大直径钻孔“以孔代巷”上隅角瓦斯治理参数优化及应用

为解决回采工作面上隅角瓦斯超限问题,提出大直径钻孔"以孔代巷"上隅角瓦斯抽采技术,应用数值模拟方法,对大直径钻孔参数进行了优化,确定了最优孔径、孔距和终孔位置。大直径钻孔"以孔代巷"上隅角瓦斯抽采技术在西曲矿18401工作面现场应用效果表明:大直径钻孔间距为5 m、孔径为350mm及钻孔终孔位置至顶板距离为0.3m时,上隅角瓦斯浓度降至最低,抽采效果最佳;与施工高抽巷抽采进行瓦斯抽采相比,大直径钻孔"以孔代巷"上隅角瓦斯抽采技术施工难度低速度快,成本降低85.79%;工作面回采过程中,上隅角瓦斯浓度均保持在0.2%以下,有效解决了采煤工作面上隅角瓦斯易于集聚的难题,保障了工作面的安全生产。

Optimization and application of gas control parameters in the upper corner of large diameter borehole

In order to solve the problem of gas overrun in the upper corner of the working face, the technology of gas drainage in the upper corner of the working face is put forward. The parameters of the large-diameter drilling are optimized by using the numerical simulation method, and the optimal hole diameter, hole distance and final hole position are determined. The application effect of large-diameter drilling in the 18401 working face of Xiqu mine shows that: when the spacing between large-diameter drilling holes is 5M and the aperture is 350mm, the gas drainage effect of the upper corner is the best; compared with the high extraction, the cost of gas drainage in the upper corner of the large-diameter drilling hole is reduced by 85.79%; in the process of mining, the gas concentration of the upper corner is reduced by 85.79% All of them are kept below 0.2%, which effectively controls the gas concentration in the upper corner and ensures the safety production of the working face.