Characteristics and optimization of supercritical CO2 recompression power cycle and the influence of pinch point temperature difference of recuperators

Supercritical carbon dioxide (S-CO2) power cycle has been under the spotlight for years as one of the promising solutions to resolve the energy and environmental problem. The most of previous studies focused on cycle performances and applicable configuration. In this study, detailed and extensive analysis on the recompression S-CO2 power cycle was carried out to reflect more practical and desirable conditions. This study focused on the optimization of the S-CO2 cycle by evaluation of the irreversibility of the recuperators using the effectiveness analysis and pinch point temperature difference (PPTD) analysis. Split ratio from the main stream to the recompressor and compression ratio were considered as independent parameters. From the simulation, the characteristics and performance of the recompression cycle were discussed. The optimum operating conditions were determined in combinations of PPTDs of the two recuperators. With the performance curves, control strategy of the two independent parameters is ranged for desirable operation of S-CO2 power cycle.