Modeling of Spatiotemporal Thermal Response to CO ₂ Injection in Saline Formations: Interpretation for Monitoring

We evaluated the thermal processes with numerical simulation models that include processes of solid NaCl precipitation, buoyancy-driven multiphase SCCO ₂ migration, and potential non-isothermal effects. Simulation results suggest that these processes-solid NaCl precipitation, buoyancy effects, JT cooling, water vaporization, and exothermic SCCO ₂ reactions-are strongly coupled and dynamic. In addition, we performed sensitivity studies to determine how geologic (heat capacity, brine concentration, porosity, the magnitude and anisotropy of permeability, and capillary pressure) and operational (injection rate and injected SCCO ₂ temperature) parameters may affect these induced thermal disturbances. Overall, a fundamental understanding of potential thermal processes investigated through this research will be beneficial in the collection and analysis of temperature signals collectively measured from monitoring wells.