高瓦斯特厚煤层高抽巷瓦斯抽采关键参数优化

下沟煤矿4301综放工作面布置在高瓦斯特厚煤层中，工作面瓦斯涌出量大，利用高抽巷瓦斯抽采技术在解决这一难题时会受到诸多参数影响，其中高抽巷与回风巷间的平距、与煤层顶板的垂距是最关键的参数。为寻求关键参数的最优值，以采动覆岩破坏规律为基础，利用FLUENT数值计算方法，模拟高抽巷的平距和垂距对采空区瓦斯抽采效果的影响，综合分析模拟结果和现场实测数据后对参数进行了优化。结果表明：当平距为20 m、垂距为30 m时，高抽巷抽采效果最佳；4301综放工作面高抽巷按最佳参数布置后，高抽巷瓦斯抽采纯流量平均为43.93 m³/min，最高可达54.75 m³/min，占瓦斯涌出总量的75.6%，风排瓦斯量则由原来的14.03 m³/min降至3.91 m³/min，瓦斯抽采效果显著。

The Key Parameters Optimization of High Level Gas Drainage Roadway in Extra Thick and High-gas Coal Seams

The gas emission of 4301 fully mechanized working face in Xiagou Coal Mine in extra thick and high-gas seam is large,and gas drainage technology in high level gas drainage roadway is affected by many factors when solving this problem,there are two most critical parameters,namely the horizontal distance between the high level gas drainage roadway and the return air roadway,the vertical distance between the roof of the coal seam.In order to seek the optimal values of the key parameters,based on the law of overburden rock mass failure properties in mining,using the method of FLUENT numerical calculation to simulate the influence of the vertical distance and the horizontal distance on the drainage effects,obtaining the optimized parameters after comprehensive analysis of simulation results and field data.The results show that when the horizontal distance is 20 m and the vertical distance is 30 m,the effect of gas drainage in high level gas drainage roadway is the best;after the high level gas drainage roadway in 4301 fully mechanized working face arranged by the optimal value,the average gas extraction in high level gas drainage roadway is 43.93 m³/min,its maximum can reach 54.75 m³/min,accounts for about 75.6% of the total gas emission,the amount of air exhaust from the original 14.03 m³/min drops to 3.91 m³/min,these data prove that the gas extraction effect is significant.