In order to reduce the gas emission from the goaf of the coal mining face and the gas content at the upper corner of the coal mining face, a theoretical analysis was conducted on the roof crack variation and the gas flow law of the goaf. Based on the circumstance, a comprehensive gas drainage control method with the separated gas resources, including the gas drainage with the buried pipeline at the upper corner and the gas drainage with boreholes drilled at the high level drilling site for the roof cracks was provided for the gas drainage of No. 21141 coal mining face in Zhujiao Mine. The application results showed that the application of the drainage technology with separated gas resources could make the gas volume fraction at the upper corner of No. 21141 coal mining face reduced from the previous 0. 6% to 0.4%. The gas drainage volume fraction of a single borehole at the high level drilling site was 34% in average and the gas flow was 0. 062 m3/min. Thus the gas emission from the goaf was reduced and the safety production of the coal mining face could be ensured.%为降低回采工作面采空区的瓦斯涌出及上隅角瓦斯浓度,对采空区顶板裂隙变化及瓦斯流动规律进行了理论分析,基于此,对主焦煤矿21141工作面的瓦斯抽放提出了分源抽放的综合治理方法,即上隅角采用埋管抽放,顶板裂隙内瓦斯采用高位钻场钻孔抽放.应用结果表明:分源抽放技术的应用使得21141回采工作面上隅角瓦斯体积分数由原来的0.6%左右下降到0.4%,高位钻场单孔瓦斯抽放体积分数平均为34%,瓦斯流量为0.062 m3/min,这在一定程度上降低了采空区瓦斯的涌出量,保证了工作面安全生产.
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