AU2002254782B2 - Bioleaching of a sulphide concentrate in a saline solution - Google Patents
Bioleaching of a sulphide concentrate in a saline solution Download PDFInfo
- Publication number
- AU2002254782B2 AU2002254782B2 AU2002254782A AU2002254782A AU2002254782B2 AU 2002254782 B2 AU2002254782 B2 AU 2002254782B2 AU 2002254782 A AU2002254782 A AU 2002254782A AU 2002254782 A AU2002254782 A AU 2002254782A AU 2002254782 B2 AU2002254782 B2 AU 2002254782B2
- Authority
- AU
- Australia
- Prior art keywords
- bioleaching
- saline solution
- ppm
- excess
- mineral
- 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.)
- Ceased
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- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 title claims description 22
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 title claims description 15
- 239000012141 concentrate Substances 0.000 title claims description 12
- 241000894006 Bacteria Species 0.000 claims description 23
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 18
- 238000000034 method Methods 0.000 claims description 18
- 239000011707 mineral Substances 0.000 claims description 18
- 238000002386 leaching Methods 0.000 claims description 16
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 14
- 150000003839 salts Chemical class 0.000 claims description 14
- 244000005700 microbiome Species 0.000 claims description 3
- 235000015097 nutrients Nutrition 0.000 description 7
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 241000321173 Acidihalobacter prosperus Species 0.000 description 5
- 239000013505 freshwater Substances 0.000 description 5
- 230000010261 cell growth Effects 0.000 description 4
- 150000002739 metals Chemical class 0.000 description 4
- 241000203069 Archaea Species 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 239000011780 sodium chloride Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 241000033824 Acidihalobacter Species 0.000 description 2
- 241000033825 Acidihalobacter ferrooxidans Species 0.000 description 2
- 241000605222 Acidithiobacillus ferrooxidans Species 0.000 description 2
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 2
- 229940041514 candida albicans extract Drugs 0.000 description 2
- 239000003575 carbonaceous material Substances 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 230000012010 growth Effects 0.000 description 2
- 230000015784 hyperosmotic salinity response Effects 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 239000013535 sea water Substances 0.000 description 2
- 239000012138 yeast extract Substances 0.000 description 2
- 241000605272 Acidithiobacillus thiooxidans Species 0.000 description 1
- 241000589921 Leptospirillum ferrooxidans Species 0.000 description 1
- 241001134777 Sulfobacillus Species 0.000 description 1
- 241000216226 Sulfolobus metallicus Species 0.000 description 1
- 229910001748 carbonate mineral Inorganic materials 0.000 description 1
- DVRDHUBQLOKMHZ-UHFFFAOYSA-N chalcopyrite Chemical compound [S-2].[S-2].[Fe+2].[Cu+2] DVRDHUBQLOKMHZ-UHFFFAOYSA-N 0.000 description 1
- 229910052951 chalcopyrite Inorganic materials 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 238000003973 irrigation Methods 0.000 description 1
- 230000002262 irrigation Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000000813 microbial effect Effects 0.000 description 1
- 239000000126 substance Substances 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
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/18—Extraction of metal compounds from ores or concentrates by wet processes with the aid of microorganisms or enzymes, e.g. bacteria or algae
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Microbiology (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Biochemistry (AREA)
- Materials Engineering (AREA)
- Biotechnology (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Processing Of Solid Wastes (AREA)
Description
WO 02/081761 PCT/ZA02/00062 BIOLEACHING OF A SULPHIDE CONCENTRATE IN A SALINE SOLUTION BACKGROUND OF THE INVENTION This invention relates generally to the bioleaching of a sulphide concentrate or a sulphide mineral ore in a saline solution, to recover contained metals.
Commercial bioleach operations require the use of water with a chloride content of less than 5000 ppm CI for heap leaching, and less than 1000 ppm CI in tank leaching. The use of water with a low chloride content is necessary because the mesophile or moderate thermophile bacteria used, such as Thiobacillus thiooxidans, Thiobacillus ferrooxidans, Leptospirillum ferrooxidans and Sulfobacillus strains, are not tolerant to high chloride concentrations. At chloride concentrations above 5000 ppm growth of the mesophile bacterium Thiobacillus ferrooxidans is inhibited and attempts to adapt the bacterium to chloride have proved unsuccessful. (1) Thermophile archaea such as Sulfolobus metallicus or other Sulfolobus-like archaea are particularly sensitive to chloride in solution. Microbial growth is reported to be prevented at concentrations of greater than 1000 ppm C-.
The limited tolerance to salt of bacteria and archaea currently used in commercial bioleaching operations means that large volumes of fresh water are required in the mineral processing operations. Many ore deposits are however situated in arid areas in which fresh water supplies are limited. The cost and availability of fresh water can therefore inhibit the recovery of the desired metals.
WO 02/081761 PCT/ZA02/00062 2 SUMMARY OF THE INVENTION The invention provides a method of treating a sulphide mineral which includes the step of bioleaching the mineral in a saline solution using at least one salt tolerant bacterium.
Preferably the bacterium is selected from the microorganisms deposited at the German Culture Collection under the respective accession Nos. DSM 14175 and DSM 14174, and a salt tolerant strain of Thiobacillus prosperus.
The bacterium may include at least one of Acidihalobacter ferrooxidans and Acidihalobacter aeolicus.
The salt tolerant strain of Thiobacillus prosperus may be a naturally occurring strain extracted from a natural or man made environment with appropriate environmental characteristics eg. a thermal spring with a pH of less than 4 and with a chloride content greater than 5000 ppm and, preferably, in excess of 10000 ppm, or for example from sea water with a high ferrous iron content and with a reduced pH of less than 3 and 4, or it may be adapted for the purpose.
The chloride content in the solution may be in excess of 5 000 ppm, and at least 10 000 ppm and, without being limiting, as high as 30 000 ppm or 35000 ppm or more.
The temperature at which bioleaching takes place may lie in excess thereof in the range of from 10°C to 45 0 C and may be determined at least according to circumstances.
Preferably though, when the method of the invention is used in a heap leaching situation, the temperature is in the range of from 10°C to 25 0 C. On the other hand, in 00 C tank leaching, for example in a stirred reactor, a higher temperature range applies and the temperature may be above 25 0 C and preferably lies in the range of from 35 0 C to 45 0
C.
00oo Nutrients may be added to the saline solution to maintain cell growth. In this c regard use may be made of a carbonaceous material, e. g. carbon dioxide or Scarbonate minerals, which is added in a suitable manner to the saline solution.
For example in tank leaching the carbonaceous material may be added to the tank or to a concentrate feed to the tank.
The nutrients may include a yeast extract.
According to the invention there is also provided a method of treating a sulphide mineral which includes the step of bioleaching the mineral in a saline solution with a chloride content in excess of 5000 ppm and at a temperature in excess of 100 C, with at least one salt tolerant bacterium, wherein the bacterium is selected from the microorganisms deposited at the German Culture Collection under the respective accession Nos. DSM 14175 and DSM 14174.
Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
00 3A C Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were 00 oo common general knowledge in the field relevant to the present invention as it C existed before the priority date of each claim of this application.
BRIEF DESCRIPTION OF THE DRAWINGS The invention is further described by way of examples with reference to the accompanying drawings in which: Figure 1 is a schematic representation of the method of the invention applied to the tank leaching of sulphide concentrates, and Figure 2 is a schematic representation of the method of the invention as used in a heap leaching operation.
DESCRIPTION OF PREFERRED EMBODIMENTS Figure 1 of the accompanying drawings illustrates the method of the invention as used in a tank leaching operation.
WO 02/081761 PCT/ZA02/00062 4 The drawing illustrates a bioreactor 10, an agitator or mixer 12, an air supply source 14, an air disperser 16 inside the tank of the reactor 10, and a control valve 18 which is used to control the supply of air from the source 14 to the disperser 16.
A carbon dioxide supply source 20 is connected via a control valve 22 to a supply line extending from the valve 18 to the air disperser 16.
Sulphide concentrate is supplied as a slurry from a storage tank 26 to the bioreactor The slurry is diluted with a saline solution drawn from a supply source 28. The saline solution is added directly to the concentrate storage tank 26, as is indicated by means of a dotted line, or alternatively is mixed with the concentrate feed slurry in a supply line 30 to the bioreactor.
Salt tolerant bacteria are inoculated into the bioreactor 10 directly or, as is shown in Figure 1, by introducing the bacteria into the saline solution which is added to the concentrate. Use is made of the bacteria deposited at the German Culture Collection under the respective accession Nos DSM 14175 and DSM 14174 or a salt tolerant strain of Thiobacillus prosperus which is naturally occurring and extracted for example from sea water with a high ferrous iron content and with a reduced pH of between 3 and 4 or a strain of Thiobacillus prosperus which is adapted for the purpose.
The bacterium deposited under accession No. DSM 14175 is Acidihalobacter ferrooxidans and the bacterium deposited under accession No. DSM 14174 is Acidihalobacter aeolicus.
WO 02/081761 PCT/ZAO2/00062 The source 28 also contains nutrients for cell growth. The nutrients may be carbonate minerals and a yeast extract.
The salt content in the saline solution may lie in the range of from 10 000 ppm to 35 000 ppm CI. This depends on the salt tolerance capability of the bacterium or bacteria which are used in the bioleaching operation. Depending on the salt tolerance of the bacteria the salt content may be in excess of 35000 ppm CI.
Cell growth occurs in the bioreactor 10 as concentrate, saline solution and nutrients are supplied to the bioreactor. The bioleaching process can be enhanced by the judicious addition of air and carbon dioxide from the sources 14 and Mineral treatment steps which are carried out prior to the bioleaching phase and subsequently thereto to recover the metal content from the leach solution, are not shown for these aspects are known in the art.
Figure 2 illustrates the method of the invention as applied to the treatment of a mineral sulphide ore in a heap leaching operation.
Figure 2 illustrates a heap 40 of sulphide mineral ore positioned over a plurality of air dispersion pipes 42 which are supplied with air from a source 44.
Heap leaching is effected by irrigation with the saline return solution and nutrients, from storage tanks or ponds 46, using an overhead pipe dispersion arrangement 48.
Pregnant leach solution is collected from the base of the heap and is directed to a pond 50. The solution in the pond is treated (52) to recover dissolved metals and spent WO 02/081761 PCT/ZA02/00062 6 solution 54, devoid of leached metals, is returned to the saline return storage tanks or ponds 46.
The bacterium of an adapted strain of Thiobacillus prosperus which is salt tolerant, as described hereinbefore, is inoculated in the ore which is placed on the heap or into the saline solution which is returned to the heap e.g. into the storage tanks or ponds 46.
The solution which is contained in the tanks or ponds 46 may have a salt content of from 10 000 ppm to 35 000 ppm or more. Nutrients are added to the solution as required for optimising cell growth.
A principal benefit of the invention is that the salt tolerant bacterium or bacteria, described hereinbefore, enable bioleaching to take place in a saline solution containing from 10 000 ppm CIl up to at least 35 000 ppm Cl-. This substantially reduces or even eliminates the need for using fresh water. Consequently bioleaching, either by treatment of mineral sulphide concentrates in stirred reactors, or mineral sulphide ores in heaps, may be undertaken in arid regions where fresh water supplies are limited and only saline water is available for bioleaching.
A further benefit of the invention is that the presence of chloride in the leaching phase may improve metal recovery by enhancing the rate and extent of mineral leaching. For example in chemical leaching the presence of chloride has been shown to enhance the rate and extent of chalcopyrite leaching.
Claims (9)
1. A method of treating a sulphide mineral which includes the step of bioleaching the mineral in a saline solution with a chloride content in c 5 excess of 5000 ppm and at a temperature in excess of 100 C, with at 00oo least one salt tolerant bacterium, wherein the bacterium is selected from c-I c the microorganisms deposited at the German Culture Collection under Sthe respective accession Nos. DSM 14175 and DSM 14174.
2. The method according to claim 1 wherein the chloride content in the solution is in excess of 10000 ppm.
3. The method according to claim 1 or 2, applied in a heap leaching situation, wherein the bioleaching takes place at a temperature in the range of from 10 0 C to 250 C.
4. The method according to claim 3 wherein the bacterium is inoculated in ore which is placed on the heap, or into a saline solution which is used to irrigate the heap.
The method according to claim 1 or 2 applied in a tank leaching situation, wherein the bioleaching takes place at a temperature above 250 C.
6. The method according to claim 5 wherein the bioleaching takes place at a temperature in the range of from 350 C to 450 C.
7. The method according to claim 5 or 6 wherein the tank includes an agitator. 00 C
8. The method according to any one of claims 5, 6 or 7 wherein the Sbacterium is inoculated directly into the tank, or is added to the saline solution.
9. The method according to claim 8 wherein the saline solution is added to, 00 5 or mixed with, a concentrate of the sulphide mineral which is then C(N supplied to the tank. A method of treating a sulphide mineral which includes the step of bioleaching the mineral in a saline solution with a chloride content in excess of 5000 ppm and at a temperature in excess of 100 C, with at least one salt tolerant bacterium, substantially as herein exemplified.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ZA200102943 | 2001-04-10 | ||
| ZA2001/2943 | 2001-04-10 | ||
| PCT/ZA2002/000062 WO2002081761A2 (en) | 2001-04-10 | 2002-04-09 | Bioleaching of a sulphide concentrate in a saline solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU2002254782A1 AU2002254782A1 (en) | 2003-04-10 |
| AU2002254782B2 true AU2002254782B2 (en) | 2008-02-07 |
Family
ID=25589132
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU2002254782A Ceased AU2002254782B2 (en) | 2001-04-10 | 2002-04-09 | Bioleaching of a sulphide concentrate in a saline solution |
Country Status (4)
| Country | Link |
|---|---|
| AR (2) | AR033138A1 (en) |
| AU (1) | AU2002254782B2 (en) |
| PE (1) | PE20021119A1 (en) |
| WO (1) | WO2002081761A2 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008036985A2 (en) * | 2005-09-15 | 2008-03-27 | Bhp Billiton Sa Limited | Bioleaching process control in a stirred tank |
| US8497113B2 (en) | 2006-02-06 | 2013-07-30 | Jx Nippon Mining & Metals Corporation | Chloride ion-resistant sulfur-oxidizing bacteria |
| CL2009001474A1 (en) * | 2008-06-29 | 2009-11-20 | Consolidated Nominees Pty Limited | Procedure to treat sulfurized mineral that includes bioleaching in solution of cl- ions with a consortium of mixed cultures of leptosprillium ferriphilum and sulfur, halophilic or halotolerant oxidizing microorganism, where the solution contains 1500-30000 ppm of cl- and also contains al, mg or na, at> 10 degrees and ph 1-3. |
| CL2014002238A1 (en) * | 2014-08-22 | 2014-10-17 | Compañia Minera Zaldivar Limitada | Leaching of copper sulphides in chloride-ferrous medium with bacteria |
| CN104404252B (en) * | 2014-12-19 | 2016-07-27 | 中南大学 | A kind of method utilizing sea water to carry out Bioleaching sulphide ore |
| WO2024178306A1 (en) | 2023-02-24 | 2024-08-29 | Cemvita Factory, Inc. | Process |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5231018A (en) * | 1990-10-12 | 1993-07-27 | The Israel Electric Corporation, Ltd. | Extraction of metal oxides from coal fly ash by microorganisms and a new microorganism useful therefor |
| CA2063687A1 (en) * | 1992-03-20 | 1993-09-21 | Raphael Fass | Bioleaching method for the extraction of metals from coal fly ash using thiobacillus |
| US5278069A (en) * | 1992-02-14 | 1994-01-11 | The Israel Electric Corporation Ltd. | Bioleaching method for the extraction of metals from coal fly ash using thiobacillus |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DD278574A1 (en) * | 1988-12-27 | 1990-05-09 | Akad Wissenschaften Ddr | PROCESS FOR MICROBIAL REMOVAL OF ORGANIC COMPOUNDS |
| AU661873B2 (en) * | 1991-10-31 | 1995-08-10 | Genencor International, Inc. | Haloalkaliphilic microorganisms |
-
2002
- 2002-04-09 AU AU2002254782A patent/AU2002254782B2/en not_active Ceased
- 2002-04-09 AR ARP020101305A patent/AR033138A1/en active IP Right Grant
- 2002-04-09 WO PCT/ZA2002/000062 patent/WO2002081761A2/en not_active Application Discontinuation
- 2002-04-10 PE PE2002000300A patent/PE20021119A1/en not_active Application Discontinuation
-
2008
- 2008-04-30 AR ARP080101850A patent/AR066378A2/en active IP Right Grant
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5231018A (en) * | 1990-10-12 | 1993-07-27 | The Israel Electric Corporation, Ltd. | Extraction of metal oxides from coal fly ash by microorganisms and a new microorganism useful therefor |
| US5278069A (en) * | 1992-02-14 | 1994-01-11 | The Israel Electric Corporation Ltd. | Bioleaching method for the extraction of metals from coal fly ash using thiobacillus |
| CA2063687A1 (en) * | 1992-03-20 | 1993-09-21 | Raphael Fass | Bioleaching method for the extraction of metals from coal fly ash using thiobacillus |
Non-Patent Citations (1)
| Title |
|---|
| Hydrometallurgy, vol 59, p379-380 & CA2063687 * |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2002081761A3 (en) | 2004-02-12 |
| PE20021119A1 (en) | 2002-12-11 |
| AR033138A1 (en) | 2003-12-03 |
| WO2002081761A2 (en) | 2002-10-17 |
| AR066378A2 (en) | 2009-08-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| TC | Change of applicant's name (sec. 104) |
Owner name: BHP BILLITON SA LIMITED Free format text: FORMER NAME: BILLITON SA LIMITED |
|
| FGA | Letters patent sealed or granted (standard patent) | ||
| MK14 | Patent ceased section 143(a) (annual fees not paid) or expired |