Carbonated Water Injection for Enhanced Oil Recovery and CO₂ Geosequestration in Different CO₂ Repositories: A Review of Physicochemical Processes and Recent Advances

Abstract

With increasing global energy demand and the urgency to reduce carbon emissions, carbonated water injection has been proposed to tackle these pressing concerns. Carbonated water injection (CWI) in oil formations enhances oil production to support the global energy mix and tackle the issues of energy security, energy equity, and environmental sustainability. However, CWI in oil reservoirs and saline aquifers initiates multiple chemical reactions that promote carbon mineralization, cause formation damage problems, sea-bed subsidence, and reservoir compaction, increase the injection pressure requirement, and consequently affect the practicality of CWI for enhanced oil recovery (EOR) and CO 2 storage. We therefore extensively reviewed the performance of CWI for EOR and CO 2 storage and the implications of these interactions on EOR and CO 2 storage. The analysis covered recent advancements in CWI, including its synergy with various EOR techniques where it was identified that combining CWI with surfactants, polymers, mutual solvents, and nanomaterials significantly improved oil recovery in tight formations (37− 65%) compared to standalone CWI (35−36%), but the CO 2 storage potential of the hybrid technique remains unexplored. Additionally, the complex geochemical interactions that occur during CWI, the influencing variables of these interactions, and their consequence on EOR and CO 2 storage were discussed. The rigorous analysis revealed that the existing literature lacks consensus on the effects of CWI on pore structure. Geochemical interactions caused a −12% to +95% porosity change and a −96% to +417% alteration in permeability. Primarily, economic challenges including CO 2 capture and transportation costs, carbonated water preparation, etc., and corrosion concerns hinder the large-scale implementation of CWI. Notwithstanding, the findings from the life cycle assessment of CWI suggested the economic viability of CWI and highlighted the importance of adopting the innovative CWI technique to achieve dual objectives of maximizing oil recovery and minimizing environmental footprints in the oil and gas industry. Multiple areas that require further investigation such as investigating the influence of condensable and incondensable contaminants on well integrity and safe CO 2 storage among others were presented.