Integrated Gasification Combined Cycle (IGCC) is the type of power technology particularly favorable for plant retrofitting so that carbon dioxide can be removed at a convenient stage of the process [1]. Various options analyzed in the literature concerning this integration are described in [2–4]: pre-combustion with a retrofitting of the power station; post-combustion with a low pressure separation before the stack in a ‘‘end of pipe’’ separation process; decarbonization of the fuel by producing hydrogen, methanol or ammonia; modified cycle with oxycombustion O2/CO2 cycle. We focus in this paper on a CO2 separation in order to integrate this option in the power station cycle, upstream the gas turbine. The CO2 removal requires the addition of two main units: a CO into CO2 shift conversion unit downstream of the gas dedusting system and a CO2 separation and compression unit meeting the transport conditions. A former comparison study, of the existing industrial process led to the choice of the methanol process for carbon dioxide removal [5].