Advanced exergy and exergoeconomic analyses of a hydrogen liquefaction plant equipped with mixed refrigerant system

Advanced exergy and exergoeconomic analyses are applied to a hydrogen liquefaction process. These analyses provide information about the origin of irreversibility and also determine the amount of avoidable irreversibility of the system. Results of the advanced exergy analysis show that in all components except turbo expanders, most of the irreversibility is due to the endogenous exergy destruction. It also indicates that most of the exergy destruction is unavoidable, but there is still a huge potential to improve the performance of the system. Results of advanced exergoeconomic analysis reveal that in terms of avoidable endogenous exergy destruction cost rate, HE-5 and HE-3 heat exchangers should be modified first, because their avoidable endogenous exergy destruction cost rate is higher than that of other components. Also, based on advanced exergoeconomic results, three different strategies are suggested to improve the performance of the components. Finally, a sensitivity analysis is performed on the key parameters of the system to show their effects on the exergoeconomic performance of the plant.