AU4454699A

AU4454699A - Process for producing liquid pig iron

Info

Publication number: AU4454699A
Application number: AU44546/99A
Authority: AU
Inventors: Kurt Wieder; Johann Wurm; Parviz Dr Zahedi
Original assignee: Voest Alpine Industrienlagenbau GmbH
Current assignee: Primetals Technologies Austria GmbH
Priority date: 1998-09-09
Filing date: 1999-08-17
Publication date: 2000-03-16
Also published as: AT407055B; ATA152498A; DE19938026A1

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s):

VOEST-ALPINE

A.R.B.N. 052 INDUSTRIEANLAGENBAU GmbH 122 791 Invention Title: PROCESS FOR PRODUCING LIQUID PIG IRON.

The following statement is a full description of this invention, including the best method of performing it known to me/us: 14 Process for producing liquid pig iron The invention relates to a process for producing liquid pig iron or primary steel products from iron-oxide-containing charge materials and additions if required, preferably in each case in the form of pieces and/or pellets, the iron-oxide-containing charge materials being reduced directly to iron sponge in the reducing zone of a reducing reactor, and the iron sponge being smelted in the fusion gasifier zone of a fusion gasifier supplied with carbon-containing material, which is at least partially formed from screenings and coal dust, and oxygen-containing gas, a CO- and H2-containing generator gas being generated, which gas, after dedusting, is introduced into the reducing zone as a reducing gas, partially converted there, drawn off as top gas from the reducing zone, cleaned and supplied to a consumer as export gas, and to a plant for carrying out the process.

A problem of processes of the type mentioned above is that when finely particulate carbon-containing material, such as screenings and coal dust, is fed into a fusion gasifier, the finely particulate S 25 carbon-containing material is immediately discharged from the fusion gasifier again owing to the gas velocities prevailing therein. The same equally applies to finely particulate ore. In order to prevent this, it has been proposed, for example, in AT-B-401 777 to 30 introduce carbon carriers together with fine ore and/or ore dust into the fusion gasifier, specifically into the lower part thereof, by means of pulverized-fuel e burners. This results in sub-stoichiometric combustion of the carbon carriers. A drawback of this is that the carbon carriers are unable to make any contribution to building up a bed of solid carbon carriers in the fusion gasifier.

It is also known to supply the upper part of a fusion gasifier with finely particulate coal, the 2 finely particulate coal being converted into coke, the coke being discharged with the reducing gas and being separated from the reducing gas and then, together with finely particulate material, being fed to the fusion gasifier by means of a burner. In this case, however, there is again no contribution to building up a bed formed of carbon-containing material.

Such a bed is usually formed by means of lumpy coal. Due to the evolution of the coal market, which is largely determined by the requirements of coal-fired power plant operators and smelting plants, it may be preferred to supply screenings for coal-dust burners, coking plants and other metallurgical processes. Grate firings which were previously customary and required the use of lumpy coal are now of only subordinate importance on the coal consumer market. This has led to the fine fraction of commercially available coals increasing considerably, now representing a level of from 50 to In a process mentioned above, it is necessary to use coals which lie within a defined size range, usually 5 to 40 mm. The majority of coals available on *the market cannot be used, since they are too small.

Moreover, the coals used must have a suitable 25 composition with regard to their levels of volatile and non-volatile (Cfi) components.

Low-quality coals, i.e. those with a high level of volatile components, have hitherto been regarded as unsuitable since the temperature in the upper part of 30 the fusion gasifier is insufficient, or else a higher S. temperature than hitherto is required, in order to decompose the hydrocarbons which are formed when the coals are introduced into the fusion gasifier. If coals with a high carbonization level are used, i.e. with a low level of volatile components, there is no guarantee that the ore-reduction process will be supplied with sufficient reducing gas which is formed in the fusion gasifier.

-3 The invention is based on the object of circumventing the difficulties involved in the provision of lumpy coal and also making it possible to use coals with a hitherto impermissible level of volatile components for a process described above. At the same time, the economics are to be improved compared to the process used hitherto, as a result of savings on the consumption of coal and oxygen.

This object is achieved by the fact that screenings and coal dust provided for use, which each contain a high level of volatile components, are subjected to partial carbonizing, and are then hot-briquetted, tar components of the coal being used as binder, and the briquettes formed being used in a heated state in the fusion gasifier.

AT-B-376 243 has disclosed a process in which the coal used is hard coal which is coked in a hearth furnace before it is introduced into the fusion gasifier, and the coked coal, with its sensible heat, is introduced into the fusion gasifier. However, this leads to the use of a carbonized coal with an insufficient level of volatile components, so that the supply of reducing gas to an ore-reduction process is insufficient. AT-B-376 243 furthermore proposes 25 briquetting the fines fraction produced during coking and using these briquettes in the fusion gasifier.

Owing to the temperatures which prevail during coking (600 to 10000C), however, the coke then contains no tar components, or scarcely any tar components, so that 30 this coke cannot be briquetted without using a binder.

Furthermore, there are no reductants obtained from tar components available for the reducing shaft. According to the invention, this problem is circumvented by the fact that the carbonization of the screenings only takes place to a partial extent, so that the partially carbonized coal still contains sufficient volatile components for use in the fusion gasifier.

The process according to the invention has, for the first time, enabled low-quality screenings with a 4high level of volatile components to be used for a combined reduction and smelting reduction process, in that they are more intensively carbonized, and furthermore, by employing the briquetting in the hot state, it is also possible to use screenings in the process, with the result that it is possible to use coals which are altogether more available and less expensive.

Since the coal briquettes formed are used in the fusion gasifier with their calorific content from the briquetting being exploited, a positive contribution is made to the energy balance of the overall process, and the demand for coal and oxygencontaining gas is reduced. However, slight cooling of the briquettes may take place, so that they exhibit sufficient mechanical stability.

Additional savings on coal and oxygencontaining gas (usually air or industrial oxygen) result from the fact that a lower temperature is required in the top part of the fusion gasifier for decomposition of volatile components, since such components are released to a lesser extent. This temperature reduction is also achieved by the reduced amounts of coal and oxygen used.

25 A further effect of the temperature reduction consists in the fact that the oxidation level of the reducing gas is increased, therefore, the levels of CO 2 and H 2 0 increase. The result is a considerably improved energy utilization, associated with a saving 30 on coal and oxygen.

Due to the use of coal briquettes, the size of the coal used in the fusion gasifier is substantially uniform. This leads to an improved gas distribution in the bed formed in the fusion gasifier and therefore, in turn, to a reduced consumption of coal and oxygen, and to an overall stabilization of product quality.

According to a preferred embodiment of the process according to the invention, the briquettes formed are subjected to subsidiary carbonization prior to being used in the fusion gasifier.

Particularly when using low-quality coals containing a high level of volatile constituents, it is advantageous for the level of tar components in the briquettes to be reduced still further.

According to a preferred embodiment, screenings and coal dust are separated out of the carboncontaining material used and are then subjected to the partial carbonization.

According to a preferred embodiment, lumpy carbon-containing material which is formed when separating off the screenings and the coal dust is subjected to the subsidiary carbonization and is then used in the fusion gasifier and/or used directly, i.e.

without any carbonization, in the fusion gasifier.

By selecting and controlling the mass flow rates of briquettes and non-briquetted, lumpy carboncontaining material, which are each supplied to the subsidiary carbonization and/or directly to the fusion gasifier, it is possible to control or influence the amount of reducing gas formed in the fusion gasifier, and the quality, i.e. reduction potential, of this gas.

Preferably, coal dust and screenings with a OOen 25 particle size of less than or equal to 8 mm are ee separated out of the carbon-containing material.

According to one embodiment of the process according to the invention, the partial carbonization of the screenings and of the coal dust are [sic] 30 carried out at a temperature of less than 600 0

C,

J..preferably at a temperature of between 2500C and 3800C.

In this temperature range, it is ensured that the coal is not completely coked, i.e. that it is impossible for substantially all the volatile constituents and tar components to be driven out, but rather that only the fraction of volatile components which exceeds the level permitted for operation of a fusion gasifier is removed from the coal. In addition, the consistency of the coal is altered, in that it is 6 partially plasticized and is thus more amenable to briquetting. The tar components which remain in the coal soften, so that they are able to serve as a binder during the subsequent briquetting operation.

According to a preferred embodiment, the briquetting of the partially carbonized screenings and of the partially carbonized coal dust is carried out at a temperature of less than 600 0 C, preferably at a temperature of between 240 0 C and 3800C.

Particularly preferably, the briquetting takes place at the temperature which results from the partial carbonization.

Expediently, therefore, the calorific content of the screenings and of the coal dust after partial carbonization is employed for the briquetting operation. There is no need to use any additional thermal energy for briquetting.

Expediently, tar components are separated out of the carbonization gas which is formed during the partial carbonization and are mixed with the partially carbonized screenings and the partially carbonized coal dust.

By using the tar components which have been separated out of the carbonization gas as a binder, it is possible to dispense with an additional binder altogether during briquetting.

The energy requirements of the partial carbonization is preferably at least partly covered by the process gas produced during the partial carbonization. Depending on the type of coal used, the gas formed during the partial carbonization contains up to 30 to 70% CO, H 2 and hydrocarbons, and is consequently combustible and can advantageously be used for the generation of energy.

35 Expediently, in this case, the gas formed during the partial carbonization is at least partly burnt and the hot combustion gases are fed to the partial carbonization.

Alternatively, oxygen and/or air are supplied to the partial carbonization, and the partial combustion of the carbonization gas is carried out together with the partial carbonization.

Advantageously, the partial carbonization is carried out using a fluidized-bed process, for example, in a fluidized-bed reactor or a fluidized-bed dryer.

Alternatively, the partial carbonization is carried out using a spouted bed process, in which case the selection of the type of process is essentially determined by the particle sizes of the screenings or coal dust used.

The subsidiary carbonization of the lumpy carbon-containing material and/or the briquettes is expediently carried out using a fixed-bed process at temperatures of less than 600 0 C, preferably at temperatures of between 450 0 C and 550 0

C.

The temperature of the subsidiary carbonizing is at any rate selected to be such that no coking as yet takes place, but rather further volatile components are simply expelled from the lumpy carbon-containing material or the briquettes.

".According to a variant embodiment of the 25 process according to the invention, a part stream of the export gas is compressed, subjected to CO 2 removal, heated and fed to the reducing gas stream.

As a result of using the partially carbonized coal, and due to the resultant savings on coal, it may arise (in particular, depending on the residual level of volatile components after the subsidiary carbonization) that the amount of reducing gas produced in the fusion gasifier is insufficient for operation of the reduction reactor. Since the export gas still 35 contains approximately 50% reductants, the export gas is supplied to a CO 2 scrubber after compression. The reducing-gas temperature of approximately 8000C which is required is set by heating, for example in two stages, initially by means of the indirect supply of 8 heat and then by means of the direct supply of heat, and the export-gas stream which has been treated in this way is fed to the reducing-gas stream and consequently to the reduction reactor.

According to a further advantageous feature of the process according to the invention, a part stream of the reducing gas is branched off as surplus gas, subjected to gas cleaning, and a part stream of the cleaned surplus gas is compressed and fed as cooling gas to the generator gas, and a second part stream of the cleaned surplus gas is fed to the export gas.

The measures of branching off and returning part streams of the surplus gas are used to control the process pressure of the reduction and the smelting reduction process.

The invention also relates to a plant for producing liquid pig iron and/or primary steel products from charge materials formed by iron-oxide-containing substances, and additions if required, preferably in each case in the form of pieces and/or pellets, having a reduction reactor for iron-oxide-containing substances, a fusion gasifier, a supply line connecting the fusion gasifier to the reduction reactor for a reducing gas formed in the fusion gasifier, the reducing-gas supply line being provided with a gas-cleaning device, having a feed line connecting the reduction reactor to the fusion gasifier for the reduction product formed in the reduction reactor, having a top-gas removal line, leading from the reduction reactor and provided with a scrubber, having a feed line for carbon-containing material, having supply lines for oxygen-containing gases opening into the fusion gasifier, and a run-off for liquid pig iron and liquid slag, provided on the fusion gasifier.

35 Such a plant is characterized in that a carbonization reactor is provided for partial carbonizing of screenings and coal dust, and a hot-briquetting device for briquetting partially carbonized screenings and partially carbonized coal -9 dust is connected downstream of the carbonization reactor, the hot-briquetting device being connected to the fusion gasifier via the feed line.

According to a preferred embodiment, the hot-briquetting device is connected to a subsidiary carbonization reactor by means of a further feed line, the subsidiary carbonization reactor in turn being connected to the fusion gasifier.

According to another preferred embodiment, a separating device for separating screenings and coal dust out of the carbon-containing starting material used is provided.

According to another preferred embodiment, the separating device is connected to the fusion gasifier via a supply line for lumpy carbon-containing material.

A further supply line provides a connection between the separating device and the subsidiary carbonization reactor.

Expediently, a gas line for combustible carbonization gas formed in the carbonization reactor leads away from the carbonization reactor, which gas line opens into a heater device which is connected to the carbonization reactor.

Expediently, a supply line for an oxygencontaining gas also opens into this heater device, and furthermore the heater device may be connected to an additional supply line for a combustible gas, which is used when the amount of carbonization gas produced in the carbonization reactor is insufficient to cover the energy requirements of the carbonization reactor.

According to an advantageous feature of the plant according to the invention, a mixing and homogenization device is connected downstream of the carbonization reactor.

35 In this mixing and homogenization device, partially carbonized screenings and/or partially carbonized coal dust, as well as untreated screenings or coal dust,- if appropriate, are intimately mixed.

Carbon-containing starting material can likewise be 10 supplied directly to the mixing and homogenization device if this material is suitable both in terms of its particle sizes and in terms of the tar content.

Furthermore, it is possible to supply the mixing and homogenization device with tar components which have been separated out of the carbonization gas.

According to another advantageous feature, a tar separator for separating tar components out of the carbonization gas is arranged in the gas line, it being possible to supply tar components which have been separated out to the mixing and homogenization device.

As a result, tar components which have been expelled from the coal together with the carbonization gas can advantageously be used, as it were, as an "inprocess" binder for the briquetting operation.

The carbonization reactor can be designed to equally good effect as a fluidized-bed reactor, as a spouted-bed reactor or as a fluidized-bed dryer, while the subsidiary carbonization reactor is preferably designed as a fixed-bed reactor.

Expediently, a surplus-gas line containing a gas scrubber branches off from the reducing-gas supply line downstream of the gas-cleaning device, which surplus-gas line combines with the top-gas removal line to form an export-gas line.

A preferred configuration of the plant according to the invention is characterized in that the export-gas line is connected to the reducing-gas line via a branch line. Via this branch line, export gas is fed back into the reducing-gas stream and therefore *into the reduction reactor.

Expediently, to this end, a compressor, a C0 2 removal device, for example an alternating pressure adsorption plant, and a heater device are arranged in S 35 succession in the branch line.

In order to be able to use the export gas again as a reducing gas, it must initially be compressed to a pressure which is suitable for the reduction reactor,

CO

2 has to be largely removed, and then the gas has to 11 be heated to the reducing-gas temperature (approximately 800 0 To this end, the heater device may, for example, be designed as a two-stage heater device, with a first heat exchanger for preheating as the first stage, and with a further heating stage, the heat energy for which is obtained from a partial combustion of export gas.

The invention is explained in more detail below with reference to the drawing, Fig. 1, which shows a preferred embodiment of the invention.

A reduction reactor 1 designed as a shaft furnace, i.e. its reducing zone 2, is charged from above, via a charging device 3, with lumpy iron-oxidecontaining charge materials, such as ore 4, if required with uncalcined additions 5. The reduction reactor 1 is in connection with a fusion gasifier 6, in which a reducing gas is generated from carbon carriers, which are supplied via a feed line 7, and oxygen-containing gas, which is supplied via one or more gas lines 8, is supplied via a reducing-gas supply line 9, 10 to the reduction reactor 1 and flows through the latter in counterflow with respect to the charge materials 4, In the reducing-gas supply line 9, there is provided a gas-cleaning device 11, for example a hot-gas cyclone.

Dust which is separated out in this gas-cleaning device S11 is fed back to the fusion gasifier 6 by means of pulverized-fuel burners 12, if appropriate with the aid of a carrier gas, usually nitrogen.

Via supply lines 13, the fusion gasifier 6 is fed with the reduction product produced in the reduction reactor 1, i.e. completely or partially reduced iron sponge. The reduction reactor 1 is furthermore provided with a top-gas removal line 14, by means of which the top gas, which is a partially 35 reacted reducing gas, is drawn out of the reduction reactor 1. A gas scrubber 15, by means of which the top gas is cooled and entrained dust is separated out, is arranged in the top-gas removal line 14.

12 A surplus-gas line 16, in which a gas scrubber 17 likewise effects cooling and dust separation, branches off from the reducing-gas supply line Downstream of the gas scrubber 17, a cooling-gas line 18 branches off from the surplus-gas line 16, through which cooling-gas line cleaned and cooled gas is fed to the reducing gas which has been drawn out of the fusion gasifier 6. Surplus-gas line 16 and top-gas removal line 14 combine to form an export-gas line 19, through which export gas is made available to a consumer for example for power generation.

Liquid pig iron 21 and liquid slag 22 collect in the bottom part of the fusion gasifier 6 and are run off via a run-off 23.

Firstly, in a separating device 25, for example a screen, the lumpy material is separated off from carbon-containing starting material 24 which is provided for use in the fusion gasifier 6 and, if appropriate, has been pre-dried, and remaining screenings or coal dust is/are supplied to a carbonization reactor 27 which is connected downstream of the separation device 25 and in which the screenings or coal dust are partially carbonized at temperatures of from 250 to 380 0 C. A proportion of the volatile components contained in the coal remain in the coal as o tar components, while the other proportion is expelled with the carbonization gas which is formed during the carbonization.

The combustible carbonization gas which is formed during the carbonization of the coal in the carbonization reactor 27 is fed through a gas line 29 to a tar separator 38 and then to a heater device in which it is burnt. Via a further gas line 31, the heater device 30 may, if appropriate, be fed with 35 additional combustible gas, should the carbonization gas produced in the carbonization reactor 20 be insufficient to cover the energy requirements.

As an alternative to a heater device 30, the partial combustion of the carbonization gas may be 13 carried out in the carbonization reactor 27 itself, with the simultaneous supply of an oxygen-containing gas.

Via a removal line 39, some of the carbonization gas is removed, in order to prevent it from being enriched with non-combustible constituents.

Hot, partially carbonized screenings and coal dust from the carbonization reactor 27 are intimately mixed in a mixing and homogenization device 37, for example an intensive mixer, with tar components which have been separated out in the tar separator 38 and, if appropriate, with untreated screenings or coal dust and/or carbon-containing starting material 24 (in each case indicated by dashed lines).

In addition, the mixing and homogenization device 37 may be supplied with inert material, such as scale, oxide dust, coke dust, etc., and this material may be mixed (not shown) with the partially carbonized screenings and coal dust.

The product from the mixing and homogenization device 37 is briquetted while still hot, in the hotbriquetting device 28. There is no need for additional o thermal energy for this operation. The briquettes which are produced in the hot-briquetting device are introduced into the fusion gasifier 6 via the feed line 7, utilizing their sensible heat, i.e. their temperature.

If appropriate, the briquettes formed may be slightly cooled, for example by 500C, in order to solidify the tar components used as binder and thus to .'".increase the mechanical stability of the briquettes.

Such cooling may be carried out on a cooling device (not shown in the drawing) for example a cooling belt and/or a bunker.

35 As an alternative to being used immediately in the fusion gasifier 6, the briquettes may be supplied, via a further feed line 7a, to a subsidiary carbonization reactor 36, where, possibly together with lumpy carbon-containing material from the separating 14 device 25, they are carbonized further at temperatures of less than 6000C.

The gas which is formed during the subsidiary carbonization 36 can be used to heat the subsidiary carbonization reactor 36 and/or the partial carbonization reactor 27, and/or may be introduced into the reducing-gas supply line 9 and/or the top-gas removal line 14. These possible applications are not illustrated in the drawing.

Lumpy carbon-containing material from the separation device 25 may also, depending on its tar content, be supplied directly, via a supply line 26a, to the feed line 7 and therefore to the fusion gasifier.

The reducing-gas supply line 10 is connected to the export-gas line 19 via a branch line 32. A compressor 33, a C0 2 -removal device 34, for example an alternating pressure adsorption plant, and a heater device 35 are arranged in succession in the branch line 32. Via the branch line 32, a part stream of the export gas is compressed, C02 is removed, the part stream is heated to the reducing-gas temperature and is introduced into the reducing-gas stream 10 which is intended for the reduction reactor i.

25 The invention is not limited to the exemplary embodiment illustrated in Fig. i, but rather comprises all means which are known to the person skilled in the art that can be employed in order to implement the invention.

For the purposes of this specification it will be clearly ~understood that the word "comprising means "including but not limited to", and that the word "comprises" has a corresponding meaning.

Claims

1. Process for producing liquid pig iron or primary steel products from iron-oxide-containing charge materials and additions if required, preferably in each case in the form of pieces and/or pellets, the iron-oxide-containing charge materials being reduced directly to iron sponge in the reducing zone of a reducing reactor, and the iron sponge being smelted in the fusion gasifier zone of a fusion gasifier supplied with carbon-containing material, which is at least partially formed from screenings and coal dust, and oxygen-containing gas, a CO- and H 2 -containing generator gas being generated, which gas, after dedusting, is introduced into the reducing zone as a reducing gas, partially converted there, drawn off as top gas from the reducing zone, cleaned and supplied to a consumer as export gas, characterized in that screenings and coal dust provided for use, which each contain a high level of volatile components, are subjected to partial carbonizing, and are then hot-briquetted, tar components of the coal being used as binder, and the briquettes formed being used in a heated state in the fusion gasifier. 25 2. Process according to Claim 1, characterized in that the briquettes formed are subjected to subsidiary carbonization prior to being used in the fusion gasifier.

3. Process according to one of Claims 1 or 2, characterized in that screenings and coal dust are separated out of a carbon-containing starting material **which is intended to be used and are then subjected to the partial carbonization.

4. Process according to Claim 3, characterized in 35 that lumpy carbon-containing material which is formed when separating off the screenings and the coal dust is subjected to the subsidiary carbonization and is then used in the fusion gasifier and/or used directly in the fusion gasifier. 16 Process according to one of Claims 3 or 4, characterized in that coal dust and screenings with a particle size of less than or equal to 8 mm are separated out of the carbon-containing starting material.

6. Process according to one of Claims 1 to characterized in that the partial carbonization of the screenings and of the coal dust is carried out at a temperature of less than 6000C, preferably at a temperature of between 250 0 C and 3800C.

7. Process according to one of Claims 1 to 6, characterized in that the briquetting of the partially carbonized screenings and of the partially carbonized coal dust is carried out at a temperature of less than 6000C, preferably at a temperature of between 2400C and 380 0 C.

8. Process according to Claim 7, characterized in that the briquetting takes place at the temperature which results from the partial carbonization.

9. Process according to one of Claims 1 to 8, characterized in that tar components are separated out of the carbonization gas which is formed during the partial carbonization and are mixed with the partially carbonized screenings and the partially carbonized coal dust. Process as claimed in one of Claims 1 to 9, characterized in that the energy requirement for the partial carbonization is at least partly covered by a means of carbonization gas which is formed during the partial carbonization.

11. Process according to Claim 10, characterized in e•that carbonization gas which is formed during the partial carbonization is at least partly burnt, and the hot combustion gases are fed to the partial S 35 carbonization.

12. Process according to Claim 10, characterized in that oxygen-containing gas is fed to the partial carbonization, and the combustion of the carbonization gas takes place together with the partial gasification. 17

13. Process according to one of Claims 1 to 12, characterized in that the partial carbonization is carried out using a fluidized-bed process.

14. Process according to one of Claims 1 to 13, characterized in that the partial carbonization is carried out using a spouted bed process. Process according to one of Claims 2 to 14, characterized in that the subsidiary carbonization of the lumpy carbon-containing material and/or of the briquettes is carried out using a fixed-bed process.

16. Process according to Claim 15, characterized in that the subsidiary carbonization is carried out at a temperature of less than 6000C, preferably at a temperature of between 4500C and 5500C.

17. Process according to one of Claims 1 to 16, characterized in that a part stream of the export gas is compressed, subjected to CO 2 removal, heated and fed to the reducing gas stream.

18. Process according to one of Claims 1 to 17, characterized in that a part stream of the reducing gas is branched off as surplus gas, subjected to gas cleaning, and a part stream of the cleaned surplus gas is compressed and fed as cooling gas to the generator gas, and a second part stream of the cleaned surplus 25 gas is fed to the export gas.

19. Plant for producing liquid pig iron and/or primary steel products from charge materials formed by iron-oxide-containing substances and additions if required, preferably in each case in the form of pieces and/or pellets, having a reduction reactor (1) for iron-oxide-containing substances a fusion S. gasifier a supply line 10) connecting the fusion gasifier to the reduction reactor for a reducing gas formed in the fusion gasifier the 35 supply line being provided with a gas-cleaning device having a feed line (13) connecting the reduction reactor to the fusion gasifier for the reduction product formed in the reduction reactor having a top-gas removal line leading from -18 the reduction reactor and provided with a scrubber having a feed line for carbon-containing material, having supply lines for oxygen-containing gases opening into the fusion gasifier and a run-off (23) for liquid pig iron (21) and liquid slag provided on the fusion gasifier characterized in that a carbonization reactor (27) is provided for partial carbonizing of screenings and coal dust, and a hot-briquetting device (28) for briquetting partially carbonized screenings and partially carbonized coal dust is connected downstream of the carbonization reactor, the hot-briquetting device (28) being connected to the fusion gasifier via the feed line

20. Plant according to Claim 19, characterized in that the hot-briquetting device (28) is connected to a subsidiary carbonization reactor (36) by means of a further feed line the subsidiary carbonization reactor (36) in turn being connected to the fusion gasifier (6)

21. Plant according to one of Claims 19 or characterized in that a separating device (25) for Sseparating screenings and coal dust out of the Scarbon-containing starting material (24) used is 25 provided. S22. Plant according to Claim 21, characterized in that the separating device (25) is connected to the fusion gasifier via a supply line (26a) for lumpy S" carbon-containing material.

23. Plant according to one of Claims 21 or 22, characterized in that the separating device (25) is a. *.connected to the subsidiary carbonization reactor (36) via a supply line (26) for lumpy carbon-containing material.

24. Plant according to one of Claims 19 to 23, a characterized in that a gas line (29) for combustible carbonization gas formed in the carbonization reactor (27) leads away from the carbonization reactor (27), 19 which gas line opens into a heater device (30) which is connected to the carbonization reactor (27). Plant according to one of Claims 19 to 23, characterized in that a gas line (29) for combustible carbonization gas formed in the carbonization reactor (27) leads away from the carbonization reactor (27), oxygen-containing gas in turn being fed to the carbonization reactor (27).

26. Plant according to one of Claims 19 to characterized in that a mixing and homogenization device (37) is connected downstream of the carbonization reactor (27).

27. Plant according to Claim 26, characterized in that a tar separator (38) for separating tar components out of the carbonization gas is arranged in the gas line it being possible to supply tar components which have been separated out to the mixing and homogenization device (37).

28. Plant according to one of Claims 19 to 27, characterized in that the carbonization reactor (27) is designed as a fluidized-bed reactor. S29. Plant according to one of Claims 19 to 27, characterized in that the carbonization reactor (27) is designed as a fluidized-bed dryer.

30. Plant according to one of Claims 19 to 37 [sic], characterized in that the carbonization reactor (27) is designed as a spouted bed reactor. S31. Plant according to one of Claims 20 to 29, characterized in that the subsidiary carbonization reactor (36) is designed as a fixed-bed reactor.

32. Plant according to one of Claims 19 to We Scharacterized in that a surplus-gas line (16) containing a gas scrubber (17) branches off from the reducing-gas supply line downstream of the 35 gas-cleaning device which surplus-gas line combines with the top-gas removal line (14) to form an export-gas line (19). 20

33. Plant according to Claim 31, characterized in that the export-gas line (19) is connected to the reducing-gas line (10) via a branch line (32).

34. Plant according to Claim 32, characterized in that a compressor a C0 2 -removal device (34) and a heater device (35) are arranged in succession in the branch line (32). Dated this 17th day of August 1999 VOEST-ALPINE INDUSTRIEANLAGENBAU GMBH By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia e *t a* Sa *eea *mo•