厚煤层综采放顶回采工作面割煤、放煤期间涌出大量瓦斯,容易造成工作面回风隅角及回风流中瓦斯超限,严重威胁着煤矿的安全生产。为降低红岭煤矿1703采煤工作面回风隅角瓦斯涌出量,分析研究了厚煤层采煤工作面瓦斯涌出规律,提出采煤工作面瓦斯流动“回采工作面下顺槽—回采工作面—回采工作面上顺槽”矩形通道和“回采工作面下顺槽—回采工作面采空区—回采工作面上顺槽”矩形通道“双矩形”通道。基于瓦斯扩散—渗流理论及经验公式,确定了1703采煤工作面高位定向长钻孔瓦斯抽采范围并设计施工了4个高位定向长钻孔,平均日抽瓦斯纯量可达1630m3,工作面生产期间回风隅角最大瓦斯浓度为0.26%,实现了工作面安全高效回采。

During the process of coal cutting and coal releasing in fully mechanized top coal caving stoping working faces of thick coal seams, a large amount of gas is emitted, which can easily cause gas exceeding the limit in the return air corner and return air flow of the working face, seriously threatening the safety production of coal mines. In order to reduce the gas emission quantity from the return air corner of the 1703 coal mining working face in Hongling Coal Mine, the gas emission law of thick coal seam coal mining working face is analyzed and studied. A rectangular channel of "lower crossheading of the stoping working face - stoping working face - upper crossheading of the stoping working face" and a double rectangular channel of "lower crossheading of the stoping working face - goaf of the stoping working face - upper crossheading of the stoping working face" are proposed for the gas flow in the coal mining working face. Based on the theory of gas diffusion-seepage and empirical formulas, the gas extraction range of high position directional long boreholes in the 1703 coal mining working face is determined, and four high position directional long boreholes are designed and constructed. The average daily gas extraction pure quantity can reach 1630 m, and the maximum gas concentration in the return air corner during the production period of the working face is 0.26%, achieving safe and efficient stoping in the working face.