Method and system for carbon dioxide energy storage in a power generation system
A CO2 energy storage system includes a storage tank that stores a CO2 slurry, including dry ice and liquid CO2, at CO2 triple point temperature and pressure conditions. The storage system also includes a first pump coupled in flow communication with the storage tank. The first pump is configured to receive the CO2 slurry from the storage tank and to increase a pressure of the CO2 slurry to a pressure above the CO2 triple point pressure. The energy storage system further includes a contactor coupled in flow communication with the first pump. The contactor is configured to receive the high pressure CO2 slurry from the pump and to receive a first flow of gaseous CO2 at a pressure above the CO2 triple point pressure. The gaseous CO2 is contacted and then condensed by the melting dry ice in the slurry to generate liquid CO2.