定向钻进技术在断层发育矿井瓦斯抽采中的应用

Application of Directional Drilling Technology in Gas Extraction of Developmental Faluts Mine

定向钻进技术以其轨迹可控、成孔较深的优势,逐步被应用于复杂地质条件的煤矿井下瓦斯抽采。针对化乐矿断层松软破碎、层序紊乱、成孔性差的问题,介绍了定向钻进技术原理与装备,从钻孔角度分析了煤矿瓦斯抽采制约因素,总结出注浆加固与定向钻进结合的成孔方法,形成了滑动定向钻进工艺避开断层破碎带的实践经验。现场施工8组钻孔,其中孔深300 m以上定向长钻孔4组,累计抽采瓦斯375840 m^(3),抽采率达到77%,单孔抽采初始浓度70%~85%,流量0.1~0.5 m^(3)/min,有效解决了掘进工作面瓦斯超限问题。

Directional drilling technology,with its advantages of controlled trajectory and deeper hole formation,has been gradually applied to underground gas extraction in coal mines with complex geological conditions.Aiming at the problems of loose and broken faults,disorderly layer sequence and poor hole formation in Huale mine,introduced the principle and equipment of directional drilling technology,analyzed the constraints of coal mine gas extraction from the perspective of drilling,summarized the combination of grouting reinforcement and directional drilling method,and formed the practical experience of sliding directional drilling process to avoid the fracture zone of faults.There are 8 groups of drilling hole had been constructed on site,including 4 groups of hole deeper than 300 m,the total extraction of gas is 375840 m^(3),extraction rate reached 77%,single hole extraction initial concentration remains 70%-85%,flow rate is between 0.1-0.5 m^(3)/min,that effectively solve the problem of gas overload in the dredging workface.