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.