沁水盆地过采空区煤层气水平井施工技术研究

Research on drilling technology for coalbed methane horizontal wells through mining goafs in Qinshui Basin

摘要:

为了进一步解决山西晋城矿区煤层气的开发利用问题，科学有效地开发和利用3号煤层采空区下部的煤层气，降低煤层中的瓦斯含量，以保障煤层气的高效合理利用，为煤矿开采提供安全保障。本文对该区穿采空区煤层气水平井的施工工艺进行了研究，提出了利用潜孔锤及空气螺杆+氮气施工的钻井工艺，进一步优化了钻井的井身结构，有效地解决了采空区敏感层段的坍塌、掉块、漏失等施工难题。穿采空区煤层气水平井的顺利施工，进一步验证了该钻井技术的可行性，对下一步煤层气的规模性开发具有重要的指导意义。

Abstract:

In order to further solve the development and utilization of coal bed methane in the Shanxi Jincheng mining area， coalbed methane in the lower goaf of the 3^# coal seam should be properly and effectively exploited and utilized to reduce the content of gas in the coal seam so as to ensure the efficient and rational use of coalbed methane， and provide safety guarantee for coal mining. This paper studies drilling technology for CBM horizontal wells through goafs in this area with the drilling process with DTH hammer and air PDM plus nitrogen put forward. With optimization of the well structure， the construction problems such as collapse， falling blocks and leakage in sensitive stratum in goafs were effectively solved. The smooth completion of coal-bed methane horizontal wells through goafs has verified the feasibility of the drilling technology， can provide guide for the coming large-scale development of coalbed methane.