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EP0730667B1 - Process and device for introducing gases into metal melts - Google Patents

Process and device for introducing gases into metal melts Download PDF

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Publication number
EP0730667B1
EP0730667B1 EP94928757A EP94928757A EP0730667B1 EP 0730667 B1 EP0730667 B1 EP 0730667B1 EP 94928757 A EP94928757 A EP 94928757A EP 94928757 A EP94928757 A EP 94928757A EP 0730667 B1 EP0730667 B1 EP 0730667B1
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EP
European Patent Office
Prior art keywords
gas
ducts
space
vessel
melt
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EP94928757A
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German (de)
French (fr)
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EP0730667A1 (en
Inventor
Anatoly Sizov
Horst-Dieter Schöler
Ulrich Meyer
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Vodafone GmbH
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Mannesmann AG
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/05—Refining by treating with gases, e.g. gas flushing also refining by means of a material generating gas in situ
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
    • B22D1/002—Treatment with gases
    • B22D1/005—Injection assemblies therefor
    • 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
    • C21C5/4673—Measuring and sampling 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/48—Bottoms or tuyéres of converters

Definitions

  • the invention relates to a method for introducing gases into a molten metal located in metallurgical vessels channels and one arranged in the refractory lining of the vessel Device for this.
  • the gas is usually passed through gas purging plugs, where one differentiates between permeable and dense sinks.
  • the gas flows directly through the permeable purge stones Stone structure, which has a capillary system in the The order of 10 to 20 Nperm. With this capillary size, sufficient gas can melt are supplied while the liquid melt itself is not in the Capillaries penetrates.
  • the dense sink blocks are either with directed flushing channels or with flushing tubes or slots.
  • a gas-permeable structure is known from the document EP 0 146 079 A2 fireproof material for blowing gases into metal treatment vessels known through their clothing, in which a Gas distribution room against the refractory material through a sheet metal plate is completed, in which channels are tightly attached. These channels are designed as nozzle tubes, which narrow gaps by compressing form with an inner width of about 0.3 to 1 mm.
  • the 6as is a capillary system of the permeable gas purging plug or through purging channels or slots of the dense gas purging plug.
  • the amount of gas to be enforced is limited.
  • the gas continuously as a spontaneous and therefore uncontrollable flow given up.
  • the conditions of the rinsing process are chosen so that they have little influence on the hydromatics of the molten metal.
  • the type of gas discharge corresponds to that in most cases Blowing process.
  • the outflowing 6as jet unfolds its kinetic Effect on the melt only in the vicinity of the gas purging plug.
  • the capillary or channel system of the gas purging stones has a large one Flow resistance on.
  • gas flows out of the known Gas purging stones can, especially with high gas throughput, as a result of Mixing small bubbles to form large-volume bubbles.
  • the invention has set itself the goal of avoiding the aforementioned disadvantages and of specifying a method and creating a corresponding device in which, with low energy losses, a deeper penetration of the gas jet into the better mixing with the liquid melt is made possible, as well as homogenization - and cleaning time of the melt is shortened.
  • the invention achieves this goal by the characterizing features of method claim 1 and device claim 5.
  • the gas is fed into a gas distributor before entering the molten metal, in which sound generators are provided to excite the gas vibrations.
  • sound generators are provided to excite the gas vibrations.
  • the behavior of the gas vibrations and their frequency can be changed in areas.
  • shock waves are generated which propagate through the gas distributor and enter the channels.
  • the vibrations of the gas jet, the interaction of the currents and the formation of the shock waves within the sound generator are controlled in a predeterminable frequency and amplitude depending on the characteristics of the purging process and on the environment into which the gas flows.
  • the excited gas is supplied to the melt through channels combined in a bundle.
  • the thin jets flowing out of the channel bundle attract each other behind the nozzle mouth and thus stabilize the outgoing gas jet.
  • This stable gas system causes a vortex system of high intensity in the molten metal and has a positive influence on the mixing process of the molten metal in the metallurgical vessel to a high degree.
  • the vortex system influences the molten metal not only kinetically but also in terms of vibrations.
  • the interaction between the gas flow and the molten metal has a radiation character.
  • a vortex system with longitudinal and transverse waves is created in the metallurgical vessel.
  • the channels of the gas purging block have a triangular cross-sectional area through which the gas jet is free of resonance by destroying the longitudinal vortex system, since the gas jet oscillation does not resonate due to reflection on the channel wall, and thus melts without hindrance.
  • the rays with ultrasonic vibrations emanating from the mouth of the triangular channels have a high absorbency.
  • the melt is sucked in between the beams, crushed or broken in the system of coherent transverse vortices in an ultrasonic field.
  • a two-phase flow is formed, among other things, by reducing the partial pressure of the dissolved gases from the melt.
  • the jet core spreads in this two-phase flow, which enables a long range of the jet.
  • a form of the device which prevents the molten metal from flowing out of the metallurgical vessel via the gas distributor.
  • metallic components are provided which, when the pressure of the purge gas decreases, cool the penetrating metal melt to such an extent that it freezes.
  • FIG. 1 shows a metallurgical vessel 10 with the metallic jacket 11 and the refractory lining 12.
  • a refractory structure 40 is provided as a gas purging stone.
  • a 6as distributor 20 is arranged below the base 13 and is connected via a gas supply line 31 to a gas supply station 30 (not shown).
  • the melt S is located in the vessel 10.
  • the arrows show the direction of flow of the melt about the central axis I.
  • FIG. 2 shows the refractory body 40 as well as the Gas distributor 20, which via the feed line 31 to the Gas supply station 30 is connected.
  • the gas distributor 20 has an anteroom 21 and a main room 22.
  • an annular groove 23 provided that is guided coaxially to the main axis I. Perpendicular to the An annular groove 23 is provided in a disk groove 24. Both grooves are as Sound generators trained and vibrate the gas in the Ultrasound range.
  • a support ring 25 on the inner wall of the gas distributor 20.
  • This support ring is designed such that both the sound generator designed as an annular groove and the sound generator designed as a disk groove can have a comprehensive influence on the gas.
  • a plate 52 is provided in the main room 22, which is supported via support elements 53.
  • This plate 52 has a circular shape and is made of metal, which freezes when the melt possibly enters against the direction of flow of the gas and prevents it from escaping from the vessel or the gas distributor.
  • the housing of the gas distributor 20 is attached to the jacket 11 of the metallurgical vessel 10.
  • the structure 40 is arranged in a housing 14 in a configuration as shown in the left side of the sketch.
  • Channels 41, 42, 43 are introduced into the carrier body 44 made of ceramic material.
  • part of the channel 41 is in the form of a metal tube 51 and the tube length L1 is approximately half the length L2 of the carrier body 44.
  • a seal 47 is introduced between the outlet 27 of the main chamber 22 and the carrier body 44.
  • FIG. 3 shows a top view of the channels 41 to 43. These channels have a cross-sectional area in the form of an isosceles triangle.
  • the individual channels 41, 42, 43 are arranged parallel to each other.
  • the letter a means the channel width
  • the letter b the distance between two channel axes if the channels are arranged parallel to each other
  • the letter l the length of a triangular channel.
  • the individual channels are inclined to each other, namely at an angle ⁇ or ⁇ .

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Furnace Charging Or Discharging (AREA)
  • Coating With Molten Metal (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Chemical Vapour Deposition (AREA)

Abstract

PCT No. PCT/DE94/01180 Sec. 371 Date Jul. 1, 1996 Sec. 102(e) Date Jul. 1, 1996 PCT Filed Sep. 28, 1994 PCT Pub. No. WO95/10634 PCT Pub. Date Apr. 20, 1995A process and a device for introducing gases into a metal melt contained in metallurgical vessels via ducts arranged in the refractory lining of the vessel. In order to permit deeper penetration of the jet of gas and better mixing with the melt, an oscillating jet of gas is produced and introduced into the melt. For this purpose, several acoustic generators with which the gas is brought into contact with the melt are provided in the device.

Description

Die Erfindung betrifft ein Verfahren zum Einleiten von Gasen in eine in metallurgischen Gefäßen sich befindende Metallschmelze über in der Feuerfestauskleidung des Gefäßes angeordnete Kanäle und eine Vorrichtung dazu.The invention relates to a method for introducing gases into a molten metal located in metallurgical vessels channels and one arranged in the refractory lining of the vessel Device for this.

Ein Verfahren sowie eine Vorrichtung mit den Merkmalen in den Oberbegriffen der Ansprüche 1 und 5 ist aus dem "Patent Abstracts of Japan" (Vol. 15, No. 76, C-809, 21. Febr. 1991) mit der JP-A-02 301 525 bekannt.A method and a device with the features in the The preamble of claims 1 and 5 is from "Patent Abstracts of Japan "(Vol. 15, No. 76, C-809, Feb. 21, 1991) with JP-A-02 301 525 known.

Allgemein sind verschiedene Gasspülsysteme in Stahlwerken zum Einleiten von Gasen in metallurgische Schmelzen bekannt, die im wesentlichen zum Homogenisieren und Reinigen der Schmelzen dienen. Im allgemeinen wird das Gas Argon oder Stickstoff eingesetzt. Ein weiteres Einsatzfeld ist das Bodenblasverfahren mit Sauerstoff in Metallbehandlungsgefäßen, wie Ofenpfannen, Entschwefelungspfannen u.ä. Hierbei erfolgt das Einblasen von Gasen in das Metallbad durch den Gefäßboden und die Auskleidung der Gefäßwände.In general, various gas purging systems are used in steelworks Introducing gases into metallurgical melts known in the essential for homogenizing and cleaning the melts. In general, the gas argon or nitrogen is used. A Another application is the bottom blowing process with oxygen in Metal treatment vessels, such as furnace pans, desulfurization pans etc. Here, gases are blown into the metal bath the vessel bottom and the lining of the vessel walls.

Das Gas wird üblicherweise durch Gasspülsteine geführt, bei denen man zwischen permeablen und dichten Spülsteinen unterscheidet. Bei den permeablen Spülsteinen strömt das Gas direkt durch das Steingefüge, welches ein Kapillarsystem aufweist in der Größenordnung von 10 bis 20 Nperm. Bei dieser Kapillargröße kann ausreichend Gas der Schmelze zugeführt werden, während die Flüssigschmelze selbst nicht in die Kapillaren eindringt. Die dichtenSpülsteine sind entweder mit gerichteten Spülkanälen oder mit Spülröhrchen bzw. Schlitzen versehen.The gas is usually passed through gas purging plugs, where one differentiates between permeable and dense sinks. At The gas flows directly through the permeable purge stones Stone structure, which has a capillary system in the The order of 10 to 20 Nperm. With this capillary size, sufficient gas can melt are supplied while the liquid melt itself is not in the Capillaries penetrates. The dense sink blocks are either with directed flushing channels or with flushing tubes or slots.

So ist aus der Schrift DE 41 01 833 C2 eine Vorrichtung zum Einleiten von Gas in beliebige metallurgische Gefäße, insbesondere von Liftgas in den Rüssel eine Vakuumanlage bekannt, bei der die Liftgasdüsen aus einem oder mehreren Schlitzen bestehen, die eine Breite von 0,2 bis 0,8 mm haben. Die Liftgasdüsen sind dabei rückseitig direkt an eine Gasleitung angeschlossen.From DE 41 01 833 C2 there is a device for introducing of gas in any metallurgical vessels, in particular lift gas in the proboscis known a vacuum system, in which the lift gas nozzles one or more slits, which have a width of 0.2 to 0.8 mm have. The lift gas nozzles are directly on the back of one Gas line connected.

Aus der Schrift EP 0 146 079 A2 ist eine gasdurchlässiger Baukörper aus feuerfestem Material zum Einblasen von Gasen in Metallbehandlungsgefäße durch deren Ruskleidung hindurch bekannt, bei dem ein Gasverteilungsraum gegen das feuerfeste Material durch eine Blechplatte abgeschlossen ist, in der Kanäle dicht befestigt sind. Diese Kanäle sind als Düsenrohre ausgebildet, die durch Zusammendrücken enge Spalten bilden mit einer Innenbreite von etwa 0,3 bis 1 mm.A gas-permeable structure is known from the document EP 0 146 079 A2 fireproof material for blowing gases into metal treatment vessels known through their clothing, in which a Gas distribution room against the refractory material through a sheet metal plate is completed, in which channels are tightly attached. These channels are designed as nozzle tubes, which narrow gaps by compressing form with an inner width of about 0.3 to 1 mm.

Bei den bekannten Vorrichtungen wird das 6as durch ein Kapillarsystem des permeablen Gasspülsteines oder durch Spülkanäle bzw. -schlitze des dichten Gasspülsteins geführt. In den bekannten Gaseinleitvorrichtungen ist die durchzusetzende Gasmenge begrenzt. Außerdem wird das Gas kontinuierlich als eine spontane und damit nicht steuerbare Strömung aufgegeben. Die Bedingungen des Spülvorgangs sind dabei so gewählt, daß sie auf die Hydromatik der Metallschmelze nur gering Einwirkung nehmen. Die Gasauströmungsart entspricht in den meisten Fällen dem Blasverfahren. Der ausströmende 6asstrahl entfaltet seine kinetische Wirkung auf die Schmelze nur in der Nähe des Gasspülsteins. In the known devices, the 6as is a capillary system of the permeable gas purging plug or through purging channels or slots of the dense gas purging plug. In the known gas injection devices the amount of gas to be enforced is limited. In addition, the gas continuously as a spontaneous and therefore uncontrollable flow given up. The conditions of the rinsing process are chosen so that they have little influence on the hydromatics of the molten metal. The type of gas discharge corresponds to that in most cases Blowing process. The outflowing 6as jet unfolds its kinetic Effect on the melt only in the vicinity of the gas purging plug.

Das Kapillar- bzw. das Kanalsystem der Gasspülsteine weist einen großen Strömungswiderstand auf. Beim Gasauströmen aus den bekannten Gasspülsteinen können, insbesondere bei hohem Gasdurchsatz, infolge des Vermischens kleiner Bläschen großvolumige Blasen gebildet werden.The capillary or channel system of the gas purging stones has a large one Flow resistance on. When gas flows out of the known Gas purging stones can, especially with high gas throughput, as a result of Mixing small bubbles to form large-volume bubbles.

Außerdem weisen die vorhandenen Ausführungen von permeablen Gasspülsteinen eine geringe Intensität beim Vermischen der Metallschmelze und einen geringen Nutzfaktor der Strömungsenergie auf.In addition, the existing versions of permeable Gas purging stones have a low intensity when mixing the Molten metal and a low useful factor of flow energy.

Beim Einsatz von Schlitzkanälen treten während des Durchströmens der Gase durch die Kanäle Längswirbelgeflechte auf mit der Folge, daß der Gasstrahl behindert wird und keine ausreichende Intensität beim Vermischen der Metallschmelze aufweist. Dies hat selbst beim Einsatz mehrerer Kanäle nebeneinander zur Folge, daß sich die Strahlen in einer Reihe von dünnen instabilen Strahlen trennen, was wiederum die Durchmischung der Schmelze mindert.
Die Erfindung hat sich das Ziel.gesetzt, die vorgenannten Nachteile zu meiden und ein Verfahren anzugeben und eine dazu entsprechende Vorrichtung zu schaffen, bei der mit geringen Energieverlusten ein tieferes Eindringen des Gasstrahls in die und bessere Vermischung mit der Flüssigschmelze ermöglicht wird, sowie die Homogenisierung- und Reinigungszeit der Schmelze verkürzt wird.
Die Erfindung erreicht dieses Ziel durch die kennzeichnenden Merkmale des Verfahrensanspruchs 1 und des Vorrichtungsanspruchs 5.When slot channels are used, longitudinal vortex meshes occur as the gases flow through the channels, with the result that the gas jet is obstructed and does not have sufficient intensity when the molten metal is mixed. Even when several channels are used side by side, this has the consequence that the jets separate into a series of thin, unstable jets, which in turn reduces the mixing of the melt.
The invention has set itself the goal of avoiding the aforementioned disadvantages and of specifying a method and creating a corresponding device in which, with low energy losses, a deeper penetration of the gas jet into the better mixing with the liquid melt is made possible, as well as homogenization - and cleaning time of the melt is shortened.
The invention achieves this goal by the characterizing features of method claim 1 and device claim 5.

Beim vorgeschlagenen Verfahren wird das Gas vor Eintritt in die Metallschmelze in einen Gasverteiler geführt, in dem Schallgeneratoren zur Anregung der Gasschwinqungen vorgesehen sind. Je nach den Kenndaten des Spülgases in der Gasleitung und der Rusführung der Schallgeneratoren können das Verhalten der Gasschwingungen und deren Frequenz in Bereichen geändert werden. Beim Anregen des Gases durch die Schallgeneratoren entstehen Stoßwellen, die sich durch den Gasverteiler fortpflanzen und in die Kanäle gelangen.
Die Schwingungen des Gasstrahls, die Wechselwirkung der Strömungen und die Bildung der Stoßwellen innerhalb des Schallgenerators werden in Abhängigkeit der Kenndaten des Spülvorgangs sowie von der Umgebung, in die das Gas mündet, in einer vorgebbaren Frequenz und Amplitude gesteuert.
Das angeregte Gas wird durch in einem Bündel vereinigte Kanäle der Schmelze zugeführt. Die aus dem Kanalbündel ausströmenden dünnen Strahlen ziehen sich hinter der Düsenmündung einander an und stabilisieren somit den ausströmenden Gesamtgasstrahl. Dieses stabile Gassystem ruft in der Metallschmelze ein Wirbel system von hoher Intensität hervor und beeinfluß positiv den Vermischungsvorgang der Metallschmelze in dem metallurgischen Gefäß in hohem Maße. Das Wirbelsystem beeinflußt dabei die Metallschmelze nicht nur kinetisch, sondern auch schwingungsmäßig. Die Wechselwirkung zwischen der Gasströmung und der Metallschmelze weist einen Strahlencharakter auf. Es entsteht im metallurgischen Gefäß ein Wirbelsystem mit Längs- und Querwellen.
Die Kanäle des Gasspülsteins besitzen eine dreiecke Querschnittsfläche, durch die der Gasstrahl durch Zerstörung des Längswirbelsystems resonanzfrei, da eine Resonanz der Gasstrahlschwingung durch Reflektion an der Kanalwandung nicht auftritt, und somit ohne Behinderungen zur Schmelze gelangt.
Die von der Mündung der Dreieckskanäle ausströmenden Strahlen mit Ultraschallschwingungen weisen eine hohe Saugfähigkeit auf. Die Schmelze wird zwischen die Strahlen eingesaugt, im System der kohärenten Querwirbel im Ultraschallfeld zerkleinert bzw. gebrochen. Es bildet sich u.a. durch Minderung des Partialdruckes der aufgelösten Gase aus der Schmelze eine Zweiphasenströmung. Der Strahlkern verbreitet sich in dieser Zweiphasenströmung, was eine hohe Reichweite des Strahls ermöglicht. Ein negativer Einfluß von sonst üblichen kleinen und großen Blasen und die hierbei auftretende Blasenschwingung wird beseitigt. In einer vorteilhaften Ausgestaltung ist unter Beibehaltung aller Vorteile des aufgezeigten Verfahrens eine Form der Vorrichtung aufgezeigt, die ein Ausströmen der Metallschmelze aus dem metallurgischen Gefäß über den Gasverteiler verhindert. Hierzu sind metallische Bauteile vorgesehen, die bei einem Nachlassen des Druckes des Spülgases die eindringende Metallschmelze so stark abkühlen, daß sie einfriert.In the proposed method, the gas is fed into a gas distributor before entering the molten metal, in which sound generators are provided to excite the gas vibrations. Depending on the characteristics of the purge gas in the gas line and the configuration of the sound generators, the behavior of the gas vibrations and their frequency can be changed in areas. When the gas is excited by the sound generators, shock waves are generated which propagate through the gas distributor and enter the channels.
The vibrations of the gas jet, the interaction of the currents and the formation of the shock waves within the sound generator are controlled in a predeterminable frequency and amplitude depending on the characteristics of the purging process and on the environment into which the gas flows.
The excited gas is supplied to the melt through channels combined in a bundle. The thin jets flowing out of the channel bundle attract each other behind the nozzle mouth and thus stabilize the outgoing gas jet. This stable gas system causes a vortex system of high intensity in the molten metal and has a positive influence on the mixing process of the molten metal in the metallurgical vessel to a high degree. The vortex system influences the molten metal not only kinetically but also in terms of vibrations. The interaction between the gas flow and the molten metal has a radiation character. A vortex system with longitudinal and transverse waves is created in the metallurgical vessel.
The channels of the gas purging block have a triangular cross-sectional area through which the gas jet is free of resonance by destroying the longitudinal vortex system, since the gas jet oscillation does not resonate due to reflection on the channel wall, and thus melts without hindrance.
The rays with ultrasonic vibrations emanating from the mouth of the triangular channels have a high absorbency. The melt is sucked in between the beams, crushed or broken in the system of coherent transverse vortices in an ultrasonic field. A two-phase flow is formed, among other things, by reducing the partial pressure of the dissolved gases from the melt. The jet core spreads in this two-phase flow, which enables a long range of the jet. A negative influence of the usual small and large bubbles and the bubble oscillation that occurs are eliminated. In an advantageous embodiment, while maintaining all the advantages of the method shown, a form of the device is shown which prevents the molten metal from flowing out of the metallurgical vessel via the gas distributor. For this purpose, metallic components are provided which, when the pressure of the purge gas decreases, cool the penetrating metal melt to such an extent that it freezes.

Ein Beispiel der Erfindung ist in der beigefügten Zeichnung dargestellt. Dabei zeigen die:

  • Figur 1 einen Schnitt durch ein metallurgisches Gefäß
  • Figur 2 einen Schnitt durch einen Gasverteiler und einen Gasspülstein.
  • Figur 3 Draufsicht auf die Kanäle
    • An example of the invention is shown in the accompanying drawing. The show:
  • 1 shows a section through a metallurgical vessel
  • Figure 2 shows a section through a gas distributor and a gas purging plug.
  • Figure 3 top view of the channels

    • Die Figur 1 zeigt ein metallurgisches Gefäß 10 mit dem metallischen Mantel 11 und der Feuerfestauskleidung 12. Im Boden 13 des Gefäßes 10 ist als Gasspülstein ein feuerfester Baukörper 40 vorgesehen. Unterhalb des Bodens 13 ist ein 6asverteiler 20 angeordnet, der über eine Gaszuführleitung 31 an eine nicht weiter dargestellte Gasversorgungsstation 30 angeschlossen ist.
    Im Gefäß 10 befindet sich die Schmelze S. Mit den Pfeilen ist die Strömungsrichtung der Schmelze um die Zentralachse I aufgezeigt.    FIG. 1 shows a metallurgical vessel 10 with the metallic jacket 11 and the refractory lining 12. In the bottom 13 of the vessel 10, a refractory structure 40 is provided as a gas purging stone. A 6as distributor 20 is arranged below the base 13 and is connected via a gas supply line 31 to a gas supply station 30 (not shown).
    The melt S is located in the vessel 10. The arrows show the direction of flow of the melt about the central axis I.

    Die Figur 2 zeigt im Detail den Feuerfestkörper 40 sowie den Gasverteiler 20, der über die Zuführleitung 31 an die Gasversorgungsstation 30 angeschlossen ist. FIG. 2 shows the refractory body 40 as well as the Gas distributor 20, which via the feed line 31 to the Gas supply station 30 is connected.

    Der Gasverteiler 20 weist einen Vorraum 21 und einen Hauptraum 22 auf. Im Bereich der Mündung 26 des Vorraums 21 ist eine Ringnut 23 vorgesehen, die koaxial zur Hauptachse I geführt ist. Senkrecht zur Ringnut 23 ist eine Scheibennut 24 vorgesehen. Beide Nuten sind als Schallgeneratoren ausgebildet und versetzen das Gas in Schwingungen im Ultraschallbereich.The gas distributor 20 has an anteroom 21 and a main room 22. In the area of the mouth 26 of the vestibule 21 there is an annular groove 23 provided that is guided coaxially to the main axis I. Perpendicular to the An annular groove 23 is provided in a disk groove 24. Both grooves are as Sound generators trained and vibrate the gas in the Ultrasound range.

    Zwischen dem Vor raum 21 und dem Hauptraum 22 befindet sich an der Innenwand des Gasverteilers 20 ein Tragring 25.Dieser Tragring ist so ausgebildet, daß sowohl der als Ringnut ausgeführte Schallgenerator wie auch der als Scheibennut ausgeführte Schallgenerator umfassend Einfluß auf das Gas nehmen können.
    Im linken Teil der Skizze ist im Hauptraum 22 eine Platte 52 vorgesehen, die sich über Stützelemente 53 abstützt. Diese Platte 52 weist eine kreisförmige Form auf und ist aus Metall, welches beim möglicherweise entgegen der Strömungsrichtung des Gases eintretende Schmelze einfriert und einen Austritt aus dem Gefäß bzw. dem Gasverteiler verhindert. Das Gehäuse des Gasverteilers 20 ist an dem Mantel 11 des metallurgischen Gefäßes 10 befestigt.
    In der Feuerfestauskleidung 12 ist der Baukörper 40, in einer Rusführungsform wie in der linken Seite der Skizze dargestellt, in einem Gehäuse 14, angeordnet. In dem aus keramischem Material bestehenden Trägerkörper 44 sind Kanäle 41, 42, 43 eingebracht.
    Auf der linken Seite der Skizze ist ein Teil des Kanals 41 in Form eines Metallrohres 51 ausgebildet und die Rohrlänge L1 ist etwa halb so groß wie die Länge L2 des Trägerkörpers 44.
    Zwischen dem Ausgang 27 der Hauptkammer 22 und dem Trägerkörper 44 ist eine Dichtung 47 eingebracht.    Between the front space 21 and the main space 22 there is a support ring 25 on the inner wall of the gas distributor 20. This support ring is designed such that both the sound generator designed as an annular groove and the sound generator designed as a disk groove can have a comprehensive influence on the gas.
    In the left part of the sketch, a plate 52 is provided in the main room 22, which is supported via support elements 53. This plate 52 has a circular shape and is made of metal, which freezes when the melt possibly enters against the direction of flow of the gas and prevents it from escaping from the vessel or the gas distributor. The housing of the gas distributor 20 is attached to the jacket 11 of the metallurgical vessel 10.
    In the refractory lining 12, the structure 40 is arranged in a housing 14 in a configuration as shown in the left side of the sketch. Channels 41, 42, 43 are introduced into the carrier body 44 made of ceramic material.
    On the left side of the sketch, part of the channel 41 is in the form of a metal tube 51 and the tube length L1 is approximately half the length L2 of the carrier body 44.
    A seal 47 is introduced between the outlet 27 of the main chamber 22 and the carrier body 44.

    Die Figur 3 zeigt eine Draufsicht der Kanäle 41 bis 43. Diese Kanäle besitzen eine Querschnittsfläche in Form eines gleichschenkligen Dreiecks.
    Im oberen Teil der Figur 3 sind die einzelnen Kanäle 41, 42, 43 parallel zueinander angeordnet. Dabei bedeutet der Buchstabe a die Kanalbreite, der Buchstabe b der Abstand zweier Kanalachsen, wenn die Kanäle parallel zueinander angeordnet sind und der Buchstabe l die Länge eines dreiecken Kanals.
    Im unteren Teil der Figur 3 sind die einzelnen Kanäle zueinander geneigt, und zwar in einem Neigungwinkel α bzw. β.     FIG. 3 shows a top view of the channels 41 to 43. These channels have a cross-sectional area in the form of an isosceles triangle.
    In the upper part of Figure 3, the individual channels 41, 42, 43 are arranged parallel to each other. The letter a means the channel width, the letter b the distance between two channel axes if the channels are arranged parallel to each other and the letter l the length of a triangular channel.
    In the lower part of Figure 3, the individual channels are inclined to each other, namely at an angle α or β.

    PositionslistePosition list

    1010th
    metallurgisches Gefäßmetallurgical vessel
    1111
    Mantelcoat
    1212th
    FeuerfestauskleidungRefractory lining
    1313
    Bodenground
    1414
    Gehäuse für SpülsteinHousing for sink
    2020th
    GasverteilerGas distributor
    2121
    VorraumAnteroom
    2222
    HauptraumMain room
    2323
    RingnutRing groove
    2424th
    ScheibennutDisc groove
    2525th
    TragringSupport ring
    2626
    Mündung VorraumEstuary entrance hall
    2727
    Ausgang HauptraumExit main room
    3030th
    GasversorgungsstationGas supply station
    3131
    GaszufuhrleitungGas supply line
    4040
    feuerfester Baukörperfireproof structure
    41, 42, 4341, 42, 43
    Kanalchannel
    4444
    TrägerkörperCarrier body
    4545
    MetallrohrMetal pipe
    4646
    metallische Plattemetallic plate
    4747
    Dichtungpoetry
    5050
    KühlelementCooling element
    5151
    Rohrpipe
    5252
    Platteplate
    5353
    StützelementSupport element
    SS
    Schmelzemelt
    II.
    ZentralachseCentral axis
    α,βα, β
    NeigungswinkelAngle of inclination

    Claims (11)

    1. A method for introducing gases into a molten metal located in metallurgical vessels via ducts arranged in the refractory lining of the vessel, the gas, after entry into a preliminary gas distribution space, flowing around a first sound generator and being fed via ducts to the melt located in the vessel,
      characterised by the following steps:
      a) the oscillating gas jet is fed to at least a second sound generator and is excited to periodic pulsating oscillation, and
      b) then the gas jet excited repeatedly to oscillation is passed into a main gas distribution space.
    2. A method according to Claim 1, characterised in that the gas jet excited to oscillation is fed to the melt via a group of at least three ducts in the form of a bundle of jets.
    3. A method according to Claim 2, characterised in that the gas jet flows through the ducts free of resonance.
    4. A method according to Claim 1, characterised in that the pulse frequency of the gas at a pressure of 2 to 10 bar is set to 20 to 500 Hz.
    5. An apparatus for introducing gases into a molten metal located in a metallurgical vessel, having a gas feed line connected to a gas supply station, which line opens into a gas distributor to which an element arranged in the refractory material of the vessel and having slot-shaped ducts is connected, and having a sound generator, for performing the method according to Claim 1,
      characterised in that
      the gas distributor (20) has a preliminary space (21) on the gas entry side,
      that an annular groove (23) arranged coaxially to the central axis (I) and designed as the first sound generator is located in the region of the mouth (26) of the preliminary space (21),
      that a disc groove (24) designed as a second sound generator is provided adjoining the mouth of the annular groove (23) and extending radially outwards,
      that a supporting ring (25) projects into the interior of the gas distributor in the direction of the gas flow after the disc groove (24) and separates the preliminary space (21) from a main space (22), and that at least three slot-shaped ducts (41, 42, 43) arranged paraxially to one another and opening on to the inside of the vessel base (13) are provided at the outlet (27) of the main space (22).
    6. An apparatus according to Claim 5, characterised in that the slot-shaped ducts (41, 42, 43) have a cross-sectional surface formed as an isosceles triangle.
    7. An apparatus according to Claim 6, characterised in that the ratio of the distance between the duct axes b to the duct width a for a parallel arrangement of the ducts is b/a = 1.06 to 2.08 for a length of the duct nozzle e which is in a ratio to the width a of l/a = 13.1 to 14.6.
    8. An apparatus according to Claim 7, characterised in that the triangular ducts are inclined at an angle, relative to each other, the angles of inclination α and β being adjustable within the range from 0 to 90 degrees.
    9. An apparatus according to Claim 5, characterised in that the part of the slot-shaped ducts (41, 42, 43) facing the main space (22) is constructed from a metal pipe (51).
    10. An apparatus according to Claim 9, characterised in that a metal plate (52) is provided in the main space (22) in a plane at right-angles to the central axis (I).
    11. An apparatus according to Claim 10, characterised in that the metal plate (52) is circular and is supported by means of elements (53) on the wall of the preliminary space (21).
    EP94928757A 1993-10-15 1994-09-28 Process and device for introducing gases into metal melts Expired - Lifetime EP0730667B1 (en)

    Applications Claiming Priority (3)

    Application Number Priority Date Filing Date Title
    DE4335643 1993-10-15
    DE4335643A DE4335643C1 (en) 1993-10-15 1993-10-15 Method and apparatus for introducing gases into metal melts
    PCT/DE1994/001180 WO1995010634A1 (en) 1993-10-15 1994-09-28 Process and device for introducing gases into metal melts

    Publications (2)

    Publication Number Publication Date
    EP0730667A1 EP0730667A1 (en) 1996-09-11
    EP0730667B1 true EP0730667B1 (en) 1998-10-28

    Family

    ID=6500506

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP94928757A Expired - Lifetime EP0730667B1 (en) 1993-10-15 1994-09-28 Process and device for introducing gases into metal melts

    Country Status (7)

    Country Link
    US (1) US5803948A (en)
    EP (1) EP0730667B1 (en)
    CN (1) CN1038046C (en)
    AT (1) ATE172752T1 (en)
    AU (1) AU7806594A (en)
    DE (2) DE4335643C1 (en)
    WO (1) WO1995010634A1 (en)

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    US6308436B1 (en) 1998-07-01 2001-10-30 The Procter & Gamble Company Process for removing water from fibrous web using oscillatory flow-reversing air or gas
    DE69910578T2 (en) 1998-07-01 2004-06-24 Institute Of Paper Science And Technology, Inc. METHOD FOR REMOVING WATER FROM FIBROUS CARBINS WITH OSCILLATING PRELIMINARY FLOW REVERSE
    DE19835272A1 (en) * 1998-08-04 2000-02-10 Linde Ag Process for introducing oxygen and / or an oxygen-containing gas mixture into a melt
    DE10035593A1 (en) * 2000-07-21 2002-01-31 Norddeutsche Affinerie Reducing oxygen content of copper melt comprises melting copper initially in shaft furnace, and subsequently feeding it to treatment furnace via transporting channel
    US6805831B2 (en) * 2002-05-10 2004-10-19 Luis Paredes Rojas Mechanical waves generator system in a converter or pyrometallurgical furnace
    US6790406B2 (en) * 2002-05-10 2004-09-14 Luis Paredes Rojas Mechanical waves generator system in a converter or pyrometallurgical furnace
    US6787099B2 (en) * 2002-05-10 2004-09-07 Luis Paredes Rojas Mechanical waves generator system in a converter or pyrometallurgical furnace
    US6786082B2 (en) * 2002-05-13 2004-09-07 Luis Paredes Rojas System for a non-invasive online continuous measurement of phase levels in converters or pyrometallurgical furnaces
    US6792358B2 (en) * 2002-05-13 2004-09-14 Luis Paredes Rojas System for a non-invasive online continuous measurement of phrase levels in converters or pyrometallurgical furnaces
    US6836734B2 (en) * 2002-05-13 2004-12-28 Luis Paredes Rojas System for a non-invasive online discrete measurement of phase levels in converters or pyrometallurgical furnaces
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    US8652397B2 (en) * 2010-04-09 2014-02-18 Southwire Company Ultrasonic device with integrated gas delivery system
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    CN102559993A (en) * 2012-01-18 2012-07-11 中冶赛迪工程技术股份有限公司 Device and method for stirring metallic molten pool by using pulsating gas
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    Also Published As

    Publication number Publication date
    DE4335643C1 (en) 1994-10-27
    AU7806594A (en) 1995-05-04
    US5803948A (en) 1998-09-08
    EP0730667A1 (en) 1996-09-11
    CN1038046C (en) 1998-04-15
    CN1135240A (en) 1996-11-06
    ATE172752T1 (en) 1998-11-15
    DE59407192D1 (en) 1998-12-03
    WO1995010634A1 (en) 1995-04-20

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