Disentangling effects of temperature on microbial community and copper extraction in column bioleaching of low grade copper sulfide

Using indigenous microorganisms in biomining processes assures few ecological distortions and less time consumption for adaptation. However, there is a debate as to whether an indigenous microbial community is more efficient than one composed of microbial strains selected for specific physiological traits. In order to provide thoughtful opinions in such a debate, a cross-comparison of six strains isolated from two different regions: Chambishi Copper Mine (Zambia) and Dexing Copper Mine (China), was conducted. Physiological properties and leaching performancesof Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum in pure and mixed culture were studied. The results showed that strains within species presented similar traits while copper resistance was not species-specific. In terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the exogenous. In addition, microbial community analysis revealed the different mixed culture shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains.

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Analysis of Microbial Community in Heap Bioleaching of Low-Grade Copper Sulfide Ores

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.777.277 ◽

2018 ◽

Vol 777 ◽

pp. 277-281

Author(s):

He Shang ◽

Biao Wu ◽

Jian Kang Wen ◽

Xing Lan Cui

Keyword(s):

Microbial Community ◽

Acidithiobacillus Ferrooxidans ◽

Copper Sulfide ◽

Heterotrophic Bacteria ◽

Low Grade ◽

Sequencing Technology ◽

Leptospirillum Ferriphilum ◽

Acidithiobacillus Caldus ◽

Sulfobacillus Thermosulfidooxidans ◽

Number Of Microorganisms

High-throughput sequencing technology also known as "next generation" sequencing technology, compared with the traditional sequencing method has the characteristics of fast speed, high flux, low cost. In recent years the technology in the detection of microbial diversity has been fully applied. In this study, the microbial community of ore heap in different area and different depth was studied by using this method. The results showed the bio - heap leaching of low - grade secondary copper sulfide ore in Zijinshan from China could effectively recover the copper in the ore. The number of microorganisms in the center was significantly larger than that on the edge of ore heap, and as the depth increases in the heap, the number of microorganisms decreases. The dominant bacteria in the ore heap center was Acidithiobacillus ferrooxidans, in addition there were also some Sulfobacillus thermosulfidooxidans, Ferroplasma cupricumulans, Acidithiobacillus caldus and a small amount of Leptospirillum ferriphilum in the center of the ore heap. Unlike the ore heap center, Sulfobacillus thermosulfidooxidans was the main species on the edge of the ore heap, moreover Acidithiobacillus ferrooxidans, Ferroplasma cupricumulans, Acidithiobacillus caldus and a small amount of Leptospirillum ferriphilum were found on the edge of the ore heap. In addition, some heterotrophic bacteria such as Pseudomonas, Serratia, Sediminibacterium, Stenotrophomonas, Brevundimonas and Variovorax were found both in the center and the edge of the sample, these heterotrophic bacteria may be beneficial for the leaching of valuable metals.

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Changes in the composition of an acid mine drainage microbial community upon successive transfers in medium containing low-grade copper sulfide

Bioresource Technology ◽

10.1016/j.biortech.2011.05.095 ◽

2011 ◽

Vol 102 (20) ◽

pp. 9388-9394 ◽

Cited By ~ 13

Author(s):

Yi Liu ◽

Huaqun Yin ◽

Yili Liang ◽

Li Shen ◽

Yao Liu ◽

...

Keyword(s):

Microbial Community ◽

Acid Mine Drainage ◽

Copper Sulfide ◽

Mine Drainage ◽

Low Grade ◽

Acid Mine

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Distinct Roles of Acidophiles in Complete Oxidation of High-Sulfur Ferric Leach Product of Zinc Sulfide Concentrate

Microorganisms ◽

10.3390/microorganisms8030386 ◽

2020 ◽

Vol 8 (3) ◽

pp. 386 ◽

Cited By ~ 3

Author(s):

Maxim Muravyov ◽

Anna Panyushkina

Keyword(s):

Microbial Community ◽

Zinc Sulfide ◽

Elemental Sulfur ◽

Waste Product ◽

Sulfur Oxidation ◽

Low Grade ◽

Sulfide Concentrates ◽

Sulfide Concentrate ◽

Elemental Sulfur Oxidation ◽

Ferric Leaching

A two-step process, which involved ferric leaching with biologically generated solution and subsequent biooxidation with the microbial community, has been previously proposed for the processing of low-grade zinc sulfide concentrates. In this study, we carried out the process of complete biological oxidation of the product of ferric leaching of the zinc concentrate, which contained 9% of sphalerite, 5% of chalcopyrite, and 29.7% of elemental sulfur. After 21 days of biooxidation at 40 °C, sphalerite and chalcopyrite oxidation reached 99 and 69%, respectively, while the level of elemental sulfur oxidation was 97%. The biooxidation residue could be considered a waste product that is inert under aerobic conditions. The results of this study showed that zinc sulfide concentrate processing using a two-step treatment is efficient and promising. The microbial community, which developed during biooxidation, was dominated by Acidithiobacillus caldus, Leptospirillum ferriphilum, Ferroplasma acidiphilum, Sulfobacillus thermotolerans, S. thermosulfidooxidans, and Cuniculiplasma sp. At the same time, F. acidiphilum and A. caldus played crucial roles in the oxidation of sulfide minerals and elemental sulfur, respectively. The addition of L. ferriphilum to A. caldus during biooxidation of the ferric leach product proved to inhibit elemental sulfur oxidation.

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