The dryer has several modes such as belt drying, drum drying, box drying, tower drying, etc.; the heat source includes coal, electricity, gas, etc.; the material has hot air flow type and radiation type during the drying process. The hot air drum drying is the hot air flow moving forward from the tail, fully in contact with the material, and fully utilized by the heat conduction, convection, and radiation heat transfer; this article is about the working principle of the dryer, let's take a look. ?