高位钻孔瓦斯抽采实践及效果考察

Gas Drainage Practice and Effect Investment by High-level Drillhole

以乌兰煤矿高位钻孔抽采瓦斯为例,对高位钻孔瓦斯抽采的效果进行了分析,结果表明:高位钻孔的终孔位置必须超过最大垮落带高度,布置在距煤层法向距离15 m处,以取得较好的抽采效果;在工作面推过高位钻孔终孔点30 m后,瓦斯抽采浓度开始逐渐增加,并达到基本稳定的状态;在工作面初次来压之前,高位钻孔抽采瓦斯量不大,随着工作面的推进,抽采量逐步上升,抽采效果明显。

Taking high-level drillhole gas drainage in Wulan Coal Mine as example,the drainage effect of high-level drillhole was analysed.The results indicate that: high-level drillhole of end drilling location must over maximum height of caving zone,and should be arranged in the place where normal distance is 15 m far from coal seam to reach better mining effect.When the working face has pushed over high-level drillhole end hole points 30 m,gas drainage concentration began to increase gradually,and reached basic stable state.Before the first weighting,gas drainage concentration of high-level drillhole was not large.With the advancement of working face,the drainage volume increased gradually,and the drainage effect was obvious.