EP0019086B1 - Process for producing desulfurizing agents for pig iron or steel melts - Google Patents

Process for producing desulfurizing agents for pig iron or steel melts Download PDF

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Publication number
EP0019086B1
EP0019086B1 EP80101984A EP80101984A EP0019086B1 EP 0019086 B1 EP0019086 B1 EP 0019086B1 EP 80101984 A EP80101984 A EP 80101984A EP 80101984 A EP80101984 A EP 80101984A EP 0019086 B1 EP0019086 B1 EP 0019086B1
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Prior art keywords
cao
weight
calcium oxide
mixture
content
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EP80101984A
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German (de)
French (fr)
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EP0019086A2 (en
EP0019086A3 (en
Inventor
Albert Braun
Willi Dr. Portz
Georg Dr. Strauss
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Hoechst AG
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Hoechst AG
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Priority to AT80101984T priority Critical patent/ATE2092T1/en
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Classifications

    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00Refining of pig-iron; Cast iron
    • C21C1/02Dephosphorising or desulfurising
    • C21C1/025Agents used for dephosphorising or desulfurising
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04Removing impurities by adding a treating agent
    • C21C7/064Dephosphorising; Desulfurising
    • C21C7/0645Agents used for dephosphorising or desulfurising

Definitions

  • the present invention relates to a method for producing desulfurizing agents based on calcium oxide-containing calcium carbide for pig iron and steel melts.
  • lime calcium carbide
  • lime calcium oxide
  • the finely divided lime was preferably introduced into the jet of carbide tapped from the furnace. Although the amount of lime that can be introduced into the molten carbide is limited and working with liquid carbide is dangerous, it was previously thought in specialist circles that this method could not be dispensed with because it was believed that only a mixture of CaC produced in the melt 2 and CaO are best suited for the desulfurization of metal melts.
  • This mixture is then milled with intensive mixing and with the exclusion of moisture at temperatures above 100 ° C. to grain sizes less than 10 mm, preferably less than 10 ⁇ m, and the milled product, likewise with the exclusion of moisture, is cooled.
  • a carbide / lime starting melt mixture with a CaO content of 20 to 45% by weight which was obtained in a known manner from lime and coke by thermal means.
  • a carbide / lime starting melt mixture with a CaO content of more than 45 to 80% by weight is first produced by finely dividing into a carbide melt which has a lime content of up to 45% by weight Enter lime up to a CaO content of up to 80% by weight and only then allow the whole to solidify into a block before breaking it at temperatures above 400 ° C.
  • the process according to the invention also has the further advantages, inter alia, that a certain Möller composition is not set in each case to produce the carbide melt, and that the lime is not previously adjusted to a specific grain size must be finely ground, but that it can be assumed that a carbide block whose CaC 2 : CaO weight ratio can fluctuate within a very wide range, ie can be practically arbitrary, and the lime also in coarse-grained form, for example in a grain size between 8 and 60 mm, can be used.
  • the block After the block had cooled to an average temperature of about 600 ° C, it was crushed to grain sizes smaller than 150 mm and the carbide, which was still 500 ° C, was covered with so much lime with a grain size of 8 to 60 mm that the resulting mixture contained a total CaO content of 50% by weight.
  • the mixture was then ground with the exclusion of moisture at a temperature of 100 ° C. to particle sizes between 0 and 100 ⁇ m, and the ground product was cooled to room temperature with the exclusion of moisture.
  • Carbide is thermally produced in a known manner from lime and coke, the lime / coke mixture in the entire Möller being adjusted to a weight ratio of approximately 110:40, which corresponds to a carbide with a CaO content of approximately 45% by weight.
  • CaO with a grain size of 3-8 mm is added to the tapping jet of this carbide in such an amount that an average content of approx. 80% by weight CaO results in the tapping crucible (about 1.2-1.3 t Ca0 per 1 t tapping jet).
  • the block is pre-crushed to a grain size of less than 150 mm and as much lime with a grain size of 8-60 mm is layered on the hot mixture that the average Ca0 content is 90% by weight.
  • the mixture is then ground to a grain size of less than 100 ⁇ m with exclusion of moisture at a temperature above 100 ° C., and the ground product is cooled to room temperature with the exclusion of moisture.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (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)
  • Coating With Molten Metal (AREA)

Abstract

The invention relates to the production of an agent for desulfurizing crude iron and steel melts, the desulfurizing agent being based on calcium carbide containing calcium oxide. To this end, a calcium carbide/calcium oxide/starting melt mixture with a CaO-content within the range 20 to 80 weight % is produced from lime and coke and allowed to solidify to a block. While the solidified block still has an average temperature of more than 400 DEG C., it is crushed to particulate material with a size of less than 150 mm. Next, the hot crushed material of at least 400 DEG C. is admixed with a quantity of calcium oxide necessary to have in the resulting mixture an overall content of CaO corresponding to that desired for the final product. The whole is thoroughly mixed and crushed with exclusion of moisture at temperatures higher than 100 DEG C. to particulate material with a size of less than 10 millimeters.

Description

Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung von Entschweflungsmitteln auf Basis von Calciumoxid enthaltendem Calciumcarbid für Roheisen- und Stahlschmelzen.The present invention relates to a method for producing desulfurizing agents based on calcium oxide-containing calcium carbide for pig iron and steel melts.

Es ist allgemein bekannt, Roheisen- und Stahlschmelzen mit Hilfe von Calciumoxid (nachfolgend kurz als Kalk bezeichnet) enthaltendem Calciumcarbid (nachfolgend Carbid genannt) zu entschwefeln (DE-Ps Nr. 1160457, DE-PS Nr. 2037758).It is generally known to desulfurize pig iron and steel melts with the aid of calcium carbide (hereinafter referred to as lime) containing calcium oxide (hereinafter referred to as lime) (DE-PS No. 1160457, DE-PS No. 2037758).

Bei der Herstellung solcher Entschweflungsmittel ging man in der Regel bislang so vor, dass man in schmelzflüssiges Carbid die erforderliche Menge an feinteiligem Kalk eintrug, um in der Schmelze eine homogene Mischung zu erzeugen, die man anschliessend abkühlen liess und zerkleinerte.In the manufacture of such desulfurizing agents, the usual procedure so far was to add the required amount of finely divided lime to the molten carbide in order to produce a homogeneous mixture in the melt, which was then allowed to cool and comminute.

Bevorzugt trug man dabei den feinteiligen Kalk in den Strahl des aus dem Ofen abgestochenen Carbides ein. Obwohl die in Carbidschmelze eintragbare Menge Kalk begrenzt und das Arbeiten mit flüssigem Carbid mit Gefahren verbunden ist, war man in Fachkreisen bisher der Auffassung, auf diese Methode nicht verzichten zu können, da man der Meinung war, nur eine in der Schmelze hergestellte Mischung von CaC2 und CaO sei für eine Entschweflung von Metallschmelzen am besten geeignet.The finely divided lime was preferably introduced into the jet of carbide tapped from the furnace. Although the amount of lime that can be introduced into the molten carbide is limited and working with liquid carbide is dangerous, it was previously thought in specialist circles that this method could not be dispensed with because it was believed that only a mixture of CaC produced in the melt 2 and CaO are best suited for the desulfurization of metal melts.

In die gleiche Richtung weist daher auch der ältere Vorschlag, zur Herstellung eines Entschweflungsmittels auf der Basis von Carbid mit einem CaO-Gehalt von mehr als 45 bis 80 Gew.%, gemäss der EP-A1 Nr. 0019087, in eine in üblicher Weise erzeugte Carbidschmelze, welche bereits einen CaO-Gehalt bis zu 45 Gew.% aufweist, feinteiliges CaO in einem Überschuss von 3 bis 15 Gew.%, bezogen auf die im Endprodukt gewünschte Menge, einzutragen. Dann muss die erhaltene Mischung unter Erstarren auf Temperaturen von 350 bis 450° C abgekühlt und bei diesen Temperaturen auf Korngrössen kleiner als 150 mm vorgebrochen werden. Der dabei zwangsläufig anfallende Kornanteil kleiner als 4 mm wird dann vom verbleibenden Produkt abgetrennt und letzteres unter Feuchtigkeitsausschluss durch Brechen und Mahlen auf Korngrössen kleiner als 10 mm zerkleinert. Eine solche Arbeitsweise führt durch die Zugabe eines Überschusses an CaO in die Carbidschmelze und Absieben des Feinkornanteils unter 4 mm zu nicht immer exakt reproduzierbaren CaO-Gehalten in den Endprodukten.The older proposal, therefore, for producing a desulfurization agent based on carbide with a CaO content of more than 45 to 80% by weight, according to EP-A1 No. 0019087, in a conventional manner also points in the same direction Carbide melt, which already has a CaO content of up to 45% by weight, of finely divided CaO in an excess of 3 to 15% by weight, based on the amount desired in the end product. The mixture obtained then has to be solidified to temperatures of 350 to 450 ° C. and has to be pre-broken at these temperatures to grain sizes smaller than 150 mm. The inevitably occurring grain fraction smaller than 4 mm is then separated from the remaining product and the latter is crushed to a grain size smaller than 10 mm with exclusion of moisture by breaking and grinding. Such a procedure leads to the addition of an excess of CaO into the carbide melt and sieving of the fine grain fraction below 4 mm to CaO contents in the end products which are not always exactly reproducible.

Überraschenderweise wurde nun gefunden, dass man die Nachteile der bekannten Arbeitsweisen vermeiden und ein hochwirksames Entschweflungsmittel für Roheisen- und Stahlschmelzen erhalten kann, wenn man zunächst auf thermischem Wege aus Kalk und Koks ein Carbid/ Kalk-Ausgangsschmelzgemisch mit einem beliebigen CaO-Gehalt von 20 bis 80% erzeugt, welches man durch Abkühlenlassen zu einem Block erstarren lässt. Während der erstarrte Block noch eine Durchschnittstemperatur von mehr als 400° C, vorzugsweise zwischen 400° C und der Erstarrungstemperatur der Schmelze, aufweist, bricht man ihn dann auf Korngrössen kleiner als 150 mm vor und gibt auf das zerkleinerte und noch mindestens 400° C heisse Gemisch Kalk in einer solchen Menge auf, dass der sich in der entstehenden Mischung ergebende Gesamtgehalt an CaO dem im Endprodukt gewünschten CaO-Gehalt entspricht. Vorzugsweise gibt man so viel Kalk auf, dass sich in der Mischung ein Gesamtgehalt an CaO von über 45 bis 90 Gew.% ergibt. Anschliessend wird dann diese Mischung unter intensiver Vermengung und unter Feuchtigkeitsausschluss bei Temperaturen oberhalb 100° C auf Korngrössen kleiner als 10 mm, vorzugsweise kleiner als 10 µm, gemahlen, und das gemahlene Produkt, ebenfalls unter Feuchtigkeits ausschluss, abgekühlt.Surprisingly, it has now been found that the disadvantages of the known working methods can be avoided and a highly effective desulfurizing agent for pig iron and steel melts can be obtained if a carbide / lime starting melt mixture with any CaO content of 20 to is first obtained thermally from lime and coke 80% generated, which is allowed to solidify into a block by allowing it to cool. While the solidified block still has an average temperature of more than 400 ° C, preferably between 400 ° C and the solidification temperature of the melt, it is then broken down to grain sizes smaller than 150 mm and put on the crushed and still at least 400 ° C hot Mix lime in such an amount that the total CaO content in the resulting mixture corresponds to the CaO content desired in the end product. It is preferable to add enough lime to give a total CaO content of over 45 to 90% by weight in the mixture. This mixture is then milled with intensive mixing and with the exclusion of moisture at temperatures above 100 ° C. to grain sizes less than 10 mm, preferably less than 10 μm, and the milled product, likewise with the exclusion of moisture, is cooled.

Vorzugsweise setzt man ein Carbid/Kalk-Ausgangsschmelzgemisch mit einem CaO-Gehalt von 20 bis 45 Gew.% ein, das in bekannter Weise auf thermischem Wege aus Kalk und Koks gewonnen wurde. Man kann aber auch so verfahren, dass man zunächst ein Carbid/Kalk-Ausgangsschmelzgemisch mit einem CaO-Gehalt von über 45 bis 80 Gew.% herstellt, indem man in eine vorliegende Carbidschmelze, die einen Kalkgehalt bis zu 45 Gew.% aufweist, feinteiligen Kalk bis zu einem CaO-Gehalt von maximal bis zu 80 Gew.% einträgt und erst dann das Ganze zu einem Block erstarren lässt, bevor man diesen bei Temperaturen oberhalb 400° C vorbricht.It is preferable to use a carbide / lime starting melt mixture with a CaO content of 20 to 45% by weight, which was obtained in a known manner from lime and coke by thermal means. However, one can also proceed in such a way that a carbide / lime starting melt mixture with a CaO content of more than 45 to 80% by weight is first produced by finely dividing into a carbide melt which has a lime content of up to 45% by weight Enter lime up to a CaO content of up to 80% by weight and only then allow the whole to solidify into a block before breaking it at temperatures above 400 ° C.

Ausser dass das Vermischen des Kalkes mit einer Carbidschmelze und den damit verbundenen Schwierigkeiten vermieden werden kann, besitzt das erfindungsgemässe Verfahren u.a. auch die weiteren Vorteile, dass zur Erzeugung der Carbidschmelze nicht jeweils eine bestimmte Möllerzusammensetzung eingestellt, und dass der Kalk vorher nicht auf eine bestimmte Korngrösse feingemahlen werden muss, sondern dass von einem Carbidblock ausgegangen werden kann, dessen CaC2:CaO-Gewichtsverhä)tnis innerhalb eines sehr weiten Bereiches schwanken, d.h. praktisch beliebig sein kann, und der Kalk auch in grobkörniger Form, beispielsweise in einer Korngrösse zwischen 8 und 60 mm, eingesetzt werden kann.In addition to the fact that mixing the lime with a carbide melt and the difficulties associated with it can be avoided, the process according to the invention also has the further advantages, inter alia, that a certain Möller composition is not set in each case to produce the carbide melt, and that the lime is not previously adjusted to a specific grain size must be finely ground, but that it can be assumed that a carbide block whose CaC 2 : CaO weight ratio can fluctuate within a very wide range, ie can be practically arbitrary, and the lime also in coarse-grained form, for example in a grain size between 8 and 60 mm, can be used.

Beispiel 1:Example 1:

Aus einer für die Herstellung von technischem Carbid üblichen Schmelze mit einem CaC2 -Gehalt von 80 Gew.% und CaO-Gehalt von 20 Gew.% wurde in einem Tiegel durch Abkühlenlassen dieser Schmelze in bekannter Weise ein Carbidblock entsprechender Zusammensetzung erzeugt.From a melt customary for the production of technical carbide with a CaC 2 content of 80% by weight and a CaO content of 20% by weight, a carbide block of the appropriate composition was produced in a crucible in a known manner by allowing this melt to cool.

Nachdem sich der Block auf eine Durchschnittstemperatur von etwa 600° C abgekühlt hatte, wurde er auf Korngrössen kleiner als 150 mm vorgebrochen und das noch 500° C heisse Carbid mit so viel Kalk einer Korngrösse von 8 bis 60 mm überschichtet, dass die sich ergebende Mischung einen CaO-Gehalt von insgesamt 50 Gew.% enthielt.After the block had cooled to an average temperature of about 600 ° C, it was crushed to grain sizes smaller than 150 mm and the carbide, which was still 500 ° C, was covered with so much lime with a grain size of 8 to 60 mm that the resulting mixture contained a total CaO content of 50% by weight.

Anschliessend wurde die Mischung unter Feuchtigkeitsausschluss bei einer Temperatur von 100° C auf Korngrössen zwischen 0 und 100 µm gemahlen, und das gemahlene Produkt unter Feuchtigkeitsausschluss auf Raumtemperatur abgekühlt.The mixture was then ground with the exclusion of moisture at a temperature of 100 ° C. to particle sizes between 0 and 100 μm, and the ground product was cooled to room temperature with the exclusion of moisture.

Mit 1500 kg von diesem Produkt wurden 300000 kg einer Roheisenschmelze, die 0,03 Gew.% Schwefel enthielt, in bekannter Weise entschwefelt. Der S-Gehalt des behandelten Eisens betrug weniger als 0,005 Gew.%.With 1500 kg of this product, 300000 kg of a pig iron melt containing 0.03% by weight of sulfur were desulfurized in a known manner. The S content of the treated iron was less than 0.005% by weight.

Beispiel 2:Example 2:

In bekannter Weise wird aus Kalk und Koks Carbid thermisch hergestellt, wobei die Kalk/Koks-Mischung im gesamten Möller auf ein Gewichtsverhältnis von etwa 110:40 eingestellt wird, was einem Carbid mit einem CaO-Gehalt von etwa 45 Gew.% entspricht.Carbide is thermally produced in a known manner from lime and coke, the lime / coke mixture in the entire Möller being adjusted to a weight ratio of approximately 110:40, which corresponds to a carbide with a CaO content of approximately 45% by weight.

Dem Abstichstrahl dieses Carbides wird CaO der Körnung 3-8 mm in einer solchen Menge zudosiert, dass sich im Abstichtiegel ein Durchschnittsgehalt von ca. 80 Gew.% CaO ergibt (auf 1 t Abstichstrahl etwa 1,2-1,3 t Ca0).CaO with a grain size of 3-8 mm is added to the tapping jet of this carbide in such an amount that an average content of approx. 80% by weight CaO results in the tapping crucible (about 1.2-1.3 t Ca0 per 1 t tapping jet).

Nach dem Abkühlen des Tiegels auf eine Durchschnittstemperatur von nicht unter 600° C, was bereits nach 4 h der Fall ist, wird der Block auf eine Korngrösse kleiner als 150 mm vorgebrochen und auf das heisse Gemisch so viel Kalk der Körnung 8-60 mm geschichtet, dass der Durchschnitts-Ca0-Gehalt 90 Gew.% beträgt. Anschliessend wird unter Feuchtigkeitsausschluss bei einer Temperatur oberhalb 100° C auf eine Korngrösse kleiner als 100 µm gemahlen, und das gemahlene Produkt unter Feuchtigkeitsausschluss auf Zimmertemperatur abgekühlt.After the crucible has cooled to an average temperature of not less than 600 ° C, which is already the case after 4 hours, the block is pre-crushed to a grain size of less than 150 mm and as much lime with a grain size of 8-60 mm is layered on the hot mixture that the average Ca0 content is 90% by weight. The mixture is then ground to a grain size of less than 100 μm with exclusion of moisture at a temperature above 100 ° C., and the ground product is cooled to room temperature with the exclusion of moisture.

Mit diesem Gemisch werden, bezogen auf den Carbidgehalt, die gleichen Entschwefelungsergebnisse erzielt, wie im Beispiel 1 geschildert.With this mixture, based on the carbide content, the same desulfurization results are achieved as described in Example 1.

Claims (6)

1. Process for making an agent for desulfurizing crude iron and steel melts, the desulfurizing agent being based on calcium carbide containing calcium oxide, which comprises: initially producing, from lime and coke, a calcium carbide/calcium oxide melt mixture with a CaO-content within the range 20 to 80 weight%; allowing the starting melt mixture to solidify to a block; precrushing the solidified block while it still has an average temperature of more than 400° C to lumpy material with a size of less than 150 mm; admixing the hot crushed material of at least 400° C with a quantity of calcium oxide necessary to have in the resulting mixture an overall content of CaO corresponding to the CaO-content desired for the final product; thoroughly mixing and crushing the whole with exclusion of moisture at temperatures higher than 100° C to particulate material with a size of less than 10 mm; and cooling the ground product, equally with exclusion of moisture.
2. Process as claimed in claim 1, wherein the precrushed mixture is covered with coarse particulate CaO with a size of 8 to 60 mm.
3. Process as claimed in claim 1 or 2, wherein the precrushed mixture is covered with a quantity of CaO necessary for the resulting mixture to contain 45 to 90 weight% of CaO.
4. Process as claimed in any of claims 1 to 3, wherein the precrushing step is effected at temperatures between 400° C and the solidification temperature.
5. Process as claimed in any of claims 1 to 4, wherein the calcium carbide/calcium oxide starting melt mixture containing 20 to 45 weight% of CaO is produced thermally in customary manner from lime and coke.
6. Process as claimed in any of claims 1 to 4, wherein the calcium carbide/calcium oxide starting melt mixture containing more than 45 up to 80 weight% of CaO is produced by admixing an existing calcium carbide melt having up to 45 weight% of calcium oxide therein with fine particulate calcium oxide so as to establish a CaO-content of at most 80 weight%, and thereafter allowing the whole to solidify to a block.
EP80101984A 1979-05-19 1980-04-14 Process for producing desulfurizing agents for pig iron or steel melts Expired EP0019086B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT80101984T ATE2092T1 (en) 1979-05-19 1980-04-14 PROCESS FOR THE MANUFACTURE OF DESULPHURIZING AGENTS FOR MELTED PIG IRON OR STEEL.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19792920353 DE2920353A1 (en) 1979-05-19 1979-05-19 METHOD FOR THE PRODUCTION OF DEHANIZING AGENTS FOR CRUDE IRON OR STEEL MELT
DE2920353 1979-05-19

Publications (3)

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EP0019086A2 EP0019086A2 (en) 1980-11-26
EP0019086A3 EP0019086A3 (en) 1981-04-01
EP0019086B1 true EP0019086B1 (en) 1982-12-22

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ID=6071196

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EP80101984A Expired EP0019086B1 (en) 1979-05-19 1980-04-14 Process for producing desulfurizing agents for pig iron or steel melts

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US (1) US4318822A (en)
EP (1) EP0019086B1 (en)
JP (1) JPS55154519A (en)
AT (1) ATE2092T1 (en)
CA (1) CA1141965A (en)
DE (2) DE2920353A1 (en)
ES (1) ES8101120A1 (en)
NO (1) NO151971C (en)
ZA (1) ZA802943B (en)

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CN107344188A (en) * 2017-07-28 2017-11-14 靖西天桂铝业有限公司 Bauxite washing tail mud dry treatment and comprehensive utilization new technology

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DE2952686A1 (en) * 1979-12-29 1981-07-02 Hoechst Ag, 6230 Frankfurt METHOD FOR THE PRODUCTION OF DESULFURING AGENTS FOR BOD IRON OR STEEL MELT
DE3111510A1 (en) * 1981-03-24 1982-10-07 Hoechst Ag, 6000 Frankfurt DESULFURATION MIXTURE AND METHOD FOR THE PRODUCTION THEREOF
DE3111509A1 (en) * 1981-03-24 1982-10-07 Hoechst Ag, 6000 Frankfurt METHOD FOR THE PRODUCTION OF DESULFURING AGENTS FOR BOD IRON OR STEEL MELT
DE3535280A1 (en) * 1985-10-03 1987-04-09 Hoechst Ag DESULFURATION MIXTURE FOR METAL MELTS, A METHOD FOR THE PRODUCTION THEREOF AND ITS USE
US5002733A (en) * 1989-07-26 1991-03-26 American Alloys, Inc. Silicon alloys containing calcium and method of making same
US5397379A (en) * 1993-09-22 1995-03-14 Oglebay Norton Company Process and additive for the ladle refining of steel
US6179895B1 (en) 1996-12-11 2001-01-30 Performix Technologies, Ltd. Basic tundish flux composition for steelmaking processes

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AT264560B (en) * 1966-08-25 1968-09-10 Gustav Dipl Ing Wolfram Basic steelmaking process
DE1919414B2 (en) * 1969-04-17 1977-07-14 Hoechst Ag, 6000 Frankfurt METHOD AND DEVICE FOR COOLING CALCIUM CARBIDE PICKED IN VESSELS
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DE2037758C3 (en) * 1970-07-30 1979-08-02 Hoechst Ag, 6000 Frankfurt Process for the production of calcium carbide for the desulfurization of metal melts
DE2326539C3 (en) * 1973-05-24 1975-11-13 Sueddeutsche Kalkstickstoff-Werke Ag, 8223 Trostberg Process for the production of a desulphurisation mixture for iron melts from calcium carbide and at least one water-containing substance
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107344188A (en) * 2017-07-28 2017-11-14 靖西天桂铝业有限公司 Bauxite washing tail mud dry treatment and comprehensive utilization new technology

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Publication number Publication date
ATE2092T1 (en) 1983-01-15
NO151971C (en) 1985-07-10
DE3061404D1 (en) 1983-01-27
ES491355A0 (en) 1980-12-16
EP0019086A2 (en) 1980-11-26
EP0019086A3 (en) 1981-04-01
JPS6353245B2 (en) 1988-10-21
JPS55154519A (en) 1980-12-02
US4318822A (en) 1982-03-09
CA1141965A (en) 1983-03-01
NO151971B (en) 1985-04-01
DE2920353A1 (en) 1980-11-27
ES8101120A1 (en) 1980-12-16
ZA802943B (en) 1981-06-24
NO801468L (en) 1980-11-20

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