DE102015008090A1 - Method and system for operating a Corex or Finex system - Google Patents

Abstract

The invention relates to a method for operating a Corex plant or a Finex plant for producing sponge iron and pig iron having a reduction device and a melt gasifier, in which coking gas is processed and used as reducing gas during operation of the Corex plant or Finex plant. Furthermore, an associated attachment is disclosed.

Description

The present invention relates to a method for operating a reduction device and a melt gasifier having Corex or Finex plant for producing sponge iron and pig iron.

The Corex and Finex processes are a two-stage smelting reduction process in which pig iron based on uncarbored coal and iron ores can be produced. The aim of the smelting reduction process is to produce liquid iron, the quality of which corresponds to blast furnace pig iron, by combining melting process, coal gasification and direct reduction. The smelting reduction combines the process of direct reduction (prereduction of iron oxide to sponge iron) with a melting process (end reduction). The process runs in two stages in separate units. First, the ores are reduced to sponge iron, and in the second step, the final reduction, the melting and the carburizing to pig iron.

Currently, coke oven gas is mostly used for heating purposes and the production of electricity and much less for hydrogen production. In recent years, however, processes have been developed in which Kokereigas in addition to hydrogen and methane is produced. The main drawback of these processes is the enormous expense of cleaning and conditioning the coke oven gas and disposing of the cleaning products as well as the environmental impact of various toxic components. In addition, the energy required for the purification and further processing of the coke oven gas and the production of hydrogen or methane is very large.

The present invention has for its object to provide a method and a system of the type described, which can be realized in a particularly efficient manner.

This object is achieved by a method for operating a reduction device and a melt gasifier having Corex or Finex plant for the production of sponge iron and pig iron, prepared in the Kokereigas and used as a reducing gas in the operation of the Corex or Finex plant.

Furthermore, the above object is achieved by a plant for carrying out this method, which is designed as a Corex or Finex plant and a melt gasifier and above the Schmelzvergasers or next to the Schmelzvergaser arranged reduction device, the plant facilities for the preparation and use of Kokereigas as a reducing gas during operation of the Corex or Finex plant.

According to the invention, a new simple method is provided with which the coke oven gas is processed without great technical effort so that it can be used as a reducing gas for the production of sponge iron and pig iron in a Corex or Finex plant.

In a further development of the method according to the invention, the excess heat / waste heat of the gasification gas, reducing gas, top gas and / or excess gas of the Corex or Finex plant is used to heat the coke oven gas for the production of reducing gas. During the treatment of the coke oven gas toxic components, methane and higher hydrocarbons thereof are decomposed to carbon monoxide and hydrogen.

In a further development of the invention, the Kokereigas is thus for the most part after heating by excess heat of the carburetor or the reduction gas and / or by waste heat of the top gas and / or the excess gas and partly cold the carburetor gas in various aggregates of the Corex or Finix plant fed, recycled to the reducing gas and mixed with the gas used as a reducing agent for the production of sponge iron.

In a specific embodiment, the coking gas gas is mixed with gasification gas and fed as reducing gas to the reduction device.

In a particularly preferred embodiment of the method according to the invention, the Corex or Finex plant is operated with a second reduction device, in particular a DRI reduction device, for the production of sponge iron. In such a Direct Reduced Iron (DRI) plant, sponge iron is produced, in which process at elevated temperatures H ₂ and CO react directly with iron oxides without melting iron ore or pellets.

Objective of the method according to the invention is preferably, the excess heat of the carburetor or reducing gas and the waste heat of the top and excess gas that is wasted in washing and cooling systems, as far as technically and economically useful to use for heating Kokereigas, higher hydrocarbons and methane disassemble and produce from Kokereigas reducing gas, which can be used for the production of sponge iron. By this solution according to the invention, the specific emissions of carbon dioxide per ton of sponge iron and pig iron is greatly reduced. Also the The amount of water in the process water circuit is reduced by more than 50%, which means that the individual units are correspondingly smaller, cheaper, and consume less power.

The additional reduction gas produced in the Corex or Finex coking plant gas leads to better carburization of the sponge iron in the Corex or Finex reduction unit and lower coke consumption in the melter gasifier.

By using coking gas in the Corex or Finex process to produce additional reducing gas, the Corex or Finex plant can also operate on carbon carriers with a low volatiles content, bringing the range of carbon carriers found in the Corex - or Finex process can be used, is significantly expanded.

By this method according to the invention the coking gas is heated by excess heat and by most of the waste heat of the Corex or Finex plant to such a high temperature that methane and higher hydrocarbons introduced with raw materials and formed in the plant water vapor and carbon dioxide under catalytic effect the freshly reduced sponge iron reacted and decomposed to carbon monoxide and hydrogen. In this case, methane and other organic components are decomposed so far that the thus treated Kokereigas, mixed with the carburetor gas, can be used as a reducing gas for the production of sponge iron.

By utilizing the excess and waste heat of the Corex or Finex plant and the carbon dioxide and water vapor present in the gas and the catalytic properties of the freshly reduced sponge iron, this simple treatment of coke oven gas and reducing gas replaces complex purification plants, which serve as a precursor to further processing of the Coke oven gas is required so that it can be used for the production of sponge iron.

By replacing the cooling gas by Kokereigas in the Corex or Finex plant according to the invention is particularly provided to dispense with a complex, high-maintenance internal cooling gas cycle in which much thermal energy is wasted. Instead of the cooling gas, the preheated or cold Kokereigas is supplied to the about 1,050 ° C hot gas to cool it below 900 ° C and at the same time to heat the Kokereigas to the same temperature. It is a part of the excess heat of the gasification gas, which is dissipated via the cooling gas circuit and wasted, used to heat the coking oven gas. The remaining excess heat of the gasification gas, which is also dissipated and wasted through the cooling gas circuit, is utilized for heating by coking gas preheated in the reducing gas heat exchanger, which after further heating is supplied to various areas (aggregates) of the Corex or Finex plant.

Specifically, it is provided that the coker gas heated in the top gas heat exchanger and then heated in the reducing gas heat exchanger via a line to the reducing gas, the dome region of the melt gasifier and the lower portion of the reduction device or the intermediate container or via another line to the gasification gas, via a line and downpipes, so that the heated Kokereigas is heated by mixing with hotter gases and in contact with hotter solid particles to high temperatures and by reactions with carbon dioxide and water vapor higher hydrocarbons and mostly methane to carbon monoxide and hydrogen are decomposed.

By this method, the Kokereigas is heated by excess heat and most of the waste heat of the Corex or Finex plant to such a high temperature that methane and higher hydrocarbons, introduced with raw materials and formed in the plant water vapor and carbon dioxide, under catalytic Effect of freshly reduced sponge iron reacted and decomposed to carbon monoxide and hydrogen. In this case, methane and other organic components are decomposed so far that the thus treated Kokereigas, mixed with the carburetor gas, can be used as a reducing gas for the production of sponge iron.

By supplying the coke oven gas, the hydrogen content in the reducing gas is increased, whereby the performance of the reducing means is increased, since the reduction reactions of the iron oxides by hydrogen are faster than by carbon monoxide. In addition, the temperature increase in the reduction device, which is due to the exothermic reaction of the carbon monoxide with iron oxides and leads to agglomeration, strongly braked by the endothermic reaction of hydrogen with iron oxides. The additional reduction gas produced in the Corex or Finex coking plant gas leads to better carburization of the sponge iron in the Corex or Finex reduction unit and lower coke consumption in the melter gasifier.

Furthermore, it is an object of the invention, the nitrogen, which is used in the Corex or Finex plant for the pneumatic conveying of hot dust and as cooling and purge gas, replace with coke oven gas and reduce the nitrogen content in the top and surplus gas. This results in several advantages, such as increasing the performance of the system, reducing energy losses and reducing nitrogen consumption.

In another embodiment, the reducing gas produced from coking gas is used partly in the Corex or Finex plant and for the most part in a second reduction device, in particular a DRI reduction device, for the production of sponge iron.

In addition to the use of the total excess heat of the Corex or Finex process, which is considerable and is wasted in operating plants, and most of the waste heat of the top and the excess gas, the hybrid process according to the invention brings with it enormous process advantages and reduces significantly the production costs of pig iron and sponge iron and the emission of carbon dioxide per ton of pig iron or sponge iron. It is also a very simple process for treating coke oven gas into reducing gas that can be used to make sponge iron. The toxic constituents of the coke oven gas are decomposed to form carbon monoxide and hydrogen, which must be disposed of in other processes. Furthermore, almost all the chemical energy that is introduced by coal into a coking plant and into the Corex or Finex plant is utilized for the production of pig iron and sponge iron or steel.

The top gas from the Corex or Finex reduction device is preferably supplied after discharge of the waste heat in the heat exchanger, after washing, cooling and compression of a PSA plant in which carbon dioxide is eliminated. The PSA plant is a facility that has the property of permitting smaller molecules, such as H ₂ , N ₂ , CO, to pass through and retain larger and heavier molecules, such as CO ₂ , H ₂ S. PSA means pressure swing adsorption. As is known, the nitrogen is not eliminated in the planned PSA plant. Since its share in the reducing gas for the DRI reduction device should be below 10% for process reasons, the reduction of its share in the top and surplus gas of the Corex or Finex plant leads to a higher degree of utilization of these gases and to the production of a larger amount of sponge iron. The product gas from the PSA plant, to which excess gas is added, is brought to the required temperature in a heat exchanger and then in a direct gas heater before it is fed to the DRI reduction device. In order to protect heat exchangers from "pitting corrosion" the CO rich product gas is supplied to a limited amount of water vapor in order to heat the gas to higher temperatures in the heat exchanger can.

In the method according to the invention, the carbon monoxide- and hydrogen-containing gas, instead of the water vapor, the excess gas cooled in the excess gas and washed in a gas scrubbing excess gas at an elevated temperature, thus also with a higher water vapor content supplied.

This eliminates the need for a steam generating plant and the compression of the excess gas, since its pressure is sufficient for use in the DRI system. In addition, the PSA plant is smaller and cheaper and the power consumption for the compression of the gas for the PSA plant lower. The excess gas may be supplied to the product gas from the PSA plant because its carbon dioxide content is relatively low and need not be excreted in the PSA plant. The limitation on the amount of excess gas supplied to the carbon monoxide and hydrogen-containing product gas, however, depends on the hydrogen sulphide or sulfur content of the sponge iron produced. Too high a value, part of the surplus gas is passed over the PSA unit in the H ₂ S is precipitated.

According to the invention, it is further provided to utilize the waste heat of the top gas from the DRI reduction shaft for heating the carbon monoxide and hydrogen-containing gas from the PSA system and the excess gas from the gas scrubbing, for which purpose a top gas heat exchanger is installed in the top gas line. This reduces the need for fuel gas for the second heat exchanger. In addition, the second heat exchanger, which is made of special steel because of "pitting corrosion", gets smaller and cheaper.

Furthermore, it is preferably provided that the amount of Kokereigases which is supplied to the gasification gas and various aggregates of the Corex or Finex plant, and the temperature of the reducing gas for the reduction devices is adjusted depending on the methane content of the top gas from the DRI reduction device.

According to the invention, the amount of coking gas supplied to the Corex or Finex plant and processed into the reducing gas is limited to about 2% by the methane content of the top gas from the DRI reduction device in order to keep the losses low. In this case, a higher temperature of the reducing gas is desirable, since it leads to a lower methane content of the top gas. In addition, the Reduction device of the Corex or Finex plant operated with a specific high reduction gas quantity in order to minimize the amount of excess gas. This approach is desirable because methane is decomposed by a relatively high proportion of carbon dioxide and water vapor in the reduction device, which are formed by reduction of iron oxides, and by the presence of the catalytically active iron sponge much more in the Corex or Finex reduction device than by Mixing with carburetor and other gases in other units of the Corex or Finex plant. As a result, the methane content of the top gas is much lower than that of the excess gas. By operating this reduction device with a high specific amount of reducing gas, the amount of excess gas becomes smaller and thereby the amount of methane supplied to the DRI system. The specific high reduction gas volume and the resulting high metallization of the sponge iron from the reduction device brings additional process engineering advantages in the operation of the Corex or Finex plant, such as a lower coke content in the coal mixture and less sulfur in pig iron.

The present invention further relates to a plant for carrying out the method described above, which is designed as a Corex or Finex plant and having a melt gasifier and arranged above or next to the melt gasifier reduction means, wherein means for the preparation and use of Kokereigas as reducing gas in Operation of the Corex or Finex plant.

The system designed according to the invention has a melt gasifier to which carbon carriers are fed via a feed system and oxidants via a line. Above or next to the melter gasifier, a reduction device is installed to which iron carriers and surcharges are supplied. The produced sponge iron with aggregates is fed by discharge screws to the melt gasifier and melted down with ash and aggregates. The molten pig iron and slag are periodically tapped at the bottom of the melter gasifier.

In a particularly preferred embodiment of the method according to the invention, the Corex or Finex plant is operated with a second reduction device, in particular a DRI reduction device, for the production of sponge iron. In such a Direct Reduced Iron (DRI) plant, sponge iron is produced, in which process at elevated temperatures H ₂ and CO react directly with iron oxides without melting iron ore or pellets.

Specifically, the system comprises means for heating the coke oven gas by the excess heat / waste heat of the gasifier gas, reducing gas, top gas and / or excess gas of the Corex or Finex and the DRI plant.

Furthermore, it comprises, in particular, means for mixing the coking oven gas with gasification gas.

Specifically, it is provided that the heated in the top and reduction gas heat exchanger Kokereigas is supplied to the gasification gas and various aggregates of the Corex or Finex plant is heated by mixing with hotter gases and in contact with hotter solid particles to high temperatures and by reactions with carbon dioxide and Water vapor, higher hydrocarbons and mostly methane to carbon monoxide and hydrogen decomposes.

The addition of the coke oven gas to the gasification gas and to various aggregates of the Corex or Finex plant is preferably designed so that the excess and waste heat of the Corex or Finex plant is optimally utilized for heating the coking oven gas and for decomposing methane.

The invention will be explained below with reference to an embodiment in conjunction with two drawings in detail. The 1 shows a schematic representation of the structure of a Corex and the 1a a Finex plant. It is actually the same procedure. The only differences between these methods are the particle size of the iron oxides in both reduction devices 4 be used and the type of reduction device 4 , In the Corex plant, the lumpy ore, pellet or other mixture is used as the raw material and fine ore is used as the raw material in the Finex plant. The Corex system is the reduction device 4 around a reduction shaft, from which at the lower end the sponge iron of discharge screws 5 discharged and the melt gasifier 1 is added and in the Finex plant to two series-connected and stacked fluidized bed reactors 4 and an intermediate container 4a from which the sponge iron from a discharge screw 5 discharged and the melt gasifier 1 is added.

The coking gas is fed to the Corex or Finex plant via a pipe 18 , supplied with a pressure about 1 bar higher than the system pressure and added over several lines and aggregates of the Corex or Finex system.

The compressed gas is sent via a pipe 19 and a top gas heat exchanger 20 , by doing it by waste heat of the top gas from a reduction device 4 is heated, and a reduction heat exchanger 22 different units or via a pipe 25 supplied to the gasification gas. The amount of coker gas added to the gasifier gas is adjusted so that the gasification gas is cooled below 900 ° C before it reaches a hot gas cyclone 9 fed and dedusted. The carburetor gas is also cold Kokereigas via a line 34 added if the temperature of the reducing gas before the Heißgaszyklon is too high. The separated hot dust is removed by a compressor 28 compressed to about 6 bar and over a pipe 29 fed coke oven gas to a dust burner 11 pneumatically conveyed and gasified by oxygen. The use of coke oven gas instead of nitrogen has the advantage that the nitrogen content in all gases of the Corex or Finex and DRI plants is substantially reduced and nitrogen consumption is reduced. In addition, the sensible heat of the hot dust for heating and processing of a subset of the coke oven gas is utilized. The in a reducing gas heat exchanger 22 coking gas heated by remaining excess heat of the gasification gas is passed through a pipe 23 the reducing gas, via a pipe 24 and downpipes the Dombereich of the melt gasifier 1 and the lower portion of the reduction shaft 4 or the intermediate container 4a , or via a wire 25 added to the gasification gas. The addition of the heated coke oven gas to the lower portion of the reduction shaft 4 or the intermediate container 4a leads to cooling and to a higher carburization and sponge iron, whereby the agglomeration and failure of the discharge screws 5 is reduced by agglomerates. The over a line 26 the excess gas heat exchanger 27 supplied and heated by waste heat of the excess gas Kokereigas is before entering the reduction device 4 , the reducing gas added to adjust its temperature. That after the reduction heat exchanger 22 branched reducing gas with a relatively low methane content is in the excess gas heat exchanger 27 cooled, in a gas wash 7 washed by water at a higher temperature, thereby with a higher water vapor content via a line 30 the carbon monoxide, hydrogen-containing product gas from the PSA plant 13 fed to the second heat exchanger 14 to protect against "pitting corrosion". The mixed gas is in the top gas heat exchanger 31 and then in the second heat exchanger 14 preheated to about 400 ° C. Heating to a temperature higher than 400 ° C results in "pitting corrosion" due to carbon monoxide. That in the heat exchangers 31 and 14 preheated reducing gas is in the gas heater 15 by adding oxygen through a pipe 32 and partial combustion heated to the required temperature, the reduction shaft 16 supplied and used for the production of sponge iron. The sponge iron is at the bottom of the reduction shaft 16 discharged.

The surplus and waste heat of a Corex or Finex plant is used in the top gas and reduction gas heat exchangers 20 and 22 preheated and the Domegereich the carburetor 1 and the gasifier gas supplied Kokereigas and the dust burner 11 supplied cold Kokereigas heated to a high temperature. This methane and higher hydrocarbons are decomposed by carbon dioxide and water vapor to carbon monoxide and hydrogen so far that the behind the reducing gas heat exchanger 22 diverted reducing gas or excess gas in the DRI plant can be used without further decomposition of methane and higher hydrocarbons for sponge iron production. The in the reducing gas after the reduction gas heat exchanger 22 still existing and that, via the reduction and excess gas heat exchanger 22 . 27 Methane supplied with the coking gas becomes in the reduction device 4 , decomposed by the formed by reduction of iron oxides carbon dioxide and water vapor under the catalytic action of the freshly reduced sponge iron to carbon monoxide and hydrogen. This additional reducing gas will only partially reduce the iron oxides in the reducer 4 exploited the Corex or Finex plant, and the unused carbon monoxide and hydrogen are fed via the top gas and PSA plant of the DRI plant and used for the production of sponge iron. The feed of the coke oven gas with a pressure about 1 bar higher than the pressure of the Corex or Finex system, via a line 18 , The bulk of the coke oven gas is via lines 19 and 26 the top gas and the excess gas heat exchanger 20 . 27 fed. That in the top gas heat exchanger 20 preheated coke oven gas is the reduction gas heat exchanger 22 or via a line 21 supplied to the gasification gas. In the reduction gas heat exchanger 22 The pre-heated coke oven gas is further heated before it is fed through several lines of the Corex or Finex plant. The in excess gas heat exchanger 27 heated Kokereigas is added to the reducing gas and introduced into the reduction device and led out after reduction of the iron oxides as a top gas, in Topgaswärmetauscher 20 cooled, in the gas scrubber 14 washed, from the compressor 12 compressed and fed to the PSA plant.

By feeding the heated coke oven gas via lines 21 or 25 to cool the carburetor gas below 900 ° C eliminates the energy-consuming cooling gas circuit with maintenance-prone rotary piston fans 8th ,

In the case that the temperature of the reducing gas before entering the hot gas cyclone 8th rises to about 900 ° C, the carburetor gas is cold Kokereigas via a line 34 fed. During normal operation, the temperature of the reducing gas is adjusted before the hot gas cyclone 9 and before the reduction device 4 by adjusting individual amounts of coke oven gas through heat exchangers 20 . 22 27 or cold to the Corex or Finex system.

The pneumatic conveying of hot, in hot gas cyclone 9 separated dust to the dust burner 11 done by cold, by a compressor 28 compressed to 6 bar and via a pipe 29 the coke oven gas supplied to the dust return. In addition, it is also envisaged to use the cold, compressed Kokereigas as cooling or flushing medium at several points instead of nitrogen. This results in several procedural advantages, such as lower heat losses, higher system performance and low nitrogen consumption.

To store the excess heat that is present in various areas of the Corex or Finex plant or in areas where the nitrogen is used as the cooling medium, the heated or cold coking gas is fed to these areas or aggregates.

Due to high temperatures of the heated gas, presence of water vapor and carbon dioxide, and catalytic properties of the sponge iron, the coking gas is conditioned to be mixed with gasification gas as the reducing gas in the Corex or Finex and DRI reduction equipment 4 and 16 is used.

The setting of an optimal methane content of the top gas from the DRI reduction shaft 16 is done by adjusting the individual amounts of Kokereigases that are supplied to the gas and the individual aggregates of the Corex or Finex plant, and by adjusting the temperature of the reducing gas for the reduction wells 4 . 16 , The methane content of the top gas from the DRI reduction shaft 16 should be less than 2% by volume. A higher proportion leads to larger losses of this valuable gas, which is branched off with the partial flow of the top gas for heating purposes, in order to limit the nitrogen content in the reducing gas to about 10% by volume. Since more methane is decomposed at higher temperatures, it is advantageous to have the temperature of the reducing gas for both reduction devices 4 and 16 set higher.

Since the methane content of the excess gas is higher than that of the top gas from the reduction device 4 is a high specific reduction gas amount for the reduction device 4 adjusted so that more coke oven gas used in the Corex or Finex plant, processed more reducing gas and more sponge iron is produced.

For producing sponge iron in the DRI reduction device 16 When the system is running, the product gas is removed from the PSA plant 13 used as reducing gas. Because the gas is very rich in CO and when heated in the heat exchanger 14 which leads to "pitting corrosion", is the gas in front of the heat exchanger 14 a limited amount of water vapor supplied to the gas, without damage to the heat exchanger 14 to heat to about 400 ° C.

Instead of the water vapor is the carbon monoxide and hydrogen-containing from the PSA plant 13 a partial amount or the total amount of the excess gas from the gas scrubber 7 with an elevated temperature, thus also with a higher water vapor content, fed. A higher water vapor content of the excess gas is achieved by setting a higher feed water temperature for gas scrubbing 7 reached. This eliminates the need for a steam generating plant and the compression of the excess gas, since its pressure is sufficient for use in the DRI system. In addition, the PSA system 13 smaller and cheaper and the power consumption for the compression of the gas for the PSA plant lower. The excess gas may be supplied to the product gas from the PSA plant because its carbon dioxide content is relatively low and need not be excreted in the PSA plant. The limitation of the amount of excess gas that is supplied to the carbon monoxide and hydrogen-containing product gas, however, depends on the hydrogen sulfide of the mixed gas or sulfur content of the produced sponge iron.

To use the waste heat of the top gas from the DRI reduction shaft 16 is a top gas heat exchanger in the top gas line 31 built-in. In it, in addition to the product gas from the PSA 13 that too, in a gas wash 7 washed excess gas, via pipe 30 supplied to better exploit the waste heat of the top gas and less fuel gas for the further heating of the product gas in the heat exchanger 14 to consume.

The product gas is turned into a gas heater 15 by oxygen addition and partial combustion of hydrogen and carbon monoxide present in the gas, heated to the required temperature, in the DRI reduction device 16 introduced and used for the production of sponge iron, at the lower end of the reduction device 16 is discharged.

Claims (13)

Method for operating a reduction device and a melt gasifier Corex or Finex plant for the production of sponge iron and pig iron, in which coke oven gas is treated and used as a reducing gas in the operation of the Corex or Finex plant. A method according to claim 1, characterized in that the excess heat / waste heat of the gasifier gas, reducing gas, top gas and / or excess gas of the Corex or Finex plant is used to heat the coke oven gas for the production of reducing gas. Method according to one of the preceding claims, characterized in that the Kokereigas is mixed with gasification gas and fed as reducing gas of the reduction device. Method according to one of the preceding claims, characterized in that Kokereigas is heated to such a high temperature that methane, higher hydrocarbons and toxic components in the Corex or Finex plant, in particular in the reduction device, by carbon dioxide and water vapor, under catalytic action of the freshly reduced sponge iron, be decomposed to carbon monoxide and hydrogen. Method according to one of the preceding claims, characterized in that the nitrogen used for conveying, cooling and rinsing purposes is replaced by cold Kokereigas. Method according to one of the preceding claims, characterized in that the reducing gas generated from Kokereigas is used partly in the Corex or Finex plant and for the most part in a second reduction device, in particular a DRI reduction device, for the production of sponge iron. Method according to one of the preceding claims, characterized in that the gas scrubbing is driven by excess gas with increased flow water temperature. A method according to claim 6, characterized in that the waste heat of the top gas from the DRI reduction device for heating carbon monoxide and hydrogen-containing gas from a PSA plant and the excess gas is used from a gas scrubbing. A method according to claim 6 or 8, characterized in that the amount of Kokereigases which is supplied to the gasification gas and various aggregates of the Corex or Finex plant, and the temperature of the reducing gas for the reduction devices depending on the methane content of the top gas from the DRI Reduction device is set. Plant for carrying out the process according to one of the preceding claims, which is designed as a Corex or Finex plant and a melt gasifier ( 1 ) and one above the melt gasifier or next to the melt gasifier ( 1 ) arranged reduction device ( 4 ), characterized in that it has facilities for the preparation and use of Kokereigas as reducing gas in the operation of the Corex or Finex plant. Plant according to claim 10, characterized in that the Corex or Finex plant is provided with a second reduction device, in particular a DRI reduction device, for the production of sponge iron. Plant according to claim 10 or 11, characterized in that it comprises means for heating the coke oven gas by the excess heat / waste heat of the gasifier gas, reducing gas, top gas and / or excess gas of the Corex or Finex plant. Installation according to claim 10 to 12, characterized in that it comprises means for mixing the Kokereigases with gasification gas.

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