Research on optimization of drill hole gas pre-drainage process in low permeability outburst coal seam

Abstract

To study the drill hole gas pre-drainage technology in low-permeability outburst coal seam, this paper selects the 1031 working face of the first coal seam in the Songhe Coal Mine as the research and test area, adopts Ansys numerical simulation software for the simulated calculation of different drill hole spacing and different drainage time, different drainage effects are obtained, and the test results show that: when the hole spacing is 2.0 m, the drainage result is the best, the residual gas content in the coal seam of the working face drops to less than 5.92 m3/t, and the residual gas pressure drops to less than 0.58 MPa, the gas drainage rate is increased to 61.48%, and the outburst risk is also reduced. This optimization method has a guiding significance for the gas drainage and utilization of other low-permeability outburst coal seams.