating gas is used to regulate the flow of flue gas from the cooling circuit and thus indirectly regulates the flow of gas entering the circuit, which is rich in cementitious constituents.  . The invention is based on the fact that the degree of cementation of iron sponge in the reactor cooling zone can be controlled by measuring the specific gravity of the circulating gas and the measured specific gravity value can be used as a control variable to effectively control the rate of addition of carbon-containing gases to the cooling gas in the loop.  6 in accordance with a preferred embodiment of the method, the regulation is carried out indirectly: BUT by using the measured value of specific gravity to regulate the flow of the outgoing gas out of the counter.  However, the flow of exhaust gas. and from: the circuit can be maintained on by. at a constant level, and the output stream from s of the specific gravity measurement device can be used to regulate the fresh gas stream or, if necessary, the ratio of fresh gas to flue gas stream.  In this case, the size of the intrazonal reducing gas flow through the reactor can be achieved by appropriate relative control of the fresh and waste gas flows.  claim 1.  The method of obtaining sponge iron from ores in the form of particles, including countercurrent movement of ore and circulating reducing gas, cooling and cementation of sponge iron with carbon-containing gas circulating in the cooling zone and the external circuit with cooling and enrichment with fresh gas, characterized in that regulating the degree of cementation, it is regulated by changing the speed of the gas supply and the excess of gases while maintaining the specific gravity of the cooling gas at a constant level.   2 The method according to claim.  1, characterized in that the rate of supply of carbon-containing gas to the cooling zone is controlled by the rate of addition of fresh carbon-containing gas and the rate of removal, depending on the specific gravity of the circulating cooling gas.  3 The method according to claim.  2, characterized in that the gas removed from the cooling zone is heated and combined with a reducing gas fed to the reduction zone.  four. The method according to paragraphs.  1-3, characterized in that the specific gravity of the oh-hardening gas is maintained by the addition of carbon-containing gas from the reduction zone — or fresh.  five. The method according to paragraphs.  1-4, characterized in that the specific gravity of the circulating gas is measured in, 1: the external pipe after it is cooled.  Sources of information taken into account during the examination 1. Pokhvisnev L.  AND.  and etc.  Introduced iron production abroad.  M.  , Metallurgists, 1964, p.  126-159.  2 US Patent No. 3765872, cl.  75-34, 1974.
    srig.1
    权利要求:
    Claims (5)
    [1]
    Claim
    1 . A method of producing sponge iron from particulate ores, including countercurrent movement of ore AND circulating reducing gas, cooling and cementing of sponge iron with carbon-containing gas 20 circulating in the cooling zone and the external circuit with cooling and enrichment with fresh gas, characterized in that, for the purpose of increase the accuracy of regulation of the degree of cementation 25, it is regulated by changing the speed! “Gay supply and removal of gases while maintaining the specific gravity of o / cooling gas at a constant level,”
    [2]
    2. The method of pop. 1, characterized in that the rate of supply of carbon-containing gas to the cooling zone is controlled by the rate of addition of fresh carbon-containing gas and the rate of discharge, depending on the specific gravity of the circulating cooling gas.
    [3]
    3- Pop Method 2, characterized in that the gas removed from the cooling zone is heated and combined with the reducing gas supplied to the reduction zone.
    [4]
    4. The method according to PP. 1-3, characterized in that the specific gravity of the cooling gas is supported by the addition of carbon-containing gas from the recovery zone · or fresh.
    [5]
    5. The method according to PP. 1-4, characterized in that the specific gravity of the circulating gas is measured in the outer pipe after cooling.
    类似技术:
    公开号 | 公开日 | 专利标题
    SU963475A3|1982-09-30|Method for making spongy iron
    US4046557A|1977-09-06|Method for producing metallic iron particles
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    RU2125098C1|1999-01-20|Method of direct reduction of material containing iron oxides and plant for method equipment
    US4150972A|1979-04-24|Controlling carburization in the reduction of iron ore to sponge iron
    US3827879A|1974-08-06|Method for the gaseous reduction of metal ores
    EP0262353B1|1992-03-18|Method for producing hot sponge iron
    CA1153559A|1983-09-13|Method for the gaseous reduction of metalores using reducing gas produced bygasification of solid or liquid fossil fuels
    US1864593A|1932-06-28|Method of producing metal sponge
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    IL45830A|1977-03-31|Method for gaseous reduction of metal ores
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    GB2188067A|1987-09-23|Increasing carbon content of direct reduced iron
    US4067728A|1978-01-10|Method for gaseous reduction of metal ores
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    US2799576A|1957-07-16|Process for operating shaft blast furnaces
    SU639485A3|1978-12-25|Device for obtaining sponge iron
    US4049440A|1977-09-20|Method for producing metallic iron pellets
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    同族专利:
    公开号 | 公开日
    FR2463815A1|1981-02-27|
    GB2058139A|1981-04-08|
    MA18865A1|1980-12-31|
    GB2058139B|1900-01-01|
    DD151768A5|1981-11-04|
    SE8004625L|1981-02-21|
    IT8049026D0|1980-06-20|
    IT1143923B|1986-10-29|
    GR69632B|1982-07-06|
    DE3023121C2|1985-06-13|
    ES492768A0|1981-05-16|
    IN152563B|1984-02-11|
    JPS5629610A|1981-03-25|
    JPS5818962B2|1983-04-15|
    EG14430A|1984-06-30|
    CA1149176A|1983-07-05|
    DE3023121A1|1981-03-26|
    MX155373A|1988-02-24|
    US4224057A|1980-09-23|
    FR2463815B1|1985-03-29|
    ZA803033B|1981-05-27|
    ES8105396A1|1981-05-16|
    BR8003887A|1981-04-22|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
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    US2873183A|1954-07-07|1959-02-10|Kenneth B Ray And The St Trust|Continuous iron ore reduction process|
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    DE1201377B|1961-11-23|1965-09-23|Huettenwerk Oberhausen Ag|Process and plant for the production of iron sponge from iron ore in a reduction shaft using reducing gas|
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    US4054444A|1975-09-22|1977-10-18|Midrex Corporation|Method for controlling the carbon content of directly reduced iron|
    US4150972A|1977-11-17|1979-04-24|Fierro Esponja, S.A.|Controlling carburization in the reduction of iron ore to sponge iron|GB2084610B|1980-09-29|1983-10-12|Woods Jack L|Anodic oxidation of aluminium and aluminum alloys|
    US4584016A|1982-03-23|1986-04-22|Hylsa, S.A.|Method for controlling metallization and carburization in the reduction of metal ores to sponge iron|
    US4528030A|1983-05-16|1985-07-09|Hylsa, S.A.|Method of reducing iron ore|
    DE3317701C2|1983-05-16|1986-08-07|Hylsa S.A., Monterrey, N.L.|A method of operating a vertical shaft moving bed reduction reactor for reducing iron ore to sponge iron|
    DE3437913C2|1984-10-12|1987-05-07|Korf Engineering Gmbh, 4000 Duesseldorf, De|
    US4734128A|1985-09-23|1988-03-29|Hylsa, S.A.|Direct reduction reactor with hot discharge|
    US4897113A|1985-09-23|1990-01-30|Hylsa, S.A.|Direct reduction process in reactor with hot discharge|
    US4752329A|1986-03-21|1988-06-21|Midrex International B.V. Rotterdam, Zurich Branch|Apparatus and method for increasing carbon content of hot directly reduced iron|
    US4702766A|1986-03-21|1987-10-27|Midrex International, B.V. Rotterdam, Zurich Branch|Method of increasing carbon content of direct reduced iron and apparatus|
    AT402938B|1994-06-23|1997-09-25|Voest Alpine Ind Anlagen|METHOD AND SYSTEM FOR DIRECTLY REDUCING METHOD AND SYSTEM FOR DIRECTLY REDUCING MATERIAL IN IRON OXIDE MATERIAL IN IRON OXIDE|
    CN1995402B|2006-01-06|2011-11-16|伊尔技术有限公司|Method for directly reducing iron oxide to metallic iron by using coke oven gas and the like|
    US10316376B2|2015-06-24|2019-06-11|Midrex Technologies, Inc.|Methods and systems for increasing the carbon content of sponge iron in a reduction furnace|
    US10508314B2|2015-06-24|2019-12-17|Midrex Technologies, Inc.|Methods and systems for increasing the carbon content of sponge iron in a reduction furnace|
    JP2017082312A|2015-10-30|2017-05-18|株式会社神戸製鋼所|Method for producing direct-reduced iron|
    DE102019217631A1|2019-11-15|2021-05-20|Thyssenkrupp Steel Europe Ag|Process for the direct reduction of iron ore|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    US06/067,665|US4224057A|1979-08-20|1979-08-20|Method for carburizing sponge iron|
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