EP0037809B1 - Method of and arrangement for producing molten pig iron or steel prematerial - Google Patents

Method of and arrangement for producing molten pig iron or steel prematerial Download PDF

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Publication number
EP0037809B1
EP0037809B1 EP81890058A EP81890058A EP0037809B1 EP 0037809 B1 EP0037809 B1 EP 0037809B1 EP 81890058 A EP81890058 A EP 81890058A EP 81890058 A EP81890058 A EP 81890058A EP 0037809 B1 EP0037809 B1 EP 0037809B1
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European Patent Office
Prior art keywords
fluidized bed
plasma
oxygen
iron
gas
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German (de)
French (fr)
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EP0037809A1 (en
Inventor
Kurt Dipl.-Ing. Stift
Walter Dipl.-Ing. Dr. Lugscheider
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Voestalpine AG
Deutsche Voest Alpine Industrieanlagenbau GmbH
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Voestalpine AG
Deutsche Voest Alpine Industrieanlagenbau GmbH
Korf Engineering GmbH
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/12—Making spongy iron or liquid steel, by direct processes in electric furnaces
    • C21B13/125—By using plasma
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/0006—Making spongy iron or liquid steel, by direct processes obtaining iron or steel in a molten state
    • C21B13/0013—Making spongy iron or liquid steel, by direct processes obtaining iron or steel in a molten state introduction of iron oxide into a bath of molten iron containing a carbon reductant
    • C21B13/002—Reduction of iron ores by passing through a heated column of carbon

Definitions

  • the invention relates to a process for the production of molten pig iron or steel raw material from iron oxide-containing raw material particles, in particular pre-reduced iron ore, in which iron oxide-containing raw material particles are introduced from above into a fluidized bed formed from coal particles and an oxygen-containing carrier gas and heated, reduced and melted during passage through the same, and one Plant for carrying out the process.
  • the oxygen-containing carrier gas must be introduced just above the slag bath surface so that the fluidized bed reaches this surface. For this reason, in the known processes in the lower region of the fluidized bed, that is to say just above the slag bath surface, a zone with the highest temperature of the fluidized bed (high-temperature zone) is formed. This has the disadvantage that reoxidation of the iron ore particles which have already been reduced cannot be avoided with certainty in this zone.
  • the invention aims to avoid these disadvantages and difficulties and has the object to provide a method of the type described above and a system for carrying out the method in which the total energy use can be significantly reduced with much cheaper energy use, so that the reduction and Melting process can be carried out more economically than before.
  • the fluidized bed is additionally supplied with energy by plasma heating, the plasma heating taking place in the upper and / or adjoining central region of the fluidized bed and producing and maintaining a zone with the highest temperature of the fluidized bed there.
  • the additional energy input by means of plasma heating makes it possible to significantly reduce the total energy input due to the energy transmission, which is predominantly carried out by radiation (due to the high temperature of the plasma gas). Because the plasma heating takes place in the upper and / or adjoining central region of the fluidized bed and there creates and maintains a zone with the highest temperature of the fluidized bed, the temperature can be kept relatively low just above the surface of the slag bath, and reoxidation of the reduced (and already melted) iron ore particles just before they pass through the slag bath.
  • DD-A-28 565 For steelmaking, it is known from DD-A-28 565 to treat suspended ore suspended ore by means of a plasma torch using an addition of reducing gases.
  • DD-A-28 565 does not relate to a method according to the type described at the outset, since a fluidized bed formed from carbon particles and an oxygen-containing carrier gas and through which the raw material particles pass is not provided.
  • carbon carriers in solid and / or liquid form are advantageously introduced into the flame area of the plasma heater.
  • a reduction in the total energy input by up to 50% is possible if between 50 and 70% pre-reduced iron ore particles are introduced into the fluidized bed as iron oxide-containing raw material particles and are reduced in the fluidized bed.
  • Carbon carriers in solid and / or liquid form are advantageously blown into the fluidized bed from below.
  • inert gas is expediently blown into the fluidized bed from below.
  • a plant for carrying out the method has a refractory-lined melting vessel, which has openings for the addition of carbon and iron oxide-containing raw material particles and openings for slag or melt tapping and openings for introducing the oxygen-containing carrier gas, and is characterized in that in height of the fluidized bed, plasma burners are used in the vessel wall, the plasma burners being arranged in the upper and / or middle height range of the space of the melting vessel filled by the fluidized bed.
  • Nozzles for carbon carriers in solid and / or liquid form are advantageously provided adjacent to the plasma burners in the flame area of the plasma burners.
  • the plasma torches are directed towards a central axis of the melting vessel and are arranged in a ring around the axis of the vessel, the plasma torches being provided one above the other in several planes.
  • the plasma torches are expediently pivotable, in particular horizontally and vertically pivotable.
  • a preferred embodiment of the system is characterized in that bottom nozzles are provided in the bottom of the melting vessel for the supply of a carbon carrier and / or of oxygen or an oxygen-containing gas and / or an inert gas.
  • Plasma torch 12 equipped with a closed arc, which can be designed as a direct current or alternating current burner, is used.
  • the plasma torches 12 are expediently provided in a ring shape in the side walls in one or more planes, it being particularly advantageous if they can be pivoted both vertically in the direction of the arrows 13 and horizontally.
  • a portion of the reducing gas that flows out through the opening 6 and is produced in the melting vessel 1 serves as the plasma-forming gas.
  • plasma-forming polyatomic gases and / or diatomic or monatomic inert gases can also be used.
  • nozzles 14 for supplying carbon carriers are provided on the side walls 9, 10 of the melting vessel 1, which introduce the carbon carriers, preferably solid or liquid carbon carriers, into the flame area of the plasma torch 12.
  • the oxygen-containing carrier gas which is used to generate the fluidized bed, is introduced into the melting vessel through gas nozzles 15, which are also arranged in the side walls of the melting vessel below the plasma torch. Both the nozzles 14 and the gas nozzles 15 can be pivoted to the same extent as the plasma torch.
  • a slag tap hole 16 is provided just below the gas nozzles 15.
  • a metal tap hole 18 is arranged in the vicinity of the bottom 17 of the melting vessel.
  • the floor itself has a few further nozzles 19 to 23, through which coal and / or coke dust 24, oxygen 25, inert gas 26, natural gas 27 or liquid carbon carrier 28 can be introduced into the melting vessel 1.
  • the function of the melting vessel is as follows: the pre-reduced iron ore 8 introduced from above, preferably in free fall, enters the fluidized bed 29, which extends from above the slag tap opening 16 to above the plasma torch 12, travels downwards, is heated, reduced and melted.
  • the molten metal 30 collects below the slag layer 31.
  • the reduction gas is generated by plasma heating of liquid and / or solid carbon carriers which are introduced into the flame area of the plasma torch 12 through the nozzles 14. Another heat input for the required process heat is obtained from the partial combustion of the carbon carriers used. This combined gasification, reduction and melting process can take place at normal pressure as well as at elevated pressure.
  • the carbon carriers introduced through the floor nozzles 19 to 23 (coal and / or coke dust, liquid hydrocarbons, natural gas, SNG - synthetic natural gas) and the gases introduced through the floor nozzles (oxygen and / or inert gas) are used to make corrections to the heat balance of the Fluidized bed and to stabilize the flow conditions.
  • oxygen and / or inert gas are used to make corrections to the heat balance of the Fluidized bed and to stabilize the flow conditions.
  • a major advantage of introducing energy into the combined gasification, reduction and melting process by means of plasma heating is the energy transfer that takes place primarily through radiation, which is caused by the high temperature (4,000 to 15,000 ° K) of the plasma gas.
  • the temperature just above the slag layer 31 can be kept relatively low, so that reoxidation of the already reduced iron ore can be avoided.
  • the likelihood of reoxidation in the upper or middle area of the fluidized bed is significantly lower than in the lower area of the fluidized bed and, if reoxidation does occur occasionally, this can occur in the area of the fluidized bed 29 below the high temperature zone, which area represents a compensation zone, so to speak , can be undone again.
  • Another advantage of the method according to the invention is the fact that the diameter of the melting vessel can be kept very large, which advantage through the bottom nozzles - due to the better vortexing of the Fluid bed - comes into play even more.
  • H The zone of highest temperature in the fluidized bed, due to the change in inclination of the plasma torch 12 and the nozzles 14 and 15, the various operating conditions can always be optimally taken into account.
  • B different flow velocities within the melting vessel or the respective height of the fluidized bed, which again depends on the particle size of the supplied ores and the supplied coke.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Manufacture Of Iron (AREA)
  • Catalysts (AREA)

Description

Die Erfindung betrifft ein Verfahren zur Herstellung von flüssigem Roheisen oder Stahlvormaterial aus eisenoxydhältigen Rohstoffpartikeln, insbesondere vorreduziertem Eisenerz, bei dem eisenoxydhältigen Rohstoffpartikel in ein aus Kohleteilchen und einem sauerstoffhältigen Trägergas gebildetes Wirbelbett von oben eingebracht und bei Durchwandern desselben erhitzt, reduziert und aufgeschmolzen werden, sowie eine Anlage zur Durchführung des Verfahrens.The invention relates to a process for the production of molten pig iron or steel raw material from iron oxide-containing raw material particles, in particular pre-reduced iron ore, in which iron oxide-containing raw material particles are introduced from above into a fluidized bed formed from coal particles and an oxygen-containing carrier gas and heated, reduced and melted during passage through the same, and one Plant for carrying out the process.

Bei den bisher bekannten Verfahren dieser Art (DE-C-1 246780) ist eine hohe Energieeinbringung notwendig, wobei jedoch die Energieausnützung nicht als optimal angesehen werden kann, so daß die Wärmebilanz und damit die Wirtschaftlichkeit der bekannten Verfahren nicht zufriedenstellend ist. Weiters ist es bei den bekannten Verfahren nicht möglich, das Wirbelbett in einem Gefäß mit großem Durchmesser aufrecht zu halten ; man ist vielmehr an verhältnismäßig kleine Gefäße mit geringem Durchmesser gebunden, was ebenfalls der Wirtschaftlichkeit abträglich ist.In the previously known methods of this type (DE-C-1 246780) a high energy input is necessary, but the energy utilization cannot be regarded as optimal, so that the heat balance and thus the economy of the known methods is unsatisfactory. Furthermore, it is not possible with the known methods to maintain the fluidized bed in a large-diameter vessel; one is rather bound to relatively small vessels with a small diameter, which is also detrimental to economy.

Die Einbringung des sauerstoffhältigen Trägergases muß knapp oberhalb der Schlackenbadoberfläche erfolgen, damit das Wirbelbett bis zu dieser Oberfläche reicht. Aus diesem Grund kommt es bei den bekannten Verfahren im unteren Bereich des Wirbelbettes, also knapp über der Schlackenbadoberfläche, zur Bildung einer Zone mit höchster Temperatur des Wirbelbettes (Hochtemperaturzone). Dies hat den Nachteil, daß in dieser Zone eine Reoxidation der bereits ausreduzierten Eisenerzpartikel nicht mit Sicherheit vermieden werden kann.The oxygen-containing carrier gas must be introduced just above the slag bath surface so that the fluidized bed reaches this surface. For this reason, in the known processes in the lower region of the fluidized bed, that is to say just above the slag bath surface, a zone with the highest temperature of the fluidized bed (high-temperature zone) is formed. This has the disadvantage that reoxidation of the iron ore particles which have already been reduced cannot be avoided with certainty in this zone.

Die Erfindung bezweckt die Vermeidung dieser Nachteile und Schwierigkeiten und stellt sich die Aufgabe, ein Verfahren der eingangs beschriebenen Art sowie eine Anlage zur Durchführung des Verfahrens zu schaffen, bei welchen unter wesentlich günstigerer Energieausnützung der Gesamtenergieeinsatz bedeutend abgesenkt werden kann, so daß der Reduktions- und Einschmelzungsprozeß wirtschaftlicher als bisher durchgeführt werden kann.The invention aims to avoid these disadvantages and difficulties and has the object to provide a method of the type described above and a system for carrying out the method in which the total energy use can be significantly reduced with much cheaper energy use, so that the reduction and Melting process can be carried out more economically than before.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß dem Wirbelbett durch Plasmaheizung zusätzlich Energie zugeführt wird, wobei die Plasmaheizung im oberen und/oder daran anschließenden mittleren Bereich des Wirbelbettes erfolgt und dort eine Zone mit höchster Temperatur des Wirbelbettes erzeugt und aufrechterhält.This object is achieved in that the fluidized bed is additionally supplied with energy by plasma heating, the plasma heating taking place in the upper and / or adjoining central region of the fluidized bed and producing and maintaining a zone with the highest temperature of the fluidized bed there.

Die zusätzliche Energieeinbringung durch Plasmaheizung ermöglicht es, infolge der vorwiegend durch Strahlung erfolgenden Energieübertragung (bedingt durch die hohe Temperatur des Plasmagases) den Gesamtenergieeinsatz bedeutend abzusenken. Dadurch, daß die Plasmaheizung im oberen und/oder daran anschließenden mittleren Bereich des Wirbelbettes erfolgt und dort eine Zone mit höchster Temperatur des Wirbelbettes erzeugt und aufrechterhält, kann die Temperatur knapp oberhalb der Schlackenbadoberfläche relativ niedrig gehalten werden, und eine Reoxidation der ausreduzierten (und bereits aufgeschmolzenen) Eisenerzpartikel knapp vor Durchtritt durch das Schlackenbad vermieden werden.The additional energy input by means of plasma heating makes it possible to significantly reduce the total energy input due to the energy transmission, which is predominantly carried out by radiation (due to the high temperature of the plasma gas). Because the plasma heating takes place in the upper and / or adjoining central region of the fluidized bed and there creates and maintains a zone with the highest temperature of the fluidized bed, the temperature can be kept relatively low just above the surface of the slag bath, and reoxidation of the reduced (and already melted) iron ore particles just before they pass through the slag bath.

Aus der DD-A-28 565 ist es zur Stahlerzeugung bekannt, in den Schwebezustand gebrachtes Feinerz mittels eines Plasmabrenners unter Verwendung eines Zusatzes von reduzierenden Gasen zu behandeln. Die DD-A-28 565 betrifft jedoch kein Verfahren gemäß der eingangs beschriebenen Art, da dort ein aus Kohleteilchen und einem sauerstoffhältigen Trägergas gebildetes Wirbelbett, welches von den Rohstoffpartikeln durchsetzt wird, nicht vorgesehen ist.For steelmaking, it is known from DD-A-28 565 to treat suspended ore suspended ore by means of a plasma torch using an addition of reducing gases. However, DD-A-28 565 does not relate to a method according to the type described at the outset, since a fluidized bed formed from carbon particles and an oxygen-containing carrier gas and through which the raw material particles pass is not provided.

Die Wirtschaftlichkeit des Verfahrens wird noch weiter erhöht, wenn als Plasma-bildendes Gas ein Teil des im Wirbelbett gebildeten Reduktionsgases verwendet wird.The economy of the process is further increased if part of the reducing gas formed in the fluidized bed is used as the plasma-forming gas.

Vorteilhaft werden in den Flammenbereich der Plasmaheizung zusätzlich Kohlenstoffträger in fester und/oder flüssiger Form eingebracht.In addition, carbon carriers in solid and / or liquid form are advantageously introduced into the flame area of the plasma heater.

Eine Absenkung des Gesamtenergieeinsatzes bis zu 50 % ist möglich, wenn als eisenoxydhältige Rohstoffpartikel zwischen 50 und 70 % vorreduzierte Eisenerzpartikel in das Wirbelbett eingebracht werden und im Wirbelbett ausreduziert werden.A reduction in the total energy input by up to 50% is possible if between 50 and 70% pre-reduced iron ore particles are introduced into the fluidized bed as iron oxide-containing raw material particles and are reduced in the fluidized bed.

Vorteilhaft werden Kohlenstoffträger in fester und/oder flüssiger Form von unten in das Wirbelbett eingeblasen.Carbon carriers in solid and / or liquid form are advantageously blown into the fluidized bed from below.

Es ist weiters von Vorteil, Sauerstoff bzw. sauerstoffhältige Gase von unten in das Wirbelbett einzublasen, wobei man als Endprodukt Stahlvormaterial gewinnen kann.It is also advantageous to blow oxygen or oxygen-containing gases into the fluidized bed from below, whereby the end product can be obtained as a steel raw material.

Zur Steuerung des Prozesses wird zweckmäßig Inertgas von unten in das Wirbelbett eingeblasen.To control the process, inert gas is expediently blown into the fluidized bed from below.

Eine Anlage zur Durchführung des Verfahrens weist ein feuerfest ausgekleidetes Schmelzgefäß auf, welches Öffnungen für die Zugabe von kohle-und eisenoxydhältiger Rohstoffpartikel und Öffnungen für den Schlacken- bzw. Schmelzenabstich sowie Öffnungen zum Einleiten des sauerstoffhältigen Trägergases aufweist, und ist dadurch gekennzeichnet, daß in Höhe des Wirbelbettes in der Gefäßwand Plasmabrenner eingesetzt sind, wobei die Plasmabrenner im oberen und/oder mittleren Höhenbereich des vom Wirbelbett ausgefüllten Raumes des Schmelzgefäßes angeordnet sind.A plant for carrying out the method has a refractory-lined melting vessel, which has openings for the addition of carbon and iron oxide-containing raw material particles and openings for slag or melt tapping and openings for introducing the oxygen-containing carrier gas, and is characterized in that in height of the fluidized bed, plasma burners are used in the vessel wall, the plasma burners being arranged in the upper and / or middle height range of the space of the melting vessel filled by the fluidized bed.

Vorteilhaft sind benachbart zu den Plasmabrennern in den Flammenbereich der Plasmabrenner gerichtete Düsen für Kohlenstoffträger in fester und/oder flüssiger Form vorgesehen.Nozzles for carbon carriers in solid and / or liquid form are advantageously provided adjacent to the plasma burners in the flame area of the plasma burners.

Nach einer bevorzugten Ausführungsform sind die Plasmabrenner in Richtung auf eine zentrale Achse des Schmelzgefäßes gerichtet und um die Achse des gefäßes ringförmig angeordnet, wobei die Plasmabrenner in mehreren Ebenen übereinander vorgesehen sind.According to a preferred embodiment, the plasma torches are directed towards a central axis of the melting vessel and are arranged in a ring around the axis of the vessel, the plasma torches being provided one above the other in several planes.

Um die Zone der maximal auftretenden Temperatur im Wirbelbett in ihrer Höhenlage und in ihrer Ausdehnung variieren zu können, sind zweckmäßig die Plasmabrenner schwenkbar, insbesondere horizontal und vertikal schwenkbar angeordnet.Around the zone of the maximum occurring tempe To be able to vary the height and extent of the fluid bed in the fluidized bed, the plasma torches are expediently pivotable, in particular horizontally and vertically pivotable.

Eine bevorzugte Ausführungsform der Anlage ist dadurch gekennzeichnet, daß im Boden des Schmelzgefäßes Bodendüsen für die Zuführung eines Kohlenstoffträgers und/oder von Sauerstoff bzw. eines sauerstoffhältigen Gases und/oder eines Inertgases vorgesehen sind.A preferred embodiment of the system is characterized in that bottom nozzles are provided in the bottom of the melting vessel for the supply of a carbon carrier and / or of oxygen or an oxygen-containing gas and / or an inert gas.

Die Erfindung ist nachfolgend anhand der Zeichnung näher erläutert :

  • Die Zeichnung zeigt ein Schmelzgefäß 1 in schematischer Darstellung im Schnitt, dessen Innenseite mit einer feuerfesten Auskleidung 2 versehen ist. An der Oberseite 3 des Gefäßes befinden sich drei Öffnungen 4, 5 und 6. Eine (5) der Öffnungen dient dazu, Kohle bzw. Koks, vorzugsweise nicht kokbare Kohle 7, unterschiedlicher Körnung, u. zw. feinkörnig bis stückig, in das Schmelzgefäß 1 einzubringen. Die zweite Öffnung 4 dient zur Aufgabe eisenoxydhältiger Rohstoffpartikel, wobei vorzugsweise 50 bis 70 % vorreduziertes Eisenerz 8 in das Schmelzgefäß eingebracht wird. Durch die weiters an der Oberseite des Schmelzgefäßes vorgesehene Öffnung 6 strömt Reduktionsgas, welches zum Vorreduzieren des Eisenerzes verwendet wird, aus dem Schmelzgefäß.
The invention is explained in more detail below with reference to the drawing:
  • The drawing shows a melting vessel 1 in a schematic representation in section, the inside of which is provided with a refractory lining 2. At the top 3 of the vessel there are three openings 4, 5 and 6. One (5) of the openings is used to coal or coke, preferably non-coking coal 7, different grain, u. between fine-grained to lumpy, to be introduced into the melting vessel 1. The second opening 4 serves to feed in raw material particles containing iron oxide, preferably 50 to 70% pre-reduced iron ore 8 being introduced into the melting vessel. Reducing gas, which is used to pre-reduce the iron ore, flows out of the melting vessel through the opening 6 also provided on the upper side of the melting vessel.

In die Seitenwände 9, 10 des Schmelzgefäßes 1 sind in Richtung zur Achse 11 des Schmelzgefäßes 1 gerichtete indirekte, d. h. mit geschlossenem Lichtbogen ausgestattete Plasmabrenner 12, die als Gleichstrom- oder Wechselstrombrenner ausgeführt sein können, eingesetzt. Die Plasmabrenner 12 sind zweckmäßig ringförmig in den Seitenwänden in einer oder mehreren Ebenen vorgesehen, wobei es von besonderem Vorteil ist, wenn sie sowohl vertikal in Richtung der Pfeile 13 als auch horizontal schwenkbar sind. Als Plasma-bildendes Gas dient ein Teil des durch die Öffnung 6 ausströmenden, im Schmelzgefäß 1 entstandenen Reduktionsgases. Es können aber auch Plasma-bildende mehratomige Gase und/ oder zwei- oder einatomige Inertgase verwendet werden. Unterhalb der Plasmabrenner 12 sind an den Seitenwänden 9, 10 des Schmelzgefäßes 1 Düsen 14 zur Zufuhr von Kohlenstoffträgern vorgesehen, die die Kohlenstoffträger, vorzugsweize feste oder flüssige Kohlenstoffträger, in den Flammenbereich der Plasmabrenner 12 einbringen. Das sauerstoffhältige Trägergas, welches zur Erzeugung des Wirbelbettes dient, wird durch Gasdüsen 15, die ebenfalls in den Seitenwänden des Schmelzgefäßes unterhalb der Plasmabrenner angeordnet sind, in das Schmelzgefäß eingeleitet. Sowohl die Düsen 14 als auch die Gasdüsen 15 sind in etwa gleichem Ausmaß wie die Plasmabrenner schwenkbar. Knapp unterhalb der Gasdüsen 15 ist ein Schlackenabstichloch 16 vorgesehen. In der Nähe des Bodens 17 des Schmelzgefäßes ist ein Metallabstichloch 18 angeordnet. Der Boden selbst weist einige weitere Düsen 19 bis 23 auf, durch welche Kohle-und/oder Koksstaub 24, Sauerstoff 25, Inertgas 26, Erdgas 27 oder flüssige Kohlenstoffträger 28 in das Schmelzgefäß 1 eingeleitet werden können.In the side walls 9, 10 of the melting vessel 1 in the direction of the axis 11 of the melting vessel 1 directed indirect, d. H. Plasma torch 12 equipped with a closed arc, which can be designed as a direct current or alternating current burner, is used. The plasma torches 12 are expediently provided in a ring shape in the side walls in one or more planes, it being particularly advantageous if they can be pivoted both vertically in the direction of the arrows 13 and horizontally. A portion of the reducing gas that flows out through the opening 6 and is produced in the melting vessel 1 serves as the plasma-forming gas. However, plasma-forming polyatomic gases and / or diatomic or monatomic inert gases can also be used. Below the plasma torch 12, nozzles 14 for supplying carbon carriers are provided on the side walls 9, 10 of the melting vessel 1, which introduce the carbon carriers, preferably solid or liquid carbon carriers, into the flame area of the plasma torch 12. The oxygen-containing carrier gas, which is used to generate the fluidized bed, is introduced into the melting vessel through gas nozzles 15, which are also arranged in the side walls of the melting vessel below the plasma torch. Both the nozzles 14 and the gas nozzles 15 can be pivoted to the same extent as the plasma torch. A slag tap hole 16 is provided just below the gas nozzles 15. A metal tap hole 18 is arranged in the vicinity of the bottom 17 of the melting vessel. The floor itself has a few further nozzles 19 to 23, through which coal and / or coke dust 24, oxygen 25, inert gas 26, natural gas 27 or liquid carbon carrier 28 can be introduced into the melting vessel 1.

Die Funktion des Schmelzgefäßes ist folgende : Das von oben, vorzugsweise im freien Fall, eingebrachte vorreduzierte Eisenerz 8 gelangt in das sich von overhalb der Schlackenabstichöffnung 16 bis oberhalb der Plasmabrenner 12 erstreckende Wirbelbett 29, durchwandert dieses nach unten, wird in diesem erhitzt, ausreduziert und aufgeschmolzen. Die Metallschmelze 30 sammelt sich unterhalb der Schlackenschicht 31. Die Erzeugung des Reduktionsgases erfolgt gemäß dem dargestellten Ausführungsbeispiel durch Plasmaerhitzung von flüssigen und/oder festen Kohlenstoffträgern, die in .den Flammbereich der Plasmabrenner 12 durch die Düsen 14 eingebracht werden. Ein weiterer Wärmeeingang für die erforderliche Prozeßwärme wird aus der Teilverbrennung der eingesetzten Kohlenstoffträger gewonnen. Dieser kombinierte Vergasungs-, Reduktions- und Einschmelzungsprozeß kann sowohl bei normalem Druck als auch bei erhöhtem Druck erfolgen.The function of the melting vessel is as follows: the pre-reduced iron ore 8 introduced from above, preferably in free fall, enters the fluidized bed 29, which extends from above the slag tap opening 16 to above the plasma torch 12, travels downwards, is heated, reduced and melted. The molten metal 30 collects below the slag layer 31. According to the exemplary embodiment shown, the reduction gas is generated by plasma heating of liquid and / or solid carbon carriers which are introduced into the flame area of the plasma torch 12 through the nozzles 14. Another heat input for the required process heat is obtained from the partial combustion of the carbon carriers used. This combined gasification, reduction and melting process can take place at normal pressure as well as at elevated pressure.

Die durch die Bodendüsen 19 bis 23 eingebrachten Kohlenstoffträger (Kohle- und/oder Kokksstaub, flüssige Kohlenwasserstoffe, Erdgas, SNG -synthetic natural gas) und die durch die Bodendüsen eingebrachten Gase (Sauerstoff und/oder Inertgas) dienen zur Vornahme von Korrekturen der Wärmebilanz des Wirbelbettes und zur Stabilisierung der Strömungsbedingungen. Durch die Verwendung von Sauerstoff kann weiters ein Frischprozeß in dem Schmelzgefäß 1 zur Herstellung von Stahlvormaterial erfolgen.The carbon carriers introduced through the floor nozzles 19 to 23 (coal and / or coke dust, liquid hydrocarbons, natural gas, SNG - synthetic natural gas) and the gases introduced through the floor nozzles (oxygen and / or inert gas) are used to make corrections to the heat balance of the Fluidized bed and to stabilize the flow conditions. By using oxygen, a fresh process can also be carried out in the melting vessel 1 for the production of primary steel material.

Ein wesentlicher Vorteil der Energieeinbringung in den kombinierten Vergasungs-, Reduktions- und Einschmelzungsprozeß mittels Plasmaheizung besteht in der vorwiegend durch Strahlung erfolgenden Energieübertragung, die bedingt ist durch die hohe Temperatur (4 000 bis 15 000° K) des Plasmagases.A major advantage of introducing energy into the combined gasification, reduction and melting process by means of plasma heating is the energy transfer that takes place primarily through radiation, which is caused by the high temperature (4,000 to 15,000 ° K) of the plasma gas.

Dadurch daß die Zone höchster Temperatur im mittleren oder darüber befindlichen oberen Bereich des Wirbelbettes 29 erzeugt und aufrechterhalten wird, kann die Temperatur knapp oberhalb der Schlackenschicht 31 relativ niedrig gehalten werden, sodaß eine Reoxydation des bereits ausreduzierten Eisenerzes vermieden werden kann. Die Wahrscheinlichkeit einer Reoxydation im oberen bzw. mittleren Bereich des Wirbelbettes ist wesentlich geringer als im unteren Bereich des Wirbelbettes und außerdem kann, falls doch eine Reoxydation fallweise stattfindet, diese in dem unterhalb der Hochtemperaturzone liegenden Bereich des Wirbelbettes 29, welcher Bereich sozusagen eine Ausgleichszone darstellt, wieder rückgängig gemacht werden.Because the zone of highest temperature is generated and maintained in the middle or above the upper region of the fluidized bed 29, the temperature just above the slag layer 31 can be kept relatively low, so that reoxidation of the already reduced iron ore can be avoided. The likelihood of reoxidation in the upper or middle area of the fluidized bed is significantly lower than in the lower area of the fluidized bed and, if reoxidation does occur occasionally, this can occur in the area of the fluidized bed 29 below the high temperature zone, which area represents a compensation zone, so to speak , can be undone again.

Ein weiterer Vorteil des erfindungsgemäßen Verfahrens ist darin zu sehen, daß der Durchmesser des Schmelzgefäßes sehr groß gehalten werden kann, welcher Vorteil durch die Bodendüsen - infolge der besseren Durchwirbelung des Wirbelbettes - noch verstärkt zur Geltung kommt.Another advantage of the method according to the invention is the fact that the diameter of the melting vessel can be kept very large, which advantage through the bottom nozzles - due to the better vortexing of the Fluid bed - comes into play even more.

Durch eine Variation der Höhenlage bzw. der Ausdehnung der Hochtemperaturzone, d. h. der Zone höchster Temperatur im Wirbelbett, infolge Neigungsänderung der Plasmabrenner 12 und der Düsen 14 und 15, kann den verschiedenen Betriebsbedingungen stets optimal Rechnung getragen werden, so z. B. unterschiedlichen Strömungsgeschwindigkeiten innerhalb des Schmelzgefäßes oder der jeweiligen Höhe des Fließbettes, die wieder von der Teilchengröße der zugeführten Erze und des zugeführten Kokses abhängt.By varying the altitude or the extent of the high temperature zone, i.e. H. The zone of highest temperature in the fluidized bed, due to the change in inclination of the plasma torch 12 and the nozzles 14 and 15, the various operating conditions can always be optimally taken into account. B. different flow velocities within the melting vessel or the respective height of the fluidized bed, which again depends on the particle size of the supplied ores and the supplied coke.

Claims (14)

1. A method for producing molten pig iron (30) or steel pre-material from iron-oxide-containing raw-material particles, in particular pre-reduced iron ore (8), in which the iron-oxide-containing raw-material particles are top-charged into a fluidized bed (29) formed of carbon particles (7) and an oxygen-containing carrier gas and are heated, reduced and melted when passing through the same, characterized in that energy is additionally supplied to the fluidized bed (29) by plasma heating, the plasma heating being effected in the upper and/or central region following thereupon, of the fluidized bed, and a zone of maximum temperature of the fluidized bed being generated and maintained there.
2. A method according to claim 1, characterized in that part of the reduction gas formed in the fluidized bed is used as the plasma forming gas.
3. A method according to claim 1 or 2, characterized in that additional carbon carriers in solid and/or liquid form are charged into the flame region of the plasma heating.
4. A method according to claims 1 to 3, characterized in that, as the iron-oxide-containing raw-material particles, between 50 and 70 % of pre-reduced iron-ore particules are charged into the fluidized bed and are completely reduced in the fluidized bed.
5. A method according to ciaims 1 to 4, characterized in that carbon carriers in solid and/or liquid form are bottom-blown into the fluidized bed.
6. A method according to claims 1 to 5, characterized in that oxygen or oxygen-containing gases are bottom-blown into the fluidized bed.
7. A method according to claims 1 to 6, characterized in that inert gas is bottom-blown into the fluidized bed.
8. A plant for carrying out the method according to claims 1 to 7, comprising a refractorily lined melting vessel, which includes openings for adding carbon-containing and iron-oxide-containing raw-material particles and openings for tapping slag and melt as well as openings for introducing the oxygen-containing carrier gas, characterized in that plasma burners (12) are incorporated in the vessel wall at the height of the fluidized bed (29), the plasma bruners (12) being arranged in the upper and/or central height regions of the space of the melting vessel (1) filled with the fluidized bed (29).
9. A plant according to claim 8, characterized in that the plasma burners (12) are directed in the direction towards a central axis (11) of the melting vesssel (1).
10. A plant according to claim 8 or 9, characterized in that, in the vicinity of the plasma burners (12), nozzles (14) for carbon carriers in solid and/or liquid form are provided, which are directed into the flame region of the plasma burners (12).
11. A plant according to claims 8 to 10, characterized in that the plasma burners (12) are provided in an annular disposition about the axis (11) of the melting vessel (1).
12. A plant according to claims 8 to 11, characterized in that the plasma burners (12) are arranged in several levels one above the other.
13. A plant according to claims 8 to 12, characterized in that the plasma burners (12) are arranged to be pivotable, in particular horizontally and vertically pivotable.
14. A plant according to claims 8 to 13, characterized in that, in the bottom of the melting vessel, bottom nozzles are provided for supplying a carbon carrier and/or oxygen or an oxygen-containing gas and/or an inert gas.
EP81890058A 1980-04-03 1981-04-02 Method of and arrangement for producing molten pig iron or steel prematerial Expired EP0037809B1 (en)

Applications Claiming Priority (2)

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AT0182880A AT367453B (en) 1980-04-03 1980-04-03 METHOD AND DEVICE FOR PRODUCING LIQUID GUT IRON OR STEEL PRE-MATERIAL
AT1828/80 1980-04-03

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EP0037809B1 true EP0037809B1 (en) 1985-08-28

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EP (1) EP0037809B1 (en)
JP (1) JPS56156708A (en)
AT (1) AT367453B (en)
AU (1) AU537907B2 (en)
BR (1) BR8102003A (en)
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DE (1) DE3171978D1 (en)
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NO (1) NO153144C (en)
PH (1) PH18456A (en)
PL (1) PL130491B1 (en)
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ZA (1) ZA812222B (en)

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EP0087405A1 (en) * 1982-01-19 1983-08-31 VOEST-ALPINE Aktiengesellschaft Process and device for the reduction of particle-sized ores containing oxide
EP0182775A2 (en) * 1984-11-15 1986-05-28 VOEST-ALPINE INDUSTRIEANLAGENBAU GESELLSCHAFT m.b.H. Process for the production of molten pig iron or steel pre-products as well as arrangement for carrying out the process
EP0189368A2 (en) * 1985-01-21 1986-07-30 Deutsche Voest-Alpine Industrieanlagenbau Gmbh Process for making pig iron
DE3603894A1 (en) * 1986-02-05 1987-08-06 Korf Engineering Gmbh METHOD FOR PRODUCING LIQUID PIPE IRON OR STEEL PRE-MATERIAL
EP0319836A1 (en) * 1987-12-10 1989-06-14 Deutsche Voest-Alpine Industrieanlagenbau Gmbh Method and apparatus for operating a melting gasifier

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AT378970B (en) * 1982-12-21 1985-10-25 Voest Alpine Ag METHOD AND DEVICE FOR THE PRODUCTION OF LIQUID PIPE IRON OR STEEL PRE-PRODUCTS
AT382595B (en) * 1982-12-22 1987-03-10 Sueddeutsche Kalkstickstoff PLANT FOR THE PRODUCTION OF CALCIUM CARBIDE
IN164687B (en) * 1984-08-16 1989-05-13 Voest Alpine Ag
SE453304B (en) * 1984-10-19 1988-01-25 Skf Steel Eng Ab KIT FOR MANUFACTURE OF METALS AND / OR GENERATION OF BATTLE FROM OXIDE ORE
DE3535572A1 (en) * 1985-10-03 1987-04-16 Korf Engineering Gmbh METHOD FOR PRODUCING HARD IRON FROM FINE ORE
US4654076A (en) * 1986-01-30 1987-03-31 Plasma Energy Corporation Apparatus and method for treating metallic fines
US4936908A (en) * 1987-09-25 1990-06-26 Nkk Corporation Method for smelting and reducing iron ores
DK158382C (en) * 1987-10-15 1990-10-22 Rockwool Int PROCEDURE FOR PREPARING A MELT FOR THE FORMATION OF MINERAL WOOL AND APPARATUS FOR EXERCISING THE PROCEDURE
US6197088B1 (en) 1992-10-06 2001-03-06 Bechtel Group, Inc. Producing liquid iron having a low sulfur content
US5397376A (en) * 1992-10-06 1995-03-14 Bechtel Group, Inc. Method of providing fuel for an iron making process
US5320676A (en) * 1992-10-06 1994-06-14 Bechtel Group, Inc. Low slag iron making process with injecting coolant
US5338336A (en) * 1993-06-30 1994-08-16 Bechtel Group, Inc. Method of processing electric arc furnace dust and providing fuel for an iron making process
US5380352A (en) * 1992-10-06 1995-01-10 Bechtel Group, Inc. Method of using rubber tires in an iron making process
US5958107A (en) * 1993-12-15 1999-09-28 Bechtel Croup, Inc. Shift conversion for the preparation of reducing gas
AT404362B (en) * 1996-12-17 1998-11-25 Voest Alpine Ind Anlagen METHOD AND MELTING CARBURETOR FOR PRODUCING LIQUID METAL
SE1250215A1 (en) 2012-03-08 2013-08-06 Valeas Recycling Ab Iron reduction process and device therefore
WO2014119612A1 (en) * 2013-01-31 2014-08-07 住友重機械工業株式会社 Fluidized bed combustion furnace and method for operating fluidized bed combustion furnace

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0087405A1 (en) * 1982-01-19 1983-08-31 VOEST-ALPINE Aktiengesellschaft Process and device for the reduction of particle-sized ores containing oxide
EP0182775A2 (en) * 1984-11-15 1986-05-28 VOEST-ALPINE INDUSTRIEANLAGENBAU GESELLSCHAFT m.b.H. Process for the production of molten pig iron or steel pre-products as well as arrangement for carrying out the process
EP0182775A3 (en) * 1984-11-15 1986-09-03 Aktiengesellschaft Voest-Alpine Process for the production of molten pig iron or steel pre-products as well as arrangement for carrying out the process
EP0189368A2 (en) * 1985-01-21 1986-07-30 Deutsche Voest-Alpine Industrieanlagenbau Gmbh Process for making pig iron
EP0189368A3 (en) * 1985-01-21 1986-11-05 Korf Engineering Gmbh Process for making pig iron
DE3603894A1 (en) * 1986-02-05 1987-08-06 Korf Engineering Gmbh METHOD FOR PRODUCING LIQUID PIPE IRON OR STEEL PRE-MATERIAL
EP0236669A1 (en) * 1986-02-05 1987-09-16 Deutsche Voest-Alpine Industrieanlagenbau Gmbh Method for producing molten pig iron or steel pre-material
EP0319836A1 (en) * 1987-12-10 1989-06-14 Deutsche Voest-Alpine Industrieanlagenbau Gmbh Method and apparatus for operating a melting gasifier

Also Published As

Publication number Publication date
FI68264B (en) 1985-04-30
AU537907B2 (en) 1984-07-19
ES8302102A1 (en) 1982-12-16
FI811014L (en) 1981-10-04
DE3171978D1 (en) 1985-10-03
AU6907181A (en) 1981-10-08
ATA182880A (en) 1981-11-15
NO811138L (en) 1981-10-05
ES508210A0 (en) 1982-12-16
US4396421A (en) 1983-08-02
FI68264C (en) 1985-08-12
DD157915A5 (en) 1982-12-15
NO153144C (en) 1986-01-22
JPS56156708A (en) 1981-12-03
AT367453B (en) 1982-07-12
ES501074A0 (en) 1982-06-01
BR8102003A (en) 1981-10-06
SU1118292A3 (en) 1984-10-07
EP0037809A1 (en) 1981-10-14
CA1160056A (en) 1984-01-10
NO153144B (en) 1985-10-14
PL130491B1 (en) 1984-08-31
ES8205266A1 (en) 1982-06-01
PL230508A1 (en) 1981-12-23
PH18456A (en) 1985-07-18
ZA812222B (en) 1982-06-30

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