Investigation and Application on the Effect of Pressure Relived and Permeability Enhanced of Ultra-high Pressure Hydraulic Slotting in Lvtang Coal Mine

In order to effectively solve the problem of low tunneling efficiency of coal roadway in low permeability outburst coal seam in Lvtang Coal Mine, which caused by excessive regional verification index and gas exceeding the limit in tunneling area, the ultra-high pressure hydraulic slotting technology to release the pressure and enhance the permeability was tested and applied in the 6th S204 return airway of the coal roadway, and the reasonable fracturing pressure, cutting radius, gas extraction purity and other parameters of the coal seam have been determined. The results show that the ultra-high pressure hydraulic slotting technology can effectively enhance the permeability of coal seam, greatly improve the efficiency of gas extraction, and the progress of coal roadway tunneling increases to 87.5 m/month, which is from 20.0 m/month to 30.0 m/month before. It solves the difficulties of gas control in coal roadway excavation of low permeability and outburst coal seam, and provides experience and technical guidance for efficient gas governance of coal roadway in similar mining areas.