Can CO ₂ hydrate assist in the underground storage of carbon dioxide?

Abstract

Abstract The sequestration of CO 2 in the deep geosphere is one potential method for reducing anthropogenic emissions to the atmosphere without necessarily incurring a significant change in our energy-producing technologies. Containment of CO 2 as a liquid and an associated hydrate phase, under cool conditions, offers an alternative underground storage approach compared with conventional supercritical CO 2 storage at higher temperatures. We briefly describe conventional approaches to underground storage, review possible approaches for using CO 2 hydrate in CO 2 storage generally, and comment on the important role CO 2 hydrate could play in underground storage. Cool underground storage appears to offer certain advantages in terms of physical, chemical and mineralogical processes, which may usefully enhance trapping of the stored CO 2 . This approach also appears to be potentially applicable to large areas of sub-seabed sediments offshore Western Europe.