WO1995031577A1 - Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates - Google Patents
Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates Download PDFInfo
- Publication number
- WO1995031577A1 WO1995031577A1 PCT/US1994/005376 US9405376W WO9531577A1 WO 1995031577 A1 WO1995031577 A1 WO 1995031577A1 US 9405376 W US9405376 W US 9405376W WO 9531577 A1 WO9531577 A1 WO 9531577A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- molten
- pyrrhotite
- silver
- gold
- precious metals
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 40
- 230000008569 process Effects 0.000 title claims abstract description 38
- 239000004332 silver Substances 0.000 title claims abstract description 37
- 229910052737 gold Inorganic materials 0.000 title claims abstract description 36
- 239000010931 gold Substances 0.000 title claims abstract description 36
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 36
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 title claims abstract description 35
- NIFIFKQPDTWWGU-UHFFFAOYSA-N pyrite Chemical compound [Fe+2].[S-][S-] NIFIFKQPDTWWGU-UHFFFAOYSA-N 0.000 title claims abstract description 17
- 229910052683 pyrite Inorganic materials 0.000 title claims abstract description 17
- 239000011028 pyrite Substances 0.000 title claims abstract description 17
- 238000011084 recovery Methods 0.000 title claims description 13
- MJLGNAGLHAQFHV-UHFFFAOYSA-N arsenopyrite Chemical compound [S-2].[Fe+3].[As-] MJLGNAGLHAQFHV-UHFFFAOYSA-N 0.000 title abstract description 9
- 229910052964 arsenopyrite Inorganic materials 0.000 title abstract description 9
- 239000012141 concentrate Substances 0.000 title description 4
- 229910052952 pyrrhotite Inorganic materials 0.000 claims abstract description 38
- 239000010970 precious metal Substances 0.000 claims abstract description 27
- 238000003723 Smelting Methods 0.000 claims abstract description 16
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 16
- 239000011701 zinc Substances 0.000 claims abstract description 16
- 239000007791 liquid phase Substances 0.000 claims abstract description 6
- 230000005012 migration Effects 0.000 claims abstract description 3
- 238000013508 migration Methods 0.000 claims abstract description 3
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 28
- 239000000295 fuel oil Substances 0.000 claims description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 5
- 239000007789 gas Substances 0.000 claims description 5
- 229910052760 oxygen Inorganic materials 0.000 claims description 5
- 239000001301 oxygen Substances 0.000 claims description 5
- 230000004907 flux Effects 0.000 claims description 4
- 239000000446 fuel Substances 0.000 claims description 4
- 239000010742 number 1 fuel oil Substances 0.000 claims description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000010949 copper Substances 0.000 claims description 3
- 239000002529 flux (metallurgy) Substances 0.000 claims description 2
- 238000012423 maintenance Methods 0.000 claims 1
- 238000010438 heat treatment Methods 0.000 abstract description 3
- 229910052751 metal Inorganic materials 0.000 description 8
- 239000002184 metal Substances 0.000 description 8
- 239000006227 byproduct Substances 0.000 description 6
- 206010039509 Scab Diseases 0.000 description 5
- 238000012545 processing Methods 0.000 description 5
- MBMLMWLHJBBADN-UHFFFAOYSA-N Ferrous sulfide Chemical compound [Fe]=S MBMLMWLHJBBADN-UHFFFAOYSA-N 0.000 description 4
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 4
- 239000012071 phase Substances 0.000 description 4
- 150000004763 sulfides Chemical class 0.000 description 4
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 229910052787 antimony Inorganic materials 0.000 description 3
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 3
- 229910052785 arsenic Inorganic materials 0.000 description 3
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 description 3
- 229910052797 bismuth Inorganic materials 0.000 description 3
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 description 3
- 239000000428 dust Substances 0.000 description 3
- HJTAZXHBEBIQQX-UHFFFAOYSA-N 1,5-bis(chloromethyl)naphthalene Chemical compound C1=CC=C2C(CCl)=CC=CC2=C1CCl HJTAZXHBEBIQQX-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- GOLCXWYRSKYTSP-UHFFFAOYSA-N arsenic trioxide Inorganic materials O1[As]2O[As]1O2 GOLCXWYRSKYTSP-UHFFFAOYSA-N 0.000 description 2
- 238000010981 drying operation Methods 0.000 description 2
- 238000005469 granulation Methods 0.000 description 2
- 230000003179 granulation Effects 0.000 description 2
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000010802 sludge Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910001316 Ag alloy Inorganic materials 0.000 description 1
- 229910001020 Au alloy Inorganic materials 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910002065 alloy metal Inorganic materials 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 230000003750 conditioning effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 239000003353 gold alloy Substances 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- LWUVWAREOOAHDW-UHFFFAOYSA-N lead silver Chemical compound [Ag].[Pb] LWUVWAREOOAHDW-UHFFFAOYSA-N 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000009853 pyrometallurgy Methods 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- 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
-
- 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
- This invention relates to a process for the recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates.
- this invention provides for a pyrometallurgical process for the recovery of gold and silver which avoids production of oxide gas by-products.
- the present invention is directed to a process for recovering precious metals from complex pyrite ores comprising the steps of smelting the pyrite, obtaining molten pyrrhotite, contacting a layer of molten pyrrhotite containing a quantity of precious metals to be recovered with a layer of molten lead at a temperature where both layers exist as substantially separate liquid phases, and obtaining the migration of the precious metals from the pyrrhotite to the molten lead.
- the process eliminates any significant quantity of gaseous oxide by-products.
- Figs. 1A and IB are a schematic representation of a preferred embodiment of the process of the present invention.
- a charge of pyrites and/or arsenopyrites containing gold and silver, fluxes, and coal and/or fuel oil is fed to and smelted in a cyclone furnace under reducing conditions.
- the coal or fuel oil is used to supply heat for smelting.
- Oxygen is kept below the stoichiometric requirement to burn the fuel for smelting (i.e. 0.5% free oxygen) to obtain molten iron sulfide containing the gold and silver from the charge at the bottom of the cyclone furnace.
- the product of the smelted charge which includes molten iron sulphide, gold, silver, and other products from the smelting of complex pyrite and arsenopyrite ores is referred to herein as pyrrhotite.
- Gases of this smelting operation consist mainly of elemental sulfur and other sulfides (i.e. arsenic, antimony, lead, bismuth, etc.). Only minimum amounts of sulfur dioxide or arsenic trioxide are generated due to the virtual absence of free oxygen in the smelting environment.
- Molten pyrrhotite exits the cyclone furnace and flows directly into a holding furnace, a modified reverb furnace, connected to the bottom of the cyclone furnace.
- the holding furnace contains a molten metallic lead bath.
- the pyrrhotite When the molten pyrrhotite enters the holding furnace and contacts the molten lead, the pyrrhotite remains as a separate and distinct phase residing on the surface of the molten lead due to the lower density of the pyrrhotite.
- temperatures ranging from about 1,100 to about 1,200 °C, where both phases coexist in the liquid state the gold and silver migrate from the pyrrhotite to the molten lead phase.
- the precious metals contained in the molten pyrrhotite are effectively transferred to the molten lead phase which is acting as a collector of the gold and silver.
- the molten pyrrhotite substantially barren of precious metals, flows continuously off the opposite end of the holding furnace for granulation and storage.
- the molten lead now enriched with gold and silver remains in the holding furnace, until further processing takes place.
- the molten lead bath in the holding furnace becomes progressively enriched with precious metals throughout the process.
- enriched lead is tapped from the holding furnace into a steel holding pot for precious metals recovery.
- Any recovery method known to those in the art may be used to remove the gold and silver.
- a zinc desilverizing process which is known to those in the art, is useful for removing gold and silver values from an enriched molten lead bath.
- the depleted lead from the desilverizing operation is reheated and fed back to the holding furnace in a closed circuit operation to replenish the lead bath.
- the zinc crust obtained during the desilverizing operation now contains most of the gold and silver previously dissolved in the enriched molten lead.
- This crust is skimmed off the top of the molten lead at temperatures near the freezing point of lead (i.e. 320 °C) , and is cast into slabs for further processing.
- the slabs of zinc crust are smelted in a retort furnace for removal of the zinc. As zinc metal settles in the condenser of the retort furnace, it separates from a lead/silver/gold alloy metal.
- This alloy metal is cast in bars and fed into a cupel furnace for the removal of lead and any copper or other residual metals, if present, in order to produce an alloy containing 98-99% of gold and silver (Dore metal) .
- the Dore metal may then be shipped out to refiners.
- This process can be defined in more detail with reference to Figs. 1A and IB.
- a blend of ores or concentrates of pyrites and/or arsenopyrites containing gold and silver, along with fluxes and coal make up the charge 1.
- Charge 1 is placed in a hopper 2, preferably by use of a front end loader.
- the charge is uniformly fed by means of a first conveyor belt 3 to a rotary dryer 4 where moisture in the charge is reduced to 1-2% by weight.
- a fraction of the charge is collected as dust produced as a result of the drying operation. Dust may be collected by means of a baghouse system 5 connected to the discharge end of the dryer 4, and then the dust may be fed back to a screw conveyor 6.
- the dry charge stored in the hopper 8 is transported and continuously fed by means of a third belt conveyor 9 to the cyclone furnace 10.
- the cyclone furnace 10 is a vertical cylindrical stainless steel water jacketed vessel, fired by four high speed fuel oil burners using air preheated to 250 °C.
- the charge enters the cyclone furnace 10 centered and is rapidly smelted due to burner heat and the cyclonic effect on the charge.
- the charge releases elemental sulfur and other minor sulfides if present in the ore (i.e. arsenic, antimony, lead, bismuth, etc.) in gaseous form.
- the smelted charge will contain mainly iron sulfide (pyrrhotite) and precious metals (gold, silver) and will flow down the wall of the cyclone furnace 10 and into the holding furnace 11 that holds a bath of molten metallic lead.
- the gases from the smelting operation in the cyclone furnace 10 flow into the holding furnace 11 together with the molten charge, then along the holding furnace 11 and out of the opposite end to the cooling tower 12, where water is added, on to a wet venturi scrubber 13, and out into a cyclonic separator 14.
- a sludge is recovered and transferred to settling ponds for storage and disposal.
- the sludge will contain elemental sulfur as indicated above and other non-ferric sulfides, if present in the ore (i.e. arsenic, antimony, bismuth, etc.), along with pulp conditioning materials such as lime.
- the clean gas will be drawn up by an exhaust fan 15 positioned next to the separator 14, which will direct it to the stack 16, where it is released to the environment.
- the molten pyrrhotite that settles in the holding furnace 11 will form a distinctive liquid phase on top of the molten lead bath and will flow from one end of the holding furnace 11 to the other, releasing its precious metals to the lead and overflowing at the discharge end of the holding furnace 11, for granulation and storage.
- the enriched lead remains in the holding furnace 11 until further processing takes place.
- the enriched lead bath held at the holding furnace 11 is tapped and discharged into a holding pot 18 where zinc is added, stirred at 450 °C, and then allowed to coo! to 320 °C.
- the remaining molten lead (virtually free of gold and silver) is pumped to another heating pot 17 for heating. Heated desilverized lead is pumped back to the holding furnace 11 to replenish the molten lead bath.
- the zinc crust formed in the desilverizing operation becomes enriched with gold and silver and is cast for further processing in the zinc retort furnaces 19, where zinc is recovered as zinc metal to return to the desilverizing operation and a lead silver gold bullion is produced.
- the bullion is melted in the cupel furnace 20 and oxidized with air to remove the contained lead and copper and most of the other trace metals. This leaves behind an approximately 98- 99% pure Dore metal, that is cast into slabs for resale.
Landscapes
- 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)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU73113/94A AU7311394A (en) | 1994-05-12 | 1994-05-12 | Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates |
PCT/US1994/005376 WO1995031577A1 (en) | 1994-05-12 | 1994-05-12 | Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates |
PE1994246533A PE6895A1 (en) | 1994-05-12 | 1994-07-13 | PROCESS FOR THE RECOVERY OF GOLD AND SILVER OF MINERALS AND PIRITE AND ARSENOPYRITE COMPLEX CONCENTRATES |
ZA953738A ZA953738B (en) | 1994-05-12 | 1995-05-09 | Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates |
CO95019788A CO4520149A1 (en) | 1994-05-12 | 1995-05-11 | PROCESS FOR THE RECOVERY OF GOLD AND SILVER FROM MINERALS AND CONCENTRATES PIRITE AND ARSENOPYRITE |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US1994/005376 WO1995031577A1 (en) | 1994-05-12 | 1994-05-12 | Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1995031577A1 true WO1995031577A1 (en) | 1995-11-23 |
Family
ID=22242564
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1994/005376 WO1995031577A1 (en) | 1994-05-12 | 1994-05-12 | Process for recovery of gold and silver from complex pyrite and arsenopyrite ores and concentrates |
Country Status (5)
Country | Link |
---|---|
AU (1) | AU7311394A (en) |
CO (1) | CO4520149A1 (en) |
PE (1) | PE6895A1 (en) |
WO (1) | WO1995031577A1 (en) |
ZA (1) | ZA953738B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2520902C2 (en) * | 2012-09-28 | 2014-06-27 | Лидия Алексеевна Воропанова | Extraction of heavy metals, iron, gold and silver from sulphate cake |
RU2559600C2 (en) * | 2010-07-15 | 2015-08-10 | Гленкор Текнолоджи Пти Лимитед | Pyrometallurgical method |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1808594A (en) * | 1927-02-04 | 1931-06-02 | Louyot Comptoir Lyon Alemand | Process for separating platinum from the other precious metals |
US3463633A (en) * | 1967-03-01 | 1969-08-26 | Jack W Petty | Metal recovery method |
US4416692A (en) * | 1981-02-23 | 1983-11-22 | Burch Glen R | Process for extracting gold, silver, platinum, lead, or manganese metals from ore |
US4734129A (en) * | 1985-06-10 | 1988-03-29 | Britannia Refined Metals Limited | Recovery of metals from their alloys with lead using consummable lance and apparatus |
-
1994
- 1994-05-12 AU AU73113/94A patent/AU7311394A/en not_active Abandoned
- 1994-05-12 WO PCT/US1994/005376 patent/WO1995031577A1/en active Application Filing
- 1994-07-13 PE PE1994246533A patent/PE6895A1/en not_active Application Discontinuation
-
1995
- 1995-05-09 ZA ZA953738A patent/ZA953738B/en unknown
- 1995-05-11 CO CO95019788A patent/CO4520149A1/en unknown
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1808594A (en) * | 1927-02-04 | 1931-06-02 | Louyot Comptoir Lyon Alemand | Process for separating platinum from the other precious metals |
US3463633A (en) * | 1967-03-01 | 1969-08-26 | Jack W Petty | Metal recovery method |
US4416692A (en) * | 1981-02-23 | 1983-11-22 | Burch Glen R | Process for extracting gold, silver, platinum, lead, or manganese metals from ore |
US4734129A (en) * | 1985-06-10 | 1988-03-29 | Britannia Refined Metals Limited | Recovery of metals from their alloys with lead using consummable lance and apparatus |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2559600C2 (en) * | 2010-07-15 | 2015-08-10 | Гленкор Текнолоджи Пти Лимитед | Pyrometallurgical method |
RU2520902C2 (en) * | 2012-09-28 | 2014-06-27 | Лидия Алексеевна Воропанова | Extraction of heavy metals, iron, gold and silver from sulphate cake |
Also Published As
Publication number | Publication date |
---|---|
ZA953738B (en) | 1996-01-11 |
PE6895A1 (en) | 1995-04-20 |
CO4520149A1 (en) | 1997-10-15 |
AU7311394A (en) | 1995-12-05 |
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