Research on gas extraction technology of borehole instead of roadway

In order to solve the gas problem in the upper corner of 12214 working face in Xinyuan Coal Mine, the roof lithology of the working face, the range of roof fissure zone and its influence on gas flow and accumulation in goaf were investigated. The source of gas emission was analyzed and a group of 7 high-level directional long boreholes in different strata were determined. These were to compare the pumping effect with that of the first high drainage roadway. The results show that after five months of mining observation, the average gas concentration of high-level directional long borehole group and high drainage roadway is 17.24% and 21.32% respectively. The amount of pure gas extraction is 3.71 m³/min and 3.37 m³/min, respectively. The average gas concentration in the upper corner is 0.42% and 0.49% respectively. The results show that the influence range of high-level directional long borehole in roof is wider than that of high drainage roadway. The pure gas extraction increased by 10.09%. The construction cost is lower than the high drainage roadway, and the construction efficiency is higher. It greatly alleviates the restriction of high drainage roadway driving speed on coal face putting into production, thus proving that the high-level directional long borehole in the roof can effectively replace the high drainage roadway.