Enforced Carbon Mineralization: Unlocking CO2 Storage Potential in Saline Aquifers

Abstract CO2 storage in saline aquifers has gained attention due to its promising long-term storage capability. However, the efficiency of long-term CO2 storage depends on various trapping mechanisms that need to be investigated and optimized. Thus, the current study explores the mineralization of CO2 in carbonate formations and investigates the enhancement of mineralization through additives such as strontium chloride (SrCl2), and barium hydroxide (Ba(OH)2). Laboratory-scale testing on carbonate core samples were performed at a pressure and temperature of 1500 psi and 60°C, respectively, using a static reactor cell. Initially, core samples were saturated with synthetic seawater, and CO2 mineralization was evaluated by injecting supercritical CO2. Subsequently, enforced mineralization was examined by introducing additives into the seawater. The tests were performed for 30 days and the influence of the additives on CO2 mineralization was evaluated using core characterization techniques. The additives promoted the mineralization process and were confirmed through the Medical-CT and NMR analysis of the core sample after treatment, which revealed changes in pore structures due to mineral dissolution and precipitation, providing insights into the effectiveness of these additives on reservoir quality. Research findings demonstrate that carbonate saline aquifers accept CO2 storage more efficiently when the additives are included, and support better CO2 storage methods that maximize capacity and achieve sustained reservoir stability. The outcomes of the study provides a better insight into the enhanced carbon mineralization process in saline aquifers by complex interaction between the seawater, injected CO2, additives, and formation. This will lead to the development of better carbon storage techniques for long-term stability in saline aquifers.