Closed cycle spray drying system is working in a confined environment; the drying medium is generally inert gas has a protective effect on the material. It is suitable for drying materials with organic solvents, materials with poisonous gas, and materials that are easy to oxidize during drying. This process uses nitrogen as a recycle gas to protect the dry material. Nitrogen needs to undergo the dust removal and condensation process, condensed nitrogen is heated to the desired temperature through the plate heat exchanger, then into the drying tower to dry the material again. In order to control the efficiency and quality of material drying, the key is whether the heating temperature of nitrogen is accurate. Grano's plate heat exchanger has high heat transfer efficiency and precise temperature control, which can greatly improve the quality of drying.
Plate heat exchanger is widely used in the food industry, with ice cream as the representative product. The production of ice cream mainly includes steps such as the mixing of the mixture of sterilizing and cooling, the filling and packing of ice cream. Before into the homogenizer, ice cream mixed material needs to be strictly controlled between 65℃ ~70℃ through the plate heat exchanger. When the temperature is too low, fat is easy to be condensed; when too high, the material is prone to have hot stink. And then before into the aging tank, use the plate heat exchanger for sterilization, and make the material temperature up to the aging of the required temperature. Make heating and sterilization done at the same time to save cost. Ice cream material is relatively viscous, Grano's BNF series of the plate heat exchanger with wide flow path, and high heat transfer efficiency, can be a good choice for this heat transfer work.