US20050217422A1 - Method for refining concentrate containing precious metals - Google Patents

Method for refining concentrate containing precious metals Download PDF

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Publication number
US20050217422A1
US20050217422A1 US10/513,164 US51316404A US2005217422A1 US 20050217422 A1 US20050217422 A1 US 20050217422A1 US 51316404 A US51316404 A US 51316404A US 2005217422 A1 US2005217422 A1 US 2005217422A1
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US
United States
Prior art keywords
matte
smelting furnace
suspension smelting
furnace
slag
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
US10/513,164
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English (en)
Inventor
Tuula Makinen
Minna Eerola
Jukka Laulumaa
Ilkka Kojo
Nils Merikanto
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.)
Metso Outotec Oyj
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
Assigned to OUTOKUMPU OYJ reassignment OUTOKUMPU OYJ ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: EEROLA, MINNA, LAULUMAA, JUKKA, KOJO, ILKKA, MAKINEN, TUULA, MERIKANTO, NILS
Publication of US20050217422A1 publication Critical patent/US20050217422A1/en
Assigned to OUTOKUMPU TECHNOLOGY OY reassignment OUTOKUMPU TECHNOLOGY OY CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: OUTOKUMPU OYJ
Abandoned legal-status Critical Current

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    • 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
    • C22B23/02—Obtaining nickel or cobalt by dry processes
    • C22B23/025—Obtaining nickel or cobalt by dry processes with formation of a matte or by matte refining or converting into nickel or cobalt, e.g. by the Oxford process
    • 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
    • C22B11/00—Obtaining noble metals
    • C22B11/02—Obtaining noble metals by dry processes
    • 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
    • C22B11/00—Obtaining noble metals
    • C22B11/04—Obtaining noble metals by wet processes
    • 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
    • C22B23/0407—Leaching processes
    • C22B23/0415—Leaching processes with acids or salt solutions except ammonium salts solutions
    • 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 invention relates to a method for refining precious metal concentrate defined in the preamble of claim 1 .
  • a supension smelting furnace there is used a supension smelting furnace; the matte created in said furnace is conducted into hydrometallurgical treatment, and the slag is reduced in an electric furnace.
  • the metallicized matte created in the electric furnace is either fed back into the suspension smelting furnace or to hydrometallurgical treatment together or separately with the matte from the suspension smelting furnace.
  • precious metals Au, Ag, Pt, Pd, Rh and Ir are in the world produced by using various different manufacturing methods.
  • Gold is produced either directly, by making use of the special features of gold, or as a side product in traditional copper production.
  • the majority of world's platinum and a remarkable share of palladium is produced by using primary electric furnaces.
  • the majority of world's palladium production is mainly based on nickel side production from ores by means of the suspension technique, where the obtained intermediate product is nickel concentrate.
  • An essential step in both processes is the use of a converter as part of the process.
  • the use of a converter in the processes is harmful, as sulfur dioxide emissions and intermediate products caused by the transportation of melts are increased.
  • Mattes obtained in the above described ways are further treated in hydrometallurgic plants. There are several different hydrometallurgical processes for the further refining of matte obtained from smelting, when precious metals should be recovered as side products.
  • the Finnish patent application 890 395 describes a manufacturing method and arrangement for producing high-grade nickel matte.
  • high-grade nickel matte is directly produced in a suspension smelting furnace.
  • At least the slag from the suspension smelting furnace is reduced in an electric furnace, where the electric furnace slag and the metallicized matte are formed, so that at least part of the metallicized matte is returned as feed to the suspension smelting furnace.
  • the object of the present invention is to bring forth a new type of method for refining precious metal concentrate, so that the precious metals are advantageously recovered by making use of the suspension smelting process.
  • Another object of the invention is to realize a refining process for a concentrate, the value of which lies in the precious metals contained therein, and where the nickel and/or copper only represent a side product in value.
  • the invention is characterized by what is set forth in the characterizing part of claim 1 .
  • Other embodiments of the invention are characterized by what is set forth in the rest of the claims.
  • the method according to the invention for refining precious metal concentrate has several advantages.
  • the invention relates to a method for refining precious metal concentrate, and according to said method, at least the treated precious metal concentrate, the reaction gas, the slag forming agent, i.e. flux, and the flue dust are together fed into the reaction shaft of a suspension smelting furnace, so that in the suspension smelting furnace, there are created separate phases, matte and slag.
  • the slag created in the suspension smelting furnace is conducted to an electric furnace, where metallicized matte and waste slag are formed, whereafter the matte from the suspension smelting furnace is conducted to hydrometallurgical treatment, and the slag conducted into the electric furnace is processed together with a reducing agent and possibly an agent that lowers the melting point or improves fluidity, and the created metallicized matte is conducted either to hydrometallurgical treatment or back into the suspension smelting furnace.
  • a suspension smelting furnace such as a flash smelting furnace.
  • the method according to the invention for refining precious metal concentrate can also be utilized so that part of the supplied precious metal concentrate is replaced by sulfide concentrate.
  • the process according to the invention essentially differs from said publications (FI patent 890,395 and FI patent 94538), because the raw material used in the process is precious metal concentrate and not nickel concentrate, wherefore high-grade nickel matte is not created.
  • the matte obtained from a suspension smelting furnace and the metallicized matte obtained from an electric furnace are granulated prior to the hydrometallurgical treatment.
  • the matte from a suspension smelting furnace and the metallicized matte from an electric furnace are processed either in the same hydro metallurgical process or in different processes.
  • the matte from the suspension smelting furnace is leached at least in one step.
  • the metallicized matte from the electric furnace is leached at least in one step in the hydrometallurgical process.
  • the leaching of the matte takes place in sulfate atmosphere.
  • the leaching takes place in chloride atmosphere.
  • precious metals are recovered from the leach residue.
  • the ferrous precipitate created in the hydrometallurgical treatment of matte and metallicized matte is conducted to a suspension smelting furnace.
  • the energy contained by the raw material such as the oxidizing heat contained by iron and sulfur
  • the matte phase is separated from slag in two steps, both in the suspension smelting furnace and in the electric furnace, the recovery of precious metals is remarkably increased when compared to processing in a primary electric furnace.
  • the amount of created exhaust gases is remarkably smaller than when using only a primary electric furnace in the treatment of the concentrate.
  • dust losses are reduced.
  • a relatively smaller quantity of gas facilitates the recovery and manufacturing of sulfur dioxide either into pure sulfur dioxide or into sulfuric acid. Now the necessary investments related to the gas and sulfur dioxide are smaller than in a process based on a corresponding primary electric furnace fulfilling the ecological requirements.
  • the elimination of the use of converters results in the same advantages described above as the fact that primary electric furnaces are not used anymore.
  • FIG. 1 Description of the process according to the invention.
  • FIG. 1 illustrates a suspension smelting furnace 1 to be used in the method according to the invention, such as a flash smelting furnace.
  • a suspension smelting furnace 1 In the top part of the furnace reaction shaft 3 there is fed precious metal concentrate 9 , oxidizing reaction gas 10 , slag-forming agent, i.e. flux 11 and flue dust 12 obtained from the cooling of exhaust gases from the waste heat boiler 6 .
  • slag-forming agent i.e. flux 11 and flue dust 12 obtained from the cooling of exhaust gases from the waste heat boiler 6 .
  • iron precipitate created in the hydrometallurgic units 15 and 16 in the treatment of the matte.
  • the ingredients fed into the reaction shaft 3 react with each other, and on the bottom of the settler 4 , there is formed a matte layer 8 and on top of it a slag layer 7 .
  • the gases created in the suspension smelting furnace are removed through the uptake shaft 5 into a waste heat boiler 6 , wherefrom the created flue dusts 12 are recirculated back into the suspension smelting furnace, and the exhaust gases 18 are conducted for further processing.
  • a remarkable share of the concentrate 9 are precious metals that are accumulated in the settler, mainly in the matte phase 8 .
  • the matte 8 is subjected to granulation 17 , and it is conducted into hydrometallurgical further processing 15 , where the matte is leached, in which case the precious metals are leached last.
  • the slag 7 created in the suspension smelting furnace is conducted into an electric furnace 2 , in which, apart from oxidized slag and reducing agent, there also is fed, if necessary, a sulfurous or other material for lowering the melting point or for improving the fluidity in order to adjust the melting point of the matte to be created.
  • a sulfurous or other material for lowering the melting point or for improving the fluidity in order to adjust the melting point of the matte to be created.
  • metallicized matte 14 and slag 13 there is created metallicized matte 14 and slag 13 . Without a sulfur addition, the sulfur content of the metallicized matte may remain very low, and respectively the melting point and viscosity may remain high.
  • the precious metals are mainly transferred into a matte phase 14 , which is further conducted, according to the invention, either to hydrometallurgical treatment 16 , together with the matte from the suspension smelting furnace or separately.
  • Another alternative is to recirculate the metallicized matte 14 or part thereof back into the suspension smelting furnace 1 .
  • the matte Prior to the hydrometallurgical treatment 16 of the metallicized matte 14 , the matte is subjected to granulation 19 .
  • the slag 13 created in the electric furnace 2 is waste slag, i.e. it is discarded.
  • the precious metals are recovered in a hydrometallurgical process.
  • Both the matte 8 from the suspension smelting furnace and the metallicized matte 14 from the electric furnace are leached either in the same leaching line or separately.
  • the leaching steps are dependent on the contents of the precious metal concentrate to be treated.
  • the leaching is carried out in a sulfate atmosphere, i.e. the solution at some stage contains sulfate. Now the cobalt and nickel possibly contained in the concentrate are leached in the first selective pressure leaching step as sulfate.
  • leached iron that can at the same time be precipitated as iron hydroxide.
  • Nickel is recovered as salt, or it is turned into metal in the electrolysis.
  • copper is leached as copper sulfate, which can be separated as such or turned into metallic copper in the electrolysis. Copper sulfate can also be crystallized and fed back into the suspension smelting furnace after drying.
  • the precious metals are left in the leach residue.
  • the precious metal content of the leach residue is increased for instance by means of a strong sulfuric acid and sulfur dioxide treatment.
  • the created concentrated precipitate is a good raw material for various precious metal refineries.
  • the leaching is carried out in a chloride atmosphere, in which case there is used chloride gas in the leaching, and in the solution, there are created cobalt, nickel, copper and iron chlorides.
  • the method according to the invention was applied for the precious metal concentrate mentioned above, so that part of said concentrate was replaced by nickel concentrate.
  • the iron precipitate created in the hydrometallurgic unit was recirculated back into the suspension smelting furnace.
  • the abbreviation PGM means precious metals.
  • the gas created in a suspension smelting furnace contains more than 10% sulfur dioxide, and is thus suitable for the production of sulfuric acid.
  • the exhaust gases from the electric furnace are nearly free of sulfur dioxide, and consequently do not strain the environment.
  • the method described above also functions without nickel and even so that a large part of the copper is replaced by iron, if the source material does not contain a sufficient amount of copper.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US10/513,164 2002-05-03 2003-05-02 Method for refining concentrate containing precious metals Abandoned US20050217422A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FI2002-0835 2002-05-03
FI20020835A FI114808B (sv) 2002-05-03 2002-05-03 Förfarande för förädling av ädelmetallsslig
PCT/FI2003/000343 WO2003093516A1 (en) 2002-05-03 2003-05-02 Method for refining concentrate containing precious metals

Publications (1)

Publication Number Publication Date
US20050217422A1 true US20050217422A1 (en) 2005-10-06

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ID=8563870

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US10/513,164 Abandoned US20050217422A1 (en) 2002-05-03 2003-05-02 Method for refining concentrate containing precious metals

Country Status (15)

Country Link
US (1) US20050217422A1 (sv)
EP (1) EP1509628A1 (sv)
JP (1) JP2005524768A (sv)
KR (1) KR20040099476A (sv)
CN (1) CN1650037A (sv)
AU (1) AU2003240873A1 (sv)
BR (1) BR0309679A (sv)
CA (1) CA2484416A1 (sv)
EA (1) EA006620B1 (sv)
FI (1) FI114808B (sv)
MX (1) MXPA04010718A (sv)
PL (1) PL372600A1 (sv)
RS (1) RS95504A (sv)
WO (1) WO2003093516A1 (sv)
ZA (1) ZA200408570B (sv)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060037435A1 (en) * 2002-12-05 2006-02-23 Pekka Hanniala Method for treating slag
WO2013030449A1 (en) * 2011-08-29 2013-03-07 Outotec Oyj Method for recovering metals from sulphidic concentrate
US20130269481A1 (en) * 2012-04-16 2013-10-17 Xiangguang Copper Co., Ltd. Method for producing blister copper directly from copper concentrate
EP2861774A4 (en) * 2012-06-13 2016-03-30 Outotec Finland Oy PROCESS AND ARRANGEMENT FOR REFINING COPPER CONCENTRATE
US10662500B2 (en) 2018-01-24 2020-05-26 Heraeus Deutschland GmbH & Co. KG Process for the recovery of precious metal from petrochemical process residues
US11155894B2 (en) * 2016-04-28 2021-10-26 Eldorado Gold Corporation Method for reducing arsenic content in arsenic-bearing gold material

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI119774B (sv) * 2007-06-20 2009-03-13 Outotec Oyj Förfarande för behandling av kobolthaltigt kopparkoncentrat
FI120157B (sv) * 2007-12-17 2009-07-15 Outotec Oyj Förfarande för förädling av kopparslig
JP5609121B2 (ja) * 2010-01-21 2014-10-22 新日鐵住金株式会社 銅鉄スクラップ中の白金を回収するための白金の溶銅相への濃化方法
RU2531333C2 (ru) * 2012-06-25 2014-10-20 Радик Расулович Ахметов Способ извлечения металлов платиновой группы из отработанных автомобильных катализаторов
CN104451195B (zh) * 2014-11-21 2016-05-18 邱江波 红土镍矿的闪速熔炼方法
CN104561519A (zh) * 2014-12-03 2015-04-29 金川集团股份有限公司 一种高镁贵金属精矿的处理方法
RU2614293C2 (ru) * 2015-06-04 2017-03-24 Общество с ограниченной ответственностью "Институт Гипроникель" Способ переработки низкоавтогенного сырья в печах взвешенной плавки
CN107119195B (zh) * 2017-04-27 2019-01-04 山东河西黄金集团有限公司 基于高S高Fe金矿与含铜废料直接熔炼回收金和铜的方法
CN112359227B (zh) * 2020-11-12 2022-05-20 中国恩菲工程技术有限公司 从火法炼镍过程中提钴的方法
CN115433838A (zh) * 2022-08-15 2022-12-06 金川镍钴研究设计院有限责任公司 一种火法处理尼尔森精矿富集贵金属的方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4021235A (en) * 1974-10-28 1977-05-03 Nihon Kogyo Kabushiki Kaisha Operating method for slag cleaning furnace in copper refining
US4388110A (en) * 1980-12-01 1983-06-14 Boliden Aktiebolag Method for recovering the metal content of complex sulphidic metal raw materials
US4613365A (en) * 1984-09-28 1986-09-23 Boliden Aktiebolag Method for recovering precious metals
US5332414A (en) * 1992-06-18 1994-07-26 Outokumpu Harjavalta Metals Oy Method for producing high-grade nickel matte and metallized sulfide matte
US5487819A (en) * 1992-06-26 1996-01-30 Intec Pty Ltd Production of metals from minerals
US6039790A (en) * 1995-08-14 2000-03-21 Outkumpu Technology Oy Method for recovering nickel hydrometallurgically from two different nickel mattes

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI84368B (fi) * 1989-01-27 1991-08-15 Outokumpu Osakeyhtioe Foerfarande och anlaeggning foer framstaellning av nickelfinsten.

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4021235A (en) * 1974-10-28 1977-05-03 Nihon Kogyo Kabushiki Kaisha Operating method for slag cleaning furnace in copper refining
US4388110A (en) * 1980-12-01 1983-06-14 Boliden Aktiebolag Method for recovering the metal content of complex sulphidic metal raw materials
US4613365A (en) * 1984-09-28 1986-09-23 Boliden Aktiebolag Method for recovering precious metals
US5332414A (en) * 1992-06-18 1994-07-26 Outokumpu Harjavalta Metals Oy Method for producing high-grade nickel matte and metallized sulfide matte
US5487819A (en) * 1992-06-26 1996-01-30 Intec Pty Ltd Production of metals from minerals
US6039790A (en) * 1995-08-14 2000-03-21 Outkumpu Technology Oy Method for recovering nickel hydrometallurgically from two different nickel mattes

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060037435A1 (en) * 2002-12-05 2006-02-23 Pekka Hanniala Method for treating slag
WO2013030449A1 (en) * 2011-08-29 2013-03-07 Outotec Oyj Method for recovering metals from sulphidic concentrate
US20130269481A1 (en) * 2012-04-16 2013-10-17 Xiangguang Copper Co., Ltd. Method for producing blister copper directly from copper concentrate
US8771396B2 (en) * 2012-04-16 2014-07-08 Xiangguang Copper Co., Ltd. Method for producing blister copper directly from copper concentrate
EP2861774A4 (en) * 2012-06-13 2016-03-30 Outotec Finland Oy PROCESS AND ARRANGEMENT FOR REFINING COPPER CONCENTRATE
US9580771B2 (en) 2012-06-13 2017-02-28 Outotec (Finland) Oy Method and arrangement for refining copper concentrate
US11155894B2 (en) * 2016-04-28 2021-10-26 Eldorado Gold Corporation Method for reducing arsenic content in arsenic-bearing gold material
US10662500B2 (en) 2018-01-24 2020-05-26 Heraeus Deutschland GmbH & Co. KG Process for the recovery of precious metal from petrochemical process residues

Also Published As

Publication number Publication date
AU2003240873A1 (en) 2003-11-17
CA2484416A1 (en) 2003-11-13
RS95504A (en) 2007-02-05
WO2003093516A1 (en) 2003-11-13
KR20040099476A (ko) 2004-11-26
PL372600A1 (en) 2005-07-25
EA006620B1 (ru) 2006-02-24
JP2005524768A (ja) 2005-08-18
FI114808B (sv) 2004-12-31
BR0309679A (pt) 2005-03-01
EA200401237A1 (ru) 2005-06-30
FI20020835A (sv) 2003-11-04
EP1509628A1 (en) 2005-03-02
MXPA04010718A (es) 2005-03-07
ZA200408570B (en) 2005-04-22
CN1650037A (zh) 2005-08-03
FI20020835A0 (sv) 2002-05-03

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Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MAKINEN, TUULA;EEROLA, MINNA;LAULUMAA, JUKKA;AND OTHERS;REEL/FRAME:016625/0893;SIGNING DATES FROM 20040922 TO 20040924

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