Energy and Exergy Analysis and Optimization of a Multigeneration System by Coupling of GT-MHR Reactor, Absorption Refrigeration, Steam Reforming, and HDH Desalination Cycles

In this paper, a novel multi-generation system based on gas turbine-modular helium reactor cycle is presented. Integrated system consists of a Gas turbine-modular helium reactor cycle as a base cycle and from the combination of subsystems, hydrogen production, absorption refrigeration cycle, and desalination system. Thermodynamic comprehensive modeling (energy and exergy) was done on the suggested system. The effect of various system parameters, such as turbine inlet temperature, compressor pressure ratio, carbon dioxide to methane molar ratio, vapor generator temperature, and mass flow rate of the desalination system have been evaluated on the overall performance of the system. Also, optimization of the overall system using single and multi-objective optimization method has been investigated in terms of energy and exergy compared to the base case. The results showed that the maximum net power output and the energy efficiency and exergy of the overall system in compressor pressure ratio between 2.3-2.45 were 275 MW, 72.05%, and 49.35%, respectively, and with increasing turbine inlet temperature, heat production rate and energy and exergy efficiencies of overall system increases and the cooling production rate and freshwater decreases. In addition, the optimal point of the mass flow ratio of the desalination system for the energy and exergy efficiencies of overall system is 2.857. According to the results obtained in the multi-objective optimization method, the energy and exergy efficiencies of overall system were 74.41% and 50.21%, respectively, and exergy destruction has been reduced to 0.74% compared to base case.