| Summary: | Laboratory experiments were performed to measure the supercritical CO<sub>2</sub> (scCO<sub>2</sub>) storage ratio (%) of conglomerate and sandstone in the Janggi Basin, which are classified as rock in Korea that are available for CO<sub>2</sub> storage. The scCO<sub>2</sub> storage capacity was evaluated by direct measurement of the amount of scCO<sub>2</sub> replacing the pore water in each reservoir rock core. The scCO<sub>2</sub> sealing capacity of the cap rock (i.e., tuff and mudstone) was also compared by measuring the scCO<sub>2</sub> capillary entry pressure (Δp) into the rock core. The measured average scCO<sub>2</sub> storage ratio of the conglomerate and the sandstone were 30.7% and 13.1%, respectively, suggesting that the scCO<sub>2</sub> storage capacity was greater than 360,000 metric tons. The scCO<sub>2</sub> capillary entry pressure for the tuff ranged from 15 to 20 bar and for the mudstone it was higher than 150 bar, suggesting that the mudstone layers had enough sealing capacity from the aspect of hydromechanics. From XRF analyses, before and after 90 d of the scCO<sub>2</sub>-water-cap rock reaction, the mudstone and the tuff were investigated to assure their geochemical stability as the cap rock. From the study, the Janggi Basin was considered an optimal CO<sub>2</sub> storage site based on both its high scCO<sub>2</sub> storage ratio and high capillary entry pressure.
|
|---|
