feasibility of using hydrocarbon mixtures as refrigerants in domestic and commercial refrigeration appliances

ozone depleting and warming potential of cfc and hcfc refrigerants led the developed countries to agree on montreal protocol, according to which the production and consumption of these substances must be prohibited before 2010. in this relation, a great number of efforts has been taken to find suitable substitutes for ozone depleting substances (ods). r-134a, which is a hfc, has been found to be an optimum solution for short time substitution. unfortunately, the global warming potential (gwp) of this gas is much more than cfcs.

several research projects have shown that hydrocarbons such as propane, butane, and isobutene are very good substitutes for cfcs. these natural refrigerants have zero ozone depleting potential and negligible gwp. in this paper, the possibility of using hcs as substitutes for cfcs has been investigated, and a computer simulation of a small refrigeration cycle with various refrigerants has been made by use of a revised version of gcap. the results show that a hydrocarbon mixture with 40% propane (r-290), 50% butane (r-600) and 10% i-butane (r-600a) is the most suitable alternative refrigerant with the best performance among all other hydrocarbon mixtures investigated.