EP0038417A1 - Desulfurising agent - Google Patents
Desulfurising agent Download PDFInfo
- Publication number
- EP0038417A1 EP0038417A1 EP81101765A EP81101765A EP0038417A1 EP 0038417 A1 EP0038417 A1 EP 0038417A1 EP 81101765 A EP81101765 A EP 81101765A EP 81101765 A EP81101765 A EP 81101765A EP 0038417 A1 EP0038417 A1 EP 0038417A1
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- EP
- European Patent Office
- Prior art keywords
- weight
- lime
- desulfurization
- quicklime
- agent according
- 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
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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
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/02—Dephosphorising or desulfurising
- C21C1/025—Agents used for dephosphorising or desulfurising
Definitions
- the invention relates to an agent for the desulfurization of pig iron.
- hot metal or steel can be desulfurized by adding quicklime to the molten iron.
- quicklime for example, when steel is being produced in the oxygen inflation converter, lime is added to bind sulfur.
- the object of the invention is therefore to provide a highly effective desulfurization agent which can be introduced into the pig iron to be treated with a smaller amount of conveying gas and thus enables less material losses and considerable energy savings through less cooling of the pig iron to be desulfurized.
- the agent according to the invention is preferably in powder form, which is obtained by grinding the components.
- the agent according to the invention preferably has a particle size suitable for pneumatic conveying.
- the diamide lime used as a component of the agent according to the invention is a chemically produced, precipitated calcium carbonate which has a carbon content of 5-40% by weight.
- the desulfurization agent according to the invention with a diamide lime content of about 40% by weight is particularly suitable for hot metal desulfurization in torpedo ladles.
- the desulfurizing agent according to the invention preferably has a diamide lime content of 15-25% by weight.
- the diamide lime contained in the desulfurization agent according to the invention has a carbon content of 5-50% by weight and preferably 10-40% by weight.
- the desulfurization agent according to the invention may further contain minor additions of conventional auxiliaries, for example a fluorspar content of up to 10% by weight.
- the desulfurizing agent according to the invention requires a significantly smaller amount of conveying gas than the quicklime used up to now for the same purpose.
- the agent according to the invention can be conveyed uniformly with a conveying gas amount of only 7 N1 per kg.
- the calcium carbonate portion of the diamide lime decomposes abruptly after it emerges from the lance through which the agent is introduced into the pig iron to be desulfurized, thereby ensuring intensive mixing of the solid desulfurizing agent with the iron melt to be treated.
- the calcium carbonate portion of the diamide lime initially becomes more reactive because freshly burned lime (CaO).
- the desulfurization agent according to the invention has the considerable advantage of a substantially improved reactivity compared to the lime used conventionally.
- the agent according to the invention which had been prepared by grinding 60% by weight of quicklime and 40% by weight of diamide lime with a carbon content of 20% by weight, was then used in the same plant to desulfurize the same pig iron.
- To achieve the same desulfurization effect only 4.8 kg of the desulfurization agent per ton of pig iron were required.
- the mixture could be pumped with little gas.
- For uniform, trouble-free blowing only 7 N1 of conveying gas per kg of the desulfurizing agent were necessary.
- the conveyor speed could therefore be increased to 100 kg per minute. Even at this higher blowing rate, only 700 N1 of conveying gas per minute were required. This corresponds to only about a fifth of the amount per unit of time for the promotion of the burnt lime was necessary. This resulted in a correspondingly lower turbulence of the melt.
- the pan was well filled, no ejection occurred.
- Another advantage of the desulphurizing agent according to the invention which can only be used in a smaller amount, and the possible higher conveying speed, is that the treatment of the 160 t of pig iron was finished after about 10 minutes, while the desulphurization treatment with quicklime lasts practically 1 hour. Such a long time is normally not available for desulfurization. A consequence of the lengthy treatment using large amounts when blowing in quicklime is still a strong cooling of the pig iron melt. For example, the temperature of the hot metal that was desulfurized with quicklime decreased by 42 ° C, while the temperature loss when using the desulfurization agent according to the invention was only 8 ° C.
- the desulfurizing agent according to the invention has surprising advantages over the commonly used quicklime.
Abstract
Description
Die Erfindung betrifft ein Mittel zur Entschwefelung von Roheisen.The invention relates to an agent for the desulfurization of pig iron.
Es ist bereits bekannt, daß man eine Entschwefelung von Roheisen oder Stahl durch Zugabe von gebranntem Kalk zu der Eisenschmelze bewirken kann. So wird beispielsweise bei der Erzeugung von Stahl im Sauerstoff-Aufblaskonverter Kalk zugegeben, um Schwefel abzubinden.It is already known that hot metal or steel can be desulfurized by adding quicklime to the molten iron. For example, when steel is being produced in the oxygen inflation converter, lime is added to bind sulfur.
Es ist weiterhin bekannt, den gebrannten Kalk in Pulverform einzublasen. Dies geschieht zum Beispiel im Elektro-Lichtbogenofen, im Sauerstoff-Aufblaskonverter (LDAC-Verfahren) und im bodenblasenden Konverter (OBM-Verfahren). Beim Einblasen von Kalk in Roheisentransportpfannen findet man, daß es notwendig ist, eine große Menge Kalk einzublasen um den gewünschten Entschwefelungseffekt zu erzielen. Weiterhin sind zur pneumatischen Förderung des Kalks große Mengen Fördergas notwendig (etwa 100 1 Gas pro kg des gebrannten Kalks), da es sonst zu Verstopfungen, einer Pfropfenbildung und einer ungleichmäßigen pneumatischen Förderung kommt. Dies ist jedoch unerwünscht, weil dies zum Spritzen und zu Metallauswürfen aus der Pfanne führt.It is also known to blow in the burnt lime in powder form. This is done, for example, in an electric arc furnace, in an oxygen inflation converter (LDAC process) and in a floor-blowing converter (OBM process). When blowing lime into pig iron transport pans, it is found that it is necessary to blow in a large amount of lime in order to achieve the desired desulfurization effect. Furthermore, large quantities of conveying gas are required for the pneumatic conveying of the lime (about 100 liters of gas per kg of the burned lime), since otherwise blockages, clogging and an uneven pneumatic conveying will occur. However, this is undesirable because it will cause splashing and metal ejection from the pan.
Es besteht daher ein Bedürfnis für ein Entschwefelungsmittel auf der Grundlage von gebranntem Kalk, das unter Anwendung geringerer Mengen Fördergas, beispielsweise mit 10 N1 Fördergas (10 1 Gas bei Normalbedingungen) pro kg Entschwefelungsmittel, gleichmäßig gefördert werden kann.There is therefore a need for a desulphurizing agent based on quicklime which can be evenly conveyed using smaller amounts of conveying gas, for example with 10 N1 conveying gas (10 1 gas under normal conditions) per kg of desulfurizing agent.
Die Aufgabe der Erfindung besteht somit darin, ein hochwirksames Entschwefelungsmittel anzugeben, das mit einer geringeren Menge Fördergases in das zu behandelnde Roheisen eingeführt werden kann und damit geringere Materialverluste und eine erhebliche Energieeinsparung durch geringere Abkühlung des zu entschwefelnden Roheisens ermöglicht.The object of the invention is therefore to provide a highly effective desulfurization agent which can be introduced into the pig iron to be treated with a smaller amount of conveying gas and thus enables less material losses and considerable energy savings through less cooling of the pig iron to be desulfurized.
Diese Aufgabe wird nun durch das erfindungsgemäße Mittel zur Entschwefelung von Roheisen oder Rohstahl gelöst, das gekennzeichnet ist, durch ein Gemisch aus gebranntem Kalk (CaO) und Diamidkalk.This object is now achieved by the agent according to the invention for the desulfurization of pig iron or crude steel, which is characterized by a mixture of quicklime (CaO) and diamide lime.
Das erfindungsgemäße Mittel liegt vorzugsweise in Pulverform vor, das man durch Vermahlen der Bestandteile erhält. Vorzugsweise besitzt das erfindungsgemäße Mittel eine für die pneumatische Förderung geeignete Teilchengröße.The agent according to the invention is preferably in powder form, which is obtained by grinding the components. The agent according to the invention preferably has a particle size suitable for pneumatic conveying.
Der als Bestandteil des erfindungsgemäßen Mittels verwendete Diamidkalk ist ein chemisch hergestelltes, gefälltes Calciumcarbonat, das einen Kohlenstoffgehalt von 5 - 40 Gew.-% aufweist.The diamide lime used as a component of the agent according to the invention is a chemically produced, precipitated calcium carbonate which has a carbon content of 5-40% by weight.
Das erfindungsgemäße Entschwefelungsmittel besteht vorzugsweise aus 50 - 90 Gew.-%, insbesondere 60 - 85 Gew.-% gebranntem Kalk und 10 - 50 Gew.-%, insbesondere 15 - 40 Gew.-% Diamidkalk. Gemäß einer besonders bevorzugten Ausführungsform enthält das erfindungsgemäße Entschwefelungsmittel etwa 40 Gew.-% (= 40 ± 3 Gew.-%) Diamidkalk.The desulfurization agent according to the invention preferably consists of 50-90% by weight, in particular 60-85% by weight, of quicklime and 10-50% by weight, in particular 15-40% by weight of diamide lime. According to a particularly preferred embodiment, the desulfurization agent according to the invention contains about 40% by weight (= 40 ± 3% by weight) of diamide lime.
Das erfindungsgemäße Entschwefelungsmittel mit einem Diamidkalkgehalt von etwa 40 Gew.-% (mit einem Kohlenstoffgehalt von 40 - 50 C-ew.-%) ist besonders geeignet für die Roheisenentschwefelung in Torpedopfannen. Für die Entschwefelung in offenen Roheisen-Transport- bzw. Charchierpfannen besitzt das erfindungsgemäße Entschwefelungsmittel vorzugsweise einen Diamidkalkgehalt von 15 - 25 Gew.-%.The desulfurization agent according to the invention with a diamide lime content of about 40% by weight (with a carbon content of 40-50 C-ew%) is particularly suitable for hot metal desulfurization in torpedo ladles. For desulfurization in open pig iron transport or charging pans, the desulfurizing agent according to the invention preferably has a diamide lime content of 15-25% by weight.
Der in dem erfindungsgemäßen Entschwefelungsmittel enthaltene Diamidkalk besitzt einen Kohlenstoffgehalt von 5 - 50 Gew.-% und vorzugsweise von 10 - 40 Gew.-%.The diamide lime contained in the desulfurization agent according to the invention has a carbon content of 5-50% by weight and preferably 10-40% by weight.
Das erfindungsgemäße Entschwefelungsmittel kann weiterhin kleinere Zusätze üblicher Hilfsmittel enthalten, beispielsweise einen Flußspatgehalt von bis zu 10 Gew.-%.The desulfurization agent according to the invention may further contain minor additions of conventional auxiliaries, for example a fluorspar content of up to 10% by weight.
Es hat sich überraschenderweise gezeigt, daß das erfindungsgemäße Entschwefelungsmittel eine wesentlich geringere Fördergasmenge benötigt als der bislang für den gleichen Zweck eingesetzte gebrannte Kalk. So läßt sich das erfindungsgemäße Mittel mit einer Fördergasmenge von lediglich 7 N1 pro kg gleichmäßig fördern. Dabei zersetzt sich der Calciumcarbonatanteil des Diamidkalks nach seinem Austritt aus der Lanze über die das Mittel in das zu entschwefelnde Roheisen eingeführt wird, schlagartig und sorgt dadurch für eine intensive Durchmischung des festen Entschwefelungsmittels mit der zu behandelnden Eisenschmelze. Dabei entsteht aus dem Calciumcarbonat-Anteil des Diamidkalks zunächst hochreaktiver, weil frisch gebrannter Kalk (CaO). Dadurch, daß dieses Gemisch in der Eisenschmelze Gas erzeugt, bilden sich sehr viele kleine Gasblasen mit sehr geringem Durchmesser. Dies hat zur Folge, daß nur eine sehr geringe Menge des erfindungsgemäßen Entschwefelungsmittels in relativ großen Blasen suspendiert und durch die Schmelze gefördert wird, ohne daß das Mittel mit dem Eisen in Kontakt kommt. Dies ist beim Betrachten der Oberfläche der Eisenschmelze während der Entschwefelungsbehandlung deutlich zu beobachten. So werden beim Einblasen von gebranntem Kalk in die Eisenschmelzegroße Blasen des Förder- gases an die Oberfläche geführt, die dort platzen und große Mengen von feinem, staubförmigem gebranntem Kalk freisetzen. Dieser Staub muß abgesaugt und mit Hilfe eines Filters oder eines Gaswäschers aus dem Abgas entfernt werden, was eine erhebliche Verteuerung der Entschwefelungsbehandlung mit sich bringt. Beim Einblasen des erfindungsgemäßen Entschwefelungsmittels werden keine großen Blasen an der Oberfläche der Eisenschmelze freigesetzt und es wird nur eine sehr geringe Staubentwicklung beobachtet.Surprisingly, it has been found that the desulfurizing agent according to the invention requires a significantly smaller amount of conveying gas than the quicklime used up to now for the same purpose. Thus, the agent according to the invention can be conveyed uniformly with a conveying gas amount of only 7 N1 per kg. The calcium carbonate portion of the diamide lime decomposes abruptly after it emerges from the lance through which the agent is introduced into the pig iron to be desulfurized, thereby ensuring intensive mixing of the solid desulfurizing agent with the iron melt to be treated. The calcium carbonate portion of the diamide lime initially becomes more reactive because freshly burned lime (CaO). Because this mixture produces gas in the molten iron, a large number of small gas bubbles with a very small diameter are formed. The result of this is that only a very small amount of the desulfurization agent according to the invention is suspended in relatively large bubbles and conveyed through the melt without the agent coming into contact with the iron. This is when looking at the surface of the molten iron during the desulfurization treatment to observe clearly. To be guided to the surface during injection of quicklime in the molten iron F Large bubbles of gas örder- which burst there and release large quantities of fine, dust-like quick lime. This dust must be suctioned off and removed from the exhaust gas with the aid of a filter or a gas scrubber, which makes the desulfurization treatment considerably more expensive. When the desulfurization agent according to the invention is blown in, no large bubbles are released on the surface of the molten iron and only very little dust is observed.
Das erfindungsgemäße Entschwefelungsmittel besitzt gegenüber dem herkömmlich eingesetzten Kalk den erheblichen Vorteil einer wesentlich verbesserten Reaktivität. So ist es bei Verwendung des erfindungsgemäßen Mittels zur Erzeugung des gleichen Entschwefelungseffektes überraschenderweise lediglich notwendig, nur etwa die Hälfte der Menge zuzusetzen, die bei der Behandlung mit gebranntem Kalk notwendig wäre.The desulfurization agent according to the invention has the considerable advantage of a substantially improved reactivity compared to the lime used conventionally. When using the agent according to the invention to produce the same desulfurization effect, it is surprisingly only necessary to add only about half the amount that would be necessary in the treatment with quicklime.
Dieser überraschende Vorteil der wesentlich besseren Reaktivität bzw. des höheren Wirkungsgrades manifestiert sich auch darin, daß wegen der Verringerung der Menge des einzublasenden Entschwefelungsmittels eine entsprechend geringere Menge Entschwefelungsschlacke anfällt. Die Entschwefelungsschlacke enthält stets noch einen hohen Anteil an metallischem Eisen, der bis zu 50 Gew.-% betragen kann. Dieses in der Entschwefelungsschlacke enthaltende Eisen geht zunächst aus der Pfanne verloren, kann erst aus der erstarrten Schlacke wieder unter beträchtlichem Aufwand zurückgewonnen werden. Insbesondere wenn die Schlacke stärker abkühlt, beispielsweise dann, wenn sie nicht unmittelbar nach der Behandlung entfernt wird, kann dies auch dazu führen, daß sie zum Teil in dem Behandlungsgefäß verbleibt, wodurch dessen Transportkapazität für die flüssige Metallschmelze verringert wird.This surprising advantage of the substantially better reactivity or the higher efficiency is also manifested in the fact that a correspondingly smaller amount of desulfurization slag is produced because of the reduction in the amount of desulfurization agent to be blown in. The desulfurization slag still contains a high proportion of metallic iron, which can be up to 50% by weight. This iron contained in the desulfurization slag is initially lost from the pan and can only be recovered from the solidified slag with considerable effort. In particular, if the slag cools down more, for example if it is not removed immediately after the treatment, this can also result in some of it remaining in the treatment vessel, thereby reducing its transport capacity for the molten metal.
Das folgende Beispiel dient der weiteren Erläuterung des erfindungsgemäßen Mittel im Vergleich zu dem herkömmlich eingesetzten gebrannten Kalk.The following example serves to further explain the agent according to the invention in comparison with the conventionally used quicklime.
In einer Torpedopfanne wurden 160 t Roheisen mit reinem gebranntem Kalk entschwefelt. Der Anfangsschwefelgehalt des Roheisens betrug 0,042 Gew.-%. Mit Hilfe einer etwa 1,6 m tief in die Schmelze eingetauchten Lanze wurden insgesamt 1760 kg gebrannter Feinkalk eingeblasen. Um eine einigermaßen gleichmäßige Förderung zu erzielen mußten 120 N1 Fördergas pro kg gebrannten Kalks aufgewandt werden. Durch diese großen Gasmengen kam es zu heftigen Aufwallungen der Metallschmelze, wobei größere Mengen Metall aus der Pfanne spritzten. Dabei stiegen aus der Mündung der Pfanne dicke Wolken weißen Rauches auf. Um das Spritzen nicht zu heftig werden zu lassen konnten pro Minute nur 30 kg gebrannter Kalk mit 3600 N1 Fördergas eingeblasen werden. Der Endschwefelgehalt des Roheisens betrug 0,018 Gew.-% S.In a torpedo pan, 160 t of pig iron was desulphurized with pure burnt lime. The initial sulfur content of the pig iron was 0.042% by weight. With the help of a lance immersed approximately 1.6 m deep, a total of 1760 kg of burned fine lime was blown in. In order to achieve a reasonably uniform production, 120 N1 production gas per kg of burnt lime had to be used. These large amounts of gas caused violent ripples in the molten metal, with larger amounts of metal spraying out of the pan. Thick clouds of white smoke rose from the mouth of the pan. In order not to make the spraying too violent, only 30 kg of burnt lime with 3600 N1 conveying gas could be blown in per minute. The final sulfur content of the pig iron was 0.018% by weight of S.
In der gleichen Anlage wurde anschließend das erfindungsgemäße Mittel, das durch Vermahlen von 60 Gew.-% gebranntem Kalk und 40 Gew.-% Diamidkalk mit einem Kohlenstoffgehalt von 20 Gew.-% hergestellt worden war, verwendet, um das gleiche Roheisen zu entschwefeln. Zur Erzielung der gleichen Entschwefelungswirkung waren lediglich 4,8 kg des Entschwefelungsmittels pro t Roheisen nötig. Das Gemisch konnte dabei gasarm gefördert werden. Zum gleichmäßigen störungsfreien Einblasen waren lediglich 7 N1 Fördergas pro kg des Entschwefelungsmittels notwendig. Die Fördergeschwindigkeit konnte deshalb auf 100 kg pro Minute erhöht werden. Selbst bei dieser höheren Blasrate waren lediglich 700 N1 Fördergas pro Minute nötig. Dies entspricht lediglich etwa einem Fünftel der Menge pro Zeiteinheit, die für die Förderung des gebrannten Kalkes notwendig war. Dabei ergab sich eine entsprechend geringere Turbulenz der Schmelze. Wenngleich die Pfanne gut gefüllt war, traten keine Auswürfe auf.The agent according to the invention, which had been prepared by grinding 60% by weight of quicklime and 40% by weight of diamide lime with a carbon content of 20% by weight, was then used in the same plant to desulfurize the same pig iron. To achieve the same desulfurization effect, only 4.8 kg of the desulfurization agent per ton of pig iron were required. The mixture could be pumped with little gas. For uniform, trouble-free blowing, only 7 N1 of conveying gas per kg of the desulfurizing agent were necessary. The conveyor speed could therefore be increased to 100 kg per minute. Even at this higher blowing rate, only 700 N1 of conveying gas per minute were required. This corresponds to only about a fifth of the amount per unit of time for the promotion of the burnt lime was necessary. This resulted in a correspondingly lower turbulence of the melt. Although the pan was well filled, no ejection occurred.
Ein weiterer Vorteil des lediglich in geringerer Menge einzusetzenden erfindungsgemäßen Entschwefelungsmittel und der möglichen höheren Fördergeschwindigkeit ist darin zu sehen, daß die Behandlung der 160 t Roheisen nach etwa 10 Minuten beendet war, während die Entschwefelungsbehandlung mit gebranntem Kalk praktisch 1 Stunde dauert. Eine derart lange Zeit steht normalerweise nicht für die Entschwefelung zur Verfügung. Eine Konsequenz der langwierigen Behandlung unter Anwendung großer Mengen beim Einblasen von gebranntem Kalk ist weiterhin eine starke Abkühlung der Roheisenschmelze. So sank die Temperatur der mit gebranntem Kalk entschwefelten Roheisenschmelze um 42°C ab, während der Temperaturverlust bei der Verwendung des erfindungsgemäßen Entschwefelungsmittels lediglich 8°C betrug.Another advantage of the desulphurizing agent according to the invention, which can only be used in a smaller amount, and the possible higher conveying speed, is that the treatment of the 160 t of pig iron was finished after about 10 minutes, while the desulphurization treatment with quicklime lasts practically 1 hour. Such a long time is normally not available for desulfurization. A consequence of the lengthy treatment using large amounts when blowing in quicklime is still a strong cooling of the pig iron melt. For example, the temperature of the hot metal that was desulfurized with quicklime decreased by 42 ° C, while the temperature loss when using the desulfurization agent according to the invention was only 8 ° C.
Damit ist ersichtlich, daß das erfindungsgemäße Entschwefelungsmittel im Vergleich zu dem üblicherweise verwendeten gebrannten Kalk überraschende Vorteile aufweist.It can thus be seen that the desulfurizing agent according to the invention has surprising advantages over the commonly used quicklime.
Claims (7)
besteht.2. Composition according to claim 1, characterized in that it consists of
consists.
besteht.3. Means according to claims 1 or 2, characterized in that it consists of
consists.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT81101765T ATE10650T1 (en) | 1980-04-18 | 1981-03-10 | DESULPHURIZATION AGENT. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3015024A DE3015024C2 (en) | 1980-04-18 | 1980-04-18 | Desulphurising agents for pig iron |
| DE3015024 | 1980-04-18 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0038417A1 true EP0038417A1 (en) | 1981-10-28 |
| EP0038417B1 EP0038417B1 (en) | 1984-12-05 |
Family
ID=6100415
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP81101765A Expired EP0038417B1 (en) | 1980-04-18 | 1981-03-10 | Desulfurising agent |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0038417B1 (en) |
| JP (1) | JPS56158807A (en) |
| AT (1) | ATE10650T1 (en) |
| CA (1) | CA1171663A (en) |
| DE (2) | DE3015024C2 (en) |
| ES (1) | ES501153A0 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2590905A1 (en) * | 1985-12-03 | 1987-06-05 | Centro Speriment Metallurg | PROCESS FOR CONTINUOUS PURIFICATION OF FUSION CAST IRON |
| EP0602540A1 (en) * | 1992-12-15 | 1994-06-22 | Alfred Dr.-Ing. Freissmuth | Agent for desulphurization, dephosphorization, desiliconization and denitrification of molten pig or cast iron and of molten ferrochrome or ferromanganese as well as a process |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56158827A (en) * | 1980-05-10 | 1981-12-07 | Nippon Carbide Ind Co Ltd | Powdered composition for desulfurizing agent |
| JPS58204119A (en) * | 1982-05-25 | 1983-11-28 | Nippon Carbide Ind Co Ltd | Desulfurizing agent for molten iron |
| ATE37902T1 (en) * | 1984-06-28 | 1988-10-15 | Thyssen Stahl Ag | PIG IRON DESULPHURIZATION PROCESS. |
| US6989040B2 (en) | 2002-10-30 | 2006-01-24 | Gerald Zebrowski | Reclaimed magnesium desulfurization agent |
| JP5653741B2 (en) | 2010-12-15 | 2015-01-14 | タカタ株式会社 | Buckle and seat belt device provided with the same |
| DE102011116501C5 (en) * | 2011-10-20 | 2018-05-24 | Almamet Gmbh | Bitumen-containing desulphurising agent |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1583268B1 (en) * | 1967-12-29 | 1971-08-05 | Konink Nl Hoogovens En Staalfa | Means for the desulphurisation of liquid iron based on technical calcium cyanamide and a process for the desulphurisation of iron |
-
1980
- 1980-04-18 DE DE3015024A patent/DE3015024C2/en not_active Expired
-
1981
- 1981-02-24 CA CA000371607A patent/CA1171663A/en not_active Expired
- 1981-03-10 AT AT81101765T patent/ATE10650T1/en not_active IP Right Cessation
- 1981-03-10 EP EP81101765A patent/EP0038417B1/en not_active Expired
- 1981-03-10 DE DE8181101765T patent/DE3167539D1/en not_active Expired
- 1981-04-07 ES ES501153A patent/ES501153A0/en active Granted
- 1981-04-14 JP JP5518581A patent/JPS56158807A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1583268B1 (en) * | 1967-12-29 | 1971-08-05 | Konink Nl Hoogovens En Staalfa | Means for the desulphurisation of liquid iron based on technical calcium cyanamide and a process for the desulphurisation of iron |
Non-Patent Citations (2)
| Title |
|---|
| PATENTS ABSTRACTS OF JAPAN, Band 3, Nr. 109(C-58), 12. September 1979, seite 14C58 & JP-A-54 086 417 (07-10-1979) * Abstract * * |
| PATENTS ABSTRACTS OF JAPAN, Band 3, Nr. 75(C50), 27. Juni 1979, seite 63C50 & JP-A-54 050 414 (20-04-1979) * Abstract * * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2590905A1 (en) * | 1985-12-03 | 1987-06-05 | Centro Speriment Metallurg | PROCESS FOR CONTINUOUS PURIFICATION OF FUSION CAST IRON |
| EP0602540A1 (en) * | 1992-12-15 | 1994-06-22 | Alfred Dr.-Ing. Freissmuth | Agent for desulphurization, dephosphorization, desiliconization and denitrification of molten pig or cast iron and of molten ferrochrome or ferromanganese as well as a process |
Also Published As
| Publication number | Publication date |
|---|---|
| ATE10650T1 (en) | 1984-12-15 |
| DE3167539D1 (en) | 1985-01-17 |
| JPS56158807A (en) | 1981-12-07 |
| EP0038417B1 (en) | 1984-12-05 |
| ES8205867A1 (en) | 1982-07-01 |
| DE3015024C2 (en) | 1982-12-23 |
| DE3015024A1 (en) | 1981-10-29 |
| CA1171663A (en) | 1984-07-31 |
| ES501153A0 (en) | 1982-07-01 |
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