三软低透气性大采长工作面抽采空白带分析与治理

摘要

针对新丰煤矿25021工作面为三软低透气性、大采长、煤与瓦斯突出危险工作面的特点，开采11051工作面作为保护层，消除该工作面突出危险性，采用底抽巷穿层钻孔结合上、下副巷顺层钻孔的立体抽采系统抽采25021工作面的卸压瓦斯。但在实际施工过程中，顺层钻孔在松软煤层中钻进存在困难，穿层钻孔由于出现钻孔弯曲现象，均没有打到设计区域，未能对25021工作面中部的卸压瓦斯进行有效抽采，论证分析了25021工作面中部存在抽采空白带，在25021工作面切巷内向工作面前方100 m施工瓦斯抽采钻孔，抽采工作面中部的瓦斯，对抽采空白带进行有效治理，消除了工作面的突出危险性。%In view of the characteristics of No. 25021 dangerous working face of Xinfeng Coal Mine,including “three soft”,great mining length,coal and gas burst,No. 11051 working face was mined as protective seam to eliminate the risk at No. 25021 working face. The gas at No. 25021 working face was released by drilling through stratum from bed plate tunnel combined with drilling from upper and lower auxiliary tunnels. But during the actual construction,it was diffi-cult to drill in the soft seam along the seam,while the boreholes bent during drilling through stratum. Therefore,the boreholes did not reach designed zones via above methods. The analysis demonstrated that there existed gas drainage blank zone in the middle of No. 25021 working face. The boreholes were drilled at the position of 100 m ahead of this working face from cross tunnel to drain the gas in the middle of working face. The gas drainage blank zone was controlled effec-tively,and the risk of outburst at the working face was eliminated.