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The temperature makes considerable impact on gold-bearing minerals decomposition. So, by the Russian scientists on an example of May deposit concentrate it has been shown that the increase in temperature of a pulp to 34 - 36°C intensifies oxidation of gold-bearing mineral - arsenopyrite: after the lapse of 48 hours oxidation degree arsenopyrite reached 95%. On the basis of studying kinetics biooxidation of sulphidic minerals by microorganisms association at various temperature modes in some research institutes of Russian Academy of Sciences has been developed two stage biooxidation technologies by microorganisms association, including moderate-thermophilic bacteria, with flexible regulation of a temperature mode. Also the temperature influences association structure. At temperature from 28°C to 40°C the active association of microorganisms consisting from strains of four bacteria strains - Acidithiobacillus, Leptospirillum, Ferroplasma and Sulfobacillus is formed. At temperature 45°C - the association of microorganisms including strains of two bacteria strains - Ferroplasma and Sulfobacillus. At temperature from above 45°C - only strains of moderate - thermophilic and thermophilic bacteria [1-7]. [ABSTRACT FROM AUTHOR]

New efficient ways of processing mineral raw materials are one of the determinants of scientific and technological progress. In recent years, there has been a tendency to reduce the metal content and complicate the mineral composition of processed ore raw materials, and increase requirements for environmental protection. All this leads to a rise in the cost of mining and extraction of useful components. The ever-growing demand for metals leads to the need to use poor ore, deposits lying at great depths, dumps of mining enterprises [1-8]. Kazakhstan is the largest raw material base for uranium mining in the world, therefore the study of the role of microorganisms carrying out the oxidation of sulphide minerals is very relevant. This chapter presents material on the qualitative and quantitative composition of microorganisms in the heap leaching of off-balance ores [8-15]. [ABSTRACT FROM AUTHOR]