The product enters above the heating zone and is evenly distributed on the inner surface of the device through the rotor, and the hinged blade element transfers the viscous material along the hot surface and facilitates the heat transfer.
The volatile components evaporate rapidly and flow countercurrent through the solid/liquid flow unit, and the vapor can be condensed or subsequently processed on existing dryers.
As the volatiles evaporate, the solid eventually stops flowing and produces the material ejected from the wall by the film dryer blade, and the free-flowing solid then falls from the rest of the evaporator to the discharge part; For horizontal dryers, segmented blades are used to push solids towards the discharge section.
The non-volatile components are discharged to the bottom of the film dryer through a specially designed discharge section. Dryers usually use special rotating or spherical disc valves for solid discharge treatment. Depending on process requirements, solids can also be discharged directly into the hopper or container.
The dryer is heated indirectly by steam or hot oil and can be operated in half batches or continuously.
Its relatively short residence time and open low pressure drop configuration allow the continuous and reliable handling of many heat-sensitive viscous materials without degrading the product.
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