低透气煤层中定向长钻孔瓦斯抽采技术应用研究

Study on the Application of Directional Long Borehole Gas Drainage Technology in Low Permeability Coal Seams

针对低透气煤层采用顺层钻孔抽采煤层瓦斯存在的抽采效率低、钻孔工程量大、工程周期长等不足,以晋能控股煤业集团某矿1208工作面瓦斯抽采工况为例,提出了应用定向长钻孔技术进行工作面瓦斯抽采的策略,具体介绍了定向长钻孔施工技术的优点,主要用到的设备及钻孔的布置。应用结果表明:与煤层顺层钻孔瓦斯抽采技术相比,采用定向长钻孔施工技术抽采瓦斯,可缩短钻孔长度4500 m,可使钻孔成孔率提升1.5倍,瓦斯抽采效率提高1.7倍,瓦斯抽采效果显著。

In view of the shortcomings of low gas drainage efficiency,large amount of drilling work and long engineering period in low permeability coal seam gas drainage by bedding drilling,taking the gas drainage working condition of 1208 working face of a mine of Jinneng Holding Coal Industry Group as an example,the strategy of gas drainage in working face by using directional long drilling technology is proposed,and the advantages of directional long drilling construction technology,the main equipment used and the layout of drilling holes are specifically introduced.The application results show that compared with the gas drainage technology of coal seam bedding boreholes,the gas drainage technology of directional long boreholes can shorten the length of boreholes by 4500 m,increase the hole forming rate of boreholes by 1.5 times,increase the gas drainage efficiency by 1.7 times,and achieve remarkable gas drainage effect.