EP0071755A1 - Method of preheating and heating empty AOD converter vessels - Google Patents

Method of preheating and heating empty AOD converter vessels Download PDF

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Publication number
EP0071755A1
EP0071755A1 EP82105900A EP82105900A EP0071755A1 EP 0071755 A1 EP0071755 A1 EP 0071755A1 EP 82105900 A EP82105900 A EP 82105900A EP 82105900 A EP82105900 A EP 82105900A EP 0071755 A1 EP0071755 A1 EP 0071755A1
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EP
European Patent Office
Prior art keywords
aod
oxygen
nozzle
converter
fuel
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.)
Withdrawn
Application number
EP82105900A
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German (de)
French (fr)
Inventor
Gerhard Dr. c/o MG Burdett Gas Prod. Comp. Gross
Marijan Velikonja
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Messer Griesheim GmbH
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Messer Griesheim GmbH
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Filing date
Publication date
Application filed by Messer Griesheim GmbH filed Critical Messer Griesheim GmbH
Publication of EP0071755A1 publication Critical patent/EP0071755A1/en
Withdrawn legal-status Critical Current

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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
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/068—Decarburising
    • 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
    • C21C5/005—Manufacture of stainless steel
    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/48—Bottoms or tuyéres of converters
    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/44—Refractory linings
    • C21C5/445—Lining or repairing the taphole
    • C21C2005/446—Dry linings

Definitions

  • the invention relates to a method for preheating and heating empty AOD converters with a fuel-oxygen flame.
  • AOD converters are used to freshen stainless steel melts with mixtures of argon or nitrogen and oxygen. They essentially consist of the bricked-up converter vessel, in which one or more AOD nozzles are permanently installed above the floor, e.g. is known from DE-OS 2 065 105.
  • the AOD nozzle consists of an injection nozzle for blowing in the process gas containing oxygen. To avoid melting of the injection nozzle, it is surrounded by an annular nozzle, from which a jet of nitrogen or argon is emitted emerges as a protective gas at high speed.
  • a jet of nitrogen or argon is emitted emerges as a protective gas at high speed.
  • the lining of the converter In order to prevent the heat exchange between the melt and the colder lining, the lining of the converter must be preheated to a high temperature before filling, which is close to the temperature of the liquid melt. Such a high wall temperature can only be achieved economically with an oxygen flame. For this purpose, it is known to insert a fuel-oxygen burner into the converter opening from above and to remove it again before filling the converter.
  • the invention is therefore based on the object of providing a method for preheating and heating up empty AOD converters, which retains the advantages of the fuel-oxygen flame as a heat source without, however, requiring its own fuel-oxygen burner.
  • the fuel gas is preferably introduced through the injection nozzle for the process gas and the oxygen through the ring nozzle for the protective gas into the AOD converter.
  • additional fuel gas-oxygen nozzles corresponding to the AOD nozzles can also be installed in the converter wall above the bath level which forms in the filled converter.
  • ignition electrodes are installed centrally in the nozzles used to form the fuel gas-oxygen flames.
  • Both liquid gas and fuel gas can be used as fuel. Oil is not suitable as a fuel for safety reasons, since it cannot be completely removed by nitrogen flushing before and after the burner is used, and therefore a reaction with the process gas oxygen can occur.
  • a and 2 show the brick AOD converter 1, which is equipped with two AOD nozzles 2 and 3.
  • the process gas supply from argon and oxygen takes place through the line 5 provided with a valve 4 into the injection nozzle 6.
  • the protective gas nitrogen passes through the line 8 provided with a valve 7 into the ring nozzle 9.
  • a line 10 is provided with a valve 10 Line 11 connected through which fuel gas can be supplied.
  • a line 13 provided with a valve 12 is connected to the line 8 and serves to supply oxygen.
  • the AOD nozzle 3 has the same gas connections, but which are not shown in the drawing.
  • the valves 4, 7, 10 and 12 are automatic control valves which are controlled as a function of flow meters arranged in the lines. As is known, these details are not shown.
  • the empty AOD converter 1 is preheated and heated by fuel gas-oxygen flames 14, which are formed according to the invention by means of the AOD nozzles 2 and 3. This is described using the example of the AOD nozzle 2.
  • valves 4 and 7 closed and valves 10 and 12 open, fuel gas and oxygen flow into the AOD nozzle 2.
  • the oxygen is blown in through the concentric ring nozzle 9. Due to the small gap width of the concentric ring nozzle 9, the oxygen emerges at the speed of sound.
  • the expanding oxygen jet provides additional cooling at the nozzle outlet.
  • the high turbulent mixing results in a short externally mixing fuel gas-oxygen flame 14 which does not touch the opposite converter wall.
  • a reversal of the procedure is also possible.
  • the fuel gas is injected through the concentric ring nozzle 9 and the oxygen through the central injection nozzle 6.
  • the advantage of this arrangement is less expenditure on equipment, since the inerting of the oxygen and fuel gas lines can be dispensed with. Due to unstable burner behavior, however, the maximum possible burner output is reduced by 50%.
  • a fuel gas-oxygen nozzle 15 is additionally inserted, which is constructed in accordance with the AOD nozzles 2 and 3, but only has connections for fuel gas 16 and oxygen 17.
  • Several such fuel gas-oxygen nozzles 15 can also be installed in the converter wall. They are only necessary if the power of the fuel gas-oxygen flames 14 is too low. They are expediently arranged above the bath level which forms in the filled AOD converter. The advantage of this design is that these nozzles cannot be attacked by any process burn-off.
  • the wall temperature is measured via a built-in thermocouple 18 and regulated to the setpoint value by a temperature controller 19.
  • the burner output can be considerably reduced with fixed flow rates of fuel gas with oxygen.
  • the actual value of the amount of oxygen and the amount of fuel gas is therefore at constant admission pressures measured by the flow meter and controlled by the automatic control valves 4 and 7 to the specified setpoint.
  • FIG. 3 shows an AOD nozzle which is particularly suitable for the method according to the invention since it enables the fuel-oxygen mixture to be ignited when the AOD converter 1 is cold by an ignition electrode 24 integrated in the AOD nozzle.
  • the AOD nozzle initially consists of known parts, namely an inner tube 20 with connecting piece 21 for the supply of process gas or fuel gas, and an outer tube 22 with connection 23 for the supply of protective gas or oxygen.
  • an ignition electrode 24 with a square neck rod 25 ceramic insulation 26 and protective tube 27 is installed centrally in the inner tube 20.
  • the guide in the inner tube is carried out by webs 28, the attachment to the outer tube 22 by the connecting cylinder 29, screw insert 30 and lock nut 31.
  • the annular cross section that forms between the inner tube 20 and the protective tube 27 corresponds to the original cross section of the injection nozzle of the inner tube.
  • the kanthal rod 25 is bent at a right angle at the end and is flush with the ceramic insulation 26.
  • the ignition electrode can be pulled back by the screw insert 30 for replacement.
  • the flame is monitored by a UV probe, which is installed in a cooled protective tube above the converter opening in the exhaust hood.

Abstract

Particularly in small AOD converters (1), it is almost indispensable to preheat their brick lining almost up to the bath temperature of the molten steel, before they are filled with melt. Otherwise, the temperature losses are excessive. Appropriate temperatures can be reached only by means of fuel/oxygen burners. For this purpose, the burner must be positioned above or in the converter opening. Because of the high exit gas temperatures, water-cooled burners are used in most cases. After heating, the burner is swivelled away from the converter opening. The burner represents additional expense. To avoid this, at least one of the AOD nozzles (2) located above the converter bottom is used during heating-up for forming the fuel/oxygen flame (14). <IMAGE>

Description

Die Erfindung betrifft ein Verfahren zum Vorwärmen und Aufheizen von leeren AOD-Konvertern mit einer Brennstoff-Sauerstoff-Flamme.The invention relates to a method for preheating and heating empty AOD converters with a fuel-oxygen flame.

AOD-Konverter dienen zum Frischen von Edelstahlschmelzen mit Gemischen aus Argon bzw. Stickstoff und Sauerstoff. Sie bestehen im wesentlichen aus dem ausgemauerten Konvertergefäß, in welchem oberhalb des Bodens eine oder mehrere AOD-Düsen fest eingebaut sind, wie z.B. aus der DE-OS 2 065 105 bekannt ist.AOD converters are used to freshen stainless steel melts with mixtures of argon or nitrogen and oxygen. They essentially consist of the bricked-up converter vessel, in which one or more AOD nozzles are permanently installed above the floor, e.g. is known from DE-OS 2 065 105.

Die AOD-Düse besteht aus einer Einblasdüse zum Einblasen des Sauerstoff enthaltenden Prozeßgases. Um das Abschmelzen der Einblasdüse zu vermeiden, ist sie von einer Ringdüse umgeben, aus der ein Stickstoff- oder Argonstrahl als Schutzgas mit hoher Geschwindigkeit austritt. Beim Einfüllen der Edelstahlschmelze in einen kalten Konverter sinkt die Temperatur der Edelstahlschmelze durch den Wärmeaustausch mit der kalten Konverterausmauerung erheblich ab. Naturgemäß ist diese Temperaturabsenkung bei kleinen Konvertern besonders stark. Der Temperaturverlust wird durch Zugabe von Silizium und Aluminium zur Schmelze ausgeglichen. Die Oxyidationsprodukte führen allerdings zu einem erhöhten Verschleiß der Ausmauerung.The AOD nozzle consists of an injection nozzle for blowing in the process gas containing oxygen. To avoid melting of the injection nozzle, it is surrounded by an annular nozzle, from which a jet of nitrogen or argon is emitted emerges as a protective gas at high speed. When the stainless steel melt is poured into a cold converter, the temperature of the stainless steel melt drops considerably as a result of the heat exchange with the cold converter lining. Naturally, this reduction in temperature is particularly strong in the case of small converters. The temperature loss is compensated for by adding silicon and aluminum to the melt. However, the oxidation products lead to increased wear of the lining.

Um den Wärmeaustausch zwischen der Schmelze und der kälteren Ausmauerung zu verhindern, muß vor dem Befüllen die Ausmauerung des Konverters auf eine hohe Temperatur vorgeheizt werden, die der Temperatur der flüssigen Schmelze nahe kommt. Eine so hohe Wandtemperatur kann wirtschaftlich nur durch eine Sauerstoffflamme realisiert werden. Hierzu ist es bekannt, einen Brennstoff-Sauerstoff-Brenner von oben in die Konverteröffnung einzufahren und vor dem Befüllen des Konverters wieder zu entfernen.In order to prevent the heat exchange between the melt and the colder lining, the lining of the converter must be preheated to a high temperature before filling, which is close to the temperature of the liquid melt. Such a high wall temperature can only be achieved economically with an oxygen flame. For this purpose, it is known to insert a fuel-oxygen burner into the converter opening from above and to remove it again before filling the converter.

Wegen der hohen Abgastemperaturen werden meistens wassergekühlte Brenner benutzt. Sowohl die Installation als auch die Handhabung des Brennstoff-Sauerstoff-Brenners verursachen Kosten.Because of the high exhaust gas temperatures, water-cooled burners are mostly used. Both the installation and the handling of the fuel-oxygen burner incur costs.

Der Erfindung liegt daher die Aufgabe zugrunde, ein Verfahren zum Vorwärmen und Aufheizen von leeren AOD-Konvertern zu schaffen, welches die Vorteile der Brennstoff-Sauerstoff-Flamme als Wärmequelle beibehält ohne jedoch einen eigenen Brennstoff-Sauerstoff-Brenner zu benötigen.The invention is therefore based on the object of providing a method for preheating and heating up empty AOD converters, which retains the advantages of the fuel-oxygen flame as a heat source without, however, requiring its own fuel-oxygen burner.

Bei einem Verfahren zum Vorwärmen und Aufheizen von leeren AOD-Konvertern, in denen oberhalb des Konverterbodens zumindest eine AOD-Düse, bestehend aus einer Einblasdüse zum Einblasen eines Prozeßgases und einer diese umgebenden Ringdüse zum Einblasen eines Schutzgases, fest eingebaut ist, mit einer Brennstoff-Sauerstoff-Flamme, wird dies gemäß der Erfindung dadurch erreicht, daß die Brennstoff-Sauerstoff-Flamme mittels der AOD-Düse gebildet wird, indem dieser bei unterbrochener Zufuhr des Prozeßgases und des Schutzgases Brenngas und Sauerstoff zugeführt werden.In a method for preheating and heating up empty AOD converters, in which above the converter base at least one AOD nozzle, consisting of an injection nozzle for blowing in a process gas and a surrounding one Annular nozzle for blowing in a protective gas, permanently installed, with a fuel-oxygen flame, this is achieved according to the invention in that the fuel-oxygen flame is formed by means of the AOD nozzle, in that the process gas and the supply are interrupted Shielding gas, fuel gas and oxygen are supplied.

Bevorzugt wird das Brenngas durch die Einblasdüse für das Prozeßgas und der Sauerstoff durch die Ringdüse für das Schutzgas in den AOD-Konverter eingeführt.The fuel gas is preferably introduced through the injection nozzle for the process gas and the oxygen through the ring nozzle for the protective gas into the AOD converter.

Bei Bedarf, d.h. zu geringer Wärmeerzeugung können oberhalb des sich im gefüllten Konverter ausbildenden Badspiegels weitere, den AOD-Düsen entsprechende Brenngas-Sauerstoff-Düsen in die Konverterwand zusätzlich eingebaut werden.If necessary, i.e. if the heat generation is too low, additional fuel gas-oxygen nozzles corresponding to the AOD nozzles can also be installed in the converter wall above the bath level which forms in the filled converter.

Es ist vorteilhaft, wenn in den zur Bildung der Brenngas-Sauerstoff-Flammen dienenden Düsen Zündelektroden zentrisch eingebaut sind. Als Brennstoff kann sowohl Flüssiggas als auch Brenngas verwendet werden. öl ist als Brennstoff aus Sicherheitsgründen nicht geeignet, da dieses durch die Stickstoffspülung vor und nach dem Brennereinsatz nicht vollständig entfernt werden kann, und deshalb eine Reaktion mit dem Prozeßgassauerstoff eintreten kann.It is advantageous if ignition electrodes are installed centrally in the nozzles used to form the fuel gas-oxygen flames. Both liquid gas and fuel gas can be used as fuel. Oil is not suitable as a fuel for safety reasons, since it cannot be completely removed by nitrogen flushing before and after the burner is used, and therefore a reaction with the process gas oxygen can occur.

Die Zeichnungen veranschaulichen ein Ausführungsbeispiel der Erfindung.The drawings illustrate an embodiment of the invention.

Es zeigen:

  • Fig.1 einen AOD-Konverter mit AOD-Düse und Zusatzdüse im Längsschnitt,
  • Fig.2 einen Querschnitt in Höhe der AOD-Düsen durch den AOD-Konverter von Fig.1,
  • Fig.3 eine AOD-Düse mit zentrisch angeordneter Zündelektrode.
Show it:
  • 1 shows an AOD converter with AOD nozzle and additional nozzle in longitudinal section,
  • 2 shows a cross section at the level of the AOD nozzles through the AOD converter from FIG. 1,
  • 3 shows an AOD nozzle with a centrally arranged ignition electrode.

Die Fig.1 und 2 zeigen den gemauerten AOD-Konverter 1, der mit zwei AOD-Düsen 2 und 3 ausgestattet ist. Die Prozeßgaszufuhr aus Argon und Sauerstoff erfolgt durch die mit einem Ventil 4 versehene Leitung 5 in die Einblasdüse 6. Das Schutzgas Stickstoff gelangt durch die mit einem Ventil 7 versehene Leitung 8 in die Ringdüse 9. An die Leitung 5 ist eine mit einem Ventil 10 versehene Leitung 11 angeschlossen, durch welche Brenngas zugeführt werden kann. Entsprechend ist an die Leitung 8 eine mit einem Ventil 12 versehene Leitung 13 angeschlossen, welche der Zufuhr von Sauerstoff dient. Die AOD-Düse 3 besitzt die gleichen Gasanschlüsse, die aber in der Zeichnung nicht dargestellt sind. Die Ventile 4,7,10 und 12 sind automatische Regelventile, die in Abhängigkeit von in den Leitungen angeordneten Strömungsmessern geregelt werden. Diese Einzelheiten sind, da bekannt, nicht dargestellt.1 and 2 show the brick AOD converter 1, which is equipped with two AOD nozzles 2 and 3. The process gas supply from argon and oxygen takes place through the line 5 provided with a valve 4 into the injection nozzle 6. The protective gas nitrogen passes through the line 8 provided with a valve 7 into the ring nozzle 9. A line 10 is provided with a valve 10 Line 11 connected through which fuel gas can be supplied. Correspondingly, a line 13 provided with a valve 12 is connected to the line 8 and serves to supply oxygen. The AOD nozzle 3 has the same gas connections, but which are not shown in the drawing. The valves 4, 7, 10 and 12 are automatic control valves which are controlled as a function of flow meters arranged in the lines. As is known, these details are not shown.

Der leere AOD-Konverter 1 wird vorgewärmt und aufgeheizt durch Brenngas-Sauerstoff-Flammen 14, die erfindungsgemäß mittels der AOD-Düsen 2 und 3 gebildet werden. Dies wird am Beispiel der AOD-Düse 2 beschrieben. Bei geschlossenen Ventilen 4 und 7 und geöffneten Ventilen 10 und 12 strömen in die AOD-Düse 2 Brenngas und Sauerstoff. Der Sauerstoff wird durch die konzentrische Ringdüse 9 eingeblasen. Durch die geringe Spaltweite der konzentrischen Ringdüse 9 tritt der Sauerstoff mit Schallgeschwindigkeit aus. Der expandierende Sauerstoffstrahl bewirkt eine zusätzliche Kühlung am Düsenaustritt.The empty AOD converter 1 is preheated and heated by fuel gas-oxygen flames 14, which are formed according to the invention by means of the AOD nozzles 2 and 3. This is described using the example of the AOD nozzle 2. With valves 4 and 7 closed and valves 10 and 12 open, fuel gas and oxygen flow into the AOD nozzle 2. The oxygen is blown in through the concentric ring nozzle 9. Due to the small gap width of the concentric ring nozzle 9, the oxygen emerges at the speed of sound. The expanding oxygen jet provides additional cooling at the nozzle outlet.

Durch die hohe turbulente Vermischung entsteht eine kurze außenmischende Brenngas-Sauerstoff-Flamme 14, die die gegenüberliegende Konverterwand nicht berührt.The high turbulent mixing results in a short externally mixing fuel gas-oxygen flame 14 which does not touch the opposite converter wall.

Eine Umkehrung der Verfahrensweise ist ebenfalls möglich. Das Brenngas wird dabei durch die konzentrische Ringdüse 9 und der Sauerstoff durch die zentrische Einblasdüse 6 eingeblasen. Der Vorteil dieser Anordnung ist ein geringerer apparativer Aufwand, da die Inertisierung der Sauerstoff- und Brenngasleitung entfallen kann. Infolge instabilen Brennerverhaltens vermindert sich jedoch die maximal mögliche Brennerleistung um 50%.A reversal of the procedure is also possible. The fuel gas is injected through the concentric ring nozzle 9 and the oxygen through the central injection nozzle 6. The advantage of this arrangement is less expenditure on equipment, since the inerting of the oxygen and fuel gas lines can be dispensed with. Due to unstable burner behavior, however, the maximum possible burner output is reduced by 50%.

In die Wand des AOD-Konverters 1 ist zusätzlich eine Brenngas-Sauerstoff-Düse 15 eingesetzt, die entsprechend den AOD-Düsen 2 und 3 aufgebaut ist, aber nur Anschlüsse für Brenngas 16 und Sauerstoff 17 besitzt. Es können auch mehrere derartige Brenngas-Sauerstoff-Düsen 15 in die Konverterwand eingebaut werden.Sie sind nur dann erforderlich, wenn die Leistung der Brenngas-Sauerstoff-Flammen 14 zu gering sein sollte. Sie werden zweckmäßig oberhalb des sich im gefüllten AOD-Konverter ausbildenden Badspiegels angeordnet. Der Vorteil dieser Bauweise ist, daß diese Düsen durch einen eventuellen Prozeßabbrand nicht angegriffen werden können.In the wall of the AOD converter 1, a fuel gas-oxygen nozzle 15 is additionally inserted, which is constructed in accordance with the AOD nozzles 2 and 3, but only has connections for fuel gas 16 and oxygen 17. Several such fuel gas-oxygen nozzles 15 can also be installed in the converter wall. They are only necessary if the power of the fuel gas-oxygen flames 14 is too low. They are expediently arranged above the bath level which forms in the filled AOD converter. The advantage of this design is that these nozzles cannot be attacked by any process burn-off.

Die Wandtemperatur wird über ein eingebautes Thermoelement 18 gemessen und mit einem Temperaturregler 19 auf den eingestellten Sollwert geregelt.The wall temperature is measured via a built-in thermocouple 18 and regulated to the setpoint value by a temperature controller 19.

Infolge von möglichen Querschnittsverengungen durch einen Bärenansatz an der Ringdüse 9 kann die Brennerleistung bei fest eingestellten Durchflußmengen von Brenngas mit Sauerstoff erheblich vermindert werden. Der Istwert der Sauerstoffmenge und der Brenngasmenge wird deshalb bei konstanten Vordrücken durch Strömungsmesser gemessen und durch die automatischen Regelventile 4 und 7 auf den vorgegebenen Sollwert geregelt.As a result of possible cross-sectional constrictions due to a bear attachment on the ring nozzle 9, the burner output can be considerably reduced with fixed flow rates of fuel gas with oxygen. The actual value of the amount of oxygen and the amount of fuel gas is therefore at constant admission pressures measured by the flow meter and controlled by the automatic control valves 4 and 7 to the specified setpoint.

Fig.3 zeigt eine für das erfindungsgemäße Verfahren besonders geeignete AOD-Düse da sie die Zündung des Brennstoff-Sauerstoff-Gemisches im kalten Zustand des AOD-Konverters 1 durch eine in die AOD-Düse integrierte Zündelektrode 24 ermöglicht.FIG. 3 shows an AOD nozzle which is particularly suitable for the method according to the invention since it enables the fuel-oxygen mixture to be ignited when the AOD converter 1 is cold by an ignition electrode 24 integrated in the AOD nozzle.

Die AOD-Düse besteht zunächst aus bekannten Teilen, nämlich einem Innenrohr 20 mit Anschlußstutzen 21 zur Zufuhr von Prozeßgas bzw. Brenngas, sowie einem Außenrohr 22 mit Anschluß 23 zur Zufuhr von Schutzgas bzw. Sauerstoff. Zusätzlich ist erfindungsgemäß eine Zündelektrode 24 mit Kanthalstab 25, keramischer Isolierung 26 und Schutzrohr 27 zentrisch in das Innenrohr 20 eingebaut. Die Führung im Innenrohr erfolgt durch Stege 28, die Befestigung am Außenrohr 22 durch den Anschlußzylinder 29, Schraubeinsatz 30 und Kontermutter 31. Der sich bildende ringförmige Querschnitt zwischen Innenrohr 20 und Schutzrohr 27 entspricht dabei dem ursprünglichen Querschnitt der Einblasdüse des inneren Rohres. Der Kanthalstab 25 ist am Ende rechtwinklig umgebogen und ist bündig mit der keramischen Isolierung 26. Die Zündelektrode kann durch den Schraubeinsatz 30 zum Auswechseln nach hinten herangezogen werden.The AOD nozzle initially consists of known parts, namely an inner tube 20 with connecting piece 21 for the supply of process gas or fuel gas, and an outer tube 22 with connection 23 for the supply of protective gas or oxygen. In addition, according to the invention, an ignition electrode 24 with a square neck rod 25, ceramic insulation 26 and protective tube 27 is installed centrally in the inner tube 20. The guide in the inner tube is carried out by webs 28, the attachment to the outer tube 22 by the connecting cylinder 29, screw insert 30 and lock nut 31. The annular cross section that forms between the inner tube 20 and the protective tube 27 corresponds to the original cross section of the injection nozzle of the inner tube. The kanthal rod 25 is bent at a right angle at the end and is flush with the ceramic insulation 26. The ignition electrode can be pulled back by the screw insert 30 for replacement.

Bei der Zündung des Brenngas-Sauerstoff-Gemisches wird die innere Ringdüse vorzugsweise von Brenngas und die äußere von Sauerstoff durchströmt.When the fuel gas-oxygen mixture is ignited, fuel gas flows through the inner ring nozzle and oxygen flows through the outer ring nozzle.

Die Flammenüberwachung erfolgt durch eine UV-Sonde, die oberhalb der Konverteröffnung in der Absaughaube in einem gekühlten Schutzrohr eingebaut ist.The flame is monitored by a UV probe, which is installed in a cooled protective tube above the converter opening in the exhaust hood.

Claims (4)

1. Verfahren zum Vorwärmen und Aufheizen von leeren AOD-Konvertern (1), in denen oberhalb des Konverterbodens zumindest eine AOD-Düse (2,3),bestehend aus einer Einblasdüse (6) zum Einblasen eines Prozeßgases und einer diese umgebenden Ringdüse (9) zum Einblasen eines Schutzgases, fest eingebaut ist, mit einer Brennstoff-Sauerstoff-Flamme,
dadurch gekennzeichnet,
daß die Brennstoff-Sauerstoff-Flamme (14) mittels der AOD-Düse (2) gebildet wird, indem dieser bei unterbrochener Zufuhr des Prozeßgases und des Schutzgases Brenngas und Sauerstoff zugeführt werden.1. A method for preheating and heating up empty AOD converters (1), in which at least one AOD nozzle (2, 3), above the converter base, consists of an injection nozzle (6) for blowing in a process gas and an annular nozzle surrounding it (9 ) for blowing in a protective gas, permanently installed, with a fuel-oxygen flame,
characterized,
that the fuel-oxygen flame (14) is formed by means of the AOD nozzle (2) by supplying fuel gas and oxygen when the process gas and the protective gas are interrupted. 2. Verfahren nach Anspruch 1,
dadurch gekennzeichnet,
daß das Brenngas durch die Einblasdüse (6) für das Prozeßgas und der Sauerstoff durch die Ringdüse (9) für das Schutzgas in den AOD-Konverter eingeführt werden.2. The method according to claim 1,
characterized,
that the fuel gas through the injection nozzle (6) for the process gas and the oxygen through the ring nozzle (9) for the protective gas are introduced into the AOD converter. 3. Vorrichtung zur Durchführung des Verfahrens nach Anspruch 1 oder 2,
dadurch gekennzeichnet,
daß oberhalb der sich im gefüllten AOD-Konverter ausbildenden Badspiegels zumindest eine den AOD-Düsen entsprechende Brenngas-Sauerstoff-Düse (15) in die . Konverterwand zusätzlich eingebaut ist.3. Device for performing the method according to claim 1 or 2,
characterized,
that above the bath level which forms in the filled AOD converter, at least one fuel gas-oxygen nozzle (15) corresponding to the AOD nozzles into the. Converter wall is also installed. 4. Vorrichtung nach Anspruch 3,
dadurch gekennzeichnet,
daß in den zur Bildung der Brenngas-Sauerstoff-Flammen dienenden Düsen eine Zündelektrode (24) zentrisch eingebaut ist.4. The device according to claim 3,
characterized,
that an ignition electrode (24) is installed centrally in the nozzles used to form the fuel gas-oxygen flames.
EP82105900A 1981-08-05 1982-07-02 Method of preheating and heating empty AOD converter vessels Withdrawn EP0071755A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3130972 1981-08-05
DE19813130972 DE3130972A1 (en) 1981-08-05 1981-08-05 "METHOD FOR PREHEATING AND HEATING EMPTY AOD CONVERTERS"

Publications (1)

Publication Number Publication Date
EP0071755A1 true EP0071755A1 (en) 1983-02-16

Family

ID=6138639

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82105900A Withdrawn EP0071755A1 (en) 1981-08-05 1982-07-02 Method of preheating and heating empty AOD converter vessels

Country Status (4)

Country Link
EP (1) EP0071755A1 (en)
JP (1) JPS5827919A (en)
DE (1) DE3130972A1 (en)
ES (1) ES514776A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT394395B (en) * 1989-01-13 1992-03-25 Veitscher Magnesitwerke Ag METALLURGICAL TUBE AND ARRANGEMENT THEREOF
FR2715882A1 (en) * 1994-02-09 1995-08-11 Lorraine Laminage Reheating or heating of inner walls of metallurgical vessels
CN103233097A (en) * 2013-05-03 2013-08-07 鄂州恺鑫铸业有限公司 Argon oxygen decarburization (AOD) furnace capable of shortening stainless steel refining time and method of furnace
WO2016162016A1 (en) * 2015-04-08 2016-10-13 Sms Group Gmbh Converter

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100380135B1 (en) * 1998-12-16 2003-08-21 주식회사 포스코 Refractory Thermal Burner
RU2710826C1 (en) * 2018-08-31 2020-01-14 Акционерное общество "ЕВРАЗ НТМК Нижнетагильский металлургический комбинат" (АО "ЕВРАЗ НТМК") Lining of converter bottom with bottom tuyeres

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DE1601276A1 (en) * 1967-04-17 1970-11-26 Air Reduction Double-sided oxygen-fuel burner
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DE2602178A1 (en) * 1975-07-30 1977-02-17 Uss Eng & Consult PROCESS FOR BURNING IN THE FIRE-RESISTANT LINING OF BOTTOM-BLUSHED STEEL FRESH DEVICES
DE2624592B2 (en) * 1975-06-25 1977-07-21 Creusot Loire Paris, Sprunck, Emile, Moyeuvre-Grande, Moselle, (Frankreich) DEVICE FOR HEATING METALLURGICAL CONVERTERS
DE2816543A1 (en) * 1978-04-17 1979-10-25 Maximilianshuette Eisenwerk Steel mfr. from solid ferrous material esp. scrap, in converter - where bottom tuyeres are used as fuel burners to preheat charge prior to melting and oxygen refining
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Patent Citations (9)

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Publication number Priority date Publication date Assignee Title
GB947032A (en) * 1961-10-18 1964-01-22 Voest Ag Blast burner
DE1508280B1 (en) * 1965-11-19 1969-09-04 Union Carbide Corp Nozzle for treating molten metal
DE1601276A1 (en) * 1967-04-17 1970-11-26 Air Reduction Double-sided oxygen-fuel burner
DE2065105A1 (en) * 1969-08-15 1972-11-30 Union Carbide Corp Metallurgical furnace elimination from 2037808
US3897048A (en) * 1973-06-15 1975-07-29 Pennsylvania Engineering Corp Metallurgical vessel and method of operating same
DE2624592B2 (en) * 1975-06-25 1977-07-21 Creusot Loire Paris, Sprunck, Emile, Moyeuvre-Grande, Moselle, (Frankreich) DEVICE FOR HEATING METALLURGICAL CONVERTERS
DE2602178A1 (en) * 1975-07-30 1977-02-17 Uss Eng & Consult PROCESS FOR BURNING IN THE FIRE-RESISTANT LINING OF BOTTOM-BLUSHED STEEL FRESH DEVICES
US4208206A (en) * 1977-03-31 1980-06-17 Union Carbide Corporation Method for producing improved metal castings by pneumatically refining the melt
DE2816543A1 (en) * 1978-04-17 1979-10-25 Maximilianshuette Eisenwerk Steel mfr. from solid ferrous material esp. scrap, in converter - where bottom tuyeres are used as fuel burners to preheat charge prior to melting and oxygen refining

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT394395B (en) * 1989-01-13 1992-03-25 Veitscher Magnesitwerke Ag METALLURGICAL TUBE AND ARRANGEMENT THEREOF
FR2715882A1 (en) * 1994-02-09 1995-08-11 Lorraine Laminage Reheating or heating of inner walls of metallurgical vessels
CN103233097A (en) * 2013-05-03 2013-08-07 鄂州恺鑫铸业有限公司 Argon oxygen decarburization (AOD) furnace capable of shortening stainless steel refining time and method of furnace
CN103233097B (en) * 2013-05-03 2014-12-17 鄂州恺鑫铸业有限公司 Argon oxygen decarburization (AOD) furnace capable of shortening stainless steel refining time and method of furnace
WO2016162016A1 (en) * 2015-04-08 2016-10-13 Sms Group Gmbh Converter
CN107636174A (en) * 2015-04-08 2018-01-26 Sms集团有限责任公司 Converter
CN107636174B (en) * 2015-04-08 2019-12-27 Sms集团有限责任公司 Converter
RU2711692C2 (en) * 2015-04-08 2020-01-21 Смс Груп Гмбх Converter

Also Published As

Publication number Publication date
DE3130972A1 (en) 1983-02-24
ES514776A1 (en) 1983-05-01
JPS5827919A (en) 1983-02-18

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