成庄矿顺层钻孔布置方案优化研究与应用

Research and application of optimal drilling layout plan of Chengzhuang Mine

成庄矿3号煤层回采工作面面临瓦斯浓度过高的问题,顺层钻孔瓦斯预抽技术的治理效果不明显,为进一步提高工作面瓦斯预抽的效果,以5318工作面的瓦斯预抽为背景,采用流量法测定5318工作面顺层钻孔抽采半径,通过计算分析,对顺层钻孔的布置方式进行优化。结果表明,5318工作面顺层钻孔有效抽采半径为3.3 m<r≤4 m,设计采用双层“三花眼”式布孔方式进行抽采,同排钻孔间距为5.0 m,排距为3.5 m,现场应用过程中,煤层内的残余瓦斯压力与瓦斯含量均复合标注,取得了良好的预抽效果。

The mining face of No.3 coal seam in Chengzhuang Mine facing the problem of excessive gas concentration,the treatment effect of the gas pre-drainage technology in the bedding borehole was not obvious.In order to improve the drainage effect,pre-drainage of 5318 working face was taken as the background.The flow method was used to determine the extraction radius of the bedding borehole in the working face,and the layout of the bedding borehole was optimized through calculation and analysis.The results showed that the effective extraction radius of the layered borehole on the 5318 working face was 3.3 m<r≤4 m.A double-layer"three-flower eye"type hole layout method for extraction was adopted,and the spacing of the boreholes in the same row was 5.0 m and the row spacing was 3.5 m.In the field application process,the residual gas pressure and gas content in the coal seam met all standards,with good pre-draining effect.