Practice on Comprehensive Gas Drainage Technology in High Gassy Mine

According to the status of a high gas emission value and high gas content at the upper corner in No.1263 coal mining face of Zhaozhuang Mine,a comprehensive gas drainage method combined with gas pre-drainage in mining seam,gas drainage with high level borehole and pipeline buried in goaf was applied in No.12 seam.With the gas pre-drainage in mining seam,the gas drainage value increased by 0.46-1.02 times than conventional borehole layout.After gas drainage with high level borehole conducted,the gas relative emission value of the adjacent seams reduced from 4.38-10.17 m3/t to 1.46-3.16 m3/t.The gas drainage with pipeline buried in goaf ensured the gas volume fraction in the mining goaf kept at 0.7%-0.9% and controlled the gas volume fraction below 1.0% stipulated in Mine Safety Regulations.