{"title":"Modeling and Analysis on Coal Permeability Considering the Mineral Dissolution Caused by Flue Gas in Fractures","authors":"Yu Shi, Baiquan Lin, Ting Liu* and Yang Zhao, ","doi":"10.1021/acs.energyfuels.4c0421810.1021/acs.energyfuels.4c04218","DOIUrl":null,"url":null,"abstract":"<p >Permeability enhancement by injecting acidified flue gas to dissolve minerals within coal fractures offers a novel approach to solve the problem of gas drainage from deep, strongly adsorbent, and low-permeability coal seams. However, the dynamic response mechanisms of the internal expansion coefficient, fracture bulk modulus, and permeability during mineral dissolution in coal fractures remain unclear. To address this problem, we constructed a permeability model that considers the dynamic changes of the internal expansion coefficient and fracture bulk modulus during mineral dissolution based on the “matrix-rock bridge-fracture” physical model of coal. Then, the permeability changes of mineral-containing coal under a constant gas pressure, a constant effective stress, and a constant confining pressure at different reaction times were tested and analyzed using the self-built CO<sub>2</sub>–H<sub>2</sub>O–Coal interaction and permeability test system. Based on the fitting results between the constructed permeability model and the experimental data, we delved into the dynamic evolution patterns of the internal expansion coefficient and the fracture bulk modulus during mineral dissolution in coal fractures. Ultimately, the separate and coupling influences of key parameters of the model (soluble mineral content variation, initial fracture porosity, Langmuir strain constant, Langmuir pressure constant, and average molar volume of soluble minerals) on the coal permeability were clarified by utilizing local and global sensitivity analysis of the verified permeability model. This study can provide a theoretical reference for engineering permeability enhancement by mineral dissolution using flue gas.</p>","PeriodicalId":35,"journal":{"name":"Energy & Fuels","volume":"38 23","pages":"22848–22863 22848–22863"},"PeriodicalIF":5.2000,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Energy & Fuels","FirstCategoryId":"5","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acs.energyfuels.4c04218","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
Permeability enhancement by injecting acidified flue gas to dissolve minerals within coal fractures offers a novel approach to solve the problem of gas drainage from deep, strongly adsorbent, and low-permeability coal seams. However, the dynamic response mechanisms of the internal expansion coefficient, fracture bulk modulus, and permeability during mineral dissolution in coal fractures remain unclear. To address this problem, we constructed a permeability model that considers the dynamic changes of the internal expansion coefficient and fracture bulk modulus during mineral dissolution based on the “matrix-rock bridge-fracture” physical model of coal. Then, the permeability changes of mineral-containing coal under a constant gas pressure, a constant effective stress, and a constant confining pressure at different reaction times were tested and analyzed using the self-built CO2–H2O–Coal interaction and permeability test system. Based on the fitting results between the constructed permeability model and the experimental data, we delved into the dynamic evolution patterns of the internal expansion coefficient and the fracture bulk modulus during mineral dissolution in coal fractures. Ultimately, the separate and coupling influences of key parameters of the model (soluble mineral content variation, initial fracture porosity, Langmuir strain constant, Langmuir pressure constant, and average molar volume of soluble minerals) on the coal permeability were clarified by utilizing local and global sensitivity analysis of the verified permeability model. This study can provide a theoretical reference for engineering permeability enhancement by mineral dissolution using flue gas.
期刊介绍:
Energy & Fuels publishes reports of research in the technical area defined by the intersection of the disciplines of chemistry and chemical engineering and the application domain of non-nuclear energy and fuels. This includes research directed at the formation of, exploration for, and production of fossil fuels and biomass; the properties and structure or molecular composition of both raw fuels and refined products; the chemistry involved in the processing and utilization of fuels; fuel cells and their applications; and the analytical and instrumental techniques used in investigations of the foregoing areas.