Comparative Study of New Environmentally Safe Refrigerant Fluids

Abstract

Chlorofluorocarbons (CFCs) and Hydro chlorofluorocarbons (HCFCs) based refrigerants have found widespread uses in home refrigerators, heat pumps, air conditions and chemical industries such as oxygen liquification, this is primarily due to their nontoxic, nonflammable nature and their high overall thermodynamic efficiency. However, (CFCs) and (HCFCs) are character with intermediate to high ozone depletion potential (ODP) and global warming potential (GWP).As a consequence they will be banned during the next two to four decades in accordance with Kyoto and Montreal Protocols. The search for potential substitutes is in progress. Potential substitutes include pure and mixtures of hydro fluorocarbons (HFCs) which have the potential for matching thermodynamic properties of current working fluids while meeting several criteria for ODP, GWP, flammability, toxicity and production cost. This research work is intended to make comparative study between five of the potential substitutes ( R227ea ; R245fa ; R600 ; R410A binary mixture ; R407C Ternary mixture ) and three of the old refrigerants ( R12 ; R22 ; R114) that are used in heat pumps. The comparisons were based on Environmental, Safety and Thermodynamic Criterion. The software of Engineering Equation Solver (EES) and Reference Fluid Properties (REFPROP) were employed to simulate the heat pumps under wide range of operation conditions. The results revealed that all the selected newly refrigerants match the old ones very well in term of safety and thermodynamics, with R227ea, R600 and R245fa giving the highest coefficient of performance (COP) , R410A and R407C providing the highest heating capacity, cooling capacity , and vapor pressure