南阳煤业3号煤层抽采钻孔布孔方案优化研究

Study on Spatiotemporal Evolution Characteristics of Three Zones of Spontaneous Combustion in Goaf and its Prevention and Control Technology

针对3号煤层钻孔抽采试验效果不佳及钻孔合理间距布设困难等问题,借助COMSOL数值解算软件,从钻孔有效抽采半径影响因素及群孔抽采合理布设的角度分析了不同情况下瓦斯抽采效果差异,优化了3203工作面群孔布设参数。结果表明:抽采钻孔影响半径与抽采钻孔直径、抽采钻孔负压、抽采钻孔时间密切相关;群孔抽采时受钻孔叠加效应影响区,存在最佳布设钻孔间距,预抽时间按100 d计算,群孔布设间距合理范围为3~4 m。结合煤层实际赋存条件提出了交错式布孔方案,现场应用效果良好,布孔优化合理。

In view of the poor effect of drilling and pumping test in 3\3 coal seam and the difficulty of reasonable spacing layout of boreholes,with the help of COMSOL numerical solution software, the difference of pumping effect under different conditions is analyzed from the perspective of the factors affecting the effective pumping radius of boreholes and the reasonable layout of group hole pumping, and the group hole layout parameters of 3203 working face are optimized. The results show that the influence radius of the pumping hole is closely related to the diameter of the pumping hole, the negative pressure of the pumping hole and the time of the pumping hole;In the area affected by borehole superposition effect during group hole pumping, there is an optimal arrangement of borehole spacing. The pre pumping time is calculated as100D, and the reasonable arrangement spacing of group holes is 3-4m. Combined with the actual occurrence conditions of coal seams, the staggered hole layout scheme is put forward. The field application effect is good, and the optimization of hole layout is reasonable, which provides a certain reference for the layout of boreholes in similar coal seams.