US20150050200A1 - Production method for hematite for iron production - Google Patents

Production method for hematite for iron production Download PDF

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Publication number
US20150050200A1
US20150050200A1 US14/386,222 US201314386222A US2015050200A1 US 20150050200 A1 US20150050200 A1 US 20150050200A1 US 201314386222 A US201314386222 A US 201314386222A US 2015050200 A1 US2015050200 A1 US 2015050200A1
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United States
Prior art keywords
nickel
sulfur
leach
hematite
iron
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Abandoned
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US14/386,222
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English (en)
Inventor
Hideki Sasaki
Hiroyuki Mitsui
Yasumasa Kan
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Sumitomo Metal Mining Co Ltd
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Sumitomo Metal Mining Co Ltd
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Assigned to SUMITOMO METAL MINING CO., LTD. reassignment SUMITOMO METAL MINING CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MITSUI, HIROYUKI, SASAKI, HIDEKI
Publication of US20150050200A1 publication Critical patent/US20150050200A1/en
Abandoned legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G49/00—Compounds of iron
    • C01G49/02—Oxides; Hydroxides
    • C01G49/06—Ferric oxide [Fe2O3]
    • 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
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
    • C22B3/22—Treatment or purification of solutions, e.g. obtained by leaching by physical processes, e.g. by filtration, by magnetic means, or by thermal decomposition
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B17/00—Sulfur; Compounds thereof
    • C01B17/48—Sulfur dioxide; Sulfurous acid
    • C01B17/50—Preparation of sulfur dioxide
    • C01B17/501—Preparation of sulfur dioxide by reduction of sulfur compounds
    • C01B17/507—Preparation of sulfur dioxide by reduction of sulfur compounds of iron sulfates
    • 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
    • C22B23/00—Obtaining nickel or cobalt
    • C22B23/04—Obtaining nickel or cobalt by wet processes
    • C22B23/0453—Treatment or purification of solutions, e.g. obtained by leaching
    • C22B23/0461—Treatment or purification of solutions, e.g. obtained by leaching by chemical methods
    • 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
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/80—Compositional purity
    • 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

Definitions

  • the present invention relates to a production method for refining a leach residue obtained by hydrometallurgical refining of nickel oxide ore into hematite that can be used as an iron-making raw material and has low-grade sulfur.
  • the iron oxide that is a raw material of the steel is a limited resource, and furthermore it is gradually hard to obtain high-quality iron ore required to maintain a quality of steel.
  • nickel oxide ore such as limonite or saprolite is put into a pressure device such as an autoclave along with a sulfuric acid, and nickel is leached under high pressure and high temperature of about 240 to 260° C.
  • the nickel leached into a solution of the sulfuric acid is used as nickel metal or a nickel salt compound by adding a neutralizer to neutralize a surplus acid, separating a leach residue by solid-liquid separation, separating impurities to recover the leach residue as an intermediate raw material in the form of hydroxide or sulfide, and further refining the intermediate raw material.
  • HPAL high pressure acid leach
  • nickel can be almost completely leached even from low-grade ore in which valuable metals intended for recovery are contained by not more than 1% to 2% by weight (hereinafter indicated by “%” with regard to a grade).
  • the HPAL process has a feature of concentrating the valuable metals up to the same grade as a conventional raw material by producing an intermediate raw material from a leachate, and refining the nickel in a process similar to a conventional process.
  • HPAL process may be applied to various types of ores such as nickel sulfide ore, copper sulfide ore, and copper oxide ore, in addition to the nickel oxide ore.
  • a main component of the leach residue obtained by the HPAL process is iron oxide having the form of hematite. This is secondarily obtained because each of oxide ore and sulfide ore of nickel or copper used as a raw material contains iron of an amount far more than a content of nickel or copper.
  • leach residues are created at a high temperature, and thus have the form of oxide that is chemically or environmentally stable.
  • the leach residues have no special utility value, and have been scrapped to a residue disposal yard. For this reason, it has been a grave challenge how to secure the disposal yards for an enormous amount of leach residues generated along with the smelting.
  • the leach residue of the HPAL process cannot be directly used for the aforementioned iron-making raw material.
  • the reason is that the leach residue of the HPAL process contains gangue and impurities, particularly sulfur, in addition to the iron oxide and requires exhaust gas treatment, and thus is not suitable for the raw material used in the conventional iron-making process in common.
  • a grade of sulfur in iron oxide usable for the iron-making raw material differs depending on facility capacity and an amount of production of individual ironworks, and generally needs to be suppressed to less than 1%.
  • the sulfur is hardly contained in the original nickel oxide ore. Nevertheless, the sulfur contained in the leach residue by about 1 to 3% results from calcium sulfate (plaster) generated by reaction of sulfuric acid and limestone or slaked lime added as the neutralizer in order to neutralize free sulfuric acid remaining at the leach slurry.
  • calcium sulfate plaster
  • the neutralizer suitable for such application includes sodium hydroxide, potassium hydroxide, magnesium hydroxide, and magnesium oxide.
  • JP H03-176081 A discloses a method that includes stirring a jarosite-containing residual and a zinc sulfide inclusion in an autoclave at least under oxygen partial pressure of 1000 kPa at a temperature of 130 to 170° C. along with a free sulfuric acid of 40 to 100 g/l, substantially dissolving iron and zinc fractions of a concentrate containing the residual and zinc sulfide, introducing the solution into a leach circulation passage for zinc electrolysis to settle iron in the form of hematite, and separating sulfur from the above solid, and supplying the residual for separate application.
  • the invention is intended to provide a production method for refining hematite, which has such a low sulfur component as to be used as an iron-making raw material, from a leach residue containing iron oxide produced by a high pressure acid leach (HPAL) process.
  • HPAL high pressure acid leach
  • a first aspect of the present invention provides a method for producing (high purity) hematite for ironmaking by a process of adding an oxidant and sulfuric acid to nickel oxide ore and then leaching nickel.
  • the method further includes heating a leach residue, which is obtained after the nickel is leached, to 600° C. or more.
  • a second aspect of the present invention provides a method for producing (high purity) hematite for ironmaking by a process of adding an oxidant and sulfuric acid to nickel oxide ore and then leaching nickel.
  • the method further includes heating a leach residue, which is obtained after the nickel is leached, to 800° C. or more and 1400° C. or less.
  • the present invention can bring about several industrially significant effects.
  • wastes such as a leach residue, discharged in a refining process can be applied to the iron-making raw materials, and it is thus possible to remarkably reduce an amount of the scrapped leach residue and further reduce production costs by lowering an environmental risk, reducing scrapping costs, and reducing construction costs of a leach residue disposal yard;
  • FIG. 1 is a flow chart showing a recovery process of performing high-pressure sulfuric acid leach on a mineral containing valuable metals and iron to recover the valuable metals, and further showing a refining process of hematite having low-grade sulfur which is associated with the recovery process;
  • FIG. 2 is a diagram illustrating a relation between a heating temperature and a grade of sulfur in a leach residue.
  • the present invention is to heat a leach residue obtained when a mineral, such as nickel oxide ore, containing valuable metals and iron is subjected to high-pressure sulfuric acid leach, to separate sulfur, and to produce high-purity hematite that can be used as an iron-making raw material having a low sulfur content.
  • FIG. 1 illustrates a flow for a recovery process of performing high-pressure sulfuric acid leach on a mineral, such as nickel oxide ore, containing valuable metals and iron to recover the valuable metals and a further flow for a refining process of a production method according to the present invention of producing hematite having low-grade sulfur from a leach residue obtained in association with the recovery process.
  • a mineral such as nickel oxide ore
  • the flow for the recovery process of the valuable metals is indicated by an outline arrow, and the flow for the refining process of the hematite according to the invention is indicated by a black arrow.
  • a leach residue to be a starting raw material of the present process is obtained as sediment when a leach slurry, which is generated by neutralizing a leachate obtained in the event of high-pressure sulfuric acid leach as illustrated in FIG. 1 , is subjected to solid-liquid separation.
  • the leach residue is formed in a state in which a reaction product of a neutralizer input in the neutralization process and a surplus acid is contained. Accordingly, limestone or slaked lime added as the neutralizer and sulfuric acid are reacted to neutralize a free sulfuric acid remaining in the leach slurry.
  • the leach residue contains sulfur resulting from created calcium sulfate (plaster) by several percentage (%).
  • the leach residue is heated on given conditions. That is, as illustrated in FIG. 1 , the iron oxide (hematite) for ironmaking which has low-grade sulfur is refined by roasting the leach residue and evaporating the sulfur component.
  • FIG. 2 illustrates a relation between a heating temperature and the sulfur grade in the leach residue.
  • a temperature at which the leach residue is heated is 600° C. or more, preferably 800° C. or more, which is an effective temperature in order to make the sulfur grade in the leach residue less than 1%. Further, when the heating temperature exceeds 800° C., the sulfur grade is sharply reduced, which is more preferable. When the heating temperature becomes 1300° C., the sulfur grade can be reduced up to 0.1% or less, which is more preferable, but when the heating temperature more preferably exceeds 1400° C., this gives no great difference, and is not very preferable in the aspect of facility investment such as an increase in heating energy or a need for heat resistance of a furnace wall material. Accordingly, the heating temperature is 600° C. or more and 1400° C. or less, and preferably 800° C. or more and 1300° C. or less.
  • a heating time is affected by a furnace size and an amount of the residue, and thus may be adequately adjusted. Further, the heating is performed in an oxidizing atmosphere such as atmospheric air. Thereby, along with the heating, the sulfur is removed from the leach residue as sulfur dioxide, and the high-purity iron oxide (hematite) is formed.
  • an oxidizing atmosphere such as atmospheric air.
  • Nickel oxide ore having 1% nickel grade and 46 to 48% iron grade was adjusted to be a slurry of 30 to 40% by weight, and then was mixed with sulfuric acid of 64% by weight. Subsequently, the slurry was charged into a pressure device, heated to 240 to 250° C., and maintained for one hour, and a leachate was obtained by leaching nickel in the ore (HPAL).
  • the leachate was cooled to about 70° C., and then slaked lime was added to neutralize a surplus acid (neutralization).
  • the slurry containing a leach residue after the surplus acid was neutralized (hereinafter the leach residue after the neutralization is referred to as “neutralized residue’) was subjected to solid-liquid separation using Nutsche and a filtering bottle, and was separated into the leachate and the neutralized residue (solid-liquid separation).
  • the neutralized residue was equally divided into six parts, which were respectively raised to 30° C., 200° C., 800° C., 1000° C., 1200° C., and 1400° C., heated for one hour, and cooled.
  • the sulfur grade is reduced up to about 1% at about 600° C., and that, when the temperature exceeds 800° C., the sulfur grade is sharply reduced, and the sulfur can be effectively separated.
  • Table 1 results of measuring the iron and sulfur grades in the neutralized residue after the heating are illustrated.
  • the iron and sulfur grades were measured by fluorescent X-ray analysis.
  • FIG. 1 A first figure.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geochemistry & Mineralogy (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Compounds Of Iron (AREA)
US14/386,222 2012-03-19 2013-01-16 Production method for hematite for iron production Abandoned US20150050200A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2012062794A JP5424139B2 (ja) 2012-03-19 2012-03-19 製鉄用ヘマタイトの製造方法
JP2012-062794 2012-03-19
PCT/JP2013/050671 WO2013140837A1 (ja) 2012-03-19 2013-01-16 製鉄用ヘマタイトの製造方法

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US (1) US20150050200A1 (zh)
EP (1) EP2829516B1 (zh)
JP (1) JP5424139B2 (zh)
CN (1) CN104203830B (zh)
AU (1) AU2013236727B2 (zh)
CA (1) CA2867672C (zh)
PH (1) PH12014502100B1 (zh)
WO (1) WO2013140837A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10125025B2 (en) 2014-02-27 2018-11-13 Sumitomo Metal Mining Co. Ltd. Method for producing hematite for ironmaking

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5622061B2 (ja) * 2013-03-26 2014-11-12 住友金属鉱山株式会社 製鉄用ヘマタイトの製造方法
JP5440823B1 (ja) * 2013-09-18 2014-03-12 住友金属鉱山株式会社 製鉄用ヘマタイトの製造方法
CN106673071B (zh) * 2016-12-23 2019-01-11 天津理工大学 一种红土镍矿酸浸液除铁同时生产氧化铁黑颜料的方法

Citations (15)

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US2719082A (en) * 1951-06-11 1955-09-27 Int Nickel Co Method for producing high grade hematite from nickeliferous iron sulfide ore
US2796340A (en) * 1954-02-04 1957-06-18 New Jersey Zinc Co Process for roasting sulfide ore concentrates
US2867506A (en) * 1956-07-18 1959-01-06 Dorr Oliver Inc Producing sulphur dioxide gas
US3042498A (en) * 1952-06-04 1962-07-03 Int Nickel Co Apparatus for roasting sulfides
US3093559A (en) * 1958-06-20 1963-06-11 Merwin G White Treatment of lateritic ores
US3232744A (en) * 1961-11-16 1966-02-01 Inst Noguchi Process for producing iron oxide with a low silica content
US3671197A (en) * 1970-02-05 1972-06-20 Lummus Co Treatment of pyrites
US3854931A (en) * 1970-04-20 1974-12-17 Boliden Ab Roasting, coarsening and hardening of iron sulfide materials
US3957484A (en) * 1973-10-09 1976-05-18 Simon Otto Fekete Fluid bed roasting of metal sulphides at high temperatures
US4069041A (en) * 1975-07-01 1978-01-17 Boliden Aktiebolag Method of recovering non-ferrous metals from sulphidic materials
US4572822A (en) * 1982-02-15 1986-02-25 Dowa Mining Co., Ltd. Method of recovering metals from industrial by-products
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2719082A (en) * 1951-06-11 1955-09-27 Int Nickel Co Method for producing high grade hematite from nickeliferous iron sulfide ore
US3042498A (en) * 1952-06-04 1962-07-03 Int Nickel Co Apparatus for roasting sulfides
US2796340A (en) * 1954-02-04 1957-06-18 New Jersey Zinc Co Process for roasting sulfide ore concentrates
US2867506A (en) * 1956-07-18 1959-01-06 Dorr Oliver Inc Producing sulphur dioxide gas
US3093559A (en) * 1958-06-20 1963-06-11 Merwin G White Treatment of lateritic ores
US3232744A (en) * 1961-11-16 1966-02-01 Inst Noguchi Process for producing iron oxide with a low silica content
US3671197A (en) * 1970-02-05 1972-06-20 Lummus Co Treatment of pyrites
US3854931A (en) * 1970-04-20 1974-12-17 Boliden Ab Roasting, coarsening and hardening of iron sulfide materials
US3957484A (en) * 1973-10-09 1976-05-18 Simon Otto Fekete Fluid bed roasting of metal sulphides at high temperatures
US4069041A (en) * 1975-07-01 1978-01-17 Boliden Aktiebolag Method of recovering non-ferrous metals from sulphidic materials
US4572822A (en) * 1982-02-15 1986-02-25 Dowa Mining Co., Ltd. Method of recovering metals from industrial by-products
JP2001032002A (ja) * 1999-07-16 2001-02-06 Sumitomo Metal Mining Co Ltd 酸化ニッケル粉末の製造方法
US20050265910A1 (en) * 2004-05-13 2005-12-01 Sumitomo Metal Mining Co., Ltd. Hydrometallurgical process of nickel oxide ore
US20060133974A1 (en) * 2004-12-22 2006-06-22 Placer Dome Technical Services Limited Reduction of lime consumption when treating refractory gold ores or concentrates
US8052774B2 (en) * 2009-03-31 2011-11-08 Sumitomo Metal Mining Co., Ltd. Method for concentration of gold in copper sulfide minerals

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10125025B2 (en) 2014-02-27 2018-11-13 Sumitomo Metal Mining Co. Ltd. Method for producing hematite for ironmaking

Also Published As

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AU2013236727A1 (en) 2014-10-09
EP2829516A1 (en) 2015-01-28
JP2013193923A (ja) 2013-09-30
JP5424139B2 (ja) 2014-02-26
CN104203830B (zh) 2016-11-16
CA2867672A1 (en) 2013-09-26
CA2867672C (en) 2017-08-15
CN104203830A (zh) 2014-12-10
EP2829516B1 (en) 2018-12-26
PH12014502100A1 (en) 2014-12-10
WO2013140837A1 (ja) 2013-09-26
AU2013236727B2 (en) 2016-06-30
EP2829516A4 (en) 2015-12-09
PH12014502100B1 (en) 2014-12-10

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