Study on retaining natural refrigerant in seafood processing industries in India

In the seafood processing sector in India, natural refrigerant such as NH3 is currently replaced by Freon refrigerants such as HFC-404A, because these systems are comparably more compact, operate above atmospheric pressure and are less toxic. However, these synthetic refrigerants are one of the major sources of global warming. This paper focuses on a standalone-CO2 system with a multi-ejector for transcritical operation and an NH3-CO2 cascade system considering the climatic conditions of important coastlines covering the majority of catch in India. The annual coefficient of performance is compared, and the results show that the COP of NH3-CO2 cascade system exceeds the HFC-404A system by 35 %. Cascade system performs better for -40 oC deep freezers, and the standalone-CO2 system with heat recovery can be efficiently used for -18 oC cold storage. This study will aid in the retention of natural refrigerants in many seafood cities of India. Keywords: ammonia, carbon dioxide, natural refrigerant, cascade, seafood processing