EP0019087A1 - Desulphurising agents for pig iron and steel melts, and process for their manufacture - Google Patents
Desulphurising agents for pig iron and steel melts, and process for their manufacture Download PDFInfo
- Publication number
- EP0019087A1 EP0019087A1 EP80101985A EP80101985A EP0019087A1 EP 0019087 A1 EP0019087 A1 EP 0019087A1 EP 80101985 A EP80101985 A EP 80101985A EP 80101985 A EP80101985 A EP 80101985A EP 0019087 A1 EP0019087 A1 EP 0019087A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- weight
- calcium oxide
- calcium
- calcium carbide
- temperatures
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 9
- 239000000161 steel melt Substances 0.000 title claims abstract description 7
- 238000000034 method Methods 0.000 title claims description 12
- 229910000805 Pig iron Inorganic materials 0.000 title claims description 7
- 238000004519 manufacturing process Methods 0.000 title claims description 3
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims abstract description 37
- 239000000292 calcium oxide Substances 0.000 claims abstract description 36
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims abstract description 21
- 239000005997 Calcium carbide Substances 0.000 claims abstract description 16
- CLZWAWBPWVRRGI-UHFFFAOYSA-N tert-butyl 2-[2-[2-[2-[bis[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]amino]-5-bromophenoxy]ethoxy]-4-methyl-n-[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]anilino]acetate Chemical compound CC1=CC=C(N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)C(OCCOC=2C(=CC=C(Br)C=2)N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)=C1 CLZWAWBPWVRRGI-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000000203 mixture Substances 0.000 claims abstract description 9
- 230000003009 desulfurizing effect Effects 0.000 claims abstract description 8
- 230000007717 exclusion Effects 0.000 claims abstract 3
- 239000000047 product Substances 0.000 claims description 12
- 239000007795 chemical reaction product Substances 0.000 claims description 7
- 239000000155 melt Substances 0.000 claims description 6
- 229910052799 carbon Inorganic materials 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 claims description 2
- 238000007711 solidification Methods 0.000 claims 1
- 230000008023 solidification Effects 0.000 claims 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 4
- 229910052742 iron Inorganic materials 0.000 abstract description 2
- 239000000463 material Substances 0.000 abstract 3
- 239000012467 final product Substances 0.000 abstract 1
- 239000002245 particle Substances 0.000 abstract 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 4
- 238000006477 desulfuration reaction Methods 0.000 description 4
- 230000023556 desulfurization Effects 0.000 description 4
- 239000010436 fluorite Substances 0.000 description 4
- 229910052717 sulfur Inorganic materials 0.000 description 4
- 239000011593 sulfur Substances 0.000 description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 3
- 235000011941 Tilia x europaea Nutrition 0.000 description 3
- 239000000654 additive Substances 0.000 description 3
- 239000004571 lime Substances 0.000 description 3
- 239000011575 calcium Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000256 polyoxyethylene sorbitan monolaurate Substances 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
- C21C7/0645—Agents used for dephosphorising or desulfurising
-
- 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
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
- C21C1/025—Agents used for dephosphorising or desulfurising
Definitions
- the present invention relates to desulfurizing agents for pig iron and steel melts based on a calcium carbide containing calcium oxide and to processes for their production.
- carbide for desulfurizing metal melts, in particular those carbide which, in addition to calcium oxide (hereinafter referred to briefly as lime), also contains fluorspar.
- additives in the form of a mixture consisting of lime and fluorspar are added to the melt of a relatively high-percentage carbide, the grain size of the additives being less than 20 mm, preferably 0.5 to 10 mm, and their adhesion and Crystal water content should be less than 5% by weight, preferably less than 0.5% by weight.
- carbide which has 20 to 55% by weight CaC 2 and a high CaO content of more than 45 to 80% by weight, is better suited for the desulfurization of pig iron and steel melts, especially when it is in has been produced in a certain way, and that the relatively expensive fluorspar as an additive can also be dispensed with.
- the desulfurizing agent according to the invention is obtained by entering finely divided calcium oxide in an existing and customarily produced calcium carbide melt, which already has a calcium oxide content of up to 45% by weight, in an excess of 3 to 15% by weight, based on that in the end product desired amount.
- the mixture obtained is then solidified to temperatures of 350 to 450 ° C. and pre-crushed to grain size smaller than 150 mm at these temperatures.
- the inevitably occurring grain fraction smaller than 4 mm is then separated from the remaining product and the latter is crushed to exclude moisture by breaking and grinding to grain sizes smaller than 10 mm.
- the calcium oxide which is introduced into the melt, is preheated to temperatures up to 2000 ° C., preferably up to 1100 ° C., and introduced hot into the melt at these temperatures, it is possible to determine the CaO content in the carbide to increase to 80% by weight, the higher the preheating chosen, the higher the desired proportion of additionally dissolved calcium oxide should be between 45 and 80% by weight. This enables use in low-carbon pig iron and steel melts and also increases the desulfurization yield based on calcium carbide.
- a calcium carbide melt is preferably used, which contains between 20 and 45% by weight of CaO.
- the portions smaller than 4 mm which have been screened off after the preliminary crushing essentially consist of CaaO and can be returned to the process as finely divided calcium oxide, where they, together with fresh CaO, serve as the starting product.
- the lime-coke mixture in the Möller is adjusted to a weight ratio of 100:40, which corresponds to a carbide with a CaO content of approx. 40% by weight.
- CaO with a grain size of 3 to 8 mm and a Ca (OR) 2 and CaCO 3 content of less than 1% by weight each is injected into the jet of the molten carbide which has been tapped from the furnace into a crucible at such a rate and in such a rate Amounts entered that, until the crucible is filled, there is a total CaC 2: CaO weight ratio of 43:57, which corresponds to an excess of 14% by weight CaO, based on the CaO content of 50% by weight desired in the end product. It is then cooled until the average temperature of the solidified carbide block is approximately 400 ° C. and the block has broken down to sizes smaller than 150 mm.
- the fractions less than 4 mm obtained during the preliminary crushing essentially contain the CaO used in excess, while the remaining product with grain sizes larger than 4 mm represents an intensive mixture of 50% by weight CaC 2 and 50% by weight CaO, which is then applied in the usual way Grain sizes smaller than 10 mm are ground.
- the screened grain fraction smaller than 4 mm is used together with fresh lime as a starting product.
- Example 2 The procedure is as in Example 1, with the changes that the CaO is preheated to a temperature of about 1100 ° C. and the amount of CaO is increased so that a total Cau content of 62.5 Gev % results, which corresponds to an excess of 4% by weight, based on the desired content of 60% by weight of CaO in the finished end product.
- 1800 kg of the product worked up and ground according to the invention are used to desulfurize 300,000 kg of a molten steel having a sulfur content of 0.02% by weight at 1650 ° C.
- the sulfur content of the melt is reduced to less than 0.005% by weight.
Landscapes
- 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)
- Heat Treatment Of Steel (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Abstract
Description
Gegenstand der vorliegenden Erfindung sind Entschweflungsmittel für Roheisen- und Stahlschmelzen auf der Basis eines Calciumoxid enthaltenden Calciumcarbids sowie Verfahren zu deren Herstellung.The present invention relates to desulfurizing agents for pig iron and steel melts based on a calcium carbide containing calcium oxide and to processes for their production.
Es ist bereits bekannt, zur Entschweflung von Metallschmelzen Calciumcarbid (nachfolgend kurz als Carbid bezeichnet) einzusetzen, insbesondere solches Carbid,das neben Calciumoxid (nachfolgend kurz als Kalk bezeichnet) noch Flußspat enthält.It is already known to use calcium carbide (hereinafter referred to briefly as carbide) for desulfurizing metal melts, in particular those carbide which, in addition to calcium oxide (hereinafter referred to briefly as lime), also contains fluorspar.
Die Herstellung eines solchen Entschweflungsmittels ist in der DE-PS 20 37 758 beschrieben.The preparation of such a desulfurizing agent is described in DE-PS 20 37 758.
Gemäß diesem bekannten Verfahren werden der Schmelze eines relativ hochprozentigen Carbides Zuschlagstoffe in Form eines aus Kalk und Flußspat bestehenden Gemisches zugesetzt, wobei die Körnung der Zuschlagstoffe weniger als 20 mm, vorzugsweise 0,5 bis 10 mm, und deren Haft- und Kristallwassergehalt weniger als 5 Gew%, vorzugsweise weniger als 0,5 Gew%, betragen soll.According to this known method, additives in the form of a mixture consisting of lime and fluorspar are added to the melt of a relatively high-percentage carbide, the grain size of the additives being less than 20 mm, preferably 0.5 to 10 mm, and their adhesion and Crystal water content should be less than 5% by weight, preferably less than 0.5% by weight.
Auf diese Weise gelingt es Carbid herzustellen, das mehr als 45 bis 65 % CaC2, aber nur etwa 25 bis 26,5%Ca0 enthält. Die Praxis hat jedoch gezeigt, daß Flußspat in derartigen Mischungen die Auskleidung aller Entschwefelungsgefäße stark angreift. Daher haben diese Mischungen anwendungstechnisch keine Bedeutung erlangt.In this way it is possible to produce carbide which contains more than 45 to 65% CaC 2 , but only about 25 to 26.5% Ca0. Practice has shown, however, that fluorspar in such mixtures strongly attacks the lining of all desulfurization vessels. Therefore, these mixtures have no significance in terms of application technology.
Überraschenderweise hat sich jedoch gezeigt, daß sich Carbid, welches 20 bis 55 Gew% CaC2 und einen hohen CaO-Gehalt von mehr als 45 bis 80 Gew% aufweist, besser zur Entschweflung von Roheisen- und Stahlschmelzen eignet, insbesondere dann, wenn es in einer bestimmten Weise hergestellt worden ist, und daß außerdem auf den relativ teuren Flußspat als Zuschlagstoff verzichtet werden kann.Surprisingly, however, it has been shown that carbide, which has 20 to 55% by weight CaC 2 and a high CaO content of more than 45 to 80% by weight, is better suited for the desulfurization of pig iron and steel melts, especially when it is in has been produced in a certain way, and that the relatively expensive fluorspar as an additive can also be dispensed with.
Das erfindungsgemäße Entschweflungsmittel erhält man dadurch, daß man in eine vorliegende und in üblicher Weise erzeugte Calciumcarbidschmelze, welche bereits einen Calciumoxidgehalt bis zu 45 Gew% aufweist, feinteiliges Calciumoxid-einträgt, in einem Überschuß von 3 bis 15 Gew%, bezogen auf die im Endprodukt gewünschte Menge. Dann wird die erhaltene Mischung unter Erstarren auf Temperaturen von 350 bis 450°C abgekühlt und bei diesen Temperaturen auf Korngrößaikleiner als 150 mm vorgebrochen. Den dabei zwangsläufig anfallenden Kornanteil kleiner als 4 mm trennt man anschließend vom verbleibenden Produkt ab und zerkleinert letzteres unter Feuchtigkeitsausschluß durch Brechen und Mahlen auf Korngrößen kleiner als 10 mm.The desulfurizing agent according to the invention is obtained by entering finely divided calcium oxide in an existing and customarily produced calcium carbide melt, which already has a calcium oxide content of up to 45% by weight, in an excess of 3 to 15% by weight, based on that in the end product desired amount. The mixture obtained is then solidified to temperatures of 350 to 450 ° C. and pre-crushed to grain size smaller than 150 mm at these temperatures. The inevitably occurring grain fraction smaller than 4 mm is then separated from the remaining product and the latter is crushed to exclude moisture by breaking and grinding to grain sizes smaller than 10 mm.
Zwreckmäßigerweise führt man diese sogenannte "Magerung" des Carbides unter Ausnutzung dessen Wärmeinhaltes in einem Tiegel durch.Unfortunately, this so-called "leaning" of the carbide is carried out in a crucible using its heat content.
Wenn das Calciumoxid, welches in die Schmelze eingetragen wird, vorher auf Temperaturen bis zu 2000°C, vorzugsweise bis zu 1100°C, vorerhitzt und mit diesen Temperaturen heiß in die Schmelze eingebracht wird, so ist es möglich, den CaO-Gehalt im Carbid bis auf 80 Gew% zu erhöhen, wobei die Vorerhitzung um so höher gewählt wird, je höher der gewünschte Anteil an zusätzlich gelöstem Calciumoxid zwischen 45- und 80 Gew% liegen soll. Dadurch wird die Anwendung in kohlenstoffarmen Roheisen- und Stahlschmelzen ermöglicht und außerdem die Entschwefelungsausbeute bezogen auf Calciumcarbid erhöht.If the calcium oxide, which is introduced into the melt, is preheated to temperatures up to 2000 ° C., preferably up to 1100 ° C., and introduced hot into the melt at these temperatures, it is possible to determine the CaO content in the carbide to increase to 80% by weight, the higher the preheating chosen, the higher the desired proportion of additionally dissolved calcium oxide should be between 45 and 80% by weight. This enables use in low-carbon pig iron and steel melts and also increases the desulfurization yield based on calcium carbide.
Vorzugsweise wird von einer Calciumcarbidachmelze ausgegangen, welche zwischen 20 und 45 Gew% CaO enthält.A calcium carbide melt is preferably used, which contains between 20 and 45% by weight of CaO.
Die nach dem Vorbrechen abgesiebten Anteile kleiner als 4 mm bestehen im wesentlichen aus CaaO und können als feinteiliges Calciumoxid wieder in den Prozeß zurückgeführt werden, wo sie, zusammen mit frischen CaO, als Ausgangsprodukt dienen.The portions smaller than 4 mm which have been screened off after the preliminary crushing essentially consist of CaaO and can be returned to the process as finely divided calcium oxide, where they, together with fresh CaO, serve as the starting product.
Es empfiehlt sich, das Calciumoxid mit einer Korngröße von 1 bis 8 mm einzusetzen und darauf zu achten, daß es Gehalte von jeweils weniger als 1 Gew% an Ca(OH)2 und CaCO3 aufweist.It is advisable to use calcium oxide with a grain size of 1 to 8 mm and to ensure that it contains less than 1% by weight of Ca (OH) 2 and CaCO 3 .
Nicht vorhersehbar war für den Fachmann, daß durch das Absieben der nach dem Vorbrechen anfallenden Anteile kleiner als 4 mm aus dem Produkt die Anteile entfernt werden, welche keine oder nur eine geringe Entschweflungswirkung besitzen und so die Wirksamkeit des Endproduktes erheblich gesteigert wird. Überraschend war ferner, daß sich das erfindungsgemäß hergestellte Produkt auch wesentlich besser mahlen läßt als nach bekannten Verfahren erhaltene Produkte. Dies ist deshalb von besonderer Wichtigkeit, weil das Produkt in zahlreichen Fällen mit einer Körnung kleiner als 100 µm eingesetzt werden muß.It was not foreseeable for the person skilled in the art that by sieving off the portions of less than 4 mm after the preliminary breaking, the portions which have no or only a slight desulfurization effect are removed from the product and the effectiveness of the end product is considerably increased. It was also surprising that the product produced according to the invention can also be ground much better than products obtained by known processes. This is of particular importance because in many cases the product has to be used with a grain size of less than 100 µm.
In bekannter Weise wird aus Kalk und Koks Calciumcarbid, z.B. elektrcthermisch,hergestellt, wobei die Kalk-Koks-Mischung im Möller auf ein Gewichtsverhältnis von 100 : 40 eingestellt wird, was einem Carbid mit einem CaO-Gehalt von ca. 40 Gew% entspricht.Calcium carbide, e.g. Electrically produced, the lime-coke mixture in the Möller is adjusted to a weight ratio of 100:40, which corresponds to a carbide with a CaO content of approx. 40% by weight.
In den Strahl des aus dem Ofen in einen Tiegel abgestochenen schmelzflüssigen Carbides wird CaO mit einer Körnung von 3 bis 8 mm und einem Ca(OR)2- und CaCO3-Gehalt von jeweils weniger als 1 Gew% mit einer solchen Geschwindigkeit und in solchen Mengen eingetragen, daß, bis der Tiegel gefüllt ist, insgesamt ein CaC2 : CaO Gewichtsverhältnis von 43 : 57 vorliegt, was einem Überschuß von 14 Gew% CaO, bezogen auf den im Endprodukt gewünschten CaO-Gehalt von 50 Gew% entspricht. Dann wird abgekühlt, bis die Durchschnittstemperatur des dabei erstarrten Carbidblockes etwa 400°C beträgt und der Block auf Größen kleiner als 150 mm vorgebrochen ist.CaO with a grain size of 3 to 8 mm and a Ca (OR) 2 and CaCO 3 content of less than 1% by weight each is injected into the jet of the molten carbide which has been tapped from the furnace into a crucible at such a rate and in such a rate Amounts entered that, until the crucible is filled, there is a total CaC 2: CaO weight ratio of 43:57, which corresponds to an excess of 14% by weight CaO, based on the CaO content of 50% by weight desired in the end product. It is then cooled until the average temperature of the solidified carbide block is approximately 400 ° C. and the block has broken down to sizes smaller than 150 mm.
Die beim Vorbrechen anfallenden Anteile kleiner als 4 mm enthalten im wesentlichen das im Überschuß eingesetzte CaO, während das zurückbleibende Produkt mit Korngrößen größer als 4 mm ein intensives Gemisch von 50 Gew% CaC2 und 50 Gew% CaO darstellt, das anschließend in üblicher Weise auf Korngrößen kleiner als 10 mm gemahlen wird. Die abgesiebte Kornfraktion kleiner als 4 mm wird zusammen mit frischem Kalk wieder als Ausgangsprodukt eingesetzt.The fractions less than 4 mm obtained during the preliminary crushing essentially contain the CaO used in excess, while the remaining product with grain sizes larger than 4 mm represents an intensive mixture of 50% by weight CaC 2 and 50% by weight CaO, which is then applied in the usual way Grain sizes smaller than 10 mm are ground. The screened grain fraction smaller than 4 mm is used together with fresh lime as a starting product.
Durch Einblasen von 1500 kg des erfindungsgemäß erhaltenen Produktes in 300 000 kg einer Roheisenschmelze mit einem Schwefelgehalt von 0,03 Gew% bei Temperaturen von 1400°C wird der Schwefelgehalt der Eisenschmelze auf weniger als 0,005 Gew% gesenkt.By blowing 1500 kg of the product obtained according to the invention into 300,000 kg of pig iron melt with a sulfur content of 0.03% by weight at temperatures of 1400 ° C., the sulfur content of the iron melt is reduced to less than 0.005% by weight.
Es wird wie im Beispiel 1 verfahren, mit den Änderungen, daß das CaO vor dem Eintragen auf eine Temperatur von etwa 1100°C vorerhitzt und die Menge an CaO so erhöht wird, daß sich insgesamt im Tiegel ein Cau-Gehalt von 62,5 Gev% ergibt, was einem Überschuß von 4 Gew% entspricht, bezogen auf den im fertigen Endprodukt gewünschten Gehalt von 60 Gew% CaO.The procedure is as in Example 1, with the changes that the CaO is preheated to a temperature of about 1100 ° C. and the amount of CaO is increased so that a total Cau content of 62.5 Gev % results, which corresponds to an excess of 4% by weight, based on the desired content of 60% by weight of CaO in the finished end product.
1800 kg des erfindungsgemäß aufgearbeiteten und gemahlenen Produktes werden zur Entschweflung von 300 000 kg einer Stahlschmelze mit einem Schwefelgehalt von 0,02 Gew% bei 1650°C eingesetzt. Dabei wird der Schwefelgehalt der Schmelze auf weniger als 0,005 Gew% gesenkt.1800 kg of the product worked up and ground according to the invention are used to desulfurize 300,000 kg of a molten steel having a sulfur content of 0.02% by weight at 1650 ° C. The sulfur content of the melt is reduced to less than 0.005% by weight.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT80101985T ATE4227T1 (en) | 1979-05-14 | 1980-04-14 | DESULPHURIZING AGENT FOR PIG IRON AND STEEL MELT AND A PROCESS FOR THEIR MANUFACTURE. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19792919324 DE2919324A1 (en) | 1979-05-14 | 1979-05-14 | DEHANIZER FOR RAW IRON AND STEEL MELTING AND A METHOD FOR THE PRODUCTION THEREOF |
| DE2919324 | 1979-05-14 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0019087A1 true EP0019087A1 (en) | 1980-11-26 |
| EP0019087B1 EP0019087B1 (en) | 1983-07-20 |
Family
ID=6070655
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP80101985A Expired EP0019087B1 (en) | 1979-05-14 | 1980-04-14 | Desulphurising agents for pig iron and steel melts, and process for their manufacture |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US4323392A (en) |
| EP (1) | EP0019087B1 (en) |
| JP (1) | JPS55158212A (en) |
| AT (1) | ATE4227T1 (en) |
| CA (1) | CA1141964A (en) |
| DE (2) | DE2919324A1 (en) |
| ES (1) | ES491528A0 (en) |
| NO (1) | NO153108C (en) |
| ZA (1) | ZA802836B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0031534B1 (en) * | 1979-12-29 | 1984-08-22 | Hoechst Aktiengesellschaft | Process for producing desulfurizing agents for pig iron or steel melts |
| EP0031552B1 (en) * | 1979-12-29 | 1984-11-21 | Hoechst Aktiengesellschaft | Desulphurising composition and process for its production |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2920353A1 (en) * | 1979-05-19 | 1980-11-27 | Hoechst Ag | METHOD FOR THE PRODUCTION OF DEHANIZING AGENTS FOR CRUDE IRON OR STEEL MELT |
| 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 |
| DE3111510A1 (en) * | 1981-03-24 | 1982-10-07 | Hoechst Ag, 6000 Frankfurt | DESULFURATION MIXTURE AND METHOD FOR THE PRODUCTION THEREOF |
| DE3908071A1 (en) * | 1989-03-13 | 1990-09-20 | Hoechst Ag | MEANS AND METHOD FOR DISCHARGING METAL MELTS |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2037758A1 (en) * | 1970-07-30 | 1972-02-03 | Knapsack Ag | Calcium carbide for desulphurisation - of molten metals improved by treatment with quick lime and fluorspar |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3666445A (en) * | 1967-12-26 | 1972-05-30 | Kaiser Ind Corp | Auxiliary composition for steel-making furnaces |
| DE1758250B1 (en) * | 1968-04-29 | 1971-10-28 | Sueddeutsche Kalkstickstoff | Agent for the desulphurisation of iron melts |
| DE1919414B2 (en) * | 1969-04-17 | 1977-07-14 | Hoechst Ag, 6000 Frankfurt | METHOD AND DEVICE FOR COOLING CALCIUM CARBIDE PICKED IN VESSELS |
| DE1935567B2 (en) * | 1969-07-12 | 1971-05-13 | Knapsack AG, 5033 Hurth Knapsack | PROCESS FOR THE PRODUCTION OF CALCIUM CARBIDE OF CERTAIN QUALITY |
| JPS554811B2 (en) * | 1973-06-13 | 1980-02-01 | ||
| DE2741588C2 (en) * | 1977-09-15 | 1985-02-07 | Skw Trostberg Ag, 8223 Trostberg | Agent for desulphurising molten iron |
-
1979
- 1979-05-14 DE DE19792919324 patent/DE2919324A1/en not_active Withdrawn
-
1980
- 1980-04-14 DE DE8080101985T patent/DE3064206D1/en not_active Expired
- 1980-04-14 EP EP80101985A patent/EP0019087B1/en not_active Expired
- 1980-04-14 AT AT80101985T patent/ATE4227T1/en not_active IP Right Cessation
- 1980-04-21 CA CA000350241A patent/CA1141964A/en not_active Expired
- 1980-05-09 US US06/148,565 patent/US4323392A/en not_active Expired - Lifetime
- 1980-05-13 NO NO801420A patent/NO153108C/en unknown
- 1980-05-13 ZA ZA00802836A patent/ZA802836B/en unknown
- 1980-05-13 JP JP6234480A patent/JPS55158212A/en active Granted
- 1980-05-14 ES ES491528A patent/ES491528A0/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2037758A1 (en) * | 1970-07-30 | 1972-02-03 | Knapsack Ag | Calcium carbide for desulphurisation - of molten metals improved by treatment with quick lime and fluorspar |
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| Title |
|---|
| PATENTS ABSTRACTS OF JAPAN, Band 1, NR. 120, 12. Oktober 1977, Seite 2840 C 78 & JP-A-53 099023. * |
| PATENTS ABSTRACTS OF JAPAN, Band 3, Nr. 11, 30. Januar 1979, Seite 75 C 35 & JP-A-53 134718. * |
| PATENTS ABSTRACTS OF JAPAN, Band 3, Nr. 133, 7. November 1979, Seite 70 C 63 & JP-A-54 112314. * |
| PATENTS ABSTRACTS OF JAPAN, Band 3, Nr. 75, 27. Juni 1979, Seite 63 C 50 & JP-A-54 050415. * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0031534B1 (en) * | 1979-12-29 | 1984-08-22 | Hoechst Aktiengesellschaft | Process for producing desulfurizing agents for pig iron or steel melts |
| EP0031552B1 (en) * | 1979-12-29 | 1984-11-21 | Hoechst Aktiengesellschaft | Desulphurising composition and process for its production |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3064206D1 (en) | 1983-08-25 |
| CA1141964A (en) | 1983-03-01 |
| ZA802836B (en) | 1981-06-24 |
| DE2919324A1 (en) | 1980-12-04 |
| EP0019087B1 (en) | 1983-07-20 |
| US4323392A (en) | 1982-04-06 |
| NO153108B (en) | 1985-10-07 |
| NO153108C (en) | 1986-01-15 |
| JPS55158212A (en) | 1980-12-09 |
| ES8101121A1 (en) | 1980-12-16 |
| JPS6353244B2 (en) | 1988-10-21 |
| NO801420L (en) | 1980-11-17 |
| ATE4227T1 (en) | 1983-08-15 |
| ES491528A0 (en) | 1980-12-16 |
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