顶板高位定向钻孔瓦斯(CO_(2))治理技术研究与应用

Research and application of gas(CO_(2))control technology in roof high-level directional drilling

海石湾煤矿是罕见的煤与瓦斯(CO_(2))突出矿井,为进一步降低工作面回风流和上隅角瓦斯(CO_(2))浓度,设计在62241工作面回风巷施工顶板高位大直径定向钻孔抽采采空区瓦斯(CO_(2)),以孔代巷,解决回采工作面采空区瓦斯(CO_(2))涌出问题;结合“竖三带”理论,对大直径高位定向钻孔最佳布孔范围进行了分析和确定,通过定向钻进技术使钻孔分布在煤层顶板回采断裂带(“O”型圈)内,保障工作面回采过程中的瓦斯抽采通道。顶板高位大直径定向钻孔在平面上的布置距离回风巷10~70 m(控制工作面倾斜长度1/3);高程布置距离煤层顶板16~28 m,有效降低了工作面回采时上隅角和回风流中的瓦斯(CO_(2))浓度。工程应用表明,大直径顶板高位定向钻孔在瓦斯(CO_(2))治理的效果、成本、施工效率等方面均优于传统高位普通拦截钻孔。

Haishiwan Coal Mine is a rare coal and CO_(2) outburst mine,in order to further reduce the return air flow of the working face and the gas(CO_(2))concentration in the upper corner,it is designed to drill large-diameter directional holes at the roof of 62241 working return air entry to drainage gas from the goaf,replacing the roadway with the borehole to solve the problem of gas(CO_(2))emission from the goaf of the working face.On the basis of the theory of"three vertical zones",the optimal hole distribution range of large-diameter high-level directional drilling is analyzed and determined.Through directional drilling technology,the holes are distributed in the mining fracture zone("O"ring)in coal seam roof to ensure the gas drainage channel during the mining process.The large diameter directional drilling at the top of the roof on the plane is 10~70 m away from the return air roadway(controlling one third of the inclined length of the working face);The elevation arrangement is 16~28 m away from the coal seam roof,which effectively reduces the gas(CO_(2))concentration in the upper corner and the return air flow during the mining of the working face.The engineering application shows that the large-diameter roof high-level directional drilling is superior to the traditional high-level ordinary interception drilling in terms of gas(CO_(2))control effect,cost,construction efficiency,etc.