Abstract
CO_2 ocean storage is one of greenhouse gas control technologies. This paper describes the formation and dissolution of CO_2 hydrate films on the surface of liquid CO_2 for CO_2 ocean storage. The induction time for the formation of the hydrate films was decreased with an increase in subcooling. A thick layer including CO_2 hydrate films was formed by removal and re-formation process of the hydrate films due to disturbing of the interface between water and liquid CO_2. The dissolution rate of CO_2 hydrate films was obtained from dissolution experiments of CO_2 drops covered with the hydrate films under water-flow conditions. The experimental dissolution rate was smaller than that predicted form a theoretical model with mass transfer coefficient from Ranz-Marshall's equation.
