Study on generator for ice slurry using the pressure shift feezing method.

Owing to its good flowability and large latent heat of fusion, ice slurry, which is a mixture of fine ice particles and liquid water, is utilized in ice storage systems. Ice slurry has attracted much attention in recent times for use as a direct-contact coolant, including as a cold source for air-conditioning. There is the particular expectation of the development of biocompatible ice slurry for use in the medical field. However, the generation of biocompatible ice slurry by the conventional method using low-concentration sodium chloride solution is difficult. In the present study, we generated ice slurry by the method of pressure shift freezing, which is based on the freezing-point depression of an aqueous solution under high-pressure conditions. To determine the basic characteristics of the sequential ice slurry generator, experimental investigations were conducted in which different aqueous solutions were used as the test fluid. We successfully established the basic characteristic of the ice slurry generator. Moreover, the physical properties of the ice slurry indicated that the shape of the ice particles in the ice slurry was significantly determined by both the degree of supercooling and the salinity. The relationship between the ice packing factor and the degree of supercooling is discussed in detail.