Abstract:
Suffered from the complex working conditions caused by deep mining, there are still great challenges in the efficient gas control and outburst prevention of outburst prone coal seams with high stress and low permeability. In this paper, Xuehu Coal Mine in Henan Province was selected as the engineering background. The enhancement antireflection technology with hydraulic fracturing with dynamic pressure and hydraulic flushing was constructed. The time-sharing interventional dynamic sealing method of drainage boreholes was proposed. The test results show that compared with hydraulic fracturing technology with dynamic pressure for antireflection, using the antireflection technology with hydraulic fracturing with dynamic pressure and hydraulic flushing, the effective drainage radius is increased by nearly one time. The gas drainage net amount of single borehole increased by 3.5 times on average. Using time-sharing interventional dynamic sealing technology with non-solidified slurry, the gas drainage concentration of single borehole has been greatly increased and can be stable at about 30% for a long time. The research results realize the efficient and long-term gas extraction of outburst prone coal seams with high stress and low permeability, which effectively ensure the safe and efficient production of the coal mine. It provides a reference for the development of precise outburst prevention theories and technologies in deep coal seams with high outburst risks.