文献类型：期刊文献

英文题名：Determination of Key Technical Parameters in the Study of New Pressure Sealing Technology for Coal Seam Gas Extraction

作者：Sun, Zhongguang Li, Xuelong Wang, Kequan Wang, Fakai Chen, Deyou Li, Zhen

第一作者：Sun, Zhongguang

通信作者：Li, XL[1]

机构：[1]State Key Lab Gas Disaster Detecting Preventing &, Chongqing 400037, Peoples R China;[2]Shandong Univ Sci & Technol, Coll Energy & Min Engn, Qingdao 266590, Peoples R China;[3]China Coal Technol & Engn Grp Chongqing Res Inst, Chongqing 400039, Peoples R China;[4]Chongqing Univ, Coll Resources & Environm Sci, State Key Lab Coal Mine Disaster Dynam & Control, Chongqing 400044, Peoples R China;[5]Guizhou Inst Technol, Coll Min Engn, Guiyang 550000, Peoples R China

第一机构：State Key Lab Gas Disaster Detecting Preventing &, Chongqing 400037, Peoples R China

通信机构：corresponding author), Shandong Univ Sci & Technol, Coll Energy & Min Engn, Qingdao 266590, Peoples R China.

年份：2022

卷号：19

期号：9

外文期刊名：INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH

收录：;Scopus(收录号：2-s2.0-85128425339);WOS:【SSCI(收录号:WOS:000794372200001)，SCI-EXPANDED(收录号:WOS:000794372200001)】；

基金：This work is financially supported by the Science Innovation and Entrepreneurship Special Funded Projects of China Coal Technology & Engineering Group (2020-TD-ZD007), the Natural Science Foundation of Chongqing China (cstc2020jcyj-msxmX0972, cstc2019jcyj-bsh0041 & cstc2019jcyjmsxmX0633), the National Natural Science Foundation of China (52104204), the Natural Science Foundation of Shandong Province (ZR2021QE170), the Natural Science Foundation of Shandong Province (ZR202103050647), which are gratefully acknowledged. The authors also thank the editor and anonymous reviewers very much for their valuable advice.

语种：英文

外文关键词：coal seam; gas drainage; disturbance crack; pressure sealing; polyurethane; cement slurry

摘要：Coal is affected by the concentrated stress disturbance of mining, the disturbance of drilling hole formation, and the concentrated stress of coal shrinkage and splitting of gas desorption from the hole wall; these result in a large number of secondary cracks that collect and leak gas. As a result, it is difficult for the coal seam sealing process to meet engineering quality sealing requirements, which results in problems such as low gas concentration during the extraction process. In this paper, based on the analysis of coal pore and fissure characteristics, and in view of the current situation of gas drainage and sealing in this coal seam, combined with the existing grouting and sealing technology, it is proposed to use pressure grouting and sealing to realize the sealing of deep coal bodies in the hole wall. According to the field conditions, the experimental pressure sealing parameter index is as follows: theoretical sealing length L-1 = 9.69 m, the sealing length L-2 = 13.98 m is verified, and the final sealing length is determined to be 15 m; the sealing radius is determined to be 0.6 m; the cement slurry was prepared on site with a water: cement ratio of 2:1; P-G = 0.43 MPa was calculated; the range of the slurry diffusion radius R was 93.4-176.6 cm; the grouting pressure was determined to be 0.516 MPa. Field application practice has proved that: (1) Under the same drilling parameters and sealing parameters, the gas drainage effect of drilling with pressure sealing is 2.3 times higher than that without pressure sealing; (2) Using traditional sealing technology for drilling holes, the gas extraction concentration is far lower than the sealing operation effect of using the pressure sealing process; (3) Reasonably extending the length of the gas extraction drilling and sealing is a basic guarantee for realizing a substantial increase in the gas extraction concentration; (4) Sealing with pressure leads to a reliable and stable hole process.