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Abstract Aiming at the problems of poor gas drainage effect, high drainage cost, and long drainage time in high gas and low permeability coal seams, the gas drainage fracturing and anti-reflection technology was applied in Zhangcun Mine to strengthen the gas drainage effect of coal seams. The field test analyzed the changes of the basic parameters of the pores and fissures of coal samples before and after fracturing, and clarifies the mechanism of antireflection enhancement. The results showed that ① the pore volume and specific surface area of ??gas fracturing coal seams were dominated by large pores; ② under different adsorption equilibrium pressures and particle sizes, there was a difference in the decrease in the diffusion coefficient of fracturing coal seams with time ③After gas fracturing, the basic parameters of coal seam pores and fissures all showed an increasing trend, which was conducive to shortening the gas diffusion path and increasing the gas diffusion coefficient; ④ after gas fracturing, the effective extraction radius of the borehole, the coal seam permeability coefficient and permeability, were increased by 2.1 to 4.3 times, 54 to 96 times and 7.54 to 30.4 times respectively. Thus, it was determined that the fractured coal seam was transformed from the original difficult-to-drain coal seam to the easily-drainable coal seam.
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