Fluid ice slurry & heat transfer

Ice slurry is a good cold-carrying and cold-storage medium, as well as a high-efficiency heat exchange medium with good safety and cost-effectiveness. Because of its uniqueness, it has good application prospects in many fields.

Ice slurry is an aqueous slurry of ice crystal particles with an average characteristic diameter of no more than 1 mm, that is, a mixed fluid formed by tiny ice crystals and water (or aqueous solution). Ice crystals have small particle size, large specific surface area, and good flow and heat transfer characteristics. The latent heat value of the ice-water phase change is 334 kJ/kg, so the ice slurry can be used as a heat exchange medium for the cold energy carrier (secondary refrigerant) and as a cold storage medium for cold energy storage. Since the birth of ice slurry technology, it has been recognized internationally as a natural secondary refrigerant due to a series of unique advantages.

Figure 1-Ice crystal

Fluid ice is a new concept of ice that is different from traditional solid ice. It can be a mixture of spherical particles of ice crystals and liquid--Slurry Ice, or there can be small ice crystal particles with a shape and appearance like snow alone. It has the characteristics of fluid and can be transported by pipeline; it also has the characteristics of ice, cooling block and large latent heat.

The slurry ice are very small, smooth and round, and they will enter every corner of the product to be cooled. This enables the fastest heat transfer, immediately and evenly cools the product, and prevents the formation of potentially harmful bacteria, enzyme reactions, and discoloration. Slurry ice can keep peak product freshness longer.

The manufacturing technology of fluid crystal ice is a brand new ice making technology different from the traditional solid ice manufacturing technology. The principle is to cool the salt solution to a certain temperature, so that the water in the solution crystallizes into fine spherical ice crystals and swims in the ionic solution, thereby forming a fluid ice slurry. Under certain conditions, the separation of ice crystals and liquids can be achieved, thereby forming pure solid particulate ice crystals.

Figure 2-Fluid ice slurry

Characteristics of fluid crystal ice:

1. Huge surface (contact) area-3.8 times that of snow flakes;

2. Super heat transfer performance-up to 5 times that of water;

3. Constant temperature can be maintained-through the heat exchanger, it can achieve constant temperature heat exchange on the ice side of the fluid;

4. Extreme cooling and cooling.

Shenshi tube-in-tube heat exchanger has strong refrigeration heat exchange capacity and high reliability. It is used as a condenser in a fluid ice slurry system.

Figure 3-Sunwell fluid ice slurry system