Fluidized bed dryer (also called fluid bed dryer) is equipment used extensively in the bulk industry to reduce the moisture content of powder and granules. The equipment works on a principle of fluidization of the feed materials.
In the fluidization process, hot air is introduced at high pressure through a perforated bed plate. The wet solids are lifted from the bed plate and suspended in a stream of air (fluidized state). Heat transfer is accomplished by direct contact between the wet solid and the hot supply air. The vaporized liquid is carried away by the exhaust gasses.