Comparative Study and Optimization of CO2 Capture and Storage in LNG-fired Power Plant
Keywords:CO2 capture and storage, genetic algorithm, LNG cold energy, pareto optimal
In the trends of sustainable development and environmental protection, reducing greenhouse gas emissions and utilizing energy sources are feasible solutions. In this study, Aspen HYSYS-based performance simulations for LNG-fired power plants with CO2 capture and storage using cryogenic and amine technologies were conducted to compare and evaluate. LNG cold energy is employed in liquefied CO2 process. Waste heat from exhaust gas of a gas turbine was powered for steam cycle or stripper column. The results showed that the thermal power generation efficiency of the amine system is lower than that of the cryogenic system, however the excessive gasification of LNG in the MEA system is much lower than that of a cryogenic system. The CO2 mass fraction in recovered liquid of the amine system is also higher than the other one. Multi-objective optimization using genetic algorithm (GA) is then carried out providing a set of optimum solution for investors and operators in balance of the excessive gasification of LNG and CO2 recovery rate.