关键词: 水力压裂, 煤层增透, 瓦斯治理, 巷道掘进

Abstract: Restricted by many factors such as coal seam occurrence conditions and dense roof and floor strata，the 4# coal seam mined in Wangjialing Coal Mine has the characteristics of high gas content， low coal seam and poor permeability. The drilling gas extraction efficiency is low，the attenuation speed is fast，and the gas extraction standard period is long. Therefore，taking the 18109 working face of Wangjialing Coal Mine as the research object，in order to improve the gas extraction efficiency of the working face trans‐ portation channel，it is proposed to use the hydraulic fracturing technology to pre-crack the area and then extract. The numerical simulation study is used to determine that the effective fracturing radius of 4# coal seam is 4.1 m under the water pressure of 20 MPa for 25 min. Based on the numerical simulation results，the fracturing measures are formulated and the effect is investigated. The results show that the attenuation rate of gas extraction concentration in 4# coal seam is 25% after 60 days of fracturing，and the extraction standard period is shortened to 7 days，and the fracturing effect is remarkable. Comprehensive analysis shows that hy‐ draulic fracturing technology can effectively improve the permeability of coal seam and improve the extrac‐ tion efficiency，which has certain positive benefits for gas extraction in low permeability coal seam.

Key words: hydraulic fracturing, coal seam increased permeability, gas control, roadway excavation