Research on key technologies for precise drilling and extraction of pressure relief gas in extra-thick coal seams
Aiming at the problem of gas prevention and control in close range coal seam group mining in a coal mine,the key technology of accurate extraction by directional drilling with pressure relief gas in extra-thick and hard coal seam was studied,the technical parame-ters of directional long drilling for pressure relief gas extraction in protruding coal seams were optimized,and the enrichment area of high concentration gas in goaf after pressure relief was determined.According to the mining sequence of the coal seam group,a joint three-dimensional gas extraction system of directional high-level long drilling,common drilling and surface drilling in coal seam group was es-tablished to ensure the safe mining of each coal seam in coal seam group.
close range coal seam groupgas prevention and controlprotective layer miningdirectional drillingthree-dimensional ex-traction
万方数据
维普
