Phase equilibria of some alternative refrigerants hydrates and their mixtures using for cool storage materials

Electric power demand for residential air-conditioning has been increasing in Japan. Development of cool storage systems which shifts this demand to off-peak period and contributes to the load leveling of power generation is necessary. The hydrate cool storage system is the suitable cool storage system because its cool storage density is large and chiller efficiency is high. In this study, alternative refrigerants HFC-32(CH/sub 2/F/sub 2/), HFC-125(C/sub 3/CHF/sub 2/) gas hydrate and their mixture were selected for cool storage materials. The phase equilibria of these alternative refrigerants gas hydrates and its mixtures were obtained. From these phase equilibria, the critical decomposition temperature, the critical decomposition pressure and the heat of formation of these gas hydrates were determined.