Role of R22 in Refrigerating and Air Conditioning Equipment

摘要

The U. S. Environmental Protection Agency has recently performed an analysis that shows the need for nearly 100% worldwide-acceptance of total CFC phase out. The adoption of HFCs (for example R134a) and HCFCs (for example R123 and R22) alternatives, at least in the interim, is the only feasible means by which this schedule can be met. In the past four years, there has been more research for the adaption of R134a and R123 to R12 and R11 systems than ever in the history of the refrigeration industry. Refrigerant properties measurements, materials compatibility studies, and hardware and system design changes have been conducted worldwide with information exchanged between countries on almost a daily basis. Even so, some previously unforeseen problems persist so that the system design for virtually any application is not yet final, and for some applications system design solutions are not even in sight. Tried and proven R22 systems are being extended to temperature and capacity ranges beyond their usual application to fill in these gaps; for example, for food refrigeraion systems. Manufacturers in developed countries need alternatives and strategies that they can depend on before investing in the development of new products and equipment necessary for the CFC phase out. It is not likely that industry will make the large investments necessary to produce new equipment until new refrigerants are proven acceptable and are known to be available in adequate quantity for use. Developing countries need viable alternatives to combat a natural reluctance to participate in the CFC phase out in order to improve their standards of living. They cannot afford the risk or economic impact of a refrigeration systems that are unproven or not in adequate supply. Thus, the HCFC and HFC refrigerants represent the only interim solution known today.