Comparative thermoeconomic optimization and exergoenvironmental analysis of an ejector refrigeration cycle integrated with a cogeneration system utilizing waste exhaust heat recovery

Two cogeneration cycles based on gas turbines have been compared by means of thermoeconomic and environmental analyses. The analyzed cogeneration systems are gas turbine, organic Rankine cycle (GT + ORC) and an integrated system including gas turbine, organic Rankine cycle, and ejector refrigeration cycle (GT + ORC + ERC). This work has focused on environmental considerations and thermoeconomic evaluation to decrease destruction cost and environmental impacts. The examination of cycles is conducted from energy, exergy, exergoeconomic, and exergoenvironmental (4E) perspectives. A computer MATLAB program is used to generate the simulation results, and the REFPROP 9.1 database is utilized to get thermodynamic properties of the working fluids. The use of the refrigeration evaporator in GT + ORC + ERC increased energy and exergy efficiencies. Multi-objective optimization results indicate that the waste heat utilization in the trigeneration system is more effective in all aspects. In optimal conditions, the exergy efficiency and destruction cost of the GT + ORC + ERC system reached 40.76% and 151.95$ h(-1), respectively. Moreover, optimization is performed by means of energy efficiency and destruction environmental impact as objective functions, and the optimum values are obtained at 30.67% and 46,918.30 mpts h(-1), respectively.