Safety of high-performance breakage faces in methane-producing mines

The experience of degassing coal seams using underground boreholes is summarized, scientifically based schemes and parameters of degassing coal seams and the mined out space with directional boreholes in extended excavation areas of shallow coal mines are proposed. The initial gas-dynamic parameters of the excavation area were determined according to the permissible methane content of the breakage face by the gas factor, the methane content of the coal seam in the zone of its excavation by the combine. The lower limit of the methane-bearing capacity of the mined seam, at which preliminary degassing of the coal mass is necessary, is scientifically justified. The dependences of the natural methane content of coal seams on the depth of their occurrence in the conditions of Kuzbass and Vorkuta coal deposits, the effect of natural degassing of the formation by a breakage face, the determining role of degassing by drilling long directional boreholes along the mined and converged coal seams at the excavation areas of high-performance mines, the use of the provisions of the industrial regulations of the integrated technology of extraction and utilization of mine methane are experimentally established as well as forecasts of the absolute methane content of the stoping area by the sources of methane release during the coal extraction.