Subterranean containment and long-term storage of carbon dioxide in unused aquifers and in depleted natural gas reservoirs

Abstract

There exist huge volumes of unused aquifers in the earth due to high salinity of the groundwater. Deep aquifers can contain large amount of CO 2 in the form of compressed gas, liquid or aqueous solution under high formation pressure. Natural gas dissolved in saline groundwater is exploited in some areas in Japan. A preliminary technical and economic survey on the CO 2 injection system suggests favorable results. More investigations are necessary for assessment of the effect of CO 2 injection on groundwater environment.