The working principle of the rotary drum dryer is that under the action of dry air, the material rolls in the rotating drum to achieve the drying effect.

Rotary drum dryer is an inclined horizontal rotary cylinder, with a supporting device, a transmission device, a cylinder and a sealing structure such as inlet and outlet device.

The position of the drum is slightly tilted horizontally to allow gravity to help the material pass through the drum dryer. As the drum rotates, the lifting device picks up the material and drops it through the air stream to maximize heat transfer efficiency. When handling clumps, the  rotation effect of the dryer can also further round and polish the granules.