Xiangyun Su , Dongyang Han , Fan Wu , Yueping Qin , Shibin Wang
{"title":"基于计算机断层成像技术的煤层灌浆密封减渗评价","authors":"Xiangyun Su , Dongyang Han , Fan Wu , Yueping Qin , Shibin Wang","doi":"10.1016/j.jgsce.2025.205736","DOIUrl":null,"url":null,"abstract":"<div><div>Sealing pores and fractures in coal seams through grouting is essential for improving gas extraction efficiency. In this work, we conducted a comprehensive approach involving grouting tests, X-ray computed tomography (CT) scanning experiments, and three-dimensional (3D) model reconstruction to investigate the impact of ultrafine cement slurry on the mitigation of drilling air leakage. Pore network models were constructed to analyze the pore size distribution, porosity, connectivity, and fractal dimension. The sealing effect was quantitatively evaluated by the variation of permeability parameters before and after grouting. The results show that: (i) The ultrafine cement with a particle median diameter of 3.22 μm effectively reduces air leakage. Grouting distinctly decreases the sizes of pores and fractures, with the cement slurry playing a key role in sealing fractures. (ii) After grouting, parameters including pore radius, porosity, and connectivity of coal distinctly decreased. The connected porosity in different regions is reduced by 0.57 %, 1.96 %, 1.09 %, and 4.72 %, respectively. (iii) The permeability of the four models decreased by 62.38 %, 62.56 %, 59.93 %, and 71.07 % after grouting, respectively. This research aims to provide a foundation for the grouting sealing engineering test of drilling gas extraction.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"143 ","pages":"Article 205736"},"PeriodicalIF":5.5000,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Evaluation of sealing and permeability reduction during coal seam grouting based on computed tomography imaging technique\",\"authors\":\"Xiangyun Su , Dongyang Han , Fan Wu , Yueping Qin , Shibin Wang\",\"doi\":\"10.1016/j.jgsce.2025.205736\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Sealing pores and fractures in coal seams through grouting is essential for improving gas extraction efficiency. In this work, we conducted a comprehensive approach involving grouting tests, X-ray computed tomography (CT) scanning experiments, and three-dimensional (3D) model reconstruction to investigate the impact of ultrafine cement slurry on the mitigation of drilling air leakage. Pore network models were constructed to analyze the pore size distribution, porosity, connectivity, and fractal dimension. The sealing effect was quantitatively evaluated by the variation of permeability parameters before and after grouting. The results show that: (i) The ultrafine cement with a particle median diameter of 3.22 μm effectively reduces air leakage. Grouting distinctly decreases the sizes of pores and fractures, with the cement slurry playing a key role in sealing fractures. (ii) After grouting, parameters including pore radius, porosity, and connectivity of coal distinctly decreased. The connected porosity in different regions is reduced by 0.57 %, 1.96 %, 1.09 %, and 4.72 %, respectively. (iii) The permeability of the four models decreased by 62.38 %, 62.56 %, 59.93 %, and 71.07 % after grouting, respectively. This research aims to provide a foundation for the grouting sealing engineering test of drilling gas extraction.</div></div>\",\"PeriodicalId\":100568,\"journal\":{\"name\":\"Gas Science and Engineering\",\"volume\":\"143 \",\"pages\":\"Article 205736\"},\"PeriodicalIF\":5.5000,\"publicationDate\":\"2025-07-19\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Gas Science and Engineering\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2949908925002006\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"0\",\"JCRName\":\"ENERGY & FUELS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Gas Science and Engineering","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2949908925002006","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"0","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
Evaluation of sealing and permeability reduction during coal seam grouting based on computed tomography imaging technique
Sealing pores and fractures in coal seams through grouting is essential for improving gas extraction efficiency. In this work, we conducted a comprehensive approach involving grouting tests, X-ray computed tomography (CT) scanning experiments, and three-dimensional (3D) model reconstruction to investigate the impact of ultrafine cement slurry on the mitigation of drilling air leakage. Pore network models were constructed to analyze the pore size distribution, porosity, connectivity, and fractal dimension. The sealing effect was quantitatively evaluated by the variation of permeability parameters before and after grouting. The results show that: (i) The ultrafine cement with a particle median diameter of 3.22 μm effectively reduces air leakage. Grouting distinctly decreases the sizes of pores and fractures, with the cement slurry playing a key role in sealing fractures. (ii) After grouting, parameters including pore radius, porosity, and connectivity of coal distinctly decreased. The connected porosity in different regions is reduced by 0.57 %, 1.96 %, 1.09 %, and 4.72 %, respectively. (iii) The permeability of the four models decreased by 62.38 %, 62.56 %, 59.93 %, and 71.07 % after grouting, respectively. This research aims to provide a foundation for the grouting sealing engineering test of drilling gas extraction.