Material to be dried enters the dryer, and as the dryer rotates, the material is lifted up by a series of internal fins lining the inner wall of the dryer. When the material gets high enough to roll back off the fins, it falls back down to the bottom of the dryer, passing through the hot gas stream as it falls. This gas stream can either be moving toward the discharge end from the feed end (known as co-current flow), or toward the feed end from the discharge end (known as counter-current flow). The gas stream can be made up of a mixture of air and combustion gases from a burner, in which case the dryer is called a direct heated dryer. Alternatively, the gas stream may consist of air or another (sometimes inert) gas that is preheated. When the gas stream is preheated by some means where burner combustion gases do not enter the dryer, the dryer known as an indirect heated type. Often, indirect heated dryers are used when product contamination is a concern.
Belt dryer is continuous-production drying equipment. The dryer being widely used for drying the piece, strip and particle shape materials in good ventilation. The dryer is suitable for de-watering fruit & vegetable which the moisture content is high and high drying temperature is not allowed. Drying speed of belt dryer is fast, evaporation strength is high and the product quality is good. belt dryer is widely used and support for drying various kind of material such as pigment, fiber, fruit & vegetable, briquette etc.