AU681836B2 - Process for producing molten pig iron or molten steel pre-products - Google Patents
Process for producing molten pig iron or molten steel pre-products Download PDFInfo
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- AU681836B2 AU681836B2 AU70556/96A AU7055696A AU681836B2 AU 681836 B2 AU681836 B2 AU 681836B2 AU 70556/96 A AU70556/96 A AU 70556/96A AU 7055696 A AU7055696 A AU 7055696A AU 681836 B2 AU681836 B2 AU 681836B2
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- 238000000034 method Methods 0.000 title claims description 29
- 230000008569 process Effects 0.000 title claims description 23
- 229910000805 Pig iron Inorganic materials 0.000 title claims description 20
- 229910000831 Steel Inorganic materials 0.000 title claims description 12
- 239000010959 steel Substances 0.000 title claims description 10
- 239000007789 gas Substances 0.000 claims description 144
- 230000009467 reduction Effects 0.000 claims description 79
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 59
- 239000000126 substance Substances 0.000 claims description 51
- 229910052742 iron Inorganic materials 0.000 claims description 28
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 16
- 229910052760 oxygen Inorganic materials 0.000 claims description 16
- 239000001301 oxygen Substances 0.000 claims description 16
- 229910052799 carbon Inorganic materials 0.000 claims description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 9
- 230000005484 gravity Effects 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 8
- 239000007788 liquid Substances 0.000 claims description 8
- 238000002844 melting Methods 0.000 claims description 8
- 230000008018 melting Effects 0.000 claims description 8
- 239000000969 carrier Substances 0.000 claims description 7
- 229910052739 hydrogen Inorganic materials 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 5
- 238000005201 scrubbing Methods 0.000 claims description 5
- 238000001465 metallisation Methods 0.000 claims description 4
- 230000007704 transition Effects 0.000 claims description 4
- 238000007599 discharging Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 claims description 2
- 241000196324 Embryophyta Species 0.000 description 11
- 238000004519 manufacturing process Methods 0.000 description 10
- 239000007787 solid Substances 0.000 description 8
- 238000004458 analytical method Methods 0.000 description 7
- 230000004907 flux Effects 0.000 description 6
- 239000000571 coke Substances 0.000 description 5
- 239000003245 coal Substances 0.000 description 4
- 241001232253 Xanthisma spinulosum Species 0.000 description 3
- 239000000428 dust Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 235000002918 Fraxinus excelsior Nutrition 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- 101150093411 ZNF143 gene Proteins 0.000 description 1
- 239000002956 ash Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011236 particulate material Substances 0.000 description 1
- JTJMJGYZQZDUJJ-UHFFFAOYSA-N phencyclidine Chemical class C1CCCCN1C1(C=2C=CC=CC=2)CCCCC1 JTJMJGYZQZDUJJ-UHFFFAOYSA-N 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/10—Reduction of greenhouse gas [GHG] emissions
- Y02P10/122—Reduction of greenhouse gas [GHG] emissions by capturing or storing CO2
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/10—Reduction of greenhouse gas [GHG] emissions
- Y02P10/134—Reduction of greenhouse gas [GHG] emissions by avoiding CO2, e.g. using hydrogen
Landscapes
- Manufacture Of Iron (AREA)
- Manufacture And Refinement Of Metals (AREA)
Description
AUSTRALIA
Patents Act 1990 COMPLETE SPECIFICATION STANDARPD PATENT Applicants: VOEST-ALPINE INDUSTRIEANLAGENBAU GmibH A.R.B.N. 052 122 791 RESEARCH INSTITUTE OF INDUSTRIAL SCIENCE TECHNOLOGY, INCORPORATED FOUNDATION POHANG IRON STEEL CO., LTD.
a a a Invention Title: PROCESS FOR PRODUCING MOLTEN PIG IRON OR MOLTEN STEEL PRE-PRODUCTS The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 The invention relates to a process for producing molten pig iron or molten steel pre-products from charging substances formed of iron ores and fluxes and at least partially comprising fines, wherein the charging substances are directly reduced to sponge iron in at least one reduction zone by the whirl layer method, the sponge iron is melted in a melting-gasifying zone under supply of carbon carriers and oxygen-containing gas, and a CO and H 2 -containing reducing gas is produced, which is injected into the reduction zone, is reacted there, is withdrawn as an export gas and is supplied to a consumer, as well as a plant for carrying out the process.
The "whirl layer method" is more commonly known in Australia as the "fluidised bed method", and consequently a whirl-layer bed is better known in Australia as a fluidised bed. Whilst the claims refer to a fluidised bed and the description of the invention below refers to a whirl-layer bed, it is to be understood that these two phrases refer to the same feature.
20 This application is a divisional application from Australian patent application 49134/93, which is incorporated herein by reference.
According to the present invention there is provided a process for producing molten pig iron or liquid steel preproducts and for producing hot-briquetted iron, which process comprises: preheating a first charging substance which comprises iron ore in a fluidised bed of a first preheating zone so as to obtain a preheated charging substance, stalfuan/keep149134.93.UIVISIONAL 30,10.96 3 (ii) substantially reducing said preheated charging substance to form a reduced charging substance in a fluidised bed of a first reduction zone, (iii) melting the reduced charging substance of step (ii) in a melting gasifying zone in the presence of carbon carriers and an oxygen-containing gas to produce a CO and H 2 -containing reducing gas, (iv) directing the reducing gas of step (iii) into the first reduction zone of step (ii) and reacting the reducing gas with the preheated charging substance to produce a top gas, directing the top gas of step (iv) to the first preheating zone for preheating the first charging substance and withdrawing the gas as an export gas, (vi) removing CO 2 from the export gas and heating the export gas by directing the export gas through a CO scrubber and a preheating means, (vii) preheating a second charging substance which comprises iron ore in a second p:ceheating zone so as to obtain a preheated charging substance, (viii) substantially reducing the preheated charging substance of step (vii) with the CO, scrubbed and preheated export gas of step (vi) in a fluidised bed of a second reduction zone to produce a reduced product, and (ix) compressing and briquetting the reduced product of step (vii).
stalftuan/ke49134,9DIVISIONAL 30.10,96 4 Preferably, the preheating step (vi) comprises partially combusting the export gas to elevate the gas temperature.
Preferably, the process comprises mixing the export gas with a portion of the top gas of step (iv) before removing
CO
2 from the export gas in CO 2 scrubbing step (vi).
Preferably, step (vi) comprises CO, scrubbing the export gas and thereafter heating the export gas to approximately 8500C.
Preferably, the process comprises injecting the reduced product of step (viii) into a charging bunker for subsequent compressing and briquetting by aid of N 2 injectors.
Preferably, the process comprises discharging the reduced product of step (viii) from a lower region of the second reduction zone into a charging bunker by gravity discharge.
Preferably, the degree of metallisation of the reduced product of step (viii) is approximately 92%.
a Preferably, the reduced product of step (viii) has a temperature of at least 750 0 C when it is subjected to 20 briquetting.
According to another aspect of the present invention there is provided a plant for producing molten pig iron or liquid steel pre-products and for producing hot-briquetted iron, which plants comprises: a first fluidised bed preheating reactor for preheating a first charging substance which comprises iron ore, siaf/uanlkeepl49l34.93.DIVISIONAL 30.10.96 5 (ii) (iii) (iv) (v) (vi) (vii) a first fluidised bed reduction reactor downstream of the first preheating reactor for reducing the preheated charging substance to produce a reduced charging substance, a melter-gasifier for melting the reduced charging substance in the presence of carbon carriers and an oxygen-containing gas to produce molten pig iron or liquid steel pre-products and a CO and H 2 -containing reducing gas, a means for supplying the carbon carrier and the oxygen-containing gas to the melter gasifier, a first conveyor for conveying the preheated charging substance from the first preheating reactor to the first reduction reactor, a first gas conveyor for conveying the reducing gas from the melter gasifier to the first reduction reactor, a second conveyor for conveying reduction product from the first reduction reactor to the meltergasifier, *r
S
4
S
S. (viii) a second gas conveyor for conveying a top gas produced in the first reduction reactor from that reactor to the first preheating reactor, (ix) a second fluidised bed preheating reactor for preheating a second charging substance, a second fluidised bed reduction reactor for reducing the preheated second charging substance to produce a reduced product, stofuan/keopi49134,93.DIVISionAL 0.10.88 6 (xi) a means for compressing and briquetting the reduced product of step (xii) a third conveyor for conveying the preheated second charging substance from the second preheating reactor to the second reduction reactor, (xiii) a fourth conveyor for conveying the reduced product of step to the compressing and briquetting means, and (xiv) a third gas conveyor for conveying an export gas produced in the first preheating reactor from that reactor to the second reduction reactor via a CO 2 scrubber and a heating means.
Preferably, the plant further comprises a fourth gas conveyor interconnecting the second reduction reactor and the third gas conveyor for conveying top gas from the second reduction reactor to the third gas conveyor for mixing of the top gas and the export gas before the admixed gas is passed to the CO, scrubber.
Preferably, the second reduction reactor the second reduction reactor comprises a cylindrical lower section, a cylindrical upper section having a diameter greater than the lower section, and a conical transition section, and said third gas conveyor is arranged for supplying export 25 gas into said conical transition section.
Preferably, a fines discharge means the second reduction reactor comprises a fines discharge means and the plant further comprises a fines conveyor for conveying fines from the fines discharge means to the briquetting means.
stafutnakeWI49l34.9DVISlONAL 30.10.96 ~u 7 The present invention will now be described in detail by reference to a preferred embodiment of the invention schematically illustrated in Figures 1-3. Figures 1 and 2 schematically illustrate the "first arrangemen.; of the invention that is also the subject of parent patent application 49134/93.
Figure 3 schematically illustrates the "second arrangement" of the invention which, when combined with a "first arrangement" of the type illustrated in Figure 1 or Figure 2 via gas ducts 6 and/or 42, constitutes one preferred embodiment of the present invention.
**o 4 *eeS* 4* staf~uan/keepl49134.93.IVISIONAL 30.10,96 8 By 1 a preheating reactor is denoted, which is designed as a whirl-layer preheating reactor and into which charging substances containing iron ore and fluxes are chargeable via a charging duct 3 entering laterally on the level of the whirl-bed zone 2 (preheating zone). On the upper end of the shaft-likely designed whirl-layer preheating reactor 1, the gases formed therein and flowing therethrough are withdrawn via a gas discharge duct 6 equipped with a gas purifying cyclone 4 and a gas scrubber 5, such as a Venturi scrubber. These gases are available as hiqh-quality export gases having a calorific value of about 8000 kJ/Nm 3 for various purposes, for the production of current with or without oxygen.
All of the charging substances preheated in the whirl-layer preheating reactor 1, via a conveying duct 7, reach a reduction reactor 8 also designed as a whirl-layer reactor and are completely reduced to a major extent in the same.
Via a pneumatic sponge-iron conveying duct 9 (including an N 2 injector) any 2 other forced conveyance could be provided instead the sponge ircn formed in the whirl-layer reduction reactor 8 gets into a melter gasifier 10 by being introduced into the same on the level of afluidized bed iT, II provided in the melter gasifier and/or on the level of a fixed bed I located therebelow. The melter gasifier comprises at least one supply duct 11 for coal and fluxes as well as tuyere feeds 12 for oxygen-containing gases arranged on several levels.
0 Il~ed~BI~IIILI- e- -9- Molten pig iron 13 and liquid slag 14 collect in the melter gasifier 10 below the melting-gasifying zone formed by a fixed bed I, a coarse coke fluidized bed II located thereabove, a fine coke fluidized bed III located above the latter and a killing pace IV located on top, the pig iron and the liag being tapped separately via a tapping means 16 each. In the melter gasifier 10, a reducing gas is produced from the carbon carriers and from the oxygen-containing gas, which reducing gas collects in the killing space IV above the fluidized bed III and is fed to the whirl-layer reduction reactor 8 through a gas duct 17, via a frustoconica! constriction of the substantially shaft-shaped whirl-layer reduction reactor F, constituting a gas distributing bottom 9 and provided for the purpose of forming a whirl layer 18 or a whirl bed 18 (reduction zone), the reducing gas being supplied via the periphery of the constriction by means of an annular duct The large solids particles, which cannot be kept floating in the whirl layer, centrally descend due to the effect of gravity and are withdrawn through a central solids discharge 21. This central solids discharge 21 is configured such that, via a radial gas feed means 22, a fixed-bed flow is formed into the cylindrical vessel part 23 having a 9** conical bottofi 24 and arranged below the frustoconical gas distributing bottom 19 4- such that the reduedon even of large particles can be achieved to a satisfactory extent.
Due to the frustoconical shape of the gas distributing bottom 19, the clear tube velocity changes with the height. As a result, a special grain size distribution adjusts 3 0 over the height of the gas distributing bottom 19. By appropriately arranging the tuyeres in the gas distributing bottom 19, an intemrnly circulating whirl layer can, 1us, be formed, where the gas velocity is higher in the center than on the periphery. The formation of a whirl layer o' this type may be used both for the reduction reactor 8 and for the preheating reactor 1.
I 10 A portion of the reducing gas leaving the melter gasifier 10 is subjected to purification in a hot cyclone 25, to cooling in a consecutively arraiged scrubber 26, and, via a compressor 27, is again admixed to the reducing gas leaving the melter gasifier 10 via a gas duct 28. The dust separated in the hot cyclone 25 is returned into the melter gasifier 10 via an N 2 injector 29. A portion of the still uncooled reducing gas leaving the hot cyclone 25 reaches the whirl-layer reduction reactor 8 through its cylindrical vessel part 23 via the gas feed means 22 formed by an annular duct.
The gas withdrawn from the whirl-layer reduction reactor 8, via a gas duct 30, is fed to a reduction cyclone 31, in which fines still contained in the reducing gas are separated and reduced completely. These fines are introduced into the melter gasifier approximately on the level of the upper end of the fixed bed I via a conveying duct 42 and an N 2 injector 33.
The partially oxidized reducing gas emerging from the reduction cyclone 8, via the gas duct 30, gets into the whirl-layer preheating reactor 1, wherein, however, part of i~ the same is burnt for heating the reducing gas in a combustion chamber 34, into which a duct 35 feeding an oxygen-containing gas enters.
From the whirl-layer reduction reactor 8, a portion of the completely reduced charging substances is withdrawn on the level of the whirl bed 18 by means of a worm *conveyor 36 and, preferably together with the fines coming from the reduction cyclone 31, is introduced into the melter gasifier 10 approximately on the level of the upper end 0 of the fixed bed I by means of a conveying duct 37 via an N 2 injector 33.
The finely particulate material separated in the cyclone 4 of the export gas discharge 0 duct 6 is charged via a conveying duct 38 including sleuces 39 which are also provided in the other conveying ducts 32, 37 for the partially or completely reduced I IP C~ ~d~ 11 material through the annular duct 20 feeding the reducing gas into the whirl-layer reduction reactor 8.
The plant according to Fig 1, in detail, functions as follows: The fine ore treated sieved and dried and having a grain size distribution of, for instance, 0.044 mm =approx. 20 0. 044 6.3 mim approx. 70 6.3 12.7 mm approx. 10 and a moisture content of approximately 2 is charged into the preheating reactor 1 pneumatically or by aid of a steep belt or vertical conveyor. There, it is prehated to a temperature of about 8500'C in the whirl-bed zone 2 and optionally is pre-reduced on account of the reducing atmosphere to about the wuestite stage.
For this pre-reduction procedure, the reducing gas is to contain at least 25 CO *fe H*12 in order to have sufficient reducing power.
at Subsequently, the preheated and optionally pre-reduced fine ore flows into the 040-0 "reduction reactor 8 preferably due to gravity in the whirl layer or whirl bed 18 of which the fine ore is largely reduced to the Fe stage at a temperature of about 8500 C.
*t For this reduction procedure, the gas is to have a content of CO H 2 of at least 68 00o In the reduction reactor 8, screening of the fine ore takes place, the portion of below 0.2 mm being entrained by the reducing gas into the reduction cyclone 31.
0 There, the complete reduction of the fine ore of below 0.2 min occurs during the separation of the solids by the cyclone effect The finer solids portion discharged from the whirl layer 18 of the reduction reactor 8 by oid of the discharge wormn 36 is supplied to the melter gasifier 10 in the region of -IC 12 the blow-in planes of the oxygen-containing gases via sleuces 39, together with the fine ore separated in the reduction cyclone 31, by aid of the N 2 injector 33.
The coarser solids portion from the lower region of the reduction reactor 8 is blown or charged into the melter gasifier 10 in the region of the fine-coke fluidized bed III via sleuces 39 and by aid of the N 2 injector 9 or by means of gravity discharge.
The dust separated in the hot cyclone 25 (primarily containing Fe and C) is fed to the melter gasifier 10 in the region between the fine-coke fluidized bed III and the coarse-coke fluidized bed II via sleuces 39 by aid of the N 2 injector 29 and by means of an oxygen dust burner.
For the purpose of preheating and calcining, the fluxes required for the process are charged as coarse grains, preferably having grain sizes ranging between 4 and 12.7 mm, via the coal path (11) and as fine grains, preferably having grain sizes ranging between 20 2 and 6.3 mm, via the fine-ore path For fine ores requiring longer reduction times, a second (as well as, if required, a Sthird) whirl-layer reduction reactor 8' including an additional reduction cyclone 31' is provided in series or in succession to the first reduction reactor 8, as is illustrated in 25 Fig. 2. The fine ore is reduced to the wuestite stage in the second reduction reactor 8' 0 and to the Fe stage in the first reduction reactor 8.
SIn this case, the solids portion discharged from the whirl layer 18' of the second reduction reactor by aid of the discharge worm 36' is charged into the first reduction reactor 8 by gravity, together with the coarser solids portion from the lower region of the second reduction reactor The fine ore separated in the second reduction cyclone 31' is supplied to the melter gasifier 10 in the region of the blow-in planes of the oxygen-containing gases by aid of the N 2 injector 33, together with the fine ore separated in the first reduction cyclone 31.
be 9- lsl F-rh I ~C 1 -I 13 If, when using two whirl-layer reduction reactors 8, 8' and two reduction cyclones 31, 31', the operational pressure does not suffice to balance out pressure losses in the system, the gas mixture required for the preheating reactor 1, according to the invention, is brought to the necessary pressure by aid of a compressor 40. In this case, the gas from the second reduction cyclone 31' is cleaned in a scrubber 41. However, in 1 the following, only a partial stream of the gas is compressed a portion being withdrawn through duct 42 as export gas and is appropriately mixed with an oxygencontaining gas fed through duct 44 in a mixing chamber 43 such that a partial combustion of the reducing gas subsequently can occur in the preheating reactor 1 for the purpose of attaining the fine-ore preheating temperature required.
The high-quality export gas from the pig iron production may be used for the production of current with or without oxygen, as indicated above. According to a 0 preferred embodiment of the invention, which is represented in Fig. 3, the export gas, after CO 2 scrubbing 45 and preheating 46 to about 850°C, is re-used as a reducing gas, in the following manner: To produce hot-briquetted iron, fine ore of the same specification as used for the production of pig iron is preheated and reduced by the reducing gas in the same aggregates as used in pig iron production. The completely reduced grain fractions from the at least one reduction reactor 8 and from the reduction cyclone 31 are blown into a charging bunker 47 by aid of N 2 injectors 33. Alternatively, the coarser grain fraction can be charged from the lower region of the reduction reactor 8 into the charging bunker 47 by a gravity discharge.
After this, the completely reduced fine ore having a degree of metallization of about 92 and a temperature of at least 750°C reaches a roll briquetting press 49 due to gravity via a pre-compressing worm 48 including a controllable motor.
1~8- 111 B ~1 I 14 In the following examples, typical characteristic data of the process according to the invention obtained in operating the plants according to the embodiments represented in Figs. 1 to 3 are summarized.
Example: Coal analysis (dry analysis values)
I
A
S
ashes Cfix Ore analysis (moist analysis values) Fe Fe 2 03 CaO MgO SiO 2 A1 2 0 3 MnO losses on ignition moisture 77 1.8% 7.6% 9.1% 61.5 62.84% 87.7 0.73 0.44% 6.53% 0.49 0.15 0.08 2 0***SS e I L 15 Grain size distribution of fine ore 10 mm 0 6 mm 5.8 6-2 mm 44.0 2 0.63 mm 29.6 0.63 0.125 mm 13.0 -0.125 mm 7.6 Fluxes (dry analysis values) CaO 45.2 MgO 9.3 Si02 1.2 A1 2 03 0.7 0 MnO 0.6 20 Fe 2 03 2.3 losses on ignition 39.1 For the production of 42 tons of pig iron/hour in the plant according to Fig. 1, 42 25 tons of coal/hour are gassed with 29,000 Nm 3 0 2 /hour. The ore consumption therefor amounts to 64 tons/hour and the consumption of fluxes is 14 tons/hour.
In addition to iron, the pig iron produced has the following composition: C 4.2 Si 0.4 p 0.07 Mn 0.22% S 0.04% i I ISIIL I 16 The export gas from the pig iron plant incurs at 87,000 Nm 3 /hour, having the following analysis: CO 36.1
CO
2 26.9
H
2 16.4
H
2 0 1.5
N
2 +Ar 18.1
CH
4 1
H
2 S 0.02 Calorific value 6780 kJ/Nm 3 When further utilizing the export gas from the pig iron plant for the production of hot-briquetted iron according to Fig. 3, 29 tons of hot-briquetted irc:houx an be produced. The amount of recycled gas required therefor is 36,000 1'rAw. The hot- 20 briquetted sponge iron has the following analysis values: Metallization 92 C 1 S 0.01% P 0.03% The amount of export gas from the plant for the production of hot-briquetted iron is 4 79,000 Nm 3 /hour, the gas having the following composition: CO 21.6
CO
2 44.1
H
2 10.6
H
2 0 2.8
N
2 +Ar 19.9 1 p 4~9a r 17
CH
4 1 Calorific value 4200 kJ/Nm 3 The necessary electric input of the pig iron plant and of the plant for the production of hot-briquetted iron is 23 MW. The export gas after the plant for the production of hot-briquetted iron corresponds to a thermal output of 145 MW.
r-
Claims (12)
1. A process for producing molten pig iron or liquid steel pre-products and for producing hot-br:,quetted iron, which process comprises: preheating a first charging substance which comprises iron ore in a fluidised bed of a first preheating zone so as to obtain a preheated charging substance, (ii) substantially reducing said preheated charging substance form a reduced charging substance in a fluidised bed of a first reduction zone, (iii) melting the reduced charging substance of step (ii) in a melting gasifying zone in the presence of carbon carriers and an oxygen-containing gas 15 to produce a CO and H 2 -containing reducing gas, (iv) directing the reducing gas of step (iii) into the first reduction zone of step (ii) and reacting the reducing gas with the preheated charging substance to produce a top gas, 20 directing the top gas of step (iv) to the first preheating zone for preheating the first charging substance and withdrawing the gas as an export gas, (vi) removing CO, from the export gas and heating the export gas by directing the export gas through a CO 2 scrubber and a preheating means, staWetankeep49134.93DVISIONAL 30.1%.96 i n i 4 IIIC 19 (vii) preheating a second charging substance which comprises iron ore in a second preheating zone so as to obtain a preheated charging substance, (viii) substantially reducing the preheated charging substance of step (vii) with the CO 2 scrubbed and preheated export gas of step (vi) in a fluidised bed of a second reduction zone to produce a reduced product, and (ix) compressing and briquetting the reduced product of step (vii).
2. The process as claimed in claim 1 wherein the preheating step (vi) comprises partially combusting the o: export gas to elevate the gas temperature.
3. The process as claimed in claim 1 or claim 2, 15 comprises mixing the export gas with a portion of the top 00* gas of step (iv) before removing CO 2 from the export gas in CO, scrubbing step (vi). :0
4. The process as claimed in any one of claims 1 to 3 wherein step (vi) comprises CO 2 scrubbing the export gas S 20 and thereafter heating the export gas to approximately 8500C.
5. The process as claimed in any one of claims 1 to 4 comprises injecting the reduced product of step (viii) into a charging bunker for subsequent compressing and briquetting by aid of N 2 injectors.
6. The process as claimed in any one of claims 1 to 4 comprises discharging the reduced product of step (viii) from a lower region of the second reduction zone into a charging bunker by gravity discharge. stafuanrkeopl49134.91OIVISIONAL 30.10.96 I 20
7. The process as claimed in any one of claims 1 to 6 wherein the degree of metallisation of the reduced product of step (viii) is approximately 92%.
8. The process as claimed in any one of claims 1 to 7 wherein the reduced product of step (viii) has a temperature of at least 750 0 C when it is subjected to briquetting.
9. A plant for producing molten pig iron or liquid steel pre-products and for producing hot-briquetted iron, which plants comprises: a first fluidised bed preheating reactor for preheating a first charging substance which comprises iron ore, S (ii) a first fluidised bed reduction reactor downstream of the first preheating reactor for reducing the preheated charging substance to produce a reduced charging substance, S. o S (iii) a melter-gasifier for melting the reduced charging substance in the presence of carbon S 20 carriers and an oxygen-containing gas to produce "molten pig iron or liquid steel pre-products and a CO and H 2 -containing reducing gas, (iv) a means for supplying the carbon carrier and the oxygen-containing gas to the melter gasifier, a first conveyor for conveying the preheated charging substance from the first preheating reactor to the first reduction reactor, stafluanee4934.9DIVISIONAL 30.10.9G -I la II I 21 (vi) a first gas conveyor for conveying the reducing gas from the melter gasifier to the first reduction reactor, (vii) a second conveyor for corneying reduction product from the first reduction reactor to the melter- gasifier, (viii) a second gas conveyor for conveying a top gas produced in the first reduction reactor from that reactor to the first preheating reactor, (ix) a second fluidised bed preheating reactor for preheating a second charging substance, a second fluidised bed reduction reactor for reducing the preheated second charging substance to produce a reduced product, 15 (xi) a means for compressing and briquetting the reduced product of step a**e (xii) a third conveyor for conveying the preheated :'cond charging substance from the second preheating reactor to the second reduction 20 reactor, *9S*SS (xiii) a fourth conveyor for conveying the reduced product of step to the compressing and briquetting means, and (xiv) a third gas conveyor for conveying an export gas produced in the first preheating reactor from that reactor to the second reduction reactor via a CO, scrubber and a heating means. staffIunrnkeep/49134O3.DIVISIONAL 30.'J 96 I h 22 The plant as claimed in claim 9 further comprises a fourth gas conveyor interconnecting the second reduction reactor and the third gas conveyor for conveying top gas from the second reduction reactor to the third gas conveyor for mixing of the top gas and the export gas before the admixed gas is passed to the CO 2 scrubber.
11. The plant as claimed in claim 9 or claim wherein the second reduction reactor comprises a cylindrical lower section, a cylindrical upper section having a diameter greater than the lower section, and a conical transition section, and said third gas conveyor is arranged for supplying export gas into said conical transition section.
12. The plant as claimed in any one of claims 9 to 11 15 wherein the second reduction reactor comprises a fines discharge means and the plant further comprises a fines conveyor for conveying fines from the fines discharge means 0to the briquetting means.
13. A process substantially as herein described with S 20 reference to figure 3 of the drawings. o 14. A plant substantially as herein described with o0 reference to figures 3 of the drawings. DATED THIS 30TH DAY OF OCTOBER 1996. 1) VOEST-ALPINE INDUSTRIEANLAGENBAU GmbH, 2) RESEARCH INSTITUTE OF INDUSTRIAL SCIENCE TECHNOLOGY INCORPORATED FOUNDATION, and 3) POHANG IRON STEEL CO., LTD By its Patent Attorneys: GRIFFITH HACK CO Fellows Institute of Patent Attorneys of Australia staluafnIeeop/49134.9aDIVISIONAL 30.10.96 r II ABSTRACT, A process for producing molten pig iron or liquid steel pre-products and for producing hot-briquetted iron, which process comprises: preheating a first charging substance which comprises iron ore in a fluidised bed of a first preheating zone so as to obtain a preheated charging substance, (ii) substantially reducing said preheated charging substance to forts a reduced charging substance in a fluidised bed of a first reduction zone, *a a ,a (iii) melting the reduced charging substance of step (ii) in a melting gasifying zone in the presence of carbon carriers and an oxygen-containing gas to produce a CO and H 2 -containing reducing gas, a* (iv) directing the reducing gas of step (iii) into the first reduction zozs of step (ii) and reacting the reducing gas with the preheated charging substance to produce a top gas, S 20 directing the top gas of step (iv) to the first preheating zone for preheating the first charging substance and withdrawing the gas as an export gas, (vi) removing CO0 from the export gas and heating the export gas by directing the export gas through a CO 2 scrubber and a preheating means, (vii) preheating a second charging substance which comprises iron ore in a second preheating zone so as to obtain a preheated charging substance, stIauan/kap/4913493.IVISINAL 0,10 W 1~WI~YB ID~II;III;L YI3~1* -2 (Viii) substantially reducing the preheated charging substance of step (vii) with the CO 2 scrubbed and preheated e2xport gas of step (vi) in a fluidised bed of a second reduction zone to produce a reduced product, and (ix) compressing and briquetting the reduced product of step (vii). too O006 6680 C.6 S S stafuan/keep/49134.93.DIVISIONAL 30A0.96
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU70556/96A AU681836B2 (en) | 1992-10-22 | 1996-11-01 | Process for producing molten pig iron or molten steel pre-products |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT2096/92 | 1992-10-22 | ||
| AU70556/96A AU681836B2 (en) | 1992-10-22 | 1996-11-01 | Process for producing molten pig iron or molten steel pre-products |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU49134/93A Division AU675245B2 (en) | 1992-10-22 | 1993-10-21 | Process for producing molten pig iron or molten steel pre-products |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU7055696A AU7055696A (en) | 1997-02-13 |
| AU681836B2 true AU681836B2 (en) | 1997-09-04 |
Family
ID=3753724
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU70556/96A Ceased AU681836B2 (en) | 1992-10-22 | 1996-11-01 | Process for producing molten pig iron or molten steel pre-products |
Country Status (1)
| Country | Link |
|---|---|
| AU (1) | AU681836B2 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1243733A (en) * | 1959-01-01 | 1960-10-14 | British Iron Steel Research | Process for the reduction of metalliferous ores, in particular iron ores for the production of iron |
| EP0217331A2 (en) * | 1985-10-03 | 1987-04-08 | Deutsche Voest-Alpine Industrieanlagenbau Gmbh | Process for producing pig iron from finely divided ores |
-
1996
- 1996-11-01 AU AU70556/96A patent/AU681836B2/en not_active Ceased
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1243733A (en) * | 1959-01-01 | 1960-10-14 | British Iron Steel Research | Process for the reduction of metalliferous ores, in particular iron ores for the production of iron |
| EP0217331A2 (en) * | 1985-10-03 | 1987-04-08 | Deutsche Voest-Alpine Industrieanlagenbau Gmbh | Process for producing pig iron from finely divided ores |
Also Published As
| Publication number | Publication date |
|---|---|
| AU7055696A (en) | 1997-02-13 |
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