The condenser is essential in CO2 recirculation. The condenser is a piece of apparatus or equipment that can be used to condense, that is, to change the physical state of a substance from its gaseous to its liquid state. We use double pipe configuration in small systems (up to 48 liter) and shell and pipe configuration for industrial. We do not use plate exchanger as they clog easily and cannot resist to standard CO2 pressure.
The condenser is an important part of the extraction system as, without it, it cannot be possible to recirculate the CO2.
In fact, all along the process, CO2 continuously changes its status: first liquid, then supercritical, then gaseous and finally back liquid again. Here on the right see all the changes, step by step. Colors: Blue = Liquid CO2, Green = Supercritical CO2, Yellow = Gaseous CO2.
When the gaseous CO2 comes out from the separators, the CO2 is completely clean and can travel to the condenser and, after that, to the Reservoir, where the Liquid CO2 is stored, waiting to be pumped again in the circuit.