E. P. Slavsky PIMCU, Krasnokamensk, Russia:

A. V. Beidin, Director of Central Research Laboratory, Candidate of Engineering Sciences, BeidinAV@ppgho.ru
A. A. Morozov, Director of Science, Doctor of Engineering Sciences

Transbaikal State University, Chita, Russia:
A. A. Yakimov, Head of department, Associate Professor, Candidate of Engineering Sciences

The promising trends in improvement of geotechnical methods of low-grade and noncommercial mineral production are discussed. The results of the chemical, material and granulometric analyses of uranium-containing aluminosilicate ore are presented. In the selected technological samples, the content of uranium was determined as function of the size with a view to setting fractional compositions for heap and in-situ leaching. At a laboratory scale, kinetics of percolation leaching of uranium was studied on a feedstock formed by the criteria of fineness and useful component content. The obtained results prove that the key factor to influence uranium recovery is the content of metal in the stock. For another thing, uranium recovery grows as the time of leaching increases. The maximum extraction of uranium in pregnant solution is achieved in leaching of high-grade ore. On the other hand, in view of the duration of the process and low recovery ratio of metal as compared with hydrometallurgy, processing of such ores using geotechnical approaches is economically inexpedient. Furthermore, the leaching efficiency essentially depends on such factors as the type of ore-hosting rocks, consumption of a leach agent and its content in process solutions, mass ratio of solid and liquid phases, as well as the mode and intensity of ore sprinkling. The optimal production data which have influence on leaching efficiency are given (consumption of a leach agent and its content in process solutions, mass ratio of solid and liquid phases, spray rate). The duration of uranium extraction to pregnant solution is correlated with the uranium content in samples of different composition (chemical, material, fractional) and with the metal content of ore. The influence of surface-active substances on the production data of leaching is determined.

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