EP1507876B1 - Verfahren zum metallurgischen behandeln einer metallschmelze - Google Patents

Verfahren zum metallurgischen behandeln einer metallschmelze Download PDF

Info

Publication number
EP1507876B1
EP1507876B1 EP03740486A EP03740486A EP1507876B1 EP 1507876 B1 EP1507876 B1 EP 1507876B1 EP 03740486 A EP03740486 A EP 03740486A EP 03740486 A EP03740486 A EP 03740486A EP 1507876 B1 EP1507876 B1 EP 1507876B1
Authority
EP
European Patent Office
Prior art keywords
treatment
metal bath
bell
slag
molten metal
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.)
Expired - Lifetime
Application number
EP03740486A
Other languages
English (en)
French (fr)
Other versions
EP1507876A2 (de
Inventor
Jean-Luc Roth
Emile Lonardi
Paul Berg
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Paul Wurth SA
Original Assignee
Paul Wurth SA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Paul Wurth SA filed Critical Paul Wurth SA
Publication of EP1507876A2 publication Critical patent/EP1507876A2/de
Application granted granted Critical
Publication of EP1507876B1 publication Critical patent/EP1507876B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • C21C7/0075—Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle
    • 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
    • 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
    • C21C7/005—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using exothermic reaction compositions
    • 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
    • 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
    • C21C7/072—Treatment with gases

Definitions

  • the present invention relates generally to a method of metallurgical treatments on a metal bath. It relates more particularly to such a process which comprises a first treatment involving the presence or the formation of an acidic slag on the surface of a metal bath and a second treatment involving the presence or the formation of a basic slag on the surface of this bath. metallic.
  • a method of this type is for example a method for treating the raw steel in a pocket in which the steel bath is heated by aluminothermy before carrying out a desulphurization treatment (that is to say a treatment for lowering sulfur content) and / or dephosphorization (i.e., a treatment for lowering phosphorus content).
  • a desulphurization treatment that is to say a treatment for lowering sulfur content
  • dephosphorization i.e., a treatment for lowering phosphorus content.
  • aluminum is reacted with oxygen to form an acidic slag of Al 2 O 3 at the surface of the steel bath.
  • the desulphurization or dephosphorization treatment which requires a basic slag on the surface of the steel bath, is inhibited by the presence of an acidic Al 2 O 3 slag on the surface of the steel bath.
  • the acid slag of Al2O3 must first be removed before the desulfurization and / or dephosphorination treatment can be started.
  • an intermediate scrubbing significantly increases the total duration of the treatment and is not possible in any metallurgical treatment stand.
  • the bell When the aluminothermic heating is finished, the bell is removed.
  • the slag around the bell mixes with the slag Al2O3 formed below the bell, which gives a slag whose content inhibits a desulfurization treatment and / or subsequent dephosphorization by its high content of Al2O3 (> 40%) .
  • Another method of the kind defined in the preamble is a method in which a pig iron bath or a ferroalloy bath must undergo both oxygen injection desiliconization (i.e., treatment to lower silicon content) and desulfurization and / or dephosphorization. Desiliconization by oxygen injection produces an acid SiO 2 slag on the surface of the metal bath. However, the subsequent desulfurization treatment requires the presence of a basic slag on the surface of the steel bath and is inhibited by an SiO 2 content greater than 10%. It follows that the acidic slag formed during the desiliconization must be cleared before starting the desulphurization treatment. As already explained, such an intermediate scrubbing substantially increases the duration of the process and is not possible in any metallurgical treatment stand.
  • oxygen injection desiliconization i.e., treatment to lower silicon content
  • desulfurization and / or dephosphorization Desiliconization by oxygen injection produces an acid SiO 2 slag on the surface of the metal bath.
  • the object of the present invention is to optimize the progress of a metallurgical process in which a first treatment involves the presence or the formation of an acidic slag on the surface of a metal bath and a second treatment involves the presence or the formation of a basic slag on the surface of this metal bath.
  • this objective is achieved by carrying out the two treatments without intermediate scrubbing simultaneously in two separate zones and ensuring on the surface of the metal bath a physical separation between an acid slag zone and a basic slag zone.
  • both treatments will take place simultaneously. It will be appreciated that in all these cases the time necessary for the intermediate slagging is spared and the two treatments can be carried out in a single metallurgical treatment stand which is not necessarily equipped to carry out a slag removal (the final scrubbing can take place do elsewhere).
  • one of the two treatments is performed under a deep bell whose lower edge is immersed in the metal bath and the other treatment is performed around this deep bell.
  • This deep bell ensures the physical separation between the two slag areas on the surface of the bath, while allowing one of the two treatments to be carried out under a protected atmosphere, with a minimum of losses to the environment.
  • This separation wall can either cooperate with the edges of a metallurgical vessel to divide the surface of the metal bath into two juxtaposed zones, or form a kind of ring to delimit an "island" inside the surface of the metal bath. .
  • the first treatment is for example a chemical reheating which is carried out under a deep bell under a protected atmosphere and which produces an acidic slag under this bell.
  • chemical heating is meant here a strongly exothermic oxidation of a generally metallic element, such as that for example aluminum (aluminothermie) or silicon (silicothermie).
  • the first treatment can also be a desiliconation treatment by oxygen injection, especially in the context of a treatment of cast iron or ferroalloys (such as ferro-nickel) with high levels of silicon.
  • This desiliconation treatment by oxygen injection is also advantageously carried out under a deep bell whose lower edge is immersed in the metal bath.
  • the second treatment is for example a desulfurization and / or dephosphorization treatment using a basic slag, formed for example by adding lime, sodium carbonate, magnesium etc. This treatment can be carried out around the deep bell under which the first treatment is performed.
  • the desulphurization and / or dephosphorination treatment advantageously comprises the addition of limestone, in particular of limestone, to the metal bath. It is a cheap and highly effective desulfurizing agent, but its decomposition in the metal bath gives rise to a highly endothermic reaction which tends to cool the metal bath. However, in combination with desiliconization by oxygen injection, this cooling effect is hardly a problem, because the desiliconation reaction, which is highly exothermic, anyway produces an excess of heat.
  • a deep bell When a deep bell is used to ensure a physical separation on the surface of the metal bath between an acidic slag zone and a basic slag zone, the following procedure is advantageously performed: firstly, by injection of an inert gas, a "window" in an initial slag layer covering the surface of the metal bath; this "window” is covered with a deep bell whose lower edge is immersed in the metal bath; one of the two treatments is carried out under the deep bell and the other around the deep bell, simultaneously mixing the metal bath by injecting an inert gas; and at the end of both treatments, stop the brewing, remove the deep bell and clean up immediately after the two slags. Stopping the stirring before removal of the deep bell prevents the two slags from mixing too much, which could be detrimental to the outcome of the process.
  • FIG. 1 shows a schematic illustration of the implementation of the implementation of a method according to the invention.
  • Fig. 1 is used to further describe, by way of illustration of the present invention, the course of a metallurgical process which comprises a pocket desulfurization treatment of a crude steel bath, preceded by a chemical warming in pocket of this steel bath.
  • FIG. 1 shows a metallurgical pocket 10 in a metallurgical treatment stand during the implementation of the aforementioned method.
  • this pocket 10 contained a crude steel bath 12 from the converter or electric furnace, as well as a basic residual slag layer covering the steel bath.
  • a window 14 has initially been formed by injection of an inert gas into the residual slag layer, that is to say that an area of the surface of the bath has been released. at least partially of the residual slag which covered it.
  • a deep bell 16 has then been positioned, so that its lower edge 18 is immersed in the metal bath 12 by at least 20 cm (the sparging of the metal bath 12 is important, the deeper the depth of the lower edge of the bell 16 will be important). It remains to be noted that a possible embodiment of such a deep bell 16 is for example described in the patent application WO 98/31841, while specifying, however, that the bell used in the present process need not necessarily be a bell. rotating bell.
  • the steel bath is heated by aluminothermy.
  • aluminum is added and oxygen is blown under the bell 16, as indicated schematically by the arrows 18 and 20.
  • the metal bath 12 is stirred with a gas inert, which is injected, preferably with the aid of a lateral lance 22, into the metal bath 12.
  • the aluminum reacts in a strongly exothermic reaction with oxygen. This reaction results in the formation of an acid slag of Al 2 O 3 below the bell 16.
  • this acid slag Al2O3 is identified by the reference 24.
  • the bell 16 was raised at the end of the chemical reheating in order to carry out a slag removal of the highly contaminated residual slag with the slag Al2O3 formed under the bell 16. Thereafter, the desulphurization treatment was carried out on the bath. steel released from slag. Indeed, it is known that in order to perform a desulfurization treatment and / or dephosphorization using a basic slag, it is necessary that the Al2O3 content of this slag is less than 40%.
  • the desulfurization and / or dephosphorization treatment is carried out around the bell 16 without performing an intermediate slag removal.
  • a basic slag forming agent 28 is injected into the metal bath 12 around the bell 16.
  • This agent for forming a basic slag 28 may, for example, be lime, limestone, limestone, soda ash, magnesium etc.
  • the bell 16 prevents the acid slag of Al2O3 formed under the bell 16 from mixing with the basic slag surrounding the pocket 16, which allows perform both treatments simultaneously without intermediate scrubbing.
  • the aluminothermic heating is started first and the desulfurization and / or dephosphorization treatment is started as soon as the steel bath has reached a sufficient temperature.
  • the treatment carried out under the bell could for example also be a desilicon treatment of cast iron or ferroalloys, especially ferro-nickel, by oxygen injection.
  • the silicon reacts with the blown oxygen below the bell to form an acid SiO 2 slag under the bell.
  • Around the bell can then perform a desulphurization treatment and / or dephosphorization as described above.
  • the bell prevents the acid SiO 2 slag formed under the bell 16 from mixing with the basic slag surrounding the pocket 16, which makes it possible to perform the two treatments simultaneously without intermediate scrubbing.
  • the SiO 2 content of the basic slag must not be greater than 10%.
  • This example relates to a pocket treatment of the crude steel converter with the objective of desulphurizing at 80% of this steel.
  • a metallurgical ladle contains 160 t of crude steel converter and 600 kg of residual slag.
  • the analysis results are as follows: 0.04% C, 600 ppm O, 0.010% S.
  • the temperature of the steel bath is 1600 ° C. 200 kg of deoxidizing Al and 600 kg of CaO were added to the casting.
  • the first treatment is an aluminothermic heating which is carried out, as described with reference to FIG. 1, under a deep bell positioned above an area of the steel bath previously released from its residual slag layer.
  • An increase in temperature of the steel bath of about 90 ° C is obtained by injection of 530 kg of aluminum and 350 m3 of oxygen in 7 minutes (flow rate of 50 m3 / min of O 2). Brewing below the bell is done by injecting argon using a side lance with a flow rate of 0.2 m3 / min.
  • Desulfurization The second treatment is an 80% high desulfurization that takes place around the bell.
  • desulfurizing agent a powder composed of 60% CaO and 35% Al2O3, the remainder being impurities.
  • Al2O3 is intended to regulate the fluidity of the slag obtained.
  • Other slag agents can also be added.
  • the desulfurizing agent is injected using a submerged head lance, using argon as the carrier gas.
  • the injection lance is used to perform a prior stirring of the steel bath.
  • the injection lance is fed for 5 minutes with a flow rate of approximately 0.5 m3 / min of argon, the feed of the desulfurizing agent being cut off.
  • This preliminary stirring makes it possible in particular to homogenize the temperature of the steel bath before its desulfurization.
  • 960 kg of the above-mentioned desulphurizing agent solid flow rate about 80 kg / min
  • the treatment is terminated by carrying out with the same lance for 5 minutes an intense stirring with a flow rate of approximately 1 m3 / min of argon, the supply of desulfurizing agent being cut again. Then we stop all brewing and we go up the bell.
  • Dairy about 1000 kg of Al2O3 formed under the bell, plus about 2500 kg of desulfurizing slag around the bell.
  • the residual slag which is found around the bell, can already contain a sufficient amount of desulfurizing agents to obtain a moderate desulphurization of the steel. It is then sufficient to stir the steel bath around the bell to react with the residual slag floating on its surface and to add, if necessary, more slag agents to adjust in particular the consistency of the slag.
  • This example concerns a raw pig pocket treatment with the aim of desilicating and desulfurizing the cast iron.
  • a metallurgical ladle contains 100 t of pig iron, the analysis results of which are as follows: 4.5% C, 0.8% Si, 0.10% S. The temperature of the melt bath is 1350 ° C . The cast iron is covered with a residual slag layer of basic character.
  • Desiliconization treatment A desiliconization treatment by oxygen injection is carried out, as described above, under a deep bell positioned above a zone of the bath previously released from its residual slag layer. 450 m3 of oxygen are injected under the bell in 10 minutes (flow rate 45 m3 / min of 02). Brewing below the bell is done by injecting argon using a side lance with a flow rate of 0.2 m3 / min.
  • Desulfurization takes place around the bell.
  • desulfurizing agent a powder composed of 70% CaCO3 and 30% Na2CO3.
  • Other slag agents can also be added.
  • the desulfurizing agent is injected using a submerged lance, using argon as a carrier gas.
  • About 1000 kg of the above-mentioned desulfurizing agent (solid flow rate about 50 kg / min) are injected over a period of about 20 minutes with about 1 m3 / min of argon as the carrier gas. After stopping all brewing, you can put the bell up and clean the two slags together.
  • Pretreated iron 4.3% C, 0.4% Si, 0.02% S, temperature around 1400 ° C.
  • Dairy about 860 kg of SiO2 formed under the bell, plus about 700 kg of desulfurizing slag around the bell.
  • a Mg-CaCl 2 or Mg-CaO mixture is most often used as desulfurizer. These are very effective desulphurizers, but also very expensive. They are mainly used because they produce a limited cooling of the metal bath.
  • desulfurizing agent such as, for example, limestone (CaCO3) or limestone.
  • the decomposition of CaCO3 or Na2CO3 in the steel bath also generates oxygen, which contributes to the desiliconization of the melt (1 kg CaCO3 or Na2CO3 reduces the desilicon oxygen requirement by approximately 0.1 m3).
  • a ferroalloy bath in particular a ferro-nickel bath, may also be subjected to a combined desiliconization and desulphurization treatment, as presented in Example 2 for melting.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Coating With Molten Metal (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Claims (10)

  1. Verfahren zur metallurgischen Behandlung einer Metallschmelze, umfassend
    eine erste Behandlung, welche das Vorhandensein oder die Bildung einer sauren Schlacke auf der Oberfläche der Metallschmelze impliziert; und
    eine zweite Behandlung, welche das Vorhandensein oder die Bildung einer basischen Schlacke auf der Oberfläche der Metallschmelze impliziert;
    dadurch gekennzeichnet, dass beide Behandlungen ohne Zwischenabschlacken gleichzeitig in zwei getrennten Zonen durchgeführt werden und dabei auf der Oberfläche der Metallschmelze eine physische Trennung zwischen einer sauren Schlackenzone und einer basischen Schlackenzone sichergestellt wird
  2. Verfahren nach Anspruch 1, bei dem eine der beiden Behandlungen unter einer tiefen Glocke durchgeführt wird, deren unterer Rand in der Metallschmelze eingetaucht ist, und die andere Behandlung um die tiefe Glocke herum durchgeführt wird.
  3. Verfahren nach Anspruch 2, bei dem die erste Behandlung eine chemische Heizbehandlung ist, die unter der tiefen Glocke durchgeführt wird
  4. Verfahren nach Anspruch 3, bei dem die chemische Heizbehandlung eine Aluminothermie- oder Silicothermiebehandlung ist.
  5. Verfahren nach irgendeinem der Ansprüche 1 bis 4, bei dem die zweite Behandlung eine Entschwefelungs- und/oder Entphosphorungsbehandlung auf der Basis einer basischen Schlacke ist
  6. Verfahren nach Anspruch 1, bei dem die erste Behandlung eine Behandlung zur Entsilicierung von Gusseisen oder Ferrolegierungen, insbesondere Ferronickel, durch Einblasen von Sauerstoff ist
  7. Verfahren nach Anspruch 6, bei dem die Entsilicierungsbehandlung durch Einblasen von Sauerstoff unter einer tiefen Glocke durchgeführt wird, deren unterer Rand in der Metallschmelze eingetaucht ist, und die zweite Behandlung eine Entschwefelungs- und/oder Entphosphorungsbehandlung ist, die um die tiefe Glocke herum durchgeführt wird
  8. Verfahren nach irgendeinem der Ansprüche 6 oder 7, bei dem die zweite Behandlung eine Entschwefelungs- und/oder Entphosphorungsbehandlung auf der Basis von Kalk ist
  9. Verfahren nach Anspruch 8, bei dem die zweite Behandlung den Zusatz von Kalkstein, insbesondere von Zuschlagkalkstein zur Metallschmelze umfasst
  10. Verfahren nach irgendeinem der Ansprüche 1 bis 9, bei dem:
    zu Beginn des Verfahrens die Oberfläche der Metallschmelze mit einer Schicht Restschlacke bedeckt ist;
    in der Schicht Restschlacke durch Einblasen eines Inertgases ein Fenster ausgebildet wird;
    das Fenster mit einer tiefen Glocke bedeckt wird, deren unterer Rand in der Metallschmelze eingetaucht ist;
    eine der beiden Behandlungen unter der tiefen Glocke und die andere um die tiefe Glocke herum durchgeführt wird und dabei gleichzeitig eine Durchmischung der Schmelze durch Einblasen eines Inertgases durchgeführt wird; und
    am Ende der beiden Behandlungen die Durchmischung eingestellt wird, die tiefe Glocke entfernt wird und unmittelbar danach die beiden Schlacken abgezogen werden
EP03740486A 2002-05-24 2003-05-21 Verfahren zum metallurgischen behandeln einer metallschmelze Expired - Lifetime EP1507876B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
LU90924 2002-05-24
LU90924A LU90924B1 (fr) 2002-05-24 2002-05-24 Procédé de traitements métallurgiques sur bain métallique
PCT/EP2003/050183 WO2003100102A2 (fr) 2002-05-24 2003-05-21 Procédé de traitements métallurgiques sur bain métallique

Publications (2)

Publication Number Publication Date
EP1507876A2 EP1507876A2 (de) 2005-02-23
EP1507876B1 true EP1507876B1 (de) 2006-10-04

Family

ID=29580011

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03740486A Expired - Lifetime EP1507876B1 (de) 2002-05-24 2003-05-21 Verfahren zum metallurgischen behandeln einer metallschmelze

Country Status (12)

Country Link
EP (1) EP1507876B1 (de)
JP (1) JP4405381B2 (de)
KR (1) KR100926321B1 (de)
CN (1) CN1665942B (de)
AU (1) AU2003273150B2 (de)
BR (1) BR0311295B1 (de)
CA (1) CA2485633A1 (de)
DE (1) DE60308860T2 (de)
ES (1) ES2273014T3 (de)
LU (1) LU90924B1 (de)
RU (1) RU2289630C2 (de)
WO (1) WO2003100102A2 (de)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102115800B (zh) * 2011-01-14 2013-03-13 河北钢铁股份有限公司承德分公司 一种钒铁合金清洁生产工艺

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3971655A (en) * 1974-08-21 1976-07-27 Nippon Steel Corporation Method for treatment of molten steel in a ladle
DE2629020C2 (de) * 1976-06-29 1985-06-20 Nippon Steel Corp., Tokio/Tokyo Verfahren zum entphosphorn von metallen und legierungen
LU84472A1 (fr) * 1982-11-17 1984-06-13 Arbed Procede et installation pour le traitement de l'acier en poche
JPS6465226A (en) * 1987-09-04 1989-03-10 Sumitomo Metal Ind Ladle refining method
CN1087034C (zh) * 1999-11-02 2002-07-03 北京科技大学 盛钢桶浸渍罩密闭钢液喷粉脱硫方法及装置

Also Published As

Publication number Publication date
RU2004138075A (ru) 2006-01-20
RU2289630C2 (ru) 2006-12-20
KR20040106583A (ko) 2004-12-17
WO2003100102A3 (fr) 2004-02-26
CN1665942A (zh) 2005-09-07
EP1507876A2 (de) 2005-02-23
ES2273014T3 (es) 2007-05-01
JP4405381B2 (ja) 2010-01-27
KR100926321B1 (ko) 2009-11-12
JP2005531687A (ja) 2005-10-20
AU2003273150A1 (en) 2003-12-12
DE60308860T2 (de) 2007-02-22
AU2003273150B2 (en) 2009-01-08
LU90924B1 (fr) 2003-11-25
DE60308860D1 (de) 2006-11-16
CA2485633A1 (fr) 2003-12-04
CN1665942B (zh) 2011-05-11
WO2003100102A2 (fr) 2003-12-04
BR0311295B1 (pt) 2012-07-10
BR0311295A (pt) 2005-04-19

Similar Documents

Publication Publication Date Title
JP5418733B2 (ja) 溶銑の精錬方法
FR2564863A1 (fr) Procede d'elaboration d'un alliage ferreux a haute teneur en manganese par fusion reductrice.
JP2011144415A (ja) 転炉精錬方法
WO2008068916A1 (ja) 極低硫低窒素高清浄度鋼の溶製方法
JP6645374B2 (ja) 極低硫低窒素鋼の溶製方法
KR100728130B1 (ko) 전로 정련 방법
EP1507876B1 (de) Verfahren zum metallurgischen behandeln einer metallschmelze
EP2252712B1 (de) Neuartiger zusatz zur bearbeitung von sulfurisiertem stahl
KR100985308B1 (ko) 극저황 고청정 강의 제조 방법
TWI699436B (zh) 鋼之製造方法
JPH0437136B2 (de)
KR101028914B1 (ko) 극저황 고청정 강의 용제 방법
JPH0841516A (ja) 予備精錬方法
JP2009052070A (ja) 溶銑脱りん処理方法
RU2156811C1 (ru) Способ производства железоуглеродистого расплава для получения стали
JP2005133117A (ja) 低燐溶銑の製造方法
BE1003182A4 (fr) Procede de fabrication de l'acier d'usage courant.
JP2006138003A (ja) 溶銑の処理方法
JP2005248219A (ja) 溶銑の予備処理方法
BE879594A (fr) Procede de fabrication d'acier
BE525616A (de)
JP2000073114A (ja) 溶銑の脱珪方法
JP2005248218A (ja) 溶銑の予備処理方法
JPH08143931A (ja) 溶湯の精錬方法
JPH08143939A (ja) Ｆｅ−Ｎｉ系合金溶湯の精錬方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20041105

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK

17Q First examination report despatched

Effective date: 20050407

DAX Request for extension of the european patent (deleted)
RBV Designated contracting states (corrected)

Designated state(s): DE ES FR IT

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR IT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20061004

REF Corresponds to:

Ref document number: 60308860

Country of ref document: DE

Date of ref document: 20061116

Kind code of ref document: P

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2273014

Country of ref document: ES

Kind code of ref document: T3

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20070528

Year of fee payment: 5

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20070705

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20070426

Year of fee payment: 5

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20080528

Year of fee payment: 6

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20090119

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080602

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20080522

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20090415

Year of fee payment: 7

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080522

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090521

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20101201