It is aimed to simulate a dual-stage Selexol process for removing CO2 as well as H2S from the syngas typically found in the IGCC power plant with a dry-coal fed gasifier. Temperature-dependent Henry's law is employed in the process simulation to estimate the solubilities of gas components in Selexol. The operating conditions of dual-stage Selexol unit were found so as to meet simultaneously various specifications such as 99 + % H2 recovery, 90% or 95% CO2 recovery and 99 + % H2S recovery. The power consumptions for auxiliary units and CO2 compression estimated by the simulation are in good agreement with those reported in the literature . It is shown that the conventional, integrated dual-stage Selexol unit can achieve 95% carbon capture rate as well as 90% by simply changing the operating conditions.