复采条件下远距离截引老空水技术

Technology of Long-Distance Draining Goaf Water Under the Condition of Repeated Mining

基于韩咀煤矿主运巷老空水疏放实例,深入分析主运巷迎头老空水的形成,选取涌水量最大的常规钻孔B5钻孔为靶点,提出利用远距离下斜-上仰型定向长钻孔疏放老空水。研究结果表明:下斜-上仰型定向长钻孔适用于远距离疏放老空水,钻孔轨迹设计为套管段、直孔段、造斜段、稳斜段、造斜段、稳斜段6部分可实现大角度斜穿老空区,且避免形成疏放水凹槽;采取定向钻进清水介质成孔工艺可确保套管段保直性,煤层底板以下2~7 m砂泥岩互层层位可实现稳定定向钻进;采用回转钻具组合,以低钻压、小扭矩参数可实现老空区平稳钻进,最终成功中靶老空区,实现在老空区钻进了17 m的佳绩,提钻后涌水量达134 m^3/h,共疏放老空水3.6万m^3。

Based on the example of goaf water drainage in the main transportation roadway of Hanzui Coal Mine, the formation of goaf water in the main transportation roadway is deeply analyzed. The conventional borehole B5 with the largest water inflow is selected as the target. It is suggested that the goaf water should be drained by a long directional borehole with long downward slope and upward elevation. The results show that the downward inclined and upward directional long borehole is suitable for long distance drainage of goaf water, and the drilling trajectory is designed as casing section, straight hole section, inclined section,stable inclined section, inclined section and stable inclined section, which can realize large angle oblique penetration through the old empty area. And avoiding the formation of drainage grooves, adopting directional drilling technology of clear water medium to ensure the straightness of casing section, stable directional drilling can be realized in 2 m to 7 m sand and mudstone interbedding below coal floor, and rotary drilling tool assembly is adopted. With the parameters of low drilling pressure and low torque, the smooth drilling in the old empty area can be realized, and finally the target area can be successfully drilled, and the good achievement of drilling 17 m in the old empty area and water inflow up to 134 m^3/h after drilling can be realized. A total of36 000 m^3 of goaf water was released.