WO1999023264A1 - Verfahren und einrichtung zur steuerung der schaumschlackebildung in einem lichtbogenofen - Google Patents
Verfahren und einrichtung zur steuerung der schaumschlackebildung in einem lichtbogenofen Download PDFInfo
- Publication number
- WO1999023264A1 WO1999023264A1 PCT/DE1998/003062 DE9803062W WO9923264A1 WO 1999023264 A1 WO1999023264 A1 WO 1999023264A1 DE 9803062 W DE9803062 W DE 9803062W WO 9923264 A1 WO9923264 A1 WO 9923264A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- arc furnace
- carbon
- foam slag
- amount
- fed
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
-
- 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
- C21C5/5211—Manufacture of steel in electric furnaces in an alternating current [AC] electric arc furnace
- C21C5/5217—Manufacture of steel in electric furnaces in an alternating current [AC] electric arc furnace equipped with burners or devices for injecting gas, i.e. oxygen, or pulverulent materials into the furnace
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
- F27B3/28—Arrangement of controlling, monitoring, alarm or the like devices
-
- 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
- C21C5/28—Manufacture of steel in the converter
- C21C5/36—Processes yielding slags of special composition
- C21C2005/366—Foam slags
-
- 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
- C21C2300/00—Process aspects
- C21C2300/02—Foam creation
-
- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0025—Adding carbon material
-
- 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
- Y02P10/20—Recycling
Definitions
- the invention relates to a method and a device for controlling the foam slag formation in an arc furnace to which carbon is fed in such a way that both an at least partial encapsulation of the arc in the arc furnace takes place and an overdosed supply of carbon is avoided.
- Foam slag is created by foaming the slag in an arc furnace with carbon dioxide or carbon monoxide and serves to shield the radiation from the arc onto the furnace wall.
- Such an approach is e.g. known from DE 44 25 089 Cl or EP 0 637 834.
- the foam slag is controlled as a function of a measured sound emission in the range of twice the mains / supply frequency of the arc furnace.
- the carbon supply is increased when a switching level that can be predetermined by a control unit is exceeded and the carbon supply is reduced when the switching level is undershot.
- EP 0 637 834 the foam slag is regulated as a function of a measured noise emission and as a function of electrical variables.
- a disadvantage of the process according to DE 44 25 089 Cl or according to EP 0 637 834 is that the desired foam slag can be regulated only very slowly, and that conditions can occur for which the foam slag is disproportionately long is too low. In these cases, the power of the arc must be reduced, which increases the duration of the melting process. In an industrial large-scale melting process such as that used in an arc furnace is running, even a brief extension of the melting process is associated with high costs. Accordingly, it is an object of the invention to shorten the melting process in an arc furnace.
- the object is achieved by a method according to claim 1 or a device according to claim 8.
- the carbon is fed to the arc furnace in such a way that the arc is at least partially enveloped by foam slag in the arc furnace and an overdosed supply of carbon is avoided.
- the amount of carbon that is fed to the arc furnace is determined using a foam slag model depending on the amount of at least one of the feed materials scrap, steel, alloying agent or additives. Alloying agents can e.g. Carbon or metals such as manganese, nickel, etc. An additive is e.g. Lime.
- the determination of the amount of carbon that is supplied to the arc by means of a foam slag model depending on the amount of at least one of the feed materials scrap, steel, alloying agent or additives allows a desired foam slag level to be built up particularly quickly. In this way, it is possible to melt with a particularly high energy input, as a result of which the time required for melting the metal in the arc furnace is reduced.
- the amount of carbon is determined as a function of all essential coating materials, ie scrap, steel, the essential alloying agents and the essential additives.
- the combination of coating material rialien and energy supply allows a particularly precise prediction of the foam slag and the necessary carbon supply, whereby the desired foam slag level can be set particularly quickly and precisely.
- the foam slag model has a neural network.
- a neural network is particularly suitable for modeling the formation of foam slag, so that a particularly precise foam slag model is obtained by means of the neural network.
- FIG. 1 shows a three-phase arc furnace with a device for controlling the formation of foam slag
- FIG. 2 shows the functional interaction of the foam slag model and the arc furnace
- FIG. 1 shows an electric arc furnace 5, which in the exemplary embodiment is designed as a three-phase electric arc furnace, with a device for controlling the formation of foam slag 4 in the electric arc furnace 5.
- the electric arc furnace 5 three electrodes 1, 2, 3 are connected, which are connected via an adjustable transformer a three-phase power supply network 8 are connected, scrap melted so that liquid metal 6 accumulates in the lower part of the arc furnace 5.
- Arcs 9 form between the electrodes 1, 2, 3 and the scrap or the liquid metal 6.
- the arcs are enveloped by foam slag 4 in order to protect the walls of the arc furnace 5 from the energy radiation from the arcs 9.
- a device for controlling the foam slag is provided.
- this has a blow mold 10 and a computing device 11.
- the blow mold 10 blows carbon, in particular carbon mixed with air, into the arc furnace 5, in particular into the slag above the liquid metal 6.
- the carbon in the slag converts to carbon dioxide or carbon monoxide, so that foam slag 4 is formed.
- the amount of carbon to be injected is determined by the computing device 11 as a function of the electrical energy supplied to the arc furnace 5 and as a function of the quantity of charging materials in the arc furnace 5.
- Feed materials are essentially scrap, alloying agents and additives.
- An important additive is lime, for example, which forms an important component of the foam slag 4.
- the supply of electrical energy from the energy supply network 8 is regulated by means of the adjustable transformer 7 and / or by adjusting the height of the electrodes 1, 2, 3. Details of an advantageous regulation of the energy supply in connection with the invention can be found in DE 197 11 453, EP 0 036 122 and DE 44 15 727.
- the energy supply, in particular the height of the electrodes 1, 2 and 3, is set as a function of the level of the foam slag 4 in the electric arc furnace 5.
- the computing device 11 determines in a particularly advantageous manner by means of the foam slag model implemented on it, in addition to the target value for the supply of carbon, the current level of the level of the foam slag 4 in the electric arc furnace 5.
- the regulation of the transformer 7 and the regulation of the height of the electrodes 1 , 2, 3 can also be implemented on the computing device 11 in an exemplary embodiment.
- FIG. 1 shows, in an exemplary embodiment, an arc furnace 5 designed as a three-phase arc furnace.
- the invention can also be used particularly advantageously for a direct current arc furnace.
- the method according to the invention is particularly superior to the method according to DE 44 25 089 Cl and EP 0 637 834, since the significant frequencies m der
- Noise emission or m the electrical sizes are not or only weakly present.
- FIG. 2 shows the interaction of a foam slag model 25 with an electric arc furnace 5.
- the essential processes that take place in the electric arc furnace 5 are the charging 22 of the electric arc furnace 5, the melting process 23 in the electric arc furnace 5 and the tapping 24 of the electric arc furnace 5, in which the liquid metal is tapped in the arc furnace 5.
- the arc furnace 5 is loaded with a certain amount of feed materials 27 such as scrap, steel, alloying agents and / or additives.
- Energy 28 is supplied to the arc furnace 5 during the melting process 23.
- Carbon 29 m is also blown into the arc furnace 5.
- a foam slag model 25 determines setpoints for the supply of carbon 29 m from the arc furnace 5 from the quantity of the feed materials 27 and the supply of energy 28.
- the foam slag model 25 is optimized so that it supplies the arc furnace 5 with particularly precise target values for the supply of carbon 29 m.
- the properties 30 of foam slag which is present in the arc furnace 5 during tapping 24, are fed to an evaluator 26.
- the evaluator 26 has a learning algorithm that determines new parameters 20 for the foam slag model 25. New parameters 20 are preferably determined as a function of the properties 30 of the foam slag and the properties 19 of the foam slag determined by the foam slag part 25.
- the properties of the foam slag are e.g. determined by an operator and entered the evaluator 26 via a human-machine interface.
- the neural network has three input nodes 31, 32, 33, the neural network via the input node 31 information about the amount of scrap in the electric arc furnace, via the input node 32 information about the amount of energy supplied and via the input node 33 information about the supplied Amount of lime to be fed.
- the neural network has a level with hidden neurons 34, 35 and 36 and an output node 37, via which a setpoint for the carbon supply is output.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
Abstract
Description
Claims
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP98958815A EP1027462A1 (de) | 1997-10-31 | 1998-10-19 | Verfahren und einrichtung zur steuerung der schaumschlackebildung in einem lichtbogenofen |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1997148310 DE19748310C1 (de) | 1997-10-31 | 1997-10-31 | Verfahren und Einrichtung zur Steuerung der Schaumschlackenbildung in einem Lichtbogenofen |
DE19748310.0 | 1997-10-31 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1999023264A1 true WO1999023264A1 (de) | 1999-05-14 |
Family
ID=7847314
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE1998/003062 WO1999023264A1 (de) | 1997-10-31 | 1998-10-19 | Verfahren und einrichtung zur steuerung der schaumschlackebildung in einem lichtbogenofen |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP1027462A1 (de) |
DE (1) | DE19748310C1 (de) |
WO (1) | WO1999023264A1 (de) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6544314B2 (en) | 2000-03-17 | 2003-04-08 | Specialty Minerals (Michigan) Inc. | Process and apparatus for automatically controlling slag foaming |
WO2007087979A1 (de) * | 2006-02-01 | 2007-08-09 | Sms Demag Ag | Verfahren zur erzeugung einer schaumschlacke in einer metallischen schmelze |
US7634451B2 (en) | 2003-02-13 | 2009-12-15 | Siemens Aktiengesellschaft | Multivariate, predictive regulation of a direct reduction process |
US8133296B2 (en) | 2007-10-23 | 2012-03-13 | Sms Siemag Aktiengesellschaft | Process for producing stainless steel using direct reduction furnaces for ferrochrome and ferronickel on the primary side of a converter |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19801295B4 (de) * | 1998-01-16 | 2007-06-06 | Siemens Ag | Einrichtung zur Regelung eines Lichtbogenofens |
DE19925144C2 (de) * | 1999-06-02 | 2001-04-19 | Metallgesellschaft Ag | Verfahren zur Herstellung von Schaumschlacke |
LU90788B1 (fr) * | 2001-06-13 | 2002-12-16 | Wurth Paul Sa | Procédé de production de fonte liquide dans un four électrique |
JP2009503419A (ja) * | 2005-07-22 | 2009-01-29 | シーメンス アクチエンゲゼルシヤフト | アーク炉の状態量を算定するための方法とアーク炉 |
DE102005034409B3 (de) * | 2005-07-22 | 2006-05-24 | Siemens Ag | Verfahren zur Bestimmung mindestens einer Zustandsgröße eines Elektrolichtbogenofens und Elektrolichtbogenofen |
EP2394124B1 (de) * | 2009-02-03 | 2017-10-25 | Primetals Technologies Germany GmbH | Verfahren zur regelung eines kohlenmonoxid-ausstosses eines elektrolichtbogenofens |
CN102506593A (zh) * | 2011-11-03 | 2012-06-20 | 云南新立有色金属有限公司 | 一种全密闭直流电弧炉泡沫渣检测的方法 |
Citations (8)
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DD228831A1 (de) * | 1984-10-26 | 1985-10-23 | Brandenburg Stahl Walzwerk | Verfahren zur einhuellung des lichtbogens |
US4564388A (en) * | 1984-08-02 | 1986-01-14 | Intersteel Technology, Inc. | Method for continuous steelmaking |
SU1370150A1 (ru) * | 1985-12-26 | 1988-01-30 | Центральный научно-исследовательский институт черной металлургии им.И.П.Бардина | Способ выплавки стали |
EP0545379A1 (de) * | 1991-12-03 | 1993-06-09 | Praxair Technology, Inc. | Verfahren zum Entkohlen einer Stahlschmelze mit Hilfe neuronaler Netzwerke |
EP0637634A1 (de) * | 1993-08-04 | 1995-02-08 | Voest-Alpine Industrieanlagenbau Gmbh | Verfahren zum Herstellen einer Metallschmelze |
US5406581A (en) * | 1991-04-15 | 1995-04-11 | Milltech-Hoh, Inc. | Control system for electric arc furnace |
BE1007960A6 (fr) * | 1994-01-13 | 1995-11-28 | Centre Rech Metallurgique | Procede d'elaboration d'acier dans un four a arc. |
JPH08176639A (ja) * | 1994-12-28 | 1996-07-09 | Nkk Corp | アーク炉製鋼法 |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
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DE4425089C1 (de) * | 1994-07-15 | 1996-01-11 | Hamburger Stahlwerke Gmbh | Verfahren zur Steuerung der Schaumschlackebildung im Drehstromlichtbogenofen |
-
1997
- 1997-10-31 DE DE1997148310 patent/DE19748310C1/de not_active Expired - Fee Related
-
1998
- 1998-10-19 EP EP98958815A patent/EP1027462A1/de not_active Ceased
- 1998-10-19 WO PCT/DE1998/003062 patent/WO1999023264A1/de not_active Application Discontinuation
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
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US4564388A (en) * | 1984-08-02 | 1986-01-14 | Intersteel Technology, Inc. | Method for continuous steelmaking |
DD228831A1 (de) * | 1984-10-26 | 1985-10-23 | Brandenburg Stahl Walzwerk | Verfahren zur einhuellung des lichtbogens |
SU1370150A1 (ru) * | 1985-12-26 | 1988-01-30 | Центральный научно-исследовательский институт черной металлургии им.И.П.Бардина | Способ выплавки стали |
US5406581A (en) * | 1991-04-15 | 1995-04-11 | Milltech-Hoh, Inc. | Control system for electric arc furnace |
EP0545379A1 (de) * | 1991-12-03 | 1993-06-09 | Praxair Technology, Inc. | Verfahren zum Entkohlen einer Stahlschmelze mit Hilfe neuronaler Netzwerke |
EP0637634A1 (de) * | 1993-08-04 | 1995-02-08 | Voest-Alpine Industrieanlagenbau Gmbh | Verfahren zum Herstellen einer Metallschmelze |
BE1007960A6 (fr) * | 1994-01-13 | 1995-11-28 | Centre Rech Metallurgique | Procede d'elaboration d'acier dans un four a arc. |
JPH08176639A (ja) * | 1994-12-28 | 1996-07-09 | Nkk Corp | アーク炉製鋼法 |
Non-Patent Citations (2)
Title |
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DATABASE WPI Section Ch Week 8833, Derwent World Patents Index; Class M24, AN 88-233868, XP002095503 * |
DATABASE WPI Section Ch Week 9637, Derwent World Patents Index; Class M24, AN 96-368597, XP002095504 * |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6544314B2 (en) | 2000-03-17 | 2003-04-08 | Specialty Minerals (Michigan) Inc. | Process and apparatus for automatically controlling slag foaming |
US7634451B2 (en) | 2003-02-13 | 2009-12-15 | Siemens Aktiengesellschaft | Multivariate, predictive regulation of a direct reduction process |
WO2007087979A1 (de) * | 2006-02-01 | 2007-08-09 | Sms Demag Ag | Verfahren zur erzeugung einer schaumschlacke in einer metallischen schmelze |
AU2007211649B2 (en) * | 2006-02-01 | 2011-06-09 | Sms Siemag Aktiengesellschaft | Method for the production of a foamed slag in a metal bath |
US8043402B2 (en) | 2006-02-01 | 2011-10-25 | Sms Siemag Aktiengesellschaft | Method for the production of a foamed slag in a metal bath |
US8133296B2 (en) | 2007-10-23 | 2012-03-13 | Sms Siemag Aktiengesellschaft | Process for producing stainless steel using direct reduction furnaces for ferrochrome and ferronickel on the primary side of a converter |
Also Published As
Publication number | Publication date |
---|---|
DE19748310C1 (de) | 1998-12-17 |
EP1027462A1 (de) | 2000-08-16 |
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