title: Analytical solutions to dissolved contaminant plume evolution with source depletion during carbon dioxide storage.
abstract: Volatile contaminants may migrate with carbon dioxide (CO2) injection or leakage in subsurface formations, which leads to the risk of the CO2 storage and the ecological environment. This study aims to develop an analytical model that could predict the contaminant migration process induced by CO2 storage. The analytical model with two moving boundaries is obtained through the simplification of the fully coupled model for the CO2-aqueous phase -stagnant phase displacement system. The analytical solutions are confirmed and assessed through the comparison with the numerical simulations of the fully coupled model. Then, some key variables in the analytical solutions, including the critical time, the locations of the dual moving boundaries and the advance velocity, are discussed to present the characteristics of contaminant migration in the multi-phase displacement system. The results show that these key variables are determined by four dimensionless numbers, Pe, RD, Sh and RF, which represent the effects of the convection, the dispersion, the interphase mass transfer and the retention factor of contaminant, respectively. The proposed analytical solutions could be used for tracking the migration of the injected CO2 and the contaminants in subsurface formations, and also provide an analytical tool for other solute transport in multi-phase displacement system.
authors.affiliation: Department of Chemical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Chemical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China; Key Laboratory of Thermo-Fluid Science and Engineering, Ministry of Education, Xi'an, Shaanxi 710049, PR China. Electronic address: yzliu@mail.xjtu.edu.cn.
authors.forename: Yongzhong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Chemical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yu
authors.affiliation: Department of Chemical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China.
authors.forename: Tian
authors.initials: T
authors.lastname: Ding
mesh_terms: D002245:Carbon Dioxide; D057965:Carbon Sequestration; D008962:Models, Theoretical; D012996:Solutions; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D012996:Solutions; D014874:Water Pollutants, Chemical; D002245:Carbon Dioxide
keywords: Analytical solution; CO(2) storage; Contaminant migration; Multi-phase displacement; Source depletion