The condensation of the CO 2 -rich stream is facilitated by a single stage mechanical vapour compression refrigeration cycle named "Refrigeration" in Figure . For the refrigeration cycle the key parameters are the isentropic compressor efficiency, the condenser temperature and sub-cooling temperature, the refrigerant evaporator temperature (CO 2 condenser) and the super-heating in A variant that still employs refrigeration cooling and pumping is if a pressure P liq above the critical point, still below the final pressure is specified accompanied by a specified cooling temperature T liq . Obviously, co-existing vapour and liquid is not possible above the critical point, but the CO 2 stream is cooled from the last compression stage into the dense phase region before final pumping to the specified final pressure. A summary of the key simulation parameters is given in Table . Perhaps the most interesting parameters are: the number of compression stages n, and the inclusion of liquefaction at a specified pressure P liq . Further, the choice of compressor cooling temperature T in as well as the magnitude of the pressure drop in each compression stage after/inter-cooler are also of particular interest.