The Mathematical Method and Thermodynamic Approaches to Design Multi-Component Refrigeration used in Cryogenic Process Part II: Optimal Arrangement

A refrigeration cycle is a chain of various pieces of equipment including compressors, condensers, evaporators, and expansion devices each of which takes on a particular thermodynamic process duty in the cycle that eventually results in the production of the required refrigeration. The results of optimized mixed refrigerant cycles (MRCs) in Part I show that the configuration of MRC is an effective parameter in power consumption. In spite of simplicity of MRCs machinery configuration in comparison with a conventional cascade cycle, it is possible to imagine different configurations, providing the process required refrigeration, for these cycles. But the question here is how to find a configuration taking advantage of the existing complicated interactions between low temperature process and refrigeration cycle so that the maximum efficiency and the best functionality will be guaranteed. In this paper, based on the success of the systematic method proposed in part I for the optimal selection of refrigerant composition and operating pressures, the method is extended to give optimal arrangement of the cycle components. An illustrative example is presented to show how the proposed method can be utilized in order to achieve the optimal MRC configuration.