WO2020065134A1 - Procédé d'utilisation de flux latéraux contenant un oxyde métallique dans des processus de fusion ferrochrome - Google Patents

Procédé d'utilisation de flux latéraux contenant un oxyde métallique dans des processus de fusion ferrochrome Download PDF

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Publication number
WO2020065134A1
WO2020065134A1 PCT/FI2019/050687 FI2019050687W WO2020065134A1 WO 2020065134 A1 WO2020065134 A1 WO 2020065134A1 FI 2019050687 W FI2019050687 W FI 2019050687W WO 2020065134 A1 WO2020065134 A1 WO 2020065134A1
Authority
WO
WIPO (PCT)
Prior art keywords
briquettes
ferrochrome
metal oxides
side streams
furnace
Prior art date
Application number
PCT/FI2019/050687
Other languages
English (en)
Inventor
Kimmo VALLO
Petteri LINJA
Original Assignee
Outokumpu Oyj
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 Outokumpu Oyj filed Critical Outokumpu Oyj
Priority to JP2021514333A priority Critical patent/JP7322141B2/ja
Priority to KR1020217007937A priority patent/KR102689605B1/ko
Priority to SE2150308A priority patent/SE545037C2/en
Priority to CN201980060083.4A priority patent/CN112689683A/zh
Publication of WO2020065134A1 publication Critical patent/WO2020065134A1/fr
Priority to ZA2021/01409A priority patent/ZA202101409B/en

Links

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
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/54—Processes yielding slags of special composition
    • 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
    • C21C7/068—Decarburising
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/12—Making spongy iron or liquid steel, by direct processes in electric furnaces
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B13/00—Making spongy iron or liquid steel, by direct processes
    • C21B13/12—Making spongy iron or liquid steel, by direct processes in electric furnaces
    • C21B13/125—By using plasma
    • 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
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/527—Charging of the electric furnace
    • 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
    • C21C7/0006—Adding metallic additives
    • 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
    • C21C7/0087—Treatment of slags covering the steel bath, e.g. for separating slag from the molten metal
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/242—Binding; Briquetting ; Granulating with binders
    • C22B1/243—Binding; Briquetting ; Granulating with binders inorganic
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B34/00—Obtaining refractory metals
    • C22B34/30—Obtaining chromium, molybdenum or tungsten
    • C22B34/32—Obtaining chromium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B7/00—Working 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
    • C22B7/001—Dry processes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C33/00—Making ferrous alloys
    • C22C33/04—Making ferrous alloys by melting
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B3/00—General features in the manufacture of pig-iron
    • C21B3/04—Recovery of by-products, e.g. slag
    • C21B3/06—Treatment of liquid slag
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
    • F27B3/08—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces heated electrically, with or without any other source of heat
    • Y—GENERAL 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling
    • Y—GENERAL 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies

Definitions

  • the invention relates to recycling of metal oxides by using cement based briquettes in submerged arc furnace for ferrochrome production to recover metals.
  • side streams from ferrochrome and fine steel production are formed into briquettes with cement, which briquettes can be fed into the submerged arc furnace through the standard inlet system and through the pre-heating furnace.
  • the metal oxides are reduced to metals mainly with carbon and the metals are recovered in the ferrochrome product.
  • the material(s) to be formed into briquettes is typically mixed in a concrete mixer with cement and water.
  • the mixture is used to form briquettes of the desired size in a briquetting machine and allowed to dry for a desired period to reach the required strength.
  • the production method here is the same used to produce cement-based slab stones.
  • Metal oxides from ferrochrome production that can be reduced in the submerged arc furnace under selected conditions can be used to form briquettes.
  • suitable fractions are, for example, dust from filter plants, flakes from casting and rolling machines, slurries from water treatment, shot blasting dust from cold rollers and metal sediment formed by acid treatment in annealing - pickling processes.
  • suitable fractions are, for example, fine materials formed in pelleting and furnace feeding.
  • a suitable reduction material such as carbon, can be added into the briquettes to speed up the reaction kinetics.
  • the potential of the invention in ferrochrome production is in improving chromium yield, reducing waste, better use of raw material and avoiding landfill charges.
  • the composition of the briquette can be altered to suit the customer.
  • advantages would be in improving the present recycling of the side streams and in making recycling cheaper.
  • US patent US8409320 B2 discloses briquetting steel production side streams containing oxides with molasses and feeding these into the arc furnace of a smelting plant, where metals are reduced and slag is boiled.
  • the patent does not deal with briquetting oxide material with cement and feeding the briquettes into the submerged arc furnace for ferrochrome production or into the arc furnaces for steel production.
  • US patent publications US2014/0352496 and US 2013192422 disclose preparation and use of cement and molasses based briquettes in arc furnaces for fine steel production.
  • the patent concentrates on slag boiling with briquettes in an arc furnace.
  • the patent does not deal with using briquettes in a submerged arc furnace used in ferrochrome production.
  • the solution according to the present invention is based on feeding into the ferrochrome furnace material from side streams of ferrochrome and fine steel production that would be difficult to use with any other technology. Additionally, it is possible, and rational to feed other side streams from the metal industry and the mining industry containing metal oxides that can be reduced with carbon into the ferrochrome arc furnace.
  • a mixture is formed with cement and water.
  • blast furnace slag for example can be used as desired.
  • the mixture is cast as briquettes, for example, as a 6 pointed 60 x 60 x 60 mm sized briquette.
  • a finished briquette contains 2 - 30% cement, of which a part (10 - 70%) can be replaced with for example blast furnace slag.
  • the size of the briquette depends on or is influenced by the feeding or inlet system in the used submerged arc furnace. Briquettes are allowed to dry for about 4 weeks in outdoor conditions to reach the final strength before feeding into the furnace. It is also possible to use accelerators and heating to adjust hardness.
  • reducing agent coke, ferrosilicon, aluminium, silicon carbide
  • Briquettes are preferably fed into the submerged arc furnace via a preheating furnace in which the briquette dries and heats up to approximately 500 °C in a C0 2 atmosphere. This breaks silicate bonds and replaces them with carbonate bonds, while the briquette maintains it strength.
  • the briquette flows as plug flow through an inlet tube into the pot of the submerged arc furnace and simultaneously starts to heat because of the furnace gases.
  • the metal oxides within start reducing first the iron oxide reduces partly by pot gases, and finally chrome oxide reduces.
  • the cement contained in the briquettes increases the pH of slag and thus reduces the chromium content of slag by approximately 0.5 - 5%.
  • Reduced metals melt and dissolve into metal in the furnace and the melt is melted out of the furnace as a castable alloy, the composition of which depends on the metal content of the feeds. In practice, for example all Ni, Mo and Fe fractions in feeds are reduced into metal.
  • Table 2 The composition of metal and slag is presented in Table 2.
  • various secondary raw-materials such as catalysts are used as a briquette raw-material, allowing metals in metal oxides to be recovered into the ferrochrome.
  • These raw-materials can be metal oxides that contain nickel, molybdenium, titanium, copper, manganese, or cobolt.
  • Figure 1 shows an Ellingham diagram, which illustrates the order of reduction of metal oxides.
  • Figure 2 shows how the levels of nickel and manganese change in the ferrochrome product during the feed experiment.
  • Figure 3 shows changes in chromium content of the ferrochrome product during the experiment.
  • Figure 4 shows carbon and silicon content of the ferrochrome product during the experiment.
  • the order of reduction of metal oxides is defined by the Ellingham diagram of Figure 1. Different metals that can be reduced by carbon in the arc furnace under selected conditions can be seen. Carbon is able to reduce metals that are above the line presenting the reaction of carbon. This reduction reaction itself is dependent on temperature and pressure. In practice, noble elements reduce first, so the reduction order is Ni, Mo, Fe, Cr.
  • the diagram also shows reaction equations for reduction, varying according to oxidation stage, for example, individual equations for different oxidation stages of iron.
  • cement is the only binding material that can hold the briquette together in the pre-heating furnace temperature of 400-600 degrees. Additionally, it gives the briquette adequate mechanical strength so that briquettes can be fed into the furnace through the inlet system. Chemical bonds of the cement change to carbonate bonds in the heat of pre-heating oven, whereby the original strength of the briquette is almost completely maintained.
  • cement-based briquettes also provides the submerged arc furnace with lime that increases the pH of the slag leading to a higher degree of reduction and a higher yield of chromium.
  • the particle size distribution in briquettes depends on the raw materials used in the formation of briquettes.
  • the particle size distribution should follow the Fuller curve as closely as possible because this allows minimising the amount of cement used and provides savings in raw materials.
  • the amount of briquettes added can be up to 20 w-%, preferably 3-10 w-% of the total material feed dependent on the current obtained slag material analysis
  • the invention is not limited to the raw materials presented above.
  • other side streams containing metal oxides can also be used economically.
  • oxides from the nickel industry would blend nickel into ferrochrome and the thus formed ferrochrome would be better suited for the manufacture of austenitic steel grades.
  • Figures 2-4 show results of an experiment in which cement-based briquettes containing flakes from fine steel production were fed into a submerged arc furnace used in ferrochrome production.
  • Figure 2 shows changes in nickel and manganese content of the ferrochrome product during the feed experiment, i.e. metal oxides reduce to end-product.
  • Figure 3 shows change in chromium concentration of the ferrochrome product in the end-product during the experiment.
  • the chromium concentration dropped as expected as the proportion of other metals increased.
  • Figure 4 shows that carbon and silicon concentrations remain at a normal level in the end product during the briquette experiment.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Analytical Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Compounds Of Iron (AREA)

Abstract

L'invention concerne le briquetage de poussières d'oxyde métallique et de matériau fin avec des liants à base de ciment. Les briquettes peuvent ensuite être introduites dans des fours à arc pour la production de ferrochrome à travers des systèmes d'entrée déjà existants.
PCT/FI2019/050687 2018-09-26 2019-09-25 Procédé d'utilisation de flux latéraux contenant un oxyde métallique dans des processus de fusion ferrochrome WO2020065134A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
JP2021514333A JP7322141B2 (ja) 2018-09-26 2019-09-25 フェロクロム製錬プロセスにおいて、金属酸化物を含有する側流を利用するための方法
KR1020217007937A KR102689605B1 (ko) 2018-09-26 2019-09-25 페로크롬 제련 공정에서 금속 산화물 함유 사이드 스트림을 활용하는 방법
SE2150308A SE545037C2 (en) 2018-09-26 2019-09-25 A method for utilizing metal oxide containing side streams in ferrochrome smelting processes
CN201980060083.4A CN112689683A (zh) 2018-09-26 2019-09-25 在铬铁熔炼过程中利用含金属氧化物的侧流的方法
ZA2021/01409A ZA202101409B (en) 2018-09-26 2021-03-01 A method for utilizing metal oxide containing side streams in ferrochrome smelting processes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI20185805A FI130393B (fi) 2018-09-26 2018-09-26 Menetelmä metallioksideja sisältävien sivuvirtojen hyödyntämiseksi ferrokromin sulatusprosesseissa
FI20185805 2018-09-26

Publications (1)

Publication Number Publication Date
WO2020065134A1 true WO2020065134A1 (fr) 2020-04-02

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PCT/FI2019/050687 WO2020065134A1 (fr) 2018-09-26 2019-09-25 Procédé d'utilisation de flux latéraux contenant un oxyde métallique dans des processus de fusion ferrochrome

Country Status (8)

Country Link
JP (1) JP7322141B2 (fr)
KR (1) KR102689605B1 (fr)
CN (1) CN112689683A (fr)
FI (1) FI130393B (fr)
SE (1) SE545037C2 (fr)
TW (1) TWI820222B (fr)
WO (1) WO2020065134A1 (fr)
ZA (1) ZA202101409B (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50130615A (fr) * 1974-04-02 1975-10-16
US3947267A (en) * 1973-07-23 1976-03-30 Armco Steel Corporation Process for making stainless steel
US5654976A (en) * 1995-04-18 1997-08-05 Elkem Technology A/S Method for melting ferrous scrap metal and chromite in a submerged arc furnace to produce a chromium containing iron
WO2010103343A1 (fr) * 2009-03-10 2010-09-16 Tata Steel (Kzn) (Pty) Limited Procédé amélioré pour produire du ferrochrome à haute teneur en carbone (hfecr) et charger du chrome en utilisant un nouveau type d'agglomérats de minerai de chromite
KR20120075332A (ko) * 2010-12-28 2012-07-06 주식회사 포스코 스테인리스 제강용 용융 환원제 및 이를 이용한 용융 환원법

Family Cites Families (8)

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Publication number Priority date Publication date Assignee Title
JPS5288520A (en) * 1976-01-21 1977-07-25 Nisshin Steel Co Ltd Treatment of waste generated in manufacturing alloy steel
JPS531103A (en) * 1976-06-25 1978-01-07 Nisshin Steel Co Ltd Treatment of plating sludge
JPS5848642A (ja) * 1981-09-18 1983-03-22 Nippon Kokan Kk <Nkk> 非焼成塊成鉱の製造法
JPH0660359B2 (ja) * 1985-01-14 1994-08-10 新日本製鐵株式会社 非焼成塊成鉱の製造方法
CN1158903A (zh) * 1996-12-03 1997-09-10 吕美竺 一种直接炼钢和炼铁用冷固球团的工业生产方法
US7896963B2 (en) 2003-09-23 2011-03-01 Hanqing Liu Self-reducing, cold-bonded pellets
CN103436694A (zh) * 2013-09-04 2013-12-11 宁夏天元锰业有限公司 一种制备粉铬矿球团的方法
CN104962763B (zh) * 2015-05-25 2016-11-30 北京科技大学 一种用晶体硅切割废料生产铬系铁合金的方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3947267A (en) * 1973-07-23 1976-03-30 Armco Steel Corporation Process for making stainless steel
JPS50130615A (fr) * 1974-04-02 1975-10-16
US5654976A (en) * 1995-04-18 1997-08-05 Elkem Technology A/S Method for melting ferrous scrap metal and chromite in a submerged arc furnace to produce a chromium containing iron
WO2010103343A1 (fr) * 2009-03-10 2010-09-16 Tata Steel (Kzn) (Pty) Limited Procédé amélioré pour produire du ferrochrome à haute teneur en carbone (hfecr) et charger du chrome en utilisant un nouveau type d'agglomérats de minerai de chromite
KR20120075332A (ko) * 2010-12-28 2012-07-06 주식회사 포스코 스테인리스 제강용 용융 환원제 및 이를 이용한 용융 환원법

Also Published As

Publication number Publication date
TWI820222B (zh) 2023-11-01
FI130393B (fi) 2023-08-09
CN112689683A (zh) 2021-04-20
SE2150308A1 (en) 2021-03-18
JP7322141B2 (ja) 2023-08-07
ZA202101409B (en) 2023-10-25
KR102689605B1 (ko) 2024-07-30
FI20185805A1 (fi) 2020-03-27
SE545037C2 (en) 2023-03-07
KR20210065943A (ko) 2021-06-04
JP2022501497A (ja) 2022-01-06
TW202024343A (zh) 2020-07-01

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