Coupling a Gas Turbine Bottoming Cycle Using CO2 as the Working Fluid with a Gas Cycle: Exergy Analysis Considering Combustion Chamber Steam Injection
Seyed Hamed Fatemi Alavi, Amirreza Javaherian, S.M.S. Mahmoudi, Saeed Soltani, Marc A. Rosen
Abstract
Gas turbine power plants have important roles in the global power generation market. This paper, for the first time, thermodynamically examines the impact of steam injection for a combined cycle, including a gas turbine cycle with a two-stage turbine and carbon dioxide recompression. The combined cycle is compared with the simple case without steam injection. Steam injection’s impact was observed on important parameters such as energy efficiency, exergy efficiency, and output power. It is revealed that the steam injection reduced exergy destruction in components compared to the simple case. The efficiencies for both cases were obtained. The energy and exergy efficiencies, respectively, were found to be 30.4% and 29.4% for the simple case, and 35.3% and 34.1% for the case with steam injection. Also, incorporating steam injection reduced the emissions of carbon dioxide.