{"title":"Effect of Valve Pressure Drop in Exergy Analysis of C2+ Recovery Plants Refrigeration Cycles","authors":"B. Tirandazi, M. Mehrpooya, A. Vatani","volume":17,"journal":"International Journal of Chemical and Molecular Engineering","pagesStart":66,"pagesEnd":73,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/6249","abstract":"<p>This paper provides an exergy analysis of the multistage refrigeration cycle used for C2+ recovery plant. The behavior of an industrial refrigeration cycle with refrigerant propane has been investigated by the exergy method. A computational model based on the exergy analysis is presented for the investigation of the effects of the valves on the exergy losses, the second law of efficiency, and the coefficient of performance (COP) of a vapor compression refrigeration cycle. The equations of exergy destruction and exergetic efficiency for the main cycle components such as evaporators, condensers, compressors, and expansion valves are developed. The relations for the total exergy destruction in the cycle and the cycle exergetic efficiency are obtained. An ethane recovery unit with its refrigeration cycle has been simulated to prepare the exergy analysis. Using a typical actual work input value; the exergetic efficiency of the refrigeration cycle is determined to be 39.90% indicating a great potential for improvements. The simulation results reveal that the exergetic efficiencies of the heat exchanger and expansion sections get the lowest rank among the other compartments of refrigeration cycle. Refrigeration calculations have been carried out through the analysis of T&ndash;S and P&ndash;H diagrams where coefficient of performance (COP) was obtained as 1.85. The novelty of this article includes the effect and sensitivity analysis of molar flow, pressure drops and temperature on the exergy efficiency and coefficient of performance of the cycle.<\/p>\r\n","references":"[1] Vidal A, Best R, Rivero R, Cervantes J, Analysis of a combined power and refrigeration cycle by the exergy method, Energy 31 (2006) 3401\u00ac3414.\r\n[2] Kotas TJ. The exergy method of thermal plant analysis. Malabar, FL: Krieger Publish Company; 1995.\r\n[3] Kanoglu M, Exergy analysis of multistage cascade refrigeration cycle used for natural gas liquefaction, Int. J. Energy Res 26. (2002), 763-774 \r\n[4] GPSA. 1998. Section 16, Hydrocarbon Recovery (11th ed). Gas Processors Suppliers Association. SI Version.\r\n[5] E Van Wylen and Sonntag, Fundamentals of Classical Thermodynamics,(6th ed), John Wiley & Sons ,(2002)\r\n[6] Khaliq A, Kumar R, Exergy analysis of double effect vapor absorption refrigeration system, Int. J. 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