Techno-economic Optimization of the Combined Supercritical Carbon Dioxide and Air Brayton Cycles Driven by Copper-Based Chemical Looping Combustion

Abstract

The chemical looping combustion (CLC)-driven power generation system has great potential for application. In this study, a direct CLC-driven combined supercritical carbon dioxide and air Brayton cycle with near-zero carbon emissions (CLC–sCO2–BC) is proposed. After revealing the thermodynamic performance advantages of the proposed system, we comprehensively compared the thermoeconomic performance of CLC–sCO2–BC with and without preheating and optimized the performance of the two layouts using an immune genetic algorithm. The results show that the proposed system has a net power advantage of 1.15 MW and an efficiency gain of 2.30 percentage points compared to the Allam-Z cycle. The preheating mode can enhance the thermoeconomic performance of the proposed system by increasing the temperature of recycled CO2 in the fuel reactor. The optimization results confirm that the preheated layout achieves a thermal efficiency improvement of 2.78 percentage points and a levelized cost of electricity reduction of $7.35/MWh over the basic layout. Meanwhile, the preheated layout lowers the optimal gas turbine inlet temperature and increases the optimal CO2 compressor inlet pressure.