JSC VNIPIpromtekhnologii, Moscow, Russia

A.V. Gladyshev, General Manager

National Research Nuclear University MEPhI, Moscow, Russia
М. D. Noskov, Head of Departmant, Doctor of Sciences in Physics and Mathematics, Professor, e-mail: MDNoskov@mephi.ru

JSC Atomredmetzoloto, Moscow, Russia
I. N. Solodov, Program Director of Innovation and Technological Development, Doctor of Geological and Mineralogical Sciences

JSC Khiagda, Chita, Russia
А. V. Suvorov, Chief Geologist

Using the in-situ borehole leaching (ISL) method, it is possible to extract uranium deposits characterized by complex hydrogeological and mining-technological conditions. Mining of the production block using the ISL method includes three stages: acidification of the ore deposit, active leaching and completion. Due to various natural and technological factors areas with a high content of residual or redeposited uranium are formed during the mining process, called remains or pillars. The formation of remains leads to a decrease in the rate of uranium production and a decrease in the degree of reserve development. An important task for increasing the efficiency of ISL is to intensify the extraction of uranium from the remains. The paper considers the use of a geotechnological information modeling system to determine possible areas of remains formation and find ways to involve them in mining. The operation of the system is based on a mathematical model that describes pressure distribution, filtration of solutions, hydrodynamic dispersion, dissolution precipitation of uranium-containing, acid-absorbing and reducing minerals, sorption, complexation, homogeneous and heterogeneous redox processes. The application of geotechnical modeling includes the following stages: creating models of the productive horizon and technological objects; determination of parameters of physical and chemical processes; modeling of technological block development; identification of areas where leaching was not effective enough and remains formed; preparation of proposals for intensifying the extraction of uranium from the remains and carrying out multivariate geotechnological calculations; analysis of the results of multivariate calculations and selection of the best option for finalizing the block. It is advisable to verify the modeling results using control drilling and direct determination of uranium at the ore location using instantaneous fission neutron logging (IFNL).
A.G. Kesler, a researcher of the National Research Nuclear University MEPhI, was actively involved in the work.

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