new approach for design and optimization of refrigeration systems

In this study, a new approach for design and optimization of refrigeration systems was developed using both combined pinch and exergy analysis (cpea) technique and mathematical programming# in this regard, new diagrams of omega composite curves (occ) and omega grand composite curve (ogcc) were applied for thermal exergy analysis of heat exchanger network# also, ω-h diagram was used to compute all the thermal, mechanical, and chemical exergy losses within the process# as a result, using occ, ogcc and ω–h diagrams, the exergy losses of all unit operations in processes was calculated# then, the diagrams were combined with mathematical programming to propose a new systematic procedure for design and optimization of sub-ambient processes# a case study of natural gas liquefaction process was used to demonstrate the application of the proposed procedure# in this case study optimization of the lng process resulted in 24#9% lower shaft work consumption#