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.
Being adapted the heating way of jacket and inner stirring at the same time, its heat conducting area is large and its heat efficiency is high. Being installed stirring in the machine, it makes raw material in the cylinder form the state of continuous circle inside the cylinder, so the uniformity to be heated of raw material is raised greatly. Being installed stirring apparatus in the machine, pulpiness, pastelike mixture or powder raw materials can be dried easy.