Recently, the petroleum industry has been facing challenges to develop and operate fields with high CO2 contents. In the case of many Brazilian pre-salt fields (e.g. Libra, Jupiter, Lula, among others), huge volumes of associated gas with significant CO2 molar fractions are produced at high pressures and need to be handled by the offshore systems. After separation from the natural gas, a CO2-rich stream can be compressed and re-injected for Enhanced Oil Recovery (EOR) into the reservoir (even in cases where oil recovery increase is not significant, venting to the atmosphere is usually avoided for HSE reasons). The separation and compression may be performed topside or subsea. In either case, a further increase in CO2 content may occur in the production streams with field life time.