煤层钻孔预抽半径测算模型及其应用效果分析

Calculation Model of Gas Pre-drainage Radius by Boreholes and Analysis on Its Application Effect

基于基本假设,建立煤层钻孔预抽半径计算模型,并分析探讨了模型的解析解问题。在已知安顺煤矿M9煤层原始瓦斯基本参数的基础上,利用推导的公式,测算了M9煤层的预抽期与预抽半径的关系。测定了M9煤层原始煤体和9102及9100回采工作面不同预抽钻孔间距的K1值,对比分析了预抽钻孔间距的合理性。结合测算与现场考察的数据,综合确定了M9煤层预抽时间与预抽半径的关系。

Based on the basic assumptions,a calculation model of gas pre-drainage radius by boreholes in the coal seam was established,and the analytical solution of the model was analyzed and discussed. On the basis of the basic parameters of the original gas in M9 coal seam of Anshun Coal Mine,the relation between the gas pre-drainage time and the pre-drainage radius of M9 coal seam was calculated by using the derived formula. The K1 values of pre-drainage boreholes with different spacings in the original coal bady,9102 and 9100 working faces of M9 coal seam were determined,and the rationality of the pre-drainage borehole spacing was comparatively analyzed. According to the the calculation and on-the-spot inspection data,the relation between the pre-drainage time and pre-drainage radius of M9 coal seam was comprehensively determined.