Impact of chemical reactions on convective and diffusive transport of dissolved CO2 in saline aquifers
Author Identifier (ORCID)
Zhenjiang You: https://orcid.org/0000-0002-4843-2107
Abstract
Chemical reactions frequently occur during CO2 dissolution trapping regarded as one of the promising mechanisms for CO2 storage in saline aquifers. In this work, a convective-reactive transport model for CO2 dissolution in saline aquifers is developed, taking into account the effects of produced ions on brine density and the alterations of porosity and permeability. Four different model conditions are numerically compared to analyze the effects of chemical reactions on CO2 dissolution. Subsequently, the effects of three factors, including initial content, reaction rate and distribution characteristics of CaCO3 on CO2 plume migration are discussed. Simulation results indicate that CO2 plume migration in saline aquifers is delayed, if the effects of produced ions and porosity alterations induced by chemical reactions are ignored. Otherwise, chemical reactions can accelerate the density-driven instability if the effect of produced ions on brine density is considered. The effect of CaCO3 dissolution on the time for CO2-brine complete mixing depends on the CO2 consumption rate and the increased CO2 flux. An increase in CaCO3 content, reaction rate and distribution heterogeneity can accelerate the density-driven instability, and strengthen the total flux of dissolved CO2. This also facilitates the rapid formation of preferential pathways for CO2 migration. The findings of this work enhance our understanding of CO2 dissolution trapping mechanisms, particularly in the context of chemical reactions in saline aquifers.
Document Type
Journal Article
Date of Publication
9-1-2025
Volume
522
Publication Title
Journal of Cleaner Production
Publisher
Elsevier
School
Centre for Sustainable Energy and Resources / School of Engineering
Funders
National Natural Science Foundation of China (42407065 ) / Natural Science Foundation of Jiangsu Province (BK20230647 ) / Natural Science Research Project of Higher-Education Institutions of Jiangsu Province (23KJD610001 ) / National Overseas Top Talents Program of China (JXRSB02001)
Copyright
subscription content
Comments
Tan, Q., Zhuang, Y., Peng, H., Tian, R., Li, Z., & You, Z. (2025). Impact of chemical reactions on convective and diffusive transport of dissolved CO2 in saline aquifers. Journal of Cleaner Production, 522, 146347. https://doi.org/10.1016/j.jclepro.2025.146347