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

Abstract

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 À1 , 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 À1 , respectively.

Thermodynamic Comparison of the Steam Ejectors Integrated at Different Locations in Cogeneration Systems

“…Cao et al [31] proposed a cogeneration system integrated with an ORC and a steam ejector, the thermal efficiency of which reached 79.0%. Fazali et al [32] observed that the exergy efficiency of an integrated system, including gas turbine, ORC, and ejector could reach 40.76%. Zhang et al [33] designed a novel cascade system based on a steam ejector and high-back-pressure technology, and the heating capacity increased by 4.21%.…”

Comparative exergetic sustainability analysis of subcritical and supercritical organic Rankine cycle plants for a waste heat recovery application

“…Additionally, Maruf et al 24 demonstrated the applicability of the exergetic sustainability method for the assessment of power generation scenarios at a national level using the situation in Bangladesh as a case study. The exergetic sustainability methodology has also been applied widely in assessing the environmental viability of waste treatment technologies as reported in a systematic literature review study by Soltanian et al 25 Regarding the exergoenvironmental method, Fazeli et al 26 employed an integrated exergy-based environmental assessment to demonstrate the effectiveness of waste heat recovery for multi-generation of energy products in an integrated system comprising a gas turbine, an ORC, and an ejector refrigeration cycle. Talebizadehsardari et al 27 carried out an exergoenvironmental analysis, among other exergy-based assessments, of an integrated energy system involving gas and steam turbines, ORC, and a carbon capture and storage (CCS) facility.…”