Numerical simulations of CO 2 -hydrate formation in laboratory-scale sand sediment

CO 2 capture and storage is one of the effective countermeasures against global warming and sub-seabed geological storage of CO 2 in the form of gas hydrate is an attractive option for CCS because gas hydrate can stably exit in low-temperature and high-pressure condition and the risk of CO 2 leakage may be lower than the other CCS methods. For the effective design of storage system, it is necessary to model the formation of CO 2 -hydrate. In this study, a CO 2 -hydrate formation model in porous media was proposed and applied to two different types of formation — one is the hydrate formation in sand sediment without flow and the other is that in gas-water two-phase flow in sand sediment. Numerical studies, which simulated the experimental conditions of previous study, were conducted and formation behaviors of CO 2 -hydrate in sand sediment were revealed.