Дегазация сближенных угольных пластов направленной трассы скважинами

Abstract

The technology of conducting degassing operations at the mines of Russia is determined by the experience of many years of using means of extracting methane from coal seams and worked-out spaces by drilling wells on coal seams under development, on converged layers, mainly under-worked, unloaded by a working face from rock pressure. The parameters of the degassing of methane release sources at the extraction areas of coal mines were determined based on the results of scientific studies of the processes of methane release into degassing wells and mine workings, methane content of coal seams, gas content of workings, extraction modes of captive methane-air mixtures, their gas composition, suitability for disposal. The dependences were established related to the methane content of coal seams on the yield of volatile substances, gas recovery indicators, and the rate of reduction of methane release during the operation of wells drilled in the plane of the coal seam at high-performance coal mines. The analysis of the results of the operation of coal mines in Russia was carried out, where the degree of methane extraction based on degassing and gas suction at mining sites was 760 m3/min or 54 % of all methane at 193 exploited sites. In 30 areas where degassing was used, this figure reached 1050 m3/min (75 % of the total). At the same time, the flow rate of captured methane was 365 m3/min, including 237 m3/min (60 %) at 6 mines. Studies of degassing parameters of the converged coal seams were carried out in mining areas where the development workings are separated from the mined-out space of the entire coal. In areas of mining operations with high methane release from undermined coal seams, a complex of underground degassing schemes was applied using long directional wells drilled from a local working with its horizontal part brought into the plane of the adjacent seam. The technology, performance and parameters of degassing are determined taking into account the mining conditions of occurrence and mining of coal seams, and the provisions of the regulatory instructions.