IMPACT OF CO2 CONCENTRATION ON TRAPPING MECHANISMS IN SALINE AQUIFERS FOR CCS

The intensification of climate change accelerates the need for development of technologies to reduce CO₂ and CH₄ emissions. Carbon capture and storage (CCS) enable the safe retention of CO₂ in saline aquifers, which offer high storage capacity. The present study uses a siliciclastic saline aquifer model in GEM software to simulate the injection of 30% to 100% CO2 concentrations for 30 years, assessing the impact on physical and chemical trapping mechanisms for a thousand years. Results indicated that in all scenarios, dissolution was the most significant trapping mechanism, consistently followed by structural trapping, with little influence on mineralization. The mineral activity generated the dissolution of clay minerals and feldspars, with precipitation of calcite, dolomite, kaolinite and chalcedony by mineralization. The results suggest that optimizing CO2 concentration can improve the efficiency of CCS projects in saline aquifers.