煤层顶板高位大直径定向钻孔瓦斯抽采技术研究

Research on Gas Extraction Technology of Large Diameter Directional Borehole in Upper Part of Coal Seam Roof

在煤层瓦斯抽采工程中,在钻场这些关键区域,布置了6个高位钻孔,这些钻孔布局合理位置精准,能最大限度地抽取邻近层和采空区中的瓦斯。充分考虑瓦斯运移规律,将钻孔层位选定在砂质泥岩与细砂岩的交界面,距离煤层顶板约30~65 m,以确保钻孔能够最大限度地抽取瓦斯。通过这一高位大直径定向钻孔技术,成功实现了对煤层顶板瓦斯的长期、稳定抽采,使采空区瓦斯涌出量得到了有效控制。在测试结果中,钻场内1#~6#孔平均抽采混量为9.76 m3/min,单孔的最大抽采混量为33.992 m3/min,得出高位大直径定向钻孔在瓦斯抽采过程中具有显著效果,对于提升煤矿瓦斯治理水平具有重要意义。随着煤化工行业的快速发展,提升其技术水平具有重要作用,因此需加强这方面研究,才可以更好地实际应用。

In the coal seam gas extraction project,six high level boreholes are arranged in these key areas of the drilling site.The layout of these boreholes is reasonable and accurate,and the gas in the adjacent layer and the gob can be extracted to the maximum extent.Considering the law of gas migration,the drilling layer is selected at the interface of sandy mudstone and fine sandstone,which is about 30~65 m away from the coal seam roof to ensure that the drilling can extract gas to the maximum extent.Through this high and large diameter directional drilling technology,the long-term and stable extraction of coal seam roof gas has been successfully realized,and the gas emission in goaf has been effectively controlled.According to the test results,the average extraction mixing amount of 1#~6#holes in the drilling field is 9.76 m3/min,and the maximum extraction mixing amount of single hole is 33.992 m3/min.It is concluded that high-position large-diameter directional drilling has a remarkable effect in the process of gas extraction,which is of great significance for improving the level of coal mine gas control.With the rapid development of coal chemical industry,it is important to improve its technical level,so it is necessary to strengthen the research in this area to better practical application.