Chemical looping combustion-driven cooling and power cogeneration system with LNG cold energy utilization: Exergoeconomic analysis and three-objective optimization

Abstract

This study conducts thermodynamic and exergoeconomic analyses for a novel chemical looping combustion-driven cooling and power cogeneration system consisting of a supercritical carbon dioxide cycle, an air cycle, an organic Rankine cycle, and a liquid natural gas regasification process. Comprehensive parametric analyses are performed to investigate the impact of design variables on the proposed system's performance metrics, including electrical efficiency (ηel), exergy efficiency (ηex), and total product unit cost (cp,tot). A three-objective optimization is implemented to obtain the optimal system performance. The results underscore that the two reactors exhibit the highest exergy destruction of 17.29 MW, followed by the condenser's exergy destruction of 6.50 MW. The two reactors, expander, gas turbine, and condenser are the most important components within the system, and evaporator 1 and condenser need to be given more attention from exergoeconomic aspects. An optimum split ratio exists to maximize system performance by optimizing the conditions of the recycled stream into the fuel reactor. Optimization results reveal that ηel, ηex, and cp,tot cannot be simultaneously optimal and are 52.68%, 40.72%, and 27.43 $/GJ, respectively, after weighing. Moreover, the weighed performance of the proposed system outperforms those of similar systems despite employing components with lower design efficiencies.