[HSC07-16] Experimental Study on Sealing Mechanism of CO2 Hydrate during Carbon Dioxide Storage in Subseabed
Keywords:Storage in Subseabed, CO2 Hydrate, Sealing function
In this study, we investigate experimentally whether CO2 hydrate exhibits the sealing function as a cap rock by injecting liquid CO2 and forming CO2 hydrate in Toyoura sand enclosed in a core holder that reproduces subseabed pressure and temperature conditions. When liquid CO2 was injected at the same speed as buoyancy under the condition mimicking the 600 m water depth and the 150 m sediment depth below the seafloor, temperature increase indicating the formation of CO2 hydrate was observed about 36 hours after the start of injection. After confirming the formation of CO2 hydrate, liquid CO2 was injected again. We observed rapid pressure increase near the inlet of the core which means the pore clogging due to the CO2 hydrate formation.