Estimation of the state-of-the art and substantiation of the choice of efficient explosives and feasible technologies of blasthole and borehole charging at underground mines of PPGKhO OAO
For the perfection of the drilling and blasting system at ore mines of the Priargunsky Industrial Mining and Chemical Works (PPGKhO) the analysis of the explosives range and compositions of fabricated and in-situ prepared explosives used in underground mining operations, and comparative estimates of these products in terms of the main physical, technical and cost characteristics have been made. Supplementary reserves for the enhancement of safety and efficiency of granular explosives application are discussed. Estimates have been made of the prospects of emulsion explosives application in terms of safety and engineering feasibility, mechanized blasting opportunities and regulation of explosives energy characteristics in the process of charging, compliance of sanitary and hygiene requirements in stopes, with due account for the current factors holding off the application of emulsion technologies in underground mines. An overview is presented of equipment for mechanized blasthole and boreholes charging in underground conditions. A comparative analysis is given of the main performance and economic indices (PEI) of pilot blasts with the use of approved cartridge explosives, proprietary granular compositions and estimated forecast characteristics of bulk emulsion explosive compositions, as well as a comparative analysis of performance and economics of full-scale tests of technologies of blasthole pneumatic and manual charging with proprietary granular explosives in development headings at an ore mine run by the PPGKhO. A conception has been elaborated of the drilling and blasting system (DBS) modernization at PPGKhO operating underground mines, as well as feasibility of drilling and blasting technologies and choice of explosives for a planned mine has been grounded, with due account for geological conditions, strength, drillability, blastability of ore and enclosing rock, ore body occurrence characteristics, mining methods applied at mines run by the PPGKhO, results of the comprehensive analysis of the choice of explosives for underground mines and equipment for explosives in-situ fabrication and charging. The conclusion has been made on the feasibility of mechanical blasthole charging with proprietary granular and emulsion explosive compositions.