EP0117928B1 - Verfahren zur Erzeugung von Stahl durch Einschmelzen von Eisenschwamm im Lichtbogenofen - Google Patents

Verfahren zur Erzeugung von Stahl durch Einschmelzen von Eisenschwamm im Lichtbogenofen Download PDF

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Publication number
EP0117928B1
EP0117928B1 EP83201854A EP83201854A EP0117928B1 EP 0117928 B1 EP0117928 B1 EP 0117928B1 EP 83201854 A EP83201854 A EP 83201854A EP 83201854 A EP83201854 A EP 83201854A EP 0117928 B1 EP0117928 B1 EP 0117928B1
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EP
European Patent Office
Prior art keywords
furnace
electric
process according
arc furnace
direct reduction
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83201854A
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German (de)
English (en)
French (fr)
Other versions
EP0117928A1 (de
Inventor
Lothar Formanek
Martin Hirsch
Wolfram Dr. Schnabel
Harry Dr. Serbent
Detmar Arlt
Klaus-Dietrich Fritzsche
Heribert Koenig
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vodafone GmbH
GEA Group AG
Original Assignee
Metallgesellschaft AG
Mannesmann AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Metallgesellschaft AG, Mannesmann AG filed Critical Metallgesellschaft AG
Publication of EP0117928A1 publication Critical patent/EP0117928A1/de
Application granted granted Critical
Publication of EP0117928B1 publication Critical patent/EP0117928B1/de
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/5252—Manufacture of steel in electric furnaces in an electrically heated multi-chamber furnace, a combination of electric furnaces or an electric furnace arranged for associated working with a non electric furnace
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/12—Making spongy iron or liquid steel, by direct processes in electric furnaces

Definitions

  • the invention relates to a method for producing steel by melting sponge iron in an electric arc furnace, the sponge iron being produced by direct reduction.
  • the arc furnace operation is also inevitably associated with strongly fluctuating energy consumption due to its characteristic and, moreover, discontinuous mode of operation. These fluctuations extend both to the chronological sequence and to the absolute amount of the decrease in energy.
  • An electrical network is required to connect an arc furnace because it is so strong that the reaction - due to furnace operation - does not exceed the maximum permissible limit values.
  • the object of the invention is to provide a method which makes it possible to enable the advantageous operation of the arc furnace with sump by ensuring that hot metal is sufficiently available and at the same time that the process sequence is as economical as possible.
  • the invention solves this problem in that the sponge iron is reacted on a bath of liquid, carbon-containing iron in the Uchtbogenofen, wherein the liquid, carbon-containing iron (hot metal) is also generated from sponge iron or pre-reduced ore in an electric reduction furnace, which is dependent on the is regulated by the electric arc furnace-induced load fluctuations so that a practically constant load on the electrical network results.
  • the process according to the invention thus achieves an overall effect by combining a process step in which the carbon-containing iron required for the sump in the arc furnace is obtained - and preferably from the same starting material as is used in the arc furnace - with the melting of the sponge iron in the arc furnace , which goes beyond the sum of the individual processes taking place in the process sections, because the load on the electrical network is largely evened out in a surprisingly simple manner at the same time as the melting process is improved.
  • arc furnace Under the expression arc furnace. are to be understood as directly heated arc furnaces, in which the heating is carried out by electric arcs burning between the electrodes and the metallic insert or the steel bath (direct arc furnace).
  • the term “electric reduction furnace” means furnaces in which the electrodes are either immersed in an open slag bath or in a standing Möller column and in which the energy conversion takes place preferably by means of resistance heating (submerged arc furnace). These furnaces are well suited for reduction work, even with an open slag bath. From sponge iron and added carbon carriers, they produce carbon-containing iron, which is used in the arc furnace as a sump.
  • the electric reduction furnaces can be operated with variable power consumption.
  • the waste heat resulting from the direct reduction in the exhaust gas and the energy carriers occurring during or direct reduction and / or for the direct reduction are used to generate electrical energy to cover the energy requirements of the electric reduction furnace and arc furnace combination.
  • Energy sources can be excess solid, carbon-containing materials or combustible gases which are produced in the direct reduction or excess which are produced in the production of the reducing medium for the direct reduction. flammable gases or solid, carbonaceous materials.
  • An advantageous embodiment consists in that the amount and the analysis of the carbon-containing iron used as the sump in the arc furnace are selected such that the total carbon balance is balanced during the charging of sponge iron in the arc furnace, the active power of the arc furnace being regulated in such a way that the arc furnace is in the thermal equilibrium necessary for melting iron sponge. Thermal equilibrium means that there is no overheating and no freezing.
  • Another advantageous embodiment consists in the fact that sponge iron with a lower degree of metallization is mainly used for the production of liquid, carbon-containing iron (hot metal) in the electric reduction furnace.
  • An advantageous embodiment consists in that the excess carbon-containing material separated from the discharge of the direct reduction with solid carbon-containing reducing agents is at least partially burned in a combustion unit with the addition of oxygen-containing gases, the hot combustion gases and the exhaust gas of the direct reduction are used to generate electrical energy, wherein the amount of electrical energy generated is controlled so that this corresponds at least to the maximum energy requirement of the arc furnace plus the minimum energy requirement of the electric reduction furnace, and that the energy not required by the arc furnace is converted in the electric reduction furnace.
  • the excess carbonaceous material is completely burned if its quality is not suitable for use in the electric reduction furnace or if an addition is not required there. Good quality means that the ash and sulfur content is relatively low and the ash is basic. It is also possible to process the separated carbonaceous material and then to insert the good quality fraction into the electric reduction furnace and the poor quality fraction into the combustion.
  • the minimum energy requirement of the electric reduction furnace is the holding power.
  • the sensible heat of the hot combustion gases and the exhaust gases from the direct reduction are used to generate steam, and the steam drives a generator to generate electricity via steam turbines.
  • the hot combustion gases and the exhaust gases from the direct reduction are expediently conducted separately into separate steam generators and the steam flows into separate turbines.
  • the turbine for the steam of the exhaust gas of the direct reduction can always be operated in the optimal range, and better utilization and control is possible.
  • the amount of electrical energy generated must correspond to the maximum energy requirement of the electric arc furnace plus the minimum energy requirement of the electric reduction furnace. More electrical energy can also be generated for other purposes of one's own operation, but this additional generation is then not included in the regulation of the current distribution.
  • the electrical energy is distributed in such a way that the energy requirement of the arc furnace is always "met", i.e. if it has high energy requirements, the electric reduction furnace receives less electrical energy, and when the arc furnace is switched off, the electric reduction furnace receives more energy.
  • the sponge iron is divided in such a way that the amount of carbon-containing iron (hot metal) required for steel production in the electric arc furnace is obtained in the electric reduction furnace.
  • the sponge iron can be used hot in the smelting furnaces.
  • the combustion of the excess carbonaceous material can take place in fluidized bed apparatuses or dust fires, such as e.g. B. cyclone firing.
  • a preferred embodiment is that the exhaust gas from the direct reduction is afterburned before use in electrical power generation.
  • a preferred embodiment is that further combustible material is charged into the combustion unit. As a result, self-sufficient operation can be carried out even when the heat in the exhaust gas and the hot combustion gases of the excess carbonaceous material are too low.
  • combustion unit is a circulating fluidized bed.
  • the circulating fluidized bed works without a jump in the material density between the dense phase and the dust space above.
  • the solids concentration decreases continuously from bottom to top.
  • the areas are: or where and are.
  • a preferred embodiment consists in that a flammable gas is generated by separate smoldering and / or partial gasification of solid, carbon-containing material, the combustible gas is used to generate electrical energy and the smoldered solid, carbon-containing material in the direct reduction and / or the electroreduction furnace and / or the combustion unit is used. Direct reduction is relieved by the use of carbon-containing material on the exhaust side and its throughput is increased. Since the exhaust gases from the direct reduction contain fewer combustible gaseous components, less electrical energy is generated by the exhaust gas, i. H. the non-controllable base load becomes smaller and the control possibility of the electrical energy generated by the combustion increases.
  • Part of the carbonized material, or possibly everything, can be fed into the combustion unit, so that the quantity charged in the direct reduction is also largely flexible.
  • the generation of electrical energy by the combustible gases is very flexible. Some of the flammable gas can also be used for other purposes in your own company.
  • a preferred embodiment is that the smoldering and / or partial gasification takes place in a circulating fluidized bed.
  • the circulating fluidized bed is very suitable and flexible to operate.
  • a particularly suitable method is described in EP-A-0 062 363. If the carbonized material from the gasification stage is used in the direct reduction, no charging takes place in the combustion stage.
  • a preferred embodiment consists of the fact that combustible gas is stored in a gas storage device and is removed when necessary to generate electrical energy. A very good flexibility is achieved through this storage, and reserves are also created especially for the start-up and shutdown operations.
  • a preferred embodiment is that the combustible gas is used to generate electrical energy using a gas turbine.
  • a very fast regulation of the amount of energy generated is possible with a gas turbine.
  • a preferred embodiment is that baking coals are used in the circulating fluidized bed. This makes it possible to use these coals without additional effort, which cannot be used directly in direct reduction.
  • One embodiment consists of the fact that the excess carbon-containing material separated from the discharge of the direct reduction is used in the electric reduction furnace, additional energy sources are burned in a combustion unit with the addition of oxygen-containing gases, the hot combustion gases and the exhaust gas of the direct reduction are used to generate electrical energy , wherein the amount of electrical energy generated is controlled so that it corresponds at least to the maximum energy consumption of the arc furnace plus the minimum energy requirement of the electric reduction furnace, and that the energy not required by the arc furnace is converted in the electric reduction furnace.
  • the separated excess carbon is completely added to the electric reduction furnace when this carbon is of good quality and is required in the electric reduction furnace.
  • a preferred embodiment is that the direct reduction is carried out in a rotary kiln.
  • the coals used as reducing agents mostly contain higher levels of volatile components, such as. B. lignite, and have a high reactivity.
  • FIG. 1 shows. is charged into the rotary kiln 1 iron ore 2 and reduced to sponge iron.
  • the discharge material 3 is separated in a separation stage 4 into sponge iron 5 and excess carbon-containing material, of which a part 6a is passed into the electric reduction furnace 7 and the other part 6b into the circulating fluidized bed 8 and is burned by means of air 9.
  • the hot combustion gas 10 is fed into the steam generator 11.
  • a generator 13 is driven with the steam 12.
  • the electrical energy generated is fed via line 14 to the electric reduction furnace 7 and the arc furnace 16.
  • the exhaust gas 17 of the rotary kiln 1 is afterburned in a post-combustion chamber 18 with the addition of air 19.
  • the hot gas 20 is fed into the steam generator 21.
  • a generator 23 is driven with the steam 22.
  • the electrical energy generated is fed into line 14 via line 24.
  • the iron sponge 5 is charged in part 5a in the electric reduction furnace 7 and in part 5b in the arc furnace 16.
  • the pig iron produced in the electric reduction furnace 7 is charged into the arc furnace 16, from which the steel 25 is drawn off. As much electrical energy as is required is always supplied to the arc furnace 16 via line 14a. The remaining electrical energy is fed into the electric reduction furnace 7 via line 14b.
  • the rotary kiln 1 can be operated with coal with a high proportion of volatile components. which are charged via 26 into the loading end and are partly blown into the discharge end by the blowing device 27.
  • the exhaust gas 17 contains higher proportions of combustible gaseous components and the amount of electrical energy generated in 24 is correspondingly large.
  • coal 29 can additionally be smelted and partially burnt with gases 30 containing oxygen.
  • the combustible gas 31 is burned in a gas turbine 32 that drives a generator 33.
  • the electrical energy generated is fed into line 14 via line 34.
  • the smoldered carbon-containing material is charged from the fluidized bed 28 via line 35 into the rotary kiln 1. In this case, no coal with a high proportion of volatile components is charged into the rotary kiln and the exhaust gas 17 contains only a small proportion of combustible, gaseous components.
  • the amount of electrical energy generated in 24 is correspondingly less.
  • the generation of electrical energy can be increased by adding coal 36 to the fluidized bed 8. Part of the carbonized material from the fluidized bed 28 can be fed into the fluidized bed 8 via line 37.
  • Flammable gas is stored in the gas store 38 and removed if necessary. Flammable gas can be withdrawn for operation via line 39 if this amount is scheduled for generation.
  • the liquid, carbon-containing iron produced in the electric reduction furnace is adjusted in terms of quantity and analysis - mainly carbon - in such a way that the total carbon balance is balanced when the sponge iron is charged. If, e.g. B. by a mistake in sponge iron production, sponge iron of a lower degree of metallization, z. B. instead of 92% only 85%, this can still be processed. However, the spongy iron is only used to charge the electric reduction furnace. It is therefore possible to operate the process with spongy iron with different degrees of metallization.
  • the steam generated in the steam generator 11 can also be passed to the steam generator 21 via line 12a.
  • FIG. 2 shows a typical load diagram for three arc furnaces and two electric reduction furnaces that work in a combined operation.
  • the time in minutes is plotted on the x-axis and the active power in megawatts on the y-axis.
  • the dotted curve shows the sum of the active powers of the electric reduction furnaces
  • the dashed curve shows the sum of the active powers of the arc furnaces
  • the solid curve shows the sum of the active powers of all melting furnaces.
  • the diagram shows the course of typical work cycles. In particular, it can be seen that the total active power of all furnaces is relatively constant, although the arc furnaces have very large fluctuations in power consumption.
  • the advantages of the invention are that the entire smelting process can be carried out independently of the performance of the available public supply network, that the operation takes place with minimal energy requirements per ton of steel, that the waste heat of the direct reduction producing the sponge iron is optimally used and that the excess carbon-containing material is used Material of the discharge of the direct reduction and possibly additionally used coal can be burned in an environmentally friendly manner by adding limestone with the accumulation of a landfillable CaS0 4 -containing residue.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture Of Iron (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Furnace Details (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
EP83201854A 1983-01-13 1983-12-29 Verfahren zur Erzeugung von Stahl durch Einschmelzen von Eisenschwamm im Lichtbogenofen Expired EP0117928B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3300867 1983-01-13
DE19833300867 DE3300867A1 (de) 1983-01-13 1983-01-13 Verfahren zur erzeugung von stahl durch einschmelzen von eisenschwamm im lichtbogenofen

Publications (2)

Publication Number Publication Date
EP0117928A1 EP0117928A1 (de) 1984-09-12
EP0117928B1 true EP0117928B1 (de) 1986-09-10

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ID=6188150

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Application Number Title Priority Date Filing Date
EP83201854A Expired EP0117928B1 (de) 1983-01-13 1983-12-29 Verfahren zur Erzeugung von Stahl durch Einschmelzen von Eisenschwamm im Lichtbogenofen

Country Status (10)

Country Link
US (1) US4490168A (enExample)
EP (1) EP0117928B1 (enExample)
JP (1) JPS59136409A (enExample)
AU (1) AU557005B2 (enExample)
BR (1) BR8400133A (enExample)
CA (1) CA1216754A (enExample)
DE (2) DE3300867A1 (enExample)
ES (1) ES528796A0 (enExample)
IN (1) IN158987B (enExample)
ZA (1) ZA84258B (enExample)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19933536A1 (de) * 1998-07-17 2000-01-27 Mitsubishi Heavy Ind Ltd Verfahren zur Herstellung von Stahl

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3334221A1 (de) * 1983-08-25 1985-03-14 Mannesmann AG, 4000 Düsseldorf Verfahren zur erzeugung von fluessigem, kohlenstoffhaltigem eisen aus eisenschwamm
US4564388A (en) * 1984-08-02 1986-01-14 Intersteel Technology, Inc. Method for continuous steelmaking
DE3428782A1 (de) * 1984-08-04 1986-02-13 Metallgesellschaft Ag, 6000 Frankfurt Verfahren zur erzeugung von eisenschwamm
AT387038B (de) * 1986-11-25 1988-11-25 Voest Alpine Ag Verfahren und anlage zur gewinnung von elektrischer energie neben der herstellung von fluessigem roheisen
AUPN639995A0 (en) * 1995-11-03 1995-11-30 Technological Resources Pty Limited A method and an apparatus for producing metals and metal alloys
AUPO276496A0 (en) 1996-10-07 1996-10-31 Technological Resources Pty Limited A method and an apparatus for producing metals and metal alloys
BE1011186A3 (fr) * 1997-05-30 1999-06-01 Centre Rech Metallurgique Procede de production de fonte liquide a partir d'eponge de fer et installation pour sa mise en oeuvre.
CN101392307B (zh) * 2007-12-07 2010-11-10 江苏沙钢集团有限公司 环保节能型电炉直接炼钢方法及其装置
DE102016215637A1 (de) 2016-08-19 2018-02-22 Robert Bosch Gmbh Kraftstoffeinspritzdüse
LU102322B1 (en) * 2020-12-17 2022-06-21 Wurth Paul Sa Green production route for low carbon, low nitrogen steel
EP4417713A1 (en) 2023-02-14 2024-08-21 Oterdoom, Harmen The novel two-step (semi-)continuous process for clean slag and steel or hot metal

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Publication number Priority date Publication date Assignee Title
BE503611A (enExample) *
US2894831A (en) * 1956-11-28 1959-07-14 Old Bruce Scott Process of fluidized bed reduction of iron ore followed by electric furnace melting
US3224871A (en) * 1961-02-24 1965-12-21 Elektrokemisk As Process of preheating ores for reduction in smelting furnace
US3206299A (en) * 1961-10-18 1965-09-14 Independence Foundation Dense-bed, rotary, kiln process and apparatus for pretreatment of a metallurgical charge
DE1508049A1 (de) * 1966-05-05 1969-10-02 Metallgesellschaft Ag Verfahren zur Verhuetung oxydischer eisenhaltiger Erze
DE2127847A1 (en) * 1970-06-05 1971-12-16 Gonzalez de,Castejon, Javier , Madrid Iron smelting - using low-grade ores and coal in low-cost appts
DD100017A5 (enExample) * 1971-11-01 1973-09-05
US3948641A (en) * 1972-03-04 1976-04-06 Klockner-Werke Ag Apparatus for the continuous production of steel from ore
US3891427A (en) * 1972-10-12 1975-06-24 Lectromelt Corp Method for melting prereduced ore and scrap
AT336052B (de) * 1975-08-08 1977-04-12 Voest Ag Vorrichtung zur verhuttung von eisenerzen
DE2624302C2 (de) * 1976-05-31 1987-04-23 Metallgesellschaft Ag, 6000 Frankfurt Verfahren zur Durchführung exothermer Prozesse
DE2628972C2 (de) * 1976-06-28 1983-12-01 Paderwerk Gebr. Benteler, 4794 Schloss Neuhaus Verfahren zur kontinuierlichen Erzeugung von Stahl
DE2841697A1 (de) * 1978-09-25 1980-04-10 Mannesmann Ag Verfahren zur herstellung von stahl aus eisenschwamm in elektrischen oefen
DE3113993A1 (de) * 1981-04-07 1982-11-11 Metallgesellschaft Ag, 6000 Frankfurt Verfahren zur gleichzeitigen erzeugung von brenngas und prozesswaerme aus kohlenstoffhaltigen materialien

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19933536A1 (de) * 1998-07-17 2000-01-27 Mitsubishi Heavy Ind Ltd Verfahren zur Herstellung von Stahl
DE19933536C2 (de) * 1998-07-17 2002-05-16 Mitsubishi Heavy Ind Ltd Verfahren zur Herstellung von Stahl

Also Published As

Publication number Publication date
JPS59136409A (ja) 1984-08-06
EP0117928A1 (de) 1984-09-12
DE3366151D1 (en) 1986-10-16
DE3300867A1 (de) 1984-07-19
AU557005B2 (en) 1986-11-27
US4490168A (en) 1984-12-25
BR8400133A (pt) 1984-08-21
CA1216754A (en) 1987-01-20
IN158987B (enExample) 1987-02-28
ZA84258B (en) 1985-08-28
ES8407102A1 (es) 1984-08-16
AU2325284A (en) 1984-07-19
ES528796A0 (es) 1984-08-16
JPH0373602B2 (enExample) 1991-11-22

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