Structural and Parametric Investigations of Oxy-Fuel Combustion Cycles with the Aim of Increasing Efficiency of Electricity Production

Abstract

This study aims to present the results of thermodynamic analysis and optimization of the E-MATIANT cycle. The design parameters of the cycle are set up on the basis of the component technologies of today's state-of-the-art gas turbines with a turbine inlet temperature between 1100°C and 1700°C. The optimal pressure ratio ranges for the considered turbine inlet temperatures are identified and a comparison with existing evaluations is made. For the optimal initial parameters E-MATIANT net efficiency varies from 42.0 to 49.8% without considering turbine cooling. An influence of additional reheat in combustor chamber on cycle efficiency was identified. Two turbine cooling schemes are proposed. The maximum net efficiency of E-MATIANT cycle, which is equal to 44.0%, is obtained for turbine inlet temperature equal to 1400°C and turbine inlet pressure equal to 40 bar taking into account turbine cooling. An influence of water injection in coolant flow on cycle efficiency was estimated. The performance penalty due to the oxygen production and carbon dioxide capture is examined.