Coalbed methane is undergoing vast challenges in the exploration and production process, especially the degasification in low permeability of coal seams with the highest gas concentrations. Enhancing the permeability of soft coal seam should be emphasized. In present work, the field tests on presplitting and blasting technology with deep boreholes have been conducted, besides the permeability variations, including the gas extraction concentration and purity of low permeability coal seam, have

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... en obtained by means of field experiments. Research results have shown that the permeability improved by presplitting and blasting with deep boreholes is 2.5 times higher than that of the original coal seam. Research results promote the prevention and control of coal-gas outburst in low permeability and high gas concentration coal seams.