Perpustakaan Digital ITB

CO2 storage in deep saline aquifers is a key Carbon Capture and Storage (CCS) option for reducing atmospheric emissions. Injection rate is a central parameter, governing both reservoir pressure buildup, CO2 dissolution rate, and trade-off between storage efficiency and trapping efficiency that remains poorly understood in heterogeneous aquifers. This study evaluates how storage design parameters affect CO2 migration and trapping, examines the coupled effect of injection rate on pressure buildup and CO2 dissolution rate, and identifies the optimum storage efficiency for a heterogeneous saline aquifer. A 3D reservoir model was simulated in tNavigator, with CO2STORE keywords, over 2 years of injection and 100 years of monitoring, covering sensitivity study of perforation placement, well spacing, injection rate, and injection mode, followed by an optimization study from 43-144 MMSCFD per field. Bottom perforation and adequate well spacing improved trapping by extending CO2-brine contact and avoiding plume commingle, while injection mode had little effect. Pressure buildup increased almost linearly with injection rate, while dissolution rate gains flattened at higher rates, leaving more CO2 mobile. Storage efficiency increased from 0.39% to 1.16% as trapping efficiency decreased from 94.97% to 90.54%. An injection rate of 100 MMSCFD/field was identified as optimum, with 0.84% storage efficiency and 93.18% trapping efficiency.