Abstract
It is studied about a new strategy for the CO_2 sequestration. In this method, CO_2 is injected into a seabed, sediments under the seabed. CO_2 hydrate is one of stable phase in environment of seabed. The injected CO_2 can form the hydrate in a diffusion process under the seabed, resulting in a roofed seal-layer. A large amount of liquid CO_2 will be kept under the seal layer. The present article reports about an experimental study of a CO_2 permeability through the sediments with CO_2 clathrate hydrate. The permeability was measured at about 3, 6℃ and at about 7, 10MPa with different amount of water in a system. It was clarified that the sealing ability of the hydrate-layer was not affected by temperature and pressure condition so much, and depended on the total amount of water in the artificial sediments.
