Product Center

DW Series Belt Dryer

Overview
The DW series belt dryer is a commonly used continuous drying equipment, widely applicable in chemical, food, pharmaceutical, building materials, electronics and other industries. It is suitable for drying sheet-like, strip-like, and granular materials with good permeability. It is particularly suitable for materials with high moisture content and low permissible temperature, such as dehydrated vegetables and Chinese herbal medicine slices. The DW series belt dryer has the advantages of fast drying speed, high evaporation intensity, and good product quality. For pasty materials from dewatering filter cakes, drying can be performed after shaping by a granulator or extruder.

Principle and Features
Materials in the hopper of the DW series belt dryer are evenly spread on the mesh belt by the feeder. The mesh belt uses 12-60 mesh stainless steel wire mesh and is moved by the drive device inside the dryer. The drying section consists of several units, each with independent hot air circulation. Part of the exhaust gas is discharged by a dedicated moisture exhaust fan, and the exhaust volume of each unit is controlled by a regulating valve. In the upper circulation unit, air from the circulation fan enters the lower chamber through side ducts, flows upward through the heat exchanger for heating, and after distribution by the distributor, forms jet flow blowing toward the mesh belt, passing through the material layer and entering the upper chamber. The drying process involves hot air flow passing through the material layer to complete heat and mass transfer. The upper chamber is connected to the fan inlet via ducts. Most of the gas circulates, while a portion with lower temperature and higher moisture content is discharged as exhaust gas through moisture exhaust pipes, regulating valves, and moisture exhaust fans. In the lower circulation unit, air from the circulation fan first enters the upper chamber, then flows downward through the heat exchanger for heating, passes through the material layer into the lower chamber, which is connected to the fan inlet via side ducts and return pipes. Most gas circulates, and a portion is discharged. Upper and lower circulation units can be flexibly configured according to user needs, and the number of units can also be selected as required.
For dehydrating vegetables, the DW series belt dryer is generally used in series with three units, forming preliminary drying section, intermediate section, and final drying section. In the preliminary drying section, due to high material moisture content and poor permeability, smaller material thickness, faster running speed, and higher drying temperature are used. For materials with temperature not exceeding 60°C, the drying gas temperature in the preliminary section can be controlled below 120°C. The material residence time in the final section is 3-6 times that of the preliminary section, and the material thickness is 2-4 times that of the preliminary section. For materials requiring temperatures not exceeding 60°C, drying gas of about 80°C can be used. Multi-stage combination can better utilize the performance of the DW series belt dryer and achieve more uniform drying.

Typical Products
Products that can be dried using the DW series belt dryer: dehydrated vegetables, pellet feed, monosodium glutamate, chicken essence, coconut shreds, organic pigments, synthetic rubber, acrylic fiber, pharmaceuticals, medicinal materials, small wood products, plastic products, electronic component aging and curing, etc.

Main Technical Parameters

Process Flow Diagram