Advanced exergetic analysis of a refrigeration system for liquefaction of natural gas

During the last years the total cost of LNG technology has decreased significantly due to improvements of the liquefaction process. However, many liquefaction plants that are still in operation use a three-cascade refrigeration system. In this paper, an advanced exergetic analysis is applied to better understand the operation of a three-cascade refrigeration system for liquefaction of natural gas. In an advanced exergetic analysis, the exergy destruction within a plant component is split into its endogenous/exogenous and unavoidable/avoidable parts. With the aid of this analysis, the potential for improving the thermodynamic efficiency of components and the overall system as well as the interactions among components and their effect on the exergy destruction within each component are estimated. This paper demonstrates some capabilities associated with an advanced exergetic analysis.