INEOS plans to transform the Nini oil field in the North Sea into a carbon storage site. The company aims to inject liquefied CO2 into depleted oil reservoirs beneath the seabed.
To remain in a liquid state CO2 needs to be kept under several hundred PSI of pressure and kept fairly cool. Even at only 40F CO2 boils at about 550 PSIG. In above ground tanks you need to worry about elevated ambient temperatures and if that CO2 tank gets to be over about 88F then that CO2 just straight up can’t be liquified. Above 88F you suddenly have a tank of supercritical CO2 which gets a bit more interesting to store for various reasons.
The deep ocean it actually a fairly ideal place to store liquid CO2 because it is cold and already under an immense amount of pressure.
To remain in a liquid state CO2 needs to be kept under several hundred PSI of pressure and kept fairly cool. Even at only 40F CO2 boils at about 550 PSIG. In above ground tanks you need to worry about elevated ambient temperatures and if that CO2 tank gets to be over about 88F then that CO2 just straight up can’t be liquified. Above 88F you suddenly have a tank of supercritical CO2 which gets a bit more interesting to store for various reasons.
The deep ocean it actually a fairly ideal place to store liquid CO2 because it is cold and already under an immense amount of pressure.