Gas Control Technoloy of Coal Mining Face in Contiguous Protective Seam

A study was conducted on the gas emission law of No.5767 coal mining face in a protective seam of Wulan Mine .According to the conditions of No.7 sea m and the below seam No.8 seam, the comprehensive gas control method was provided, including the gas drainage with boreholes drilling along the mining seam, the g as drainage with high upward inclined boreholes in the air returning gateway, the pressure releasing and gas drainage with the surface drilling, the buried pipeline gas d rainage in the mining goaf, the gas drainage with boreholes dilling through the mining seam.An investigation was conducted in the gas control effect.The results showe d that with the comprehensive gas contral measures conducted, the gas content over limite problem during the mining period of No.5767 coal mining face was effectivel y solved.The ventilation quantity of the coal mining face was reduced from previous 1 700 m3/min to 700 m3/min, the gas volume fraction in the air retuning flow was 0. . 32%0.60% and the safety mining of the coal mining face could be ensured.