Formation conditions of clathrates between HFC alternative refrigerants and water

• Published in: International journal of thermophysics Vol. 20; no. 6; pp. 1753 - 1763
• Main Authors: AKIYA, T, SHIMAZAKI, T, OOWA, M, MATSUO, M, YOSHIDA, Y
• Format: Conference Proceeding Journal Article
• Language: English
• Published: New York, NY Springer 01.11.1999
• Subjects: Applied sciences; Decomposition; Energy; Energy. Thermal use of fuels; Evaporation; Exact sciences and technology; Industrial refrigeration; Mixtures; Phase diagrams; Pressure; Refrigerants; Refrigerating engineering; Refrigerating engineering. Cryogenics. Food conservation; Temperature; Water; Air conditioning; Refrigeration cycle; Decomposition temperature; Clathrate; Critical point; Experimental study; Formation mechanism; Refrigerant fluid
• ISSN: 0195-928X; 1572-9567
• DOI: 10.1023/A:1022614114505

There are two promising candidates as alternative refrigerants for air-conditioners and heat pumps. The first is R407C, which is composed of HFC-32 (23 mass%), HFC-125 (25 mass%), and HFC-134a (52 mass%). The second is R410A, which is composed of HFC-32 (50 mass%) and HFC-125 (50 mass%). In this study, formation conditions of clathrate compounds between water and HFC alternative refrigerants such as HFC-32, HFC-125, HFC-134a, and their mixtures, R407C and R410A, were investigated. Phase diagrams of clathrates of these HFC alternative refrigerants and their mixtures were determined. From the phase diagrams, the critical decomposition temperature and the critical decomposition pressure were determined. The relationship between the critical decomposition points for the clathrates of HFC-32, HFC-125, HFC-134a, R410A, and R407C were studied. It is found that R407C and R410A form clathrate compounds with water under the evaporating temperature condition in the refrigeration cycle of air-conditioners and heat pumps.