Gas Extraction Drilling Sealing Technology for Mining Seam Based on PD Sealing Material

To improve gas extraction drilling sealing technique of mining seam for low permeability and high gassy single coal, PD sealing material technology is developed, and its engineering experiment is done in the 2101 working face of Changcun Coal Mine. The application results show that the PD material sealing technology is obvious, and its sealing effect increase exponentially than ordinary sealing method under the same conditions. Gas extraction concentration increases from 9.6% to 36.5%, and gas extraction flow increases from 0.026 m³/min to 0.077 m³/min.