本煤层瓦斯抽采钻孔注浆堵漏风技术

Grouting and plugging technology of in-seam borehole methane drainage

在对本煤层钻孔围岩漏气机理及堵漏风原理进行分析的基础上,提出了一种分空间、错时间以切断漏气通道的注浆堵漏技术;分空间体现在将钻孔的密封段分为空腔段及预留段进行注浆堵漏,错时间体现在将该技术工艺流程分为3个阶段:准备、一次注浆及二次堵漏阶段。另外,设计了一体化专用封孔器及注浆作业配套设备;为验证新注浆堵漏技术的应用效果,在山西某高瓦斯矿开展了钻孔注浆堵漏风技术试验研究。研究结果表明:应用新注浆堵漏技术之后,钻孔瓦斯抽采浓度立即大幅回升,本煤层钻孔抽采寿命由40 d左右增至80 d以上,钻孔有效抽采时间延长到原来的2.1倍以上。

Based on the analysis of the gas leakage mechanism and the principle of plugging in the surrounding rock of the in-seam borehole, a new grouting and plugging technology by separating the space and staggering time to cut off the air leakage channel was proposed. The separating space was embodied in dividing the sealing section of the borehole into a cavity section and a reserved section and a reserved section for grouting and plugging. The staggering time reflected in dividing the technical process into three stages: preparation, primary grouting and secondary plugging stages. In addition, an integrated special borehole sealing device and supporting equipment for grouting operations were designed. In order to verify the effect of the new grouting and plugging technology, a test study on the borehole grouting and plugging technology was carried out in a high gas mine in Shanxi Province. The research results showed that the concentration of gas drainage in boreholes immediately rebounded sharply, the life of in-seam borehole had increased from about 40 days to more than 80 days, and the effective drainage time of borehole had been extended to more than 2.1 times the original drainage time after the application of the new grouting and plugging technology.