Rotary drum dryer can be divided into different kinds when drying materials based on the different heat transfer ways, what are the specific classifications?
The indirect heat transfer type: this type is suitable for drying the powdery material which is cannot be polluted by coal ash or easy to dust, but the heat transfer efficiency is not very good.
The direct heat transfer type: The high-temperature gas is direct contact with material within the cylinder, directly transfer the heat to material. This type is suitable for drying the material which is not sensitive to high temperature flue gas or not afraid of coal dust pollution.
Compound heat transfer type: Firstly, the hot gas through the inner sleeve and make the heat indirectly transfer to material, then, from the inner sleeve to the outer sleeve to in direct contact with material and transfer heat, this type is more suitable for drying bituminous coal, and can avoid fire, explosion, loss of volatile.
Different transfer heat types have different drying effects on different materials, so customer should choose the best suitable equipment based on the character of the material.