CO2-DISSOLVED: a Novel Concept Coupling Geological Storage of Dissolved CO2 and Geothermal Heat Recovery – Part 4: Preliminary Thermo-Hydrodynamic Simulations to Assess the CO2 Storage Efficiency

Abstract

The CO2-DISSOLVED project aims at assessing the technical-economic feasibility of coupling CO2 storage in a saline aquifer and geothermal heat recovery. The proposed infrastructure basically relies on a standard geothermal doublet where CO2 would be injected after having been entirely dissolved in the cooled brine. The objective of this preliminary thermo-hydrodynamic modeling study was to quantify the expected CO2 storage lifetime and efficiency. The results first confirmed that CO2 will inevitably be produced in the extracted brine after 2-15 years of continuous injection, depending on the operating parameters. However, mass balance calculations evidenced that after a 30 year injection period, 37-85% of the total CO2 injected should remain stored in the aquifer.