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US20110000340A1 - Method for removing copper in steel scraps - Google Patents

Method for removing copper in steel scraps Download PDF

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Publication number
US20110000340A1
US20110000340A1 US12/920,741 US92074109A US2011000340A1 US 20110000340 A1 US20110000340 A1 US 20110000340A1 US 92074109 A US92074109 A US 92074109A US 2011000340 A1 US2011000340 A1 US 2011000340A1
Authority
US
United States
Prior art keywords
hot metal
copper
sulfur
flux
mass
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.)
Abandoned
Application number
US12/920,741
Other languages
English (en)
Inventor
Akitoshi Matsui
Yuichi Uchida
Yasuo Kishimoto
Futoshi Ogasawara
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.)
JFE Steel Corp
Original Assignee
JFE Steel Corp
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=41056175&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US20110000340(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by JFE Steel Corp filed Critical JFE Steel Corp
Assigned to JFE STEEL CORPORATION reassignment JFE STEEL CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: OGASAWARA, FUTOSHI, UCHIDA, YUICHI, KISHIMOTO, YASUO, MATSUI, AKITOSHI
Publication of US20110000340A1 publication Critical patent/US20110000340A1/en
Abandoned legal-status Critical Current

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Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/10General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents
    • C22B9/106General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents the refining being obtained by intimately mixing the molten metal with a molten salt or slag
    • 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
    • C21C1/04Removing impurities other than carbon, phosphorus or sulfur
    • 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
    • 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
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B15/00Obtaining copper
    • C22B15/0026Pyrometallurgy
    • C22B15/0056Scrap treating
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B7/00Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/10General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals with refining or fluxing agents; Use of materials therefor, e.g. slagging or scorifying agents
    • 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
    • C21C2200/00Recycling of waste material
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00Preliminary treatment of ores or scrap
    • C22B1/005Preliminary treatment of scrap
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

Definitions

  • the patent document 1 does not disclose desulfurization of the high carbon molten iron after removal of copper at all.
  • the copper removal treatment is carried out by agitation of the slag and molten iron by injecting Ar gas from the bottom of a refining vessel (hot-metal transfer ladle).
  • a refining vessel hot-metal transfer ladle
  • the agitation of slag is not enough and the facilities are complicated as the gas blown-in tuyere needs to be provided at the bottom of the hot-metal transfer ladle.
  • an electric heater is provided for holding the reaction temperature at 1200 to 1500 ° C., and a refining vessel with a cover is used to prevent contact with the air, however, such facilities become large.
  • the present invention was carried out in view of the foregoing, and has an object to provide a method for removing copper in copper-containing steel scraps efficiently and without large facilities when producing high-quality steel with use of the steel scraps as an iron source.
  • a method for removing copper in steel scraps according to a fourth invention is characterized in that, in any one of the first to third inventions, the hot metal before copper removal by the sulfur-containing flux has a temperature of 1200° C. or higher and 1500° C. or lower, and contains carbon at a concentration of 2% by mass or more and copper at a concentration of 0.1% or more by mass and 1.0% by mass or less.
  • a method for removing copper in steel scraps according to a sixth invention is characterized in that, in any one of the first to fifth inventions, the hot metal before copper removal by the sulfur-containing flux contains sulfur at a concentration of 0.01% by mass or more.
  • a method for removing copper in steel scraps according to a seventh invention is characterized in that, in any one of the first to sixth inventions, removing of the copper contained in the hot metal is carried out by refining equipment with mechanical stirrer.
  • the sulfur-containing flux may be at least partially added by injection (injection adding).
  • injection adding at least a part of a starting material of the sulfur-containing flux (for example, soda ash and ferrosulfur) may be injected with a carrier gas into the hot metal in the refining vessel.
  • a starting material that does not contain sulfur for example, soda ash
  • a starting material that contains sulfur for example, ferrosulfur
  • a method for removing copper in steel scraps according to a ninth invention is characterized in that, in any one of the first to eighth inventions, melting of the copper-containing steel scraps with addition of the carbon is conducted by using a shaft furnace having a coke bed formed inside.
  • the weight ratio thereof is preferably 1:0.4 to 1:4, and mole fraction of S may be determined such that the mole fraction of estimated generated Na 2 S is about 0.2 or more.
  • copper removal with use of the sulfur-containing flux is confirmed in principle, however, as it is a process of low partition ratio (ratio of Cu concentration in the flux to Cu concentration in the hot metal) , it is effective for expediting copper removal to expedite material transfer at the slag part formed in the refining vessel by adding the sulfur-containing flux. For this purpose, it is effective to stir also the slag layer.
  • the copper removal treatment is carried out at the hot metal stage, however, the temperature range of the hot metal (1200 to 1400 ° C.) is lower than the temperature range of molten steel (1550 to 1700 ° C.), the slag fluidity is low, and therefore, the copper removal can be expedited more effectively by stirring of the slag.
  • the concentration of carbon prior to the copper removal treatment is preferably 2% by mass or more.
  • the concentration of carbon prior to the copper removal treatment is less than 2% by mass, the liquidus temperature of the hot metal increases and there may be a problem such as adhesion of the hot metal to the vessel wall. Here, there is no problem if the concentration of the carbon contained is increased to the saturated concentration.
  • the concentration of copper in the hot metal prior to the copper removal treatment preferably is 0.1% or more by mass, and 1.0% by mass or less. If the concentration of copper in the hot metal prior to the copper removal treatment exceeds 1.0% by mass, the amount of sulfur-containing flux required for removal of copper becomes excessively large and practically, the burden is heavy. On the other hand, if the concentration is less than 0.1% by mass, it can be applied to high-quality steel without performing the copper removal treatment, for example, by dilution with hot metal containing a small amount of copper.
  • any composition basically for steel purposes may be selected without problem.
  • the concentration of silicon is 0.5% by mass or less, and the concentration of manganese is 0.5% by mass or less. If they exceed these values, silicon oxide and manganese oxide resultant from oxidation of these components in the copper removal treatment transfer into slag, and the amount of slag is increased and the burden of slag treatment is increased. Besides, the efficiency of copper removal reaction of the sulfur-containing flux can be improved more by preventing too much existence of silicon oxide and manganese oxide.
  • the shaft furnace with the coke bed formed inside is a device for charging carbon containing steel scraps and coke and, if necessary, fluxes from an upper part of the shaft furnace, blowing air, oxygen-enriched air, oxygen gas or the like via a tuyere provided at a lower part of the shaft furnace, preferably as hot gas to burn the coke, melting the fluxes and copper containing steel scraps inside the furnace by combustion heat of the coke and bringing the hot metal and liquid slag out of the outlet at the furnace bottom.
  • a desulfurization agent having CaO as the main component a desulfurization agent having calcium carbide as the main component, a desulfurization agent having soda ash as the main component, metal Mg or the like may be used.
  • the copper removal treatment was carried out in the following three methods, that is, after charging about 5 tons of hot metal for steelmaking in a ladle-shaped refining vessel, a method of adding flux having FeS-Na 2 S (mole fraction of Na 2 S in the flux: 0.4) as the main component onto the hot metal in refining equipment with mechanical stirrer, immersing, in the hot metal, impeller covered with a refractory material and rotating the impeller to stir the hot metal and flux (test No. 1) , a method of injecting stirring gas from an injection lance immersed in the hot metal inside the refining vessel to stir the hot metal while adding flux having FeS-Na 2 S as the main component (test No.
  • the concentration of copper in the hot metal after the treatment/the concentration of copper in the hot metal before the treatment was 0.4 or more, and these proved that the copper removal was carried out well.
  • the temperature of the hot metal for steelmaking produced in the shaft furnace was 1400° C.
  • the concentration of carbon was 4.0% by mass
  • the concentration of copper was 0.30% by mass
  • the concentration of sulfur was 0.11% by mass.
  • the copper removal treatment was conducted by charging about 60 tons of hot metal for steelmaking in a ladle-shaped refining vessel, adding 50 kg of iron-sulfur alloy (the concentration of sulfur in the alloy: 48% by mass) and 35 kg of soda ash per ton of the hot metal onto the hot metal in refining equipment with mechanical stirrer, immersing impeller covered with a refractory material in the hot metal and rotating the impeller to stir the hot metal and flux.
  • the concentration of copper in the hot metal after the copper removal treatment was 0.14% by mass and the concentration of sulfur was 0.44% by mass.
  • the refining flux for copper removal used was iron-sulfur alloy (ferrosulfur, the percentage of sulfur content: 48% by mass) and soda ash (Na 2 CO 3 ).
  • Table 4 shows a list of test conditions and test results. Components of the hot metal before the copper removal treatment other than those listed in Table 4 were prepared to have 4.5 to 4.7% by mass of carbon, 0.20% by mass of silicon, 0.15% by mass of manganese and 0.050% by mass of phosphorus.
  • the temperature of the hot metal was 1400° C.
  • the nitrogen gas was only blown via the injection lance and refining flux for copper removal was added from a refining agent supplying hopper above the ladle.
  • the copper removal ratio was 40%, which was lower than that of the mechanical stirring and injection cases.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US12/920,741 2008-03-05 2009-03-03 Method for removing copper in steel scraps Abandoned US20110000340A1 (en)

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
JP2008-054635 2008-03-05
JP2008054635 2008-03-05
JP2008284935 2008-11-06
JP2008-284935 2008-11-06
JP2009-006297 2009-01-15
JP2009006297A JP5402005B2 (ja) 2008-03-05 2009-01-15 鋼屑中の銅の除去方法
PCT/JP2009/054370 WO2009110627A1 (fr) 2008-03-05 2009-03-03 Procédé d'élimination de cuivre contenu dans des déchets d'acier

Publications (1)

Publication Number Publication Date
US20110000340A1 true US20110000340A1 (en) 2011-01-06

Family

ID=41056175

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/920,741 Abandoned US20110000340A1 (en) 2008-03-05 2009-03-03 Method for removing copper in steel scraps

Country Status (10)

Country Link
US (1) US20110000340A1 (fr)
EP (1) EP2248916B1 (fr)
JP (1) JP5402005B2 (fr)
KR (2) KR20130045955A (fr)
CN (1) CN101960023B (fr)
BR (1) BRPI0909687A2 (fr)
CA (1) CA2715322C (fr)
MX (1) MX2010009609A (fr)
TW (1) TWI409338B (fr)
WO (1) WO2009110627A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022164878A1 (fr) * 2021-01-26 2022-08-04 Nucor Corporation Procédé et système de réduction de la teneur en métal non ferreux de ferrailles d'acier

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5625654B2 (ja) * 2009-09-15 2014-11-19 Jfeスチール株式会社 溶銑の製造方法
JP5581760B2 (ja) * 2010-03-19 2014-09-03 Jfeスチール株式会社 鋼屑中の銅の除去方法及び鋼屑を鉄源とした溶鋼の製造方法
JP5581759B2 (ja) * 2010-03-19 2014-09-03 Jfeスチール株式会社 鋼屑中の銅の除去方法
KR101321086B1 (ko) * 2010-12-22 2013-10-23 주식회사 포스코 용선 정련 방법
JP5724861B2 (ja) * 2011-12-09 2015-05-27 新日鐵住金株式会社 鉄スクラップからの銅の硫化除去方法
JP6065538B2 (ja) * 2012-11-20 2017-01-25 Jfeスチール株式会社 溶銑の脱銅処理方法
KR101462168B1 (ko) * 2012-12-26 2014-11-14 주식회사 포스코 용철 처리장치 및 그 처리방법
CN107130082B (zh) * 2017-04-26 2019-05-07 湖南工业大学 一种高铜铁料中铜元素有效分离的方法
CN107151736A (zh) * 2017-06-21 2017-09-12 江苏省冶金设计院有限公司 一种制备脱铜铁水的系统及方法
CN110793880A (zh) * 2019-09-30 2020-02-14 鞍钢股份有限公司 一种冶金还原矿料过程模拟装置及方法
CN110565120B (zh) * 2019-10-18 2021-09-07 东北大学 一种在含铜铁液中脱除并回收铜的方法
CN115369258A (zh) * 2022-08-04 2022-11-22 江苏鑫瑞崚新材料科技有限公司 一种低银低硫超高纯铜提纯真空熔炼工艺
CN116287549B (zh) * 2023-03-21 2024-07-02 武汉科技大学 真空处理低碳低硫钢同时脱除残留元素锡和锑的方法
CN117144079B (zh) * 2023-07-20 2025-12-16 东北大学 一种含铜铁水硫化分离的方法及装置

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* Cited by examiner, † Cited by third party
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US2403419A (en) * 1943-04-15 1946-07-02 Revere Copper & Brass Inc Method of recovering the constituents of scrap bi-metal
US2512578A (en) * 1949-05-26 1950-06-20 Jordan James Fernando Method of desulfurizing and decopperizing ferrous metal
US4925488A (en) * 1987-07-30 1990-05-15 Milton Blander Removal of copper from ferrous scrap
JPH04198431A (ja) * 1990-11-29 1992-07-17 Nippon Steel Corp 鋼鉄中の銅の除去方法
JPH07316618A (ja) * 1994-05-17 1995-12-05 Nkk Corp 溶融還元溶銑の予備精錬方法
JP2007002305A (ja) * 2005-06-24 2007-01-11 Nippon Chutetsukan Kk キュポラによる溶銑の溶製方法

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SU1227689A1 (ru) * 1984-07-03 1986-04-30 Магнитогорский горно-металлургический институт им.Г.И.Носова Способ удалени меди из расплава чугуна
JPS61119612A (ja) * 1984-11-14 1986-06-06 Sumitomo Metal Ind Ltd 溶鉄の脱銅及び/又は脱錫方法
JPS61266515A (ja) * 1985-05-21 1986-11-26 Masanori Tokuda 含銅溶鉄より低銅鋼を製造する方法
JPS63192812A (ja) * 1987-02-05 1988-08-10 Sumitomo Metal Ind Ltd 溶銑の脱Cu方法
JPH09143586A (ja) * 1995-11-28 1997-06-03 Ryokichi Shinpo 溶鉄中の銅の除去方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2403419A (en) * 1943-04-15 1946-07-02 Revere Copper & Brass Inc Method of recovering the constituents of scrap bi-metal
US2512578A (en) * 1949-05-26 1950-06-20 Jordan James Fernando Method of desulfurizing and decopperizing ferrous metal
US4925488A (en) * 1987-07-30 1990-05-15 Milton Blander Removal of copper from ferrous scrap
JPH04198431A (ja) * 1990-11-29 1992-07-17 Nippon Steel Corp 鋼鉄中の銅の除去方法
JPH07316618A (ja) * 1994-05-17 1995-12-05 Nkk Corp 溶融還元溶銑の予備精錬方法
JP2007002305A (ja) * 2005-06-24 2007-01-11 Nippon Chutetsukan Kk キュポラによる溶銑の溶製方法

Non-Patent Citations (1)

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Title
Shirakawa et al., Yoyu Flux ni yoru Yosen no Datsudo, 1986, Journal of the Iron & Steel Institute, vol. 72, no. 12, pp 169 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022164878A1 (fr) * 2021-01-26 2022-08-04 Nucor Corporation Procédé et système de réduction de la teneur en métal non ferreux de ferrailles d'acier
US11834728B2 (en) 2021-01-26 2023-12-05 Nucor Corporation Method and system of reducing non-ferrous metal content of scrap steel

Also Published As

Publication number Publication date
CN101960023B (zh) 2014-06-18
JP2010133002A (ja) 2010-06-17
JP5402005B2 (ja) 2014-01-29
EP2248916B1 (fr) 2013-10-30
EP2248916A4 (fr) 2011-01-05
MX2010009609A (es) 2010-09-30
CN101960023A (zh) 2011-01-26
EP2248916A1 (fr) 2010-11-10
TWI409338B (zh) 2013-09-21
KR20130045955A (ko) 2013-05-06
KR20100105794A (ko) 2010-09-29
KR101276921B1 (ko) 2013-06-19
BRPI0909687A2 (pt) 2015-09-22
CA2715322C (fr) 2013-01-15
WO2009110627A1 (fr) 2009-09-11
CA2715322A1 (fr) 2009-09-11
TW200944594A (en) 2009-11-01

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