文献类型：期刊文献

英文题名：Numerical analysis of migration and sequestration dynamics of dense liquid CO2 in offshore shallow saline aquifers

作者：Wang, Yanyong[1,2];Li, Song[1,2];Jayaprakash, Vishnu[3];Peng, Xiyi[1,2];Shi, Jialin[4];Jiang, Jiatong[5,6]

机构：[1]Chengdu Univ Technol, Coll Energy, Chengdu 610059, Peoples R China;[2]Chengdu Univ Technol, State Key Lab Oil & Gas Reservoir Geol & Exploitat, Chengdu 610059, Peoples R China;[3]Univ Alberta, Dept Civil & Environm Engn, Edmonton, AB T6G 1H9, Canada;[4]East China Univ Sci & Technol, Sch Chem & Mol Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[5]China Univ Petr Beijing Karamay, Sch Petr, Beijing, Peoples R China;[6]China Univ Petr, State Key Lab Petr Resources & Engn, Beijing, Peoples R China

年份：2025

卷号：205

外文期刊名：ADVANCES IN WATER RESOURCES

收录：;EI(收录号：20253118908197);WOS:【SCI-EXPANDED(收录号:WOS:001543237700002)】；

基金：The authors would like to acknowledge the financial support by the Sichuan Science and Technology Program (Grant No. 2022YFSY0008) , Chengdu University of Technology 2023 Young and Middle-aged Backbone Teachers Development Funding Program (Grant No. 10912-JXGG2023-08522) , and Science Foundation of China University of Petroleum, Beijing.

语种：英文

外文关键词：Geological CO2 storage; Offshore shallow saline aquifers; Liquid CO2; Capillary force; Heterogeneity

摘要：Geological sequestration of CO2 in saline aquifers presents a promising strategy for large-scale greenhouse gas mitigation. While most existing studies have focused on the storage of supercritical CO2, in the high-pressure and low-temperature conditions typical of offshore shallow saline aquifers, CO2 may exist in a dense liquid phase. This phase exhibits distinct properties such as higher density and viscosity, which significantly influence its migration behavior and trapping forms. In this study, we develop numerical models to simulate CO2 injection into offshore shallow saline aquifers, incorporating key trapping processes, including local capillary trapping, residual trapping, and dissolution trapping. High-resolution two-phase flow simulations are employed to investigate the spatiotemporal evolution of CO2 plume and the dynamic transition of sequestration forms. We systematically evaluate the impacts of the CO2 phase state, formation heterogeneity (characterized by dimensionless horizontal/vertical autocorrelation lengths and heterogeneity degree), and injection rate on CO2 migration and storage performance. The results highlight distinct differences in migration patterns and trapping mechanisms between liquid-phase and supercritical CO2 in offshore saline aquifers. Formation heterogeneity, particularly the autocorrelation length and global heterogeneity of the permeability field, plays a critical role in controlling plume evolution and sequestration efficiency. Saline aquifers with larger horizontal autocorrelation lengths or higher heterogeneity exhibit underutilized storage capacity despite reduced leakage risk through the caprock. In contrast, saline aquifers with larger vertical autocorrelation lengths tend to achieve higher storage efficiency but are associated with increased leakage potential. Under high injection rates, CO2 is more likely to invade pores with higher capillary entry pressures, resulting in elevated saturations near the injection zone. These findings offer valuable insights into the migration dynamics and long-term stability of liquid-phase CO2 in offshore shallow saline aquifers and guide the safe and efficient implementation of CO2 sequestration strategies in such settings.