The structural feature of the paddle dryer is that a jacket is set on the cylinder body, and many hollow wedge-shaped blades are installed on the hollow shaft. During the drying operation, a heat carrier is introduced into the jacket, hollow shaft and paddle to supply all the heat required for drying; a very small amount of hot air is introduced into the dryer to serve as a carrier for the water vapor evaporated during drying .
The paddle dryer is a horizontal stirring type continuous drying equipment mainly based on heat conduction. The heating medium is not in direct contact with the material.
In addition, although there are many stirring blades in the dryer, the materials are mixed evenly, but the flow of materials in the dryer from the feeding port to the discharging port is basically a plug flow flow, the residence time distribution is narrow, and the product is evenly dried.
The material has wide adaptability and the product is evenly dried. The paddle dryer can adjust the material retention in the dryer according to the material properties and drying conditions. The residence time of the material can be increased to meet the drying requirements of difficult-to-dry materials and high-moisture materials.
It can also adjust the feeding speed, the rotation speed of the shaft and the temperature of the heat carrier, and the residence time of the material can be arbitrarily selected between a few minutes and a few hours. Therefore, it is suitable for both easy-drying and difficult-drying materials.
The material enters the machine from the feeding port, and is stirred and conveyed by the hollow blade to the discharge port for discharge. During the conveying process, the material is heated by the hollow blade and the jacket at the same time, evaporated and dried. The stirring also plays the role of uniform contact between the material and the wall surface and the paddle, which accelerates the heat transfer. High thermal efficiency is the outstanding advantage of this machine, which is also determined by the structural characteristics of this machine. Because the hollow blade is wedge-shaped, the material on the heat transfer surface moves violently, which greatly improves the heat transfer efficiency.
In addition, due to the reverse rotation of the two-shaft blades, the materials on the inclined surface are alternately compressed and expanded in sections, so that the materials near the heat transfer surface are vigorously stirred, which improves the heat transfer effect.
