Gas control technology for high gassy sandstone direct overlying working face during initial mining period

Abstract

During the initial mining period of the high gassy and sandstone direct overburden face, the working face is faced with not only the large area roof suspension, but also the problem of gas transfinite caused by the sudden roof caving. Deep hole pre-splitting blasting technology is adopted to blast the roof. the practice shows that the main roof collapses completely when the working face advancing 37m, and large area roof suspension is eliminated during the initial mining period. Gas control roadway is constructed at the rear of open-off cut, perforating drilling, bedding drilling and roof drilling are respectively arranged in the roadway, and the pressure relief gas is pumped from the coal seam and its adjacent seam. This technology has increased the daily output of the working face by 33%, and good results have been achieved in the field practice.