EP0037809A1 - Procédé pour la production de fonte liquide ou de prématériau d'acier et dispositif pour la mise en oeuvre de ce procédé - Google Patents

Procédé pour la production de fonte liquide ou de prématériau d'acier et dispositif pour la mise en oeuvre de ce procédé Download PDF

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Publication number
EP0037809A1
EP0037809A1 EP81890058A EP81890058A EP0037809A1 EP 0037809 A1 EP0037809 A1 EP 0037809A1 EP 81890058 A EP81890058 A EP 81890058A EP 81890058 A EP81890058 A EP 81890058A EP 0037809 A1 EP0037809 A1 EP 0037809A1
Authority
EP
European Patent Office
Prior art keywords
fluidized bed
plasma
oxygen
melting vessel
raw material
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.)
Granted
Application number
EP81890058A
Other languages
German (de)
English (en)
Other versions
EP0037809B1 (fr
Inventor
Kurt Dipl.-Ing. Stift
Walter Dipl.-Ing. Dr. Lugscheider
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.)
Voestalpine AG
Deutsche Voest Alpine Industrieanlagenbau GmbH
Original Assignee
Voestalpine AG
Deutsche Voest Alpine Industrieanlagenbau GmbH
Korf Stahl 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 Voestalpine AG, Deutsche Voest Alpine Industrieanlagenbau GmbH, Korf Stahl AG filed Critical Voestalpine AG
Publication of EP0037809A1 publication Critical patent/EP0037809A1/fr
Application granted granted Critical
Publication of EP0037809B1 publication Critical patent/EP0037809B1/fr
Expired legal-status Critical Current

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Classifications

    • 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
    • C21B13/125—By using plasma
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/0006—Making spongy iron or liquid steel, by direct processes obtaining iron or steel in a molten state
    • C21B13/0013—Making spongy iron or liquid steel, by direct processes obtaining iron or steel in a molten state introduction of iron oxide into a bath of molten iron containing a carbon reductant
    • C21B13/002—Reduction of iron ores by passing through a heated column of carbon

Definitions

  • the invention relates to a process for the production of molten pig iron or steel raw material from iron oxide-containing raw material particles, in particular pre-reduced iron ore, in which the iron oxide-containing raw material particles are introduced from above into a fluidized bed formed from coal particles and an oxygen-containing carrier gas and heated, reduced and melted as they pass through, and also an installation for carrying out the process.
  • the oxygen-containing carrier gas must be introduced just above the slag bath surface, so that The fluidized bed extends up to this surface. For this reason, in the known processes, a zone with the highest temperature of the fluidized bed (high-temperature zone) is formed in the lower region of the fluidized bed, i.e. just above the surface of the slag bath. This has the disadvantage that reoxidation of the iron ore particles which have already been reduced cannot be avoided with certainty in this zone.
  • the invention aims to avoid these disadvantages and difficulties and has the object to provide a method of the type described above and a system for carrying out the method, in which the total energy input can be significantly reduced with much cheaper use of energy, so that the reduction and melting process can be carried out more economically than before.
  • This object is achieved in that additional energy is supplied to the fluidized bed by plasma heating.
  • the additional energy input by means of plasma heating makes it possible to significantly reduce the total energy input as a result of the energy transmission, which is predominantly carried out by radiation (due to the high temperature of the plasma gas).
  • the plasma heating takes place in the upper and / or adjoining central region of the fluidized bed and there creates and maintains a zone with the highest temperature of the fluidized bed.
  • the temperature just above the slag bath surface can be kept relatively low and reoxidation of the reduced (and already melted) iron ore particles just before passage through the slag bath can be avoided.
  • carbon carriers in solid and / or liquid form are advantageously introduced into the flame area of the plasma heater.
  • a reduction in the total energy input by up to 50% is possible if between 50 and 70% pre-reduced iron ore particles are introduced into the fluidized bed as iron oxide-containing raw material particles and are reduced in the fluidized bed.
  • Carbon carriers in solid and / or liquid form are advantageously blown into the fluidized bed from below.
  • inert gas is expediently blown into the fluidized bed from below.
  • a plant for carrying out the method has a refractory-lined melting vessel which has openings for the addition of carbon and iron oxide-containing raw material particles and openings for slag or melt tapping and openings for introducing the oxygen-containing carrier gas, and is characterized in that in height of the fluidized bed are used in the vessel wall plasma torch.
  • the plasma torches are expediently arranged in the upper and / or middle height range of the space of the melting vessel filled by the fluidized bed.
  • Nozzles for carbon carriers in solid and / or liquid form are advantageously provided adjacent to the plasma burners in the flame area of the plasma burners.
  • the plasma torches are directed in the direction of a central axis of the melting vessel and are arranged in a ring around the axis of the vessel, the plasma torches being provided one above the other in several planes.
  • the plasma torches are expediently pivotable, in particular horizontally and vertically pivotable.
  • a preferred embodiment of the system is characterized in that bottom nozzles are provided in the base, the melting vessel for the supply of a carbon carrier and / or of oxygen or an oxygen-containing gas and / or an inert gas.
  • indirect, ie equipped with a closed arc, plasma torch 12 which can be designed as a direct current or alternating current burner, are used in the direction of the axis 11 of the melting vessel 1.
  • the plasma torches 12 are expediently provided in a ring shape in the side walls in one or more planes, it being particularly advantageous if they can be pivoted both vertically in the direction of the arrows 13 and horizontally.
  • a portion of the reducing gas that flows through the opening 6 and is produced in the melting vessel 1 serves as the plasma-forming gas. It can also plasma-forming polyatomic gases and / or two or einatomi g e inert gases are used.
  • nozzles 14 are provided on the side walls 9, 10 of the melting vessel 1 for supplying carbon carriers, which introduce the carbon carriers, preferably solid or liquid carbon carriers, into the flame area of the plasma torch 12.
  • the oxygen-containing carrier gas which is used to produce the fluidized bed, is introduced into the melting vessel through gas nozzles 15, which are also arranged in the side walls of the melting vessel below the plasma torch. Both the nozzles 14 and the gas nozzles 15 can be pivoted to approximately the same extent as the plasma torches.
  • a slag tap hole 16 is provided just below the gas nozzles 15.
  • a metal tap hole 18 is arranged in the vicinity of the bottom 17 of the melting vessel.
  • the floor itself has a few further nozzles 19 to 23 through which coal and / or coke dust 24, oxygen 25, inert gas 26, natural gas 27 or liquid carbon carrier 28 are introduced into the melting vessel 1 can be directed.
  • the function of the melting vessel is as follows: the pre-reduced iron ore 8 introduced from above, preferably in free fall, reaches the fluidized bed 29, which extends from above the slag tap opening 16 to above the plasma torch 12, travels downward, is heated, reduced and in this melted.
  • the molten metal 30 collects below the slag layer 31.
  • the reduction gas is generated by plasma heating of liquid and / or solid carbon carriers which are introduced into the flame area of the plasma torch 12 through the nozzles 14. Another heat input for the required process heat is obtained from the partial combustion of the carbon carriers used. This combined gasification, reduction and melting process can take place at normal pressure as well as at elevated pressure.
  • the carbon carriers introduced through the floor nozzles 19 to 23 (coal and / or coke dust, liquid hydrocarbons, natural gas, SNG - synthetic natural gas) and the gases introduced through the floor nozzles (oxygen and / or inert gas) serve to make corrections to the heat balance of the Fluidized bed and to stabilize the flow conditions.
  • oxygen and / or inert gas serve to make corrections to the heat balance of the Fluidized bed and to stabilize the flow conditions.
  • a major advantage of introducing energy into the combined gasification, reduction and melting process by means of plasma heating is the energy transfer that is predominantly carried out by radiation, which is due to the high temperature (4000 to 15000 ° K) of the plasma gas.
  • the temperature just above the slag layer 31 can be kept relatively low, so that reoxidation of the already reduced iron ore can be avoided.
  • the likelihood of reoxidation in the upper or middle area of the fluidized bed is significantly lower than in the lower area of the fluidized bed and, if reoxidation does occur occasionally, this can occur in the area of the fluidized bed 29 below the high temperature zone, which area represents a compensation zone, so to speak , can be undone again.
  • the various operating conditions can always be optimally taken into account, e.g. different flow velocities within the melting vessel or the respective height of the fluidized bed, which again depends on the particle size of the ores and the coke supplied.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Manufacture Of Iron (AREA)
  • Catalysts (AREA)
EP81890058A 1980-04-03 1981-04-02 Procédé pour la production de fonte liquide ou de prématériau d'acier et dispositif pour la mise en oeuvre de ce procédé Expired EP0037809B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT1828/80 1980-04-03
AT0182880A AT367453B (de) 1980-04-03 1980-04-03 Verfahren und vorrichtung zur herstellung von fluessigem roheisen oder stahlvormaterial

Publications (2)

Publication Number Publication Date
EP0037809A1 true EP0037809A1 (fr) 1981-10-14
EP0037809B1 EP0037809B1 (fr) 1985-08-28

Family

ID=3521859

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81890058A Expired EP0037809B1 (fr) 1980-04-03 1981-04-02 Procédé pour la production de fonte liquide ou de prématériau d'acier et dispositif pour la mise en oeuvre de ce procédé

Country Status (16)

Country Link
US (1) US4396421A (fr)
EP (1) EP0037809B1 (fr)
JP (1) JPS56156708A (fr)
AT (1) AT367453B (fr)
AU (1) AU537907B2 (fr)
BR (1) BR8102003A (fr)
CA (1) CA1160056A (fr)
DD (1) DD157915A5 (fr)
DE (1) DE3171978D1 (fr)
ES (2) ES501074A0 (fr)
FI (1) FI68264C (fr)
NO (1) NO153144C (fr)
PH (1) PH18456A (fr)
PL (1) PL130491B1 (fr)
SU (1) SU1118292A3 (fr)
ZA (1) ZA812222B (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013133748A1 (fr) * 2012-03-08 2013-09-12 Valeas Recycling Ab Procédé et équipement de réduction de fer

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT372977B (de) * 1982-01-19 1983-12-12 Voest Alpine Ag Verfahren und einrichtung zur reduktion von oxidhaeltigen feinteiligen erzen
NL8201945A (nl) * 1982-05-12 1983-12-01 Hoogovens Groep Bv Werkwijze en inrichting voor de vervaardiging van vloeibaar ijzer uit oxydisch ijzererts.
AT378970B (de) * 1982-12-21 1985-10-25 Voest Alpine Ag Verfahren und vorrichtung zur herstellung von flùssigem roheisen oder stahlvorprodukten
AT382595B (de) * 1982-12-22 1987-03-10 Sueddeutsche Kalkstickstoff Anlage zur erzeugung von calciumcarbid
IN164687B (fr) * 1984-08-16 1989-05-13 Voest Alpine Ag
SE453304B (sv) * 1984-10-19 1988-01-25 Skf Steel Eng Ab Sett for framstellning av metaller och/eller generering av slagg fran oxidmalmer
AT381116B (de) * 1984-11-15 1986-08-25 Voest Alpine Ag Verfahren zur herstellung von fluessigem roheisen oder stahlvorprodukten sowie vorrichtung zur durchfuehrung des verfahrens
ZA85287B (en) * 1985-01-21 1986-09-24 Korf Engineering Gmbh Process for the production of pig iron
DE3535572A1 (de) * 1985-10-03 1987-04-16 Korf Engineering Gmbh Verfahren zur herstellung von roheisen aus feinerz
US4654076A (en) * 1986-01-30 1987-03-31 Plasma Energy Corporation Apparatus and method for treating metallic fines
DE3603894A1 (de) * 1986-02-05 1987-08-06 Korf Engineering Gmbh Verfahren zur herstellung von fluessigem roheisen oder stahlvormaterial
US4936908A (en) * 1987-09-25 1990-06-26 Nkk Corporation Method for smelting and reducing iron ores
DK158382C (da) * 1987-10-15 1990-10-22 Rockwool Int Fremgangsmaade ved fremstilling af en smelte til dannelse af mineraluld samt apparat til udoevelse af fremgangsmaaden
DE3742156C1 (de) * 1987-12-10 1988-10-13 Korf Engineering Gmbh Verfahren zum Betrieb eines Einschmelzvergasers und Einschmelzvergaser zu dessen Durchfuehrung
US6197088B1 (en) 1992-10-06 2001-03-06 Bechtel Group, Inc. Producing liquid iron having a low sulfur content
US5380352A (en) * 1992-10-06 1995-01-10 Bechtel Group, Inc. Method of using rubber tires in an iron making process
US5320676A (en) * 1992-10-06 1994-06-14 Bechtel Group, Inc. Low slag iron making process with injecting coolant
US5397376A (en) * 1992-10-06 1995-03-14 Bechtel Group, Inc. Method of providing fuel for an iron making process
US5338336A (en) * 1993-06-30 1994-08-16 Bechtel Group, Inc. Method of processing electric arc furnace dust and providing fuel for an iron making process
US5958107A (en) * 1993-12-15 1999-09-28 Bechtel Croup, Inc. Shift conversion for the preparation of reducing gas
AT404362B (de) * 1996-12-17 1998-11-25 Voest Alpine Ind Anlagen Verfahren und einschmelzvergaser zur herstellung von flüssigem metall
WO2014119612A1 (fr) * 2013-01-31 2014-08-07 住友重機械工業株式会社 Four de combustion à lit fluidisé et procédé d'utilisation de four de combustion à lit fluidisé

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD28565A (fr) *

Family Cites Families (10)

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Publication number Priority date Publication date Assignee Title
US2742352A (en) * 1952-03-05 1956-04-17 Exxon Research Engineering Co Ore reduction process
LU34613A1 (fr) * 1955-08-31
DE1246780B (de) 1955-08-31 1967-08-10 Werner Wenzel Dr Ing Verfahren zum Verhuetten von feinteiligen Erzen, insbesondere von Eisenerzen, mittels feinteiliger Reduktionskohle und elektrischer Beheizung
NL266640A (fr) 1960-08-01 1900-01-01
DE1950711A1 (de) 1968-10-15 1970-04-30 Ciba Geigy Neue Peptide und Verfahren zu ihrer Herstellung
GB1390351A (en) * 1971-02-16 1975-04-09 Tetronics Research Dev Co Ltd High temperature treatment of materials
DE2116445C3 (de) 1971-04-03 1973-09-13 Fried. Krupp Gmbh, 4300 Essen Verfahren zur Erzeugung von Stahl
GB1437261A (en) 1973-03-28 1976-05-26 Ransomes Sims & Jefferies Ltd Lawn mowers
SE395714B (sv) 1974-02-20 1977-08-22 Skf Ind Trading & Dev Sett och anordning for framstellning av metall ur oxidiskt material
SE387662B (sv) * 1974-02-20 1976-09-13 Skf Ind Trading & Dev Sett och anordning for smeltning av metall

Patent Citations (1)

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Publication number Priority date Publication date Assignee Title
DD28565A (fr) *

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Technische Mitteilungen, Band 70, Nr. 2, Februar 1977 W. MARNETTE et al. "Ausnutzung von Plasmawarme in der Metallurgie" seiten 89 bis 97 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013133748A1 (fr) * 2012-03-08 2013-09-12 Valeas Recycling Ab Procédé et équipement de réduction de fer
US9499872B2 (en) 2012-03-08 2016-11-22 Val'eas Recycling Solutions Ab Iron reduction process and equipment

Also Published As

Publication number Publication date
ES508210A0 (es) 1982-12-16
PL130491B1 (en) 1984-08-31
PL230508A1 (fr) 1981-12-23
ZA812222B (en) 1982-06-30
AU537907B2 (en) 1984-07-19
EP0037809B1 (fr) 1985-08-28
CA1160056A (fr) 1984-01-10
NO153144C (no) 1986-01-22
NO153144B (no) 1985-10-14
FI811014L (fi) 1981-10-04
FI68264C (fi) 1985-08-12
ES8302102A1 (es) 1982-12-16
AT367453B (de) 1982-07-12
ES8205266A1 (es) 1982-06-01
DD157915A5 (de) 1982-12-15
JPS56156708A (en) 1981-12-03
US4396421A (en) 1983-08-02
DE3171978D1 (en) 1985-10-03
FI68264B (fi) 1985-04-30
NO811138L (no) 1981-10-05
SU1118292A3 (ru) 1984-10-07
PH18456A (en) 1985-07-18
ATA182880A (de) 1981-11-15
ES501074A0 (es) 1982-06-01
AU6907181A (en) 1981-10-08
BR8102003A (pt) 1981-10-06

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