Techniques for Increasing CO2 Dissolution in the Aquifer with Temperature Variation

Abstract

Carbon Capture and Storage (CCS) is a possible option to mitigate the rise in anthropogenic CO2. When CO2 is injected into a storage formation, it migrates upwards under buoyancy until it reaches the caprock. Of the CO2 that does not dissolve, some may be trapped under the caprock as a free phase and the rest will migrate laterally, which could subsequently cause a risk of CO2 leakage out of a storage complex. First, in this study, pure CO2 injection is examined on a synthetic model and then sensitivity analyses were conducted for some of the fluid, rock and injection parameters. The results of this study show that the extent to which CO2 has been convected in the porous media in the reservoir plays a vital role in improving the CO2 dissolution in brine and safety of its long-term storage. Different injection methods have been already proposed by different researchers to improve the solubility of CO2 in the formation brine. In this study a novel injection technique is presented, its aim being to cool down (liquefy) the supercritical CO2 injected in the wellbore using a downhole cooler equipment. The higher temperature CO2 enters the cooling equipment and exits with a lower temperature further downstream. The colder (liquid) CO2 has a higher solubility in brine, higher density and viscosity, which increases the security of the CO2 storage. Then the impacts of wettability conditions on the solubility of CO2 in the aquifer are not well covered in the literature. Therefore, in order to address this dearth of information, in the work presented here we studied the influence of wettability conditions on the CO2 solubility in a synthetic and hypothetical saline aquifer storage models using numerical methods (i.e. ECLIPSE software). Additionally, the influence of temperature on modifying the relative permeability curves based on the relative permeability models and on the CO2 solubility in an aquifer is investigated using numerical methods. Finally, the temperature differences and non-isothermal effects can be used to monitor CO2 movement in the reservoir. In this study first, the non-isothermal temperature profile in the tubing is calculated then the temperature distribution in the reservoir is investigated to trace the CO2 plume migration in the formation of the Containment and Monitoring Institute (CaMI) field research station, Alberta, Canada

Date of Award	Sep 2021
Original language	English
Awarding Institution	Coventry University
Supervisor	Seyed Shariatipour (Supervisor)