穿层瓦斯抽采钻孔通管直连新型封孔工艺研究

    Study on New Sealing Technology for Single Tube Connection in Through Layers Gas Drainage Hole

    • 摘要: 为了解决义煤集团孟津煤矿底抽巷穿层钻孔抽采浓度低、衰减快的技术难题,基于矿压“三带”理论,分析钻孔围岩裂隙带分布,明确钻孔抽放时可能漏气的通道,通过工程试验,确定封孔段的长度和位置;根据现场测量的钻孔抽放管不同部位的抽放浓度和地面试验,分析抽放管的漏气环节,确定了抽放钻孔通管直连的连管方式;封孔注浆方面,在分析钻孔封孔工艺流程的基础上,从水灰配比分析浆液终凝的膨胀率,从注浆工艺改进封孔器,经地面和现场试验,得出合理水灰比1∶2和两堵两注封孔器。综合封孔工艺全过程,提出通管直连带压封孔技术。结果表明:采用通管直连带压封孔技术提高钻孔抽采浓度到原来的2倍以上。

       

      Abstract: To solve the technical problem of low concentration and rapid attenuation of drilling in floor gas drainage gateway of Mengjin Coal Mine, we analyze the distribution of the fracture zone in the surrounding rock of the borehole, make clear the channel that may leak when the borehole is drained, and determine the length and position of the sealing section through the engineering test; according to the in-situ measurement of the extraction concentration of different parts of the borehole drainage pipe and the ground test, the leakage link of the drainage pipe was analyzed, and the connecting mode of the drainage pipe through the borehole was determined; in terms of sealing hole grouting, based on the analysis of drilling hole sealing technological process, the expansion rate of the final set of slurry was analyzed from water-cement ratio of 1∶2, and the improved sealing hole was obtained through the ground and field tests. The whole process of hole sealing technology is integrated. The results show that the concentration of borehole extraction can be increased to more than 2 times of the original by using the technology of straight through pipe and joint sealing.

       

    /

    返回文章
    返回