Chersky Institute of Mining of the North, Yakutsk, Russia:

V. P. Zubkov, Deputy Director of Scientifi c Work, Candidate of Engineering Sciences
G. P. Neobutov, Senior Researcher, Candidate of Engineering Sciences
D. N. Petrov, Researcher, Candidate of Engineering Sciences, petrovdn74@mail.ru

The analyses and generalization of the experience gained in underground gold mining in the Republic of Sakha (Yakutia) show that the application of modifications of mining systems with shrinkage, rooms and pillars and longwalls often results in high loss and dilution, which calls for the introduction of resource-saving technologies. In mining steeply dipping ore bodies, when mining front reaches subpermafrost levels, it is recommended to enhance mine performance using shrinkage stoping with flexible separating canopy. The article reports the data on physical simulation of ore discharge, which illustrate that application of guide members enables 2 times reduction in ore loss as compared with the ore discharge without the canopy. Developed at the Institute of Mining of the North, SB RAS, the proposed engineering solutions are aimed at elimination of the problem connected with the canopy control during ore discharge and to enhance mining efficiency in the roof rocks of a production block. For the underground mining of precious minerals in the zone of permafrost, the room-and-pillar system designed and commercially introduced at Badran deposit uses ice-and-waste rock backfill, which has allowed reduction in ore loss and dilution down to 0–3 and 17–21%, respectively. The basic flow diagram of mining with the ground control in the permafrost rock mass using layer-bylayer freezing of water-and-rock backfill mixtures in Badran mine is presented. Based on the package of theoretical and experimental studies carried out at the Institute and considering the many year’s experience gained in application of the described technology at Badran deposit, the recommendations on backfilling design and technology have been developed, which allows essential cutting in time of backfilling and enhances efficiency and safety of mining. The use of the engineering solutions and recommendations proposed by the Institute of Mining of the North, SB RAS, with regard to underground mining conditions in the zone of permafrost and subpermafrost levels will enable appreciable gain in completeness and quality of extraction of mineral reserves in the Extreme North without signifi cant rise in cost of the operations, which will ensure efficient mineral mining in the remote areas under conditions of lack of an infrastructure and expensiveness of man power, energy and materials.

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