WO1998017830A1 - Method for producing steel from iron sponges in an induction furnace - Google Patents
Method for producing steel from iron sponges in an induction furnace Download PDFInfo
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- WO1998017830A1 WO1998017830A1 PCT/BE1997/000091 BE9700091W WO9817830A1 WO 1998017830 A1 WO1998017830 A1 WO 1998017830A1 BE 9700091 W BE9700091 W BE 9700091W WO 9817830 A1 WO9817830 A1 WO 9817830A1
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- liquid slag
- liquid
- steel
- iron
- sponges
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Classifications
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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
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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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
- C21C5/5241—Manufacture of steel in electric furnaces in an inductively heated furnace
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Definitions
- the present invention relates to a method for producing liquid steel from pre-reduced iron ores, also called iron sponges, in an induction furnace.
- iron sponges constitute a more advantageous charge for electric ovens than scrap iron. These materials indeed contain much less undesirable elements, such as for example sulfur and zinc, than scrap, and in addition the content of these elements is much more regular and therefore more controllable in steel. From an economic point of view also, iron sponges are generally advantageous because their price is not only more constant, but also often lower than that of scrap.
- arc furnaces At present, most of the world's steel production by electric means is provided by arc furnaces.
- the electrical efficiency of these arc furnaces is usually between 70% and 80%.
- induction furnaces are generally used to melt electrically conductive materials, such as metals, and in particular scrap metal; in known processes, the scrap itself constitutes the armature, which is the seat of heating leading to the melting of metallic materials.
- the efficiency depends on the resistivity of both the inductor and the load to be melted.
- the charge consists of a metal that conducts electricity well, such as copper
- the yield is around 50%; in the case of iron, this yield can reach 70%.
- the efficiency can practically reach 100%.
- the object of the present invention is to provide a method which makes it possible to produce liquid steel in an induction melting furnace, while benefiting from the high electrical yields attached to materials which do not conduct electricity.
- a method for producing liquid steel from iron sponges in which said iron sponges are charged in an induction furnace, is characterized in that a liquid slag is used as the armature .
- said liquid slag consists essentially of materials originating from the gangue which remain in the iron sponges.
- correcting agents such as reducing agents, dephosphorants and / or desulfurizers; these agents are intended to perfect the reduction of iron oxides and to allow other operations such as dephosphoration and / or desulfurization of iron.
- a liquid slag bath is formed in the zone of the furnace where the magnetic field prevails, the temperature of said liquid slag bath is maintained by induction above the melting point of said iron sponges, said iron sponges in contact with said liquid slag bath, essentially outside the zone where the magnetic field prevails, said iron sponges are fused by heat exchange with said liquid slag bath, the final oxides of iron, the steel obtained is separated from the liquid slag and the steel and the liquid slag are collected separately.
- the iron sponges are advantageously loaded hot in the induction furnace.
- the temperature level of the pre-reduced products at the inlet of the oven does not present any technological disadvantage, since no sensitive equipment of the oven is generally located nearby. This temperature can exceed 1000 ° C, even 1300 ° C, with the advantage of energy savings as mentioned above.
- the loading of iron sponges is essentially continuous, but can also be done by discrete loads.
- the solid iron sponges melt thanks to the heat which is transmitted to them by the liquid slag constituting the armature.
- the molten prereduced materials form droplets which are entrained by the forces of induction and gravity; they undergo a final reduction, as well as possibly a dephosphorization and / or a desulfurization by reaction with the liquid slag bath, and decant down the furnace. These reactions are governed in particular by the composition of the filler as well as by the temperature of the bath and of the additions.
- the liquid steel thus obtained flows out from the bottom of the induction furnace and the slag generated during the operation is discharged separately, for example by a separate orifice or by a dam weir located at the top. from the oven. Slag and / or steel can be discharged continuously or discontinuously.
- the generation of thermal energy by induction in the liquid slag is done with a coupling efficiency between the inductor (copper turns) and the armature (liquid slag) greater than 99%.
- the necessary frequency remains within the limits where the use of semiconductors is current practice, for example of the order of 10 kHz; it is therefore possible to use a simpler installation, the efficiency of which, from the supply network to the inductor, is of the order of 95%.
- the correcting agent added to the liquid slag bath consists essentially of calcium carbide.
- This substance has four important advantages for the process of the invention: - it offers a very high reduction potential, which makes it possible to ensure good reduction of the iron oxides present in the liquid slag; - After reacting, it forms CaO, a basic constituent allowing better dephosphorization and desulfurization of the steel;
- This variant does not however exclude the use of other reducing agents, such as carbon, coal, liquid or gaseous hydrocarbons.
- the liquid steel thus produced can be treated according to the traditional methods of ladle metallurgy.
- Steel can also be cast directly, either continuously or discontinuously.
- the timing of the start of the casting of the steel or the setting of the steel flow during the casting is made on the basis of the measurement of the current flowing through the inductor. This adjustment consists in starting the casting, in the case of a batch discharge, or in increasing the flow rate, in the case of a continuous casting, when this current exceeds a predetermined value.
- the liquid metal which settles at the bottom of the induction furnace solidifies superficially on contact with the wall which is suitably cooled, and can be extracted into a continuous ingot of desired shape, for example in the form of a slab. or billet.
- the bottom of the induction melting furnace communicates with a second very low power induction furnace, which can serve either as an intermediate steel tank, or to compensate for heat losses and to adjust the final temperature of the steel is yet to adjust the level of slag in the first furnace.
- the second induction furnace is subjected to a controlled vacuum, which makes it possible to adjust the level of liquid slag in the first melting furnace, while accumulating variable amounts of steel, and to maintain the steel produced under a vacuum allowing its degassing. It is not beyond the scope of the present invention to apply the aforementioned operations of ladle metallurgy treatment and / or casting to the steel collected in said second induction furnace.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
The iron sponges are loaded in the induction furnace, in which a liquid slag is used as armature. This liquid slag is essentially made up of matters derived from the lode stuff which subsist in the iron sponges. In particular a liquid slag bath is formed in the zone of the furnace where prevails a magnetic field, and the temperature of the liquid slag bath is maintained by induction above the melting point of the iron sponges. The iron sponges are contacted with the liquid slag bath, essentially outside the zone where the magnetic field prevails. The said iron sponges are melted by heat exchange with the liquid slag bath, and the final reduction of the iron oxides is carried out, as well as the optional dephosphorization and/or desulphurization of the liquid metal. The steel obtained is then separated from the liquid slag and the liquid steel and liquid slag are collected separately.
Description
PROCEDE DE PRODUCTION D'ACIER A PARTIR D'EPONGES DE FER DANS UN FOUR A INDUCTIONPROCESS FOR PRODUCING STEEL FROM IRON SPONGES IN AN INDUCTION OVEN
La présente invention concerne un procédé pour produire de l'acier liquide à partir de minerais de fer préréduits, appelés aussi éponges de fer, dans un four à induction.The present invention relates to a method for producing liquid steel from pre-reduced iron ores, also called iron sponges, in an induction furnace.
On sait que les éponges de fer constituent, pour les fours électriques, une charge plus intéressante que les ferrailles. Ces matières contiennent en effet beaucoup moins d'éléments indésirables, comme par exemple le soufre et le zinc, que les ferrailles, et en outre la teneur de ces éléments est beaucoup plus régulière et donc plus contrôlable dans l'acier. Au point de vue économique également, les éponges de fer sont généralement avantageuses parce que leur prix est non seulement plus constant, mais aussi souvent plus faible que celui des ferrailles.We know that iron sponges constitute a more advantageous charge for electric ovens than scrap iron. These materials indeed contain much less undesirable elements, such as for example sulfur and zinc, than scrap, and in addition the content of these elements is much more regular and therefore more controllable in steel. From an economic point of view also, iron sponges are generally advantageous because their price is not only more constant, but also often lower than that of scrap.
Il est bien connu aussi que le chargement d'épongés de fer chaudes permet d'économiser des quantités appréciables d'énergie électrique lors de leur fusion. Cette façon de procéder est particulièrement intéressante dans le cas où l'unité de production des préréduits se trouve à proximité immédiate du four électrique de fusion. Si ce n'est pas le cas, il peut néanmoins s'avérer intéressant de préchauffer les matières préréduites, dans les conditions requises, en utilisant une énergie moins chère que l'électricité. Il est clair que plus la température d'enfournement des produits préréduits est élevée et plus l'économie d'énergie électrique est grande. Les procédés classiques de production d'épongés de fer ne permettent guère de dépasser des températures de l'ordre de 1000°C.It is also well known that loading hot iron sponges saves appreciable amounts of electrical energy during their melting. This procedure is particularly advantageous in the case where the pre-reduced production unit is in the immediate vicinity of the electric melting furnace. If this is not the case, it may nevertheless prove to be advantageous to preheat the pre-reduced materials, under the required conditions, using cheaper energy than electricity. It is clear that the higher the charging temperature of the pre-reduced products, the greater the saving in electrical energy. Conventional methods for producing iron sponges hardly allow temperatures of the order of 1000 ° C. to be exceeded.
A l'heure actuelle, la plus grande partie de la production mondiale d'acier par la voie électrique est assurée par des fours à arc. Le rendement électrique de ces fours à arc est habituellement compris entre 70 % et 80 %.At present, most of the world's steel production by electric means is provided by arc furnaces. The electrical efficiency of these arc furnaces is usually between 70% and 80%.
On connaît par ailleurs des procédés de fusion par induction électrique. Dans le secteur de la métallurgie, les fours à induction sont généralement utilisés pour fondre des matières conductrices de l'électricité, telles que des métaux, et en particulier des
ferrailles; dans les procédés connus, les ferrailles constituent elles-mêmes l' induit, qui est le siège de échauffement conduisant à la fusion des matières métalliques.Furthermore, methods of fusion by electric induction are known. In the metallurgy sector, induction furnaces are generally used to melt electrically conductive materials, such as metals, and in particular scrap metal; in known processes, the scrap itself constitutes the armature, which is the seat of heating leading to the melting of metallic materials.
Dans le cas d'un four à induction, le rendement dépend de la résistivité tant de l'inducteur que de la charge à fondre. Lorsque la charge est constituée par un métal bon conducteur de l'électricité comme le cuivre, le rendement est d'environ 50 %; dans le cas du fer, ce rendement peut atteindre 70 % . Pour des matériaux moins bons conducteurs de l'électricité, comme par exemple les verres fondus, le rendement peut pratiquement atteindre 100 %.In the case of an induction furnace, the efficiency depends on the resistivity of both the inductor and the load to be melted. When the charge consists of a metal that conducts electricity well, such as copper, the yield is around 50%; in the case of iron, this yield can reach 70%. For materials that are less good conductors of electricity, such as for example molten glass, the efficiency can practically reach 100%.
La présente invention a pour objet de proposer un procédé qui permet de produire de l'acier liquide dans un four de fusion par induction, tout en bénéficiant des rendements électriques élevés attachés aux matières non conductrices de l'électricité.The object of the present invention is to provide a method which makes it possible to produce liquid steel in an induction melting furnace, while benefiting from the high electrical yields attached to materials which do not conduct electricity.
Conformément à l'invention, un procédé de production d'acier liquide à partir d'épongés de fer, dans lequel on charge lesdites éponges de fer dans un four à induction, est caractérisé en ce que l'on utilise comme induit une scorie liquide.According to the invention, a method for producing liquid steel from iron sponges, in which said iron sponges are charged in an induction furnace, is characterized in that a liquid slag is used as the armature .
Selon une variante particulière, ladite scorie liquide est essentiellement constituée par des matières provenant de la gangue qui subsistent dans les éponges de fer.According to a particular variant, said liquid slag consists essentially of materials originating from the gangue which remain in the iron sponges.
Il s'est également avéré avantageux d'y ajouter de faibles quantités d'agents correcteurs, tels que des agents réducteurs, déphosphorants et/ou désulfurants; ces agents sont destinés à parfaire la réduction des oxydes de fer et à permettre d'autres opérations telles que la déphosphoration et/ou la désulfuration du fer.It has also been found advantageous to add small amounts of correcting agents, such as reducing agents, dephosphorants and / or desulfurizers; these agents are intended to perfect the reduction of iron oxides and to allow other operations such as dephosphoration and / or desulfurization of iron.
Suivant une mise en oeuvre particulière, on forme un bain de scorie liquide dans la zone du four où règne le champ magnétique, on maintient par induction la température dudit bain de scorie liquide au-dessus du point de fusion desdites éponges de fer, on met lesdites éponges de fer en contact avec ledit bain de scorie liquide, essentiellement hors de la zone où règne le champ magnétique, on assure la fusion desdites éponges de fer par échange thermique avec ledit bain de scorie liquide, on effectue la réduction finale des oxydes de fer, on sépare l'acier obtenu de la scorie liquide et on recueille séparément l'acier et la scorie liquides.
Les éponges de fer sont avantageusement chargées à chaud dans le four à induction. Le niveau de température des produits préréduits à l'entrée du four ne présente aucun inconvénient d'ordre technologique, car aucun équipement sensible du four ne se trouve généralement à proximité. Cette température peut dépasser 1000°C, voire 1 300°C, avec l'avantage d'une économie d'énergie comme on l'a rappelé plus haut. Le chargement de éponges de fer se fait essentiellement en continu, mais peut aussi être fait par charges discrètes.According to a particular implementation, a liquid slag bath is formed in the zone of the furnace where the magnetic field prevails, the temperature of said liquid slag bath is maintained by induction above the melting point of said iron sponges, said iron sponges in contact with said liquid slag bath, essentially outside the zone where the magnetic field prevails, said iron sponges are fused by heat exchange with said liquid slag bath, the final oxides of iron, the steel obtained is separated from the liquid slag and the steel and the liquid slag are collected separately. The iron sponges are advantageously loaded hot in the induction furnace. The temperature level of the pre-reduced products at the inlet of the oven does not present any technological disadvantage, since no sensitive equipment of the oven is generally located nearby. This temperature can exceed 1000 ° C, even 1300 ° C, with the advantage of energy savings as mentioned above. The loading of iron sponges is essentially continuous, but can also be done by discrete loads.
Dans le four, les éponges de fer solides fondent grâce à la chaleur qui leur est transmise par la scorie liquide constituant l'induit. Les matières préréduites fondues forment des gouttelettes qui sont entraînées par les forces d'induction et de gravité; elles subissent une réduction finale, ainsi qu'éventuellement une déphosphoration et/ou une désulfuration par réaction avec le bain de scorie liquide, et décantent vers le bas du four. Ces réactions sont régies notamment par la composition de la charge ainsi que par la température du bain et des ajouts. L'acier liquide ainsi obtenu s'écoule par le bas du four à induction et la scorie générée au fur et à mesure de l'opération est évacuée séparément, par exemple par un orifice distinct ou par un déversoir à barrage situé à la partie supérieure du four. La scorie et/ou l'acier peuvent être évacués en continu ou en discontinu.In the oven, the solid iron sponges melt thanks to the heat which is transmitted to them by the liquid slag constituting the armature. The molten prereduced materials form droplets which are entrained by the forces of induction and gravity; they undergo a final reduction, as well as possibly a dephosphorization and / or a desulfurization by reaction with the liquid slag bath, and decant down the furnace. These reactions are governed in particular by the composition of the filler as well as by the temperature of the bath and of the additions. The liquid steel thus obtained flows out from the bottom of the induction furnace and the slag generated during the operation is discharged separately, for example by a separate orifice or by a dam weir located at the top. from the oven. Slag and / or steel can be discharged continuously or discontinuously.
La génération d'énergie thermique par induction dans la scorie liquide se fait avec un rendement de couplage entre l'inducteur (spires en cuivre) et l'induit (la scorie liquide) supérieur à 99 %. La fréquence nécessaire reste dans les limites où l'utilisation de semiconducteurs est la pratique actuelle, par exemple de l'ordre de 10 kHz; il est dès lors possible d'utiliser une installation plus simple et dont le rendement, depuis le réseau d'alimentation jusqu'à l'inducteur, est de l'ordre de 95 %.The generation of thermal energy by induction in the liquid slag is done with a coupling efficiency between the inductor (copper turns) and the armature (liquid slag) greater than 99%. The necessary frequency remains within the limits where the use of semiconductors is current practice, for example of the order of 10 kHz; it is therefore possible to use a simpler installation, the efficiency of which, from the supply network to the inductor, is of the order of 95%.
Suivant une caractéristique supplémentaire du procédé de l'invention, l'agent correcteur ajouté au bain de scorie liquide est essentiellement constitué par du carbure de calcium.According to an additional characteristic of the process of the invention, the correcting agent added to the liquid slag bath consists essentially of calcium carbide.
Cette substance présente quatre avantages importants pour le procédé de l'invention: - elle offre un potentiel de réduction très élevé, qui permet d'assurer une bonne réduction des oxydes de fer présents dans la scorie liquide;
- après avoir réagi, elle forme du CaO, constituant basique permettant une meilleure déphosphoration et désulfuration de l'acier;This substance has four important advantages for the process of the invention: - it offers a very high reduction potential, which makes it possible to ensure good reduction of the iron oxides present in the liquid slag; - After reacting, it forms CaO, a basic constituent allowing better dephosphorization and desulfurization of the steel;
- après avoir réagi, elle forme également du CO, qui fait mousser la scorie et améliore la cinétique des réactions; ce gaz réducteur est en outre utilisé dans l'installation de production des éponges de fer;- after reacting, it also forms CO, which lathers the slag and improves the kinetics of the reactions; this reducing gas is also used in the installation for producing iron sponges;
- elle n'est pas coûteuse.- it is not expensive.
Cette variante n'exclut cependant pas l'utilisation d'autres agents réducteurs, comme le carbone, le charbon, les hydrocarbures liquides ou gazeux.This variant does not however exclude the use of other reducing agents, such as carbon, coal, liquid or gaseous hydrocarbons.
L'acier liquide ainsi produit peut être traité suivant les méthodes traditionnelles de la métallurgie en poche.The liquid steel thus produced can be treated according to the traditional methods of ladle metallurgy.
L'acier peut aussi être coulé directement, soit en continu soit de façon discontinue. Le réglage du moment du début de la coulée de l'acier ou le réglage du débit de l'acier pendant la coulée se fait sur base de la mesure du courant qui traverse l'inducteur. Ce réglage consiste à commencer la coulée, dans le cas d'une évacuation en discontinu, ou à augmenter le débit de coulée, dans le cas d'une coulée continue, lorsque ce courant dépasse une valeur prédéterminée.Steel can also be cast directly, either continuously or discontinuously. The timing of the start of the casting of the steel or the setting of the steel flow during the casting is made on the basis of the measurement of the current flowing through the inductor. This adjustment consists in starting the casting, in the case of a batch discharge, or in increasing the flow rate, in the case of a continuous casting, when this current exceeds a predetermined value.
Suivant une caractéristique du procédé, le métal liquide qui décante au fond du four à induction se solidifie superficiellement au contact de la paroi qui est refroidie de façon appropriée, et peut être extrait en un lingot continu de forme désirée, par exemple en forme de brame ou de billette.According to one characteristic of the process, the liquid metal which settles at the bottom of the induction furnace solidifies superficially on contact with the wall which is suitably cooled, and can be extracted into a continuous ingot of desired shape, for example in the form of a slab. or billet.
Dans une variante du procédé, le fond du four de fusion à induction communique avec un second four à induction de très faible puissance, qui peut servir soit de réservoir intermédiaire d'acier, soit à compenser les pertes thermiques et à ajuster la température finale de l'acier soit encore à régler le niveau de la scorie dans le premier four.In a variant of the process, the bottom of the induction melting furnace communicates with a second very low power induction furnace, which can serve either as an intermediate steel tank, or to compensate for heat losses and to adjust the final temperature of the steel is yet to adjust the level of slag in the first furnace.
Dans une autre variante avantageuse, le second four à induction est soumis à une dépression contrôlée, ce qui permet de régler le niveau de scorie liquide dans le premier four de fusion, tout en accumulant des quantités variables d'acier, et à maintenir l'acier produit sous une dépression permettant son dégazage.
Il ne sort pas du cadre de la présente invention d'appliquer les opérations précitées de traitement de métallurgie en poche et/ou de coulée à l'acier recueilli dans ledit second four à induction.
In another advantageous variant, the second induction furnace is subjected to a controlled vacuum, which makes it possible to adjust the level of liquid slag in the first melting furnace, while accumulating variable amounts of steel, and to maintain the steel produced under a vacuum allowing its degassing. It is not beyond the scope of the present invention to apply the aforementioned operations of ladle metallurgy treatment and / or casting to the steel collected in said second induction furnace.
Claims
1 . Procédé de production d'acier liquide à partir d'épongés de fer, dans lequel on charge lesdites éponges de fer dans un four à induction, caractérisé en ce que l'on utilise comme induit une scorie liquide.1. Process for the production of liquid steel from iron sponges, in which said iron sponges are charged in an induction furnace, characterized in that a liquid slag is used as the induced material.
2. Procédé suivant la revendication 1 , caractérisé en ce que ladite scorie liquide est essentiellement constituée par des matières provenant de la gangue qui subsistent dans les éponges de fer.2. Method according to claim 1, characterized in that said liquid slag consists essentially of materials from the gangue which remain in the iron sponges.
3. Procédé suivant l'une ou l'autre des revendications 1 et 2, caractérisé en ce que l'on ajoute à ladite scorie liquide de faibles quantités d'agents correcteurs, tels que des agents réducteurs, déphosphorants et/ou désulfurants.3. Method according to either of claims 1 and 2, characterized in that small amounts of correcting agents, such as reducing agents, dephosphorous and / or desulfurizers, are added to said liquid slag.
4. Procédé suivant l'une ou l'autre des revendications précédentes, caractérisé en ce que l'on forme un bain de scorie liquide dans la zone du four où règne le champ magnétique, en ce que l'on maintient par induction la température dudit bain de scorie liquide au-dessus du point de fusion desdites éponges de fer, en ce que l'on met lesdites éponges de fer en contact avec ledit bain de scorie liquide, essentiellement hors de la zone où règne le champ magnétique, en ce que l'on assure la fusion desdites éponges de fer par échange thermique avec ledit bain de scorie liquide, en ce que l'on effectue la réduction finale des oxydes de fer, en ce que l'on sépare l'acier obtenu de la scorie liquide et en ce que l'on recueille séparément l'acier et la scorie liquides.4. Method according to either of the preceding claims, characterized in that a liquid slag bath is formed in the zone of the furnace where the magnetic field prevails, in that the temperature is maintained by induction of said liquid slag bath above the melting point of said iron sponges, in that said iron sponges are brought into contact with said liquid slag bath, essentially outside the zone where the magnetic field prevails, in this that the said iron sponges are melted by heat exchange with the said liquid slag bath, in that the final reduction of the iron oxides is carried out, in that the steel obtained is separated from the slag liquid and in that the liquid steel and slag are collected separately.
5. Procédé suivant l'une ou l'autre des revendications 3 et 4, caractérisé en ce que ledit agent correcteur est essentiellement constitué par du carbure de calcium.5. Method according to either of claims 3 and 4, characterized in that said corrective agent consists essentially of calcium carbide.
6. Procédé suivant l'une ou l'autre des revendications 1 à 5, caractérisé en ce que l'on transfère ledit acier dans un second four à induction avant son traitement ultérieur.6. Method according to either of claims 1 to 5, characterized in that said steel is transferred to a second induction furnace before its further treatment.
7. Procédé suivant la revendication 6, caractérisé en ce que ledit second four a induction est mis en dépression par rapport à la pression atmosphérique. 7. Method according to claim 6, characterized in that said second induction furnace is placed under vacuum with respect to atmospheric pressure.
8. Procédé suivant l'une ou l'autre des revendications précédentes, caractérisé en ce que l'on soumet ledit acier à un traitement de métallurgie en poche.8. Method according to either of the preceding claims, characterized in that the said steel is subjected to a ladle metallurgy treatment.
9. Procédé suivant l'une ou l'autre des revendications 1 à 8, caractérisé en ce que l'on coule directement ledit acier en un lingot continu ou discontinu. 9. Method according to either of claims 1 to 8, characterized in that said steel is poured directly into a continuous or discontinuous ingot.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP97936529A EP0886682A1 (en) | 1996-10-24 | 1997-08-14 | Method for producing steel from iron sponges in an induction furnace |
| JP10518738A JP2000503348A (en) | 1996-10-24 | 1997-08-14 | Method of producing steel from iron sponge in induction furnace |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| BE9600900A BE1010710A3 (en) | 1996-10-24 | 1996-10-24 | Method of producing steel from sponge iron. |
| BE9600900 | 1996-10-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1998017830A1 true WO1998017830A1 (en) | 1998-04-30 |
Family
ID=3890055
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/BE1997/000091 WO1998017830A1 (en) | 1996-10-24 | 1997-08-14 | Method for producing steel from iron sponges in an induction furnace |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0886682A1 (en) |
| JP (1) | JP2000503348A (en) |
| BE (1) | BE1010710A3 (en) |
| WO (1) | WO1998017830A1 (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2024490A1 (en) * | 1968-11-29 | 1970-08-28 | Huettenwerk Oberhausen Ag | |
| SU436095A1 (en) * | 1973-01-12 | 1974-07-15 | О. Г. Массов, В. А. Литвак , Г. И. Нечитайлов | METHOD OF MELTING STEEL |
| FR2219232A1 (en) * | 1973-02-23 | 1974-09-20 | Asea Ab | |
| DE2418434A1 (en) * | 1974-04-17 | 1975-10-30 | Thyssen Purofer Gmbh | Continuous prodn of steel from iron sponge - in an induction furnace under a liq slag of constant basicity |
| FR2297916A1 (en) * | 1975-01-20 | 1976-08-13 | Siderurgie Fse Inst Rech | Induction furnace for metal melting - using thinner refractory around lower part which is heated by induction |
| US4099960A (en) * | 1975-02-19 | 1978-07-11 | Demag A.G. | Method of smelting metallic material, particularly iron sponge |
| JPS5399023A (en) * | 1977-02-10 | 1978-08-30 | Denki Kagaku Kogyo Kk | Desulfurization agent with low melting point |
-
1996
- 1996-10-24 BE BE9600900A patent/BE1010710A3/en not_active IP Right Cessation
-
1997
- 1997-08-14 WO PCT/BE1997/000091 patent/WO1998017830A1/en not_active Application Discontinuation
- 1997-08-14 EP EP97936529A patent/EP0886682A1/en not_active Withdrawn
- 1997-08-14 JP JP10518738A patent/JP2000503348A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2024490A1 (en) * | 1968-11-29 | 1970-08-28 | Huettenwerk Oberhausen Ag | |
| SU436095A1 (en) * | 1973-01-12 | 1974-07-15 | О. Г. Массов, В. А. Литвак , Г. И. Нечитайлов | METHOD OF MELTING STEEL |
| FR2219232A1 (en) * | 1973-02-23 | 1974-09-20 | Asea Ab | |
| DE2418434A1 (en) * | 1974-04-17 | 1975-10-30 | Thyssen Purofer Gmbh | Continuous prodn of steel from iron sponge - in an induction furnace under a liq slag of constant basicity |
| FR2297916A1 (en) * | 1975-01-20 | 1976-08-13 | Siderurgie Fse Inst Rech | Induction furnace for metal melting - using thinner refractory around lower part which is heated by induction |
| US4099960A (en) * | 1975-02-19 | 1978-07-11 | Demag A.G. | Method of smelting metallic material, particularly iron sponge |
| JPS5399023A (en) * | 1977-02-10 | 1978-08-30 | Denki Kagaku Kogyo Kk | Desulfurization agent with low melting point |
Non-Patent Citations (2)
| Title |
|---|
| DATABASE WPI Section Ch Week 7520, Derwent World Patents Index; Class M24, AN 75-33753W, XP002035001 * |
| DATABASE WPI Section Ch Week 7840, Derwent World Patents Index; Class M24, AN 78-71451A, XP002035000 * |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2000503348A (en) | 2000-03-21 |
| BE1010710A3 (en) | 1998-12-01 |
| EP0886682A1 (en) | 1998-12-30 |
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