穿越采空区氮气钻井工艺应用研究

Application of nitrogen drilling process in goaf of coal mine

摘要:

以寺河矿区穿越采空区氮气钻井试验为背景，通过分析煤层取心测试数据，指出钻井穿越3号煤层采空区抽采9+15号煤层瓦斯的必要性。利用“三带”理论明确了3号煤层采空区顶板以上74.4 m及底板以下22.73 m为钻井漏失带，采用氮气钻井穿越该层段有助于安全高效施工；优化了穿越采空区氮气钻井的三开井身结构；根据穿越采空区氮气钻井工艺需要，配套设计了地面钻井工艺流程。氮气钻井工艺在寺河矿区试验的成功，证明该工艺的可行性，对穿越采空区钻井技术的研究和推广应用具有重要的指导意义。

Abstract:

Based on nitrogen drilling testing in the goaf of Sihe coal mine, the necessity of drilling through the goaf in 3# coal seam to extract gas from 9+15# coal seam was proposed by analyzing the testing data of cores recovered from the coal seam. Based on “three band” theory, it was confirmed that there are drilling leakage zones present in 3# coal seam, which are located at 74.4m above the roof and 22.73m below the floor of the goaf respectively. Using nitrogen fluid to drill these zones can ensure drilling safety and improve the drilling efficiency. In order to meet the requirement of nitrogen drilling, the well structure with three sections and the surface drilling process were optimized. The successful application of the nitrogen drilling process in Sihe mine indicates that this process can be used in the goaf of coal mine, which provides an important guide for the research and application of drilling technology in goaf.