Transbaikal State University, Chita, Russia:

V. V. Medvedev, Head of Chair, Candidate of Engineering Sciences, medvedevvv1963@mail.ru
A. M. Zozulya, Post-Graduate Student

Priargunsky Mining and Chemical Works, Krasnokamensk, Russia:
S. G. Gurov, Chief Engineer of Mine No. 8

According to experts’ forecasts, exhaustion of active raw material supplies base at Priargunsky Mining and Chemical Works (Priargunsky) will result in depletion of mineral reserves in affiliated operating mines in the nearest 5–10 years. Prospects for maintenance of Priargunsky production capacity include construction of Mine No. 6 as well as introduction of new geotechnologies for mining and processing of poor commercial and noncommercial reserves. Heap leaching of poor ore after X-ray radiometric grading of ore and rocks lifted to the ground surface and in refuse heaps becomes a sufficiently effective method. Uranium recovery by heap leaching reaches 75% at the present day. With introduction of underground leaching of poor commercial and noncommercial ore blocks, it is expected that production output increases by 10–30% at cost reduction by 10%. Practice of underground block leaching shows that loss of strategic material should be prevented at the stage of block preparation. Improvement of preparation process should be carried out in two directions: selection of rational mining scheme and optimization of drilling-and-blasting design. Furthermore, an important task is to deal with mechanical mudding in shrinkage ore block during leaching. To this effect, it is proposed to use air-impact treatment of sites prone to caking. For preparation of gently dipping thin ore bodies, the mining system with section-by-section shrinkage is put forward, which eliminates repacking of ore after large-scale blasting. Thus, implementation of the proposed package of measures can create conditions for the increase in the useful component recovery to 70–75%.

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