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The lack of new deposits with a rich copper content and the depletion of old deposits, as well as the need to comply with environmental requirements, raises the issue of the need to process the tailings of metallurgical industries. In Kazakhstan was accumulated significant stocks of tailings "Borgezsay" and "Staroye". The tailings reserves are estimated at up to 1 billion tons. Sample evaluation showed that the average copper content in the tailings is 0.15-0.2%. More than 1 million tons of copper are stored in th...

Technology of in-situ recovery (ISR) of uranium is using in Kazakhstan for increasing of production 15 times from 800 ton in 1998 till 22 000 ton in 2013. This ISR process is zero wastes technology. Investigations showed serious potential to improve results of ISR technology using biotechnology methods. Uranium in the ore body is usually presented as hexavalent (soluble) and tetravalent uranium (slightly soluble). To convert uranium into a soluble form, it is necessary to oxidize tetravalent uranium. Leaching solu...

Studies aimed at improving the efficiency of the field preparation of hydrogen sulfide and mercaptan-containing oil are especially relevant in connection with the tightening of regulatory requirements for quality and safety indicators of commercial oil. The Technical Regulation (TR) of the Eurasian Economic Union TR 045/2017 -On the safety of oil prepared for transportation and (or) use- establishes uniform requirements for the safety indicators of oil delivered through trunk pipelines, as well as used as a raw ma...

At the Azgir nuclear test site in Western Kazakhstan 17 nuclear explosions were carried out at a depth of 165 to 1500 m, as well as ground explosions. Nine underground cavities with a total volume of about 1.2 million m3 with extremely high residual radioactivity were formed in the thickness of the rock salt layers. Five of the nine cavities are filled with groundwater and strontium, cesium and plutonium radionuclides are leaking into the environment, and radionuclides spread through food chains. A medical examina...

At one of the Kazakh uranium deposits, studies were carried out on the effect of ironoxidizing bacteria on the redox potential of leaching solutions. The studies carried out on three bioreactors with a volume of 1 m3 and one bioreactor with volume 6 m3 made it possible to establish a close relationship between the content of ferric iron in the solution and the redox potential of the leaching solution. In situ recovery of uranium uses sulfuric acid leaching solutions containing sulfuric acid from 3.5 g/liter to 25 ...

Uranium in situ recovery (ISR) is an effective method for extracting uranium from sandstone deposits. Many uranium deposits are characterized by the presence of associated metals: gold, platinum group metals and rare earth metals. For one of the uranium deposits in Kazakhstan, studies were carried out on sampling from productive wells at the ISR of uranium. An analysis was carried out for the content of uranium, rare earth elements, scandium, germanium, yttrium and other metals. For the study, samples were taken f...

Uranium mining companies of Kazakhstan during 15 years increased production of uranium more than 15 times using in-situ recovery of uranium (ISR). At the same time a significant part of uranium deposits contains gold, silver, palladium and rare metals like rhenium, germanium, scandium and et`s. The task was set for the complex extraction of associated metals from technological solutions of a uranium mine. Work was carried out to select and study samples of productive solutions and leaching solutions at one of the ...

Metal?microbe redox interactions have implications for ore formation and recovery of uranium from ore-containing materials. The speciation of uranium in relation to its bio-availability is reviewed. U(VI) is the major form of U in oxic surface waters, while U(IV) - in anoxic waters. The ability of uranium to bind the bacterial cell surface is dependent on its physicochemical form. Within solid-phase organic matter, microbes can influence oxidation state and stability of uranium through direct enzymatic reduction, ...