Performance analyses of oxy-fuel power generation systems including CO2 capture: comparison of two cycles using different recirculation fluids

With increasing concerns on global warming, reduction of CO2 emission has become a hot issue and studies of CO2 capture and storage (CCS) technology in power plant applications are in progress. Oxy-fuel combustion is one of the several available technologies that intend to capture CO2. Since the combustion gas consists mainly of CO2 and H2O in oxy-fuel combustion systems, it is easy to separate CO2 from the flue gas using a simple mechanical method instead of complex chemical processes. There have been suggested a couple of power cycles using different recirculation fluids for combustion dilution purpose. This study aimed to investigate the influence of CO2 capture on the performance of two promising oxy-fuel combustion power cycles adopting H2O and CO2 as the recirculation fluid. Optimal integration between the carbon capture process and the power cycle was examined and the influences of carbon capture on the entire system performance were compared for the two cycles.