Belt dryers are now divided into single-layer and multi-layer types, but the operating principle is the same. The material in the hopper of the belt dryer is evenly spread on the mesh belt by the feeder, and moves forward with the conveyor belt. The hot air in the drying unit passes vertically through the material layer to dehydrate the material.

The thickness of the material layer on the mesh belt is confirmed based on factors such as material properties, fabric method, and drying temperature, and is generally adjusted within the range of 20-100mm. The mesh belt is made of 12-60 mesh stainless steel, and three-dimensional mesh belts can also be selected as needed. Dragged by the transmission device to move inside the dryer. The drying section consists of several units, with each unit independently circulating hot air. Some of the exhaust gas is discharged by a dedicated dehumidification fan, and the exhaust gas volume of each unit is controlled by a regulating valve. In the previous cycle unit, the hot air from the circulating fan enters the lower chamber of the unit through the side air duct. The airflow is heated by the heat exchanger and distributed by the distributor, forming a jet flow that blows towards the mesh belt, passes through the material, and enters the upper chamber. The drying process of a belt dryer involves hot air passing through the material layer to complete the heat transfer process.

The upper chamber is connected to the fan through a duct, and most of the gas circulates. A portion of the gas with lower temperature and higher moisture content is discharged as exhaust gas through the dehumidification pipe, regulating valve, and dehumidification fan. In the lower circulation unit, the air from the circulating fan first enters the upper chamber, is heated by the heat exchanger, passes through the material layer, and enters the lower chamber. The lower chamber is connected to the fan inlet through a side air duct and a return air duct, and most of the gas circulates while a portion is discharged. The upper and lower loop units can be flexibly equipped according to user needs, and the number of units can also be selected as needed.