Downloaded 217 times
Uploaded byNishanth S
Biomining
This document discusses biomining, which is the use of microorganisms to extract and recover metals from ores. Traditional mining involves excavation, crushing, and smelting, but produces dust, gases, and toxic compounds. Biomining is a more environmentally friendly alternative that uses microbes and their enzymes to oxidize and dissolve metals from ores. Copper was the first metal extracted using microbes in Rio Tinto mines in Spain in 1752. Common microbes used in biomining include Thiobacillus ferrooxidans and Thermothrix thioxidans. Factors that affect biomining include temperature, acidity, aeration, particle size, and ore composition. Main types of biomin
More Related Content
Biomining
- 1.
- 2. Introduction Traditional ways ofmining: Excavation Crushing Smelting Extraction of Fe, Cu & Au Why Biomining? Dust Gases Toxic compounds 1. Cheap 2. Reliable 3. Efficient 4. Safe 5. Environmentally friendly
- 3. The use ofmicro-organisms to facilitate the extraction and recovery of precious and base metals from primary ores and concentrates, referred to generically as ‘biomining’, has developed into successful and expanding area of biotechnology. Simply, 1. Extracting mineral ores 2. Enhancing the mineral recovery Copper - first metal extracted using microorganisms Rio Tinto mines in Spain 1752. Biomining Rawlings & Johnson (2007) Rossi (1990)
- 4. BIOLEACHING / BIO-OXIDATION Howthis could be possible!!! Extraction of metals Removal of constituents Mediated by microbial enzymes Metabolite formed by the MO’s Oxidases/Reductases Organic / Inorganic acids
- 5. Biomining Recovery DIRECT INDIRECT T.ferroxidans & T. thioxidans Desulfovibro desulfuricans
- 6. Characteristics of organisms Processinvolved Character 1. Production of high temperatures THERMOPHILIC 2. Strong acids and alkalis CHEMOPHILIC 3. Produce energy from inorganic compounds AUTOTROPHIC 4. Attachment BIOFILMS Examples: Thiobacillus ferrooxidans - Chemophilic, Moderately thermophilic, Produce energy from oxidation of inorganic compounds like sulfur and iron. Thermothrix thiopara - extremely thermophilic 60-75C - extraction of sulfur Sulfolobus acidocaldarius S. brierleyi
- 7. Factors affecting biomining Crystallattice energy Surface Area High temperature Acid concentrations High concentration of heavy metals Mechanical stability Degree of solubility CL inversely proportional to solubility Smaller the size higher the recovery Concentration of sulphides Amount of mineral content Extent of contamination Ore composition Choice of bacteria
- 8. Factors affecting biomining TemperatureAcidity Aeration Solid-Liquidratio Surfactants pH 2.5 – 5.3 Mesophilic / Thermophilic 25-35C Aerobic
- 9. Stirred Tank Biomining Bioheaps In–situ biomining Types of Biomining
- 10. Stirred tank biomining Leachingfrom substrates with high mineral concentration Types of Biomining Expensive Time consuming Copper and refractory gold ores Thiobacillus is commonly used
- 11. Bioheaps CRUSHING Acid treatment Agglomeration Water treatment Breakdowninto small particles Growth & multiplication of chemophilic bacteria Finner particles attached to the coarse ones Optimization of moisture content Height: 2- 10 feet with altering tubes for air supply biopiles/ biomounds/ biocells
- 12. Biomining of Copper COPPERORE Water & Sulphuric acid trt Leach solution Lead/Graphite Cu C A Aluminium - + Cu Cu Cu Cu Cu Cu Cu Cu CuCu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Cu Organic extractant Highly acidic electrolyte Leach solution Electrowinning
- 13. 1. http://biologywriteup.blogspot.in/2014/10/biomining-use-of- microbes-biomining.html 2. Agate,A D. 1996. Recent Advances in Microbial mining. World Journal of Microbiology & Biotechnology 12: 497-495 3. Rawlings, D.E, Johnson,D.B. 2007. The microbiology of biomining: development and optimization of mineral-oxidizing microbial consortia. Microbiology,153: 315–324 References