Refrigerant mixtures comprising tetrafluoropropene, difluoromethane, pentafluoroethane, and tetrafluoroethane, and uses thereof

#The present disclosure relates to compositions for use in refrigeration systems. In particular these compositions are useful in processes for producing cooling, methods for replacing refrigerants, and refrigeration apparatuses.

#The refrigeration industry has been working for the past few decades to find replacement refrigerants for existing refrigerants including ozone-depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). These existing refrigerants are being phased out as a result of the Montreal Protocol. The solution for most refrigerant producers has been the commercialization of hydrofluorocarbon (HFC) refrigerants. Some new HFC refrigerants have zero ozone depletion potential and are therefore not currently subject to the Montreal Protocol phase-out.

#Further environmental regulations, however, may ultimately cause global phase out of some of these HFC refrigerants due to their global warming potential (GWP). Currently, industry is facing regulations relating to GWPs for refrigerants used in mobile air-conditioning systems. If the regulations are more broadly applied in the future, for instance to stationary air conditioning and refrigeration systems, an even greater need will be felt for refrigerants that can be used in all areas of the refrigeration and air-conditioning industry. Uncertainty as to the ultimate regulatory requirements relative to GWP has forced the industry to consider multiple candidate compounds and mixtures.

#Before addressing details of embodiments described below, some terms are defined or clarified.

#As used herein, the term heat transfer fluid includes a composition used to carry heat from a heat source to a heat sink.

#A heat source includes any space, location, object, or body from which it is desirable to add, transfer, move, or remove heat. Examples of heat sources include spaces (open or enclosed) requiring refrigeration or cooling, such as refrigerator or freezer cases in a supermarket, transport refrigerated containers, building spaces requiring air conditioning, industrial water chillers, and the passenger compartment of an automobile requiring air conditioning. In some examples, the heat transfer fluid may remain in a constant state throughout the transfer process (e.g., not evaporate or condense). In other examples, evaporative cooling processes may utilize heat transfer fluids, as well.