continuous belt dryer machine spray dryer milk powder commercial freeze dryer

Work Principle

Continuous belt dryer is specially designed for drying different shapes of root vegetables and leafy vegetables. This drying machine has three-layer and five-layer structure, each layer can be independently adjusted the drying temperature according to the characteristics of the materials.
The working principle of this multilayer conveyor dryer shows as follows: the material is limit controlled by the hopper and is evenly spread on the mesh belt. The materials are driven by the motor to the top layer, then perform uniform motion in the multilayer belt dryer and conduct downward movement layer by layer. Cold air enters from the two axial flow fans, after ballasting via baffle plate, it will flows from bottom to top. There is equipped with a heater under the mesh belt at each layer. The cold air is constantly gradient heated, and then through the material layer. It will conduct mass transfer and heat transfer with the material layer, so that the moisture contained in the material can be rapidly vaporized and evaporated. When the cold air gets to the top layer, it has become saturated moist air, and will be discharged outdoors under the action of exhaust fan.

Working Principle

Products are put on the conveying belt. The belt is made of stainless steel screen and is fixed on the brace rod. Stainless steel baffler plates are also furnished at both sides of the belt to prevent leakage of the products. Belt will be moved inside the dryer by motor. Belt dryer is composed of several independent heating zones which could be further divided into two or more drying sections with different air volume, heat exchange area and air-passing mode.

In the first section, circulation air speed and temperature should be higher with bigger heat exchange area, and air will be passed through products from down to up because in the 1st section, the product has large moisture content and is heavy. The second section is for drying products with less moisture content and weight.In this section, hot air will be passed from up to down. The temperature of each zone will be automatically controlled. Products will be collected by hopper after belt dryer and will be discharged by screw discharger.