Each layer of the heating plates in the vacuum disc dryer is equipped with inlet and outlet pipes for heat carriers. Generally, the upper layers are heated using low-pressure saturated steam, hot water, or hot oil in series, parallel, or both, to control the temperature of each layer. Meanwhile, the bottom two layers are filled with cooling water to reduce the product temperature, recover heat, and ensure quality. The heating plates are fixed at a certain spacing on the cylinder frame and placed horizontally. Each layer is equipped with a cross arm frame. The upper and lower layers of the vacuum disc dryer are fixed at a 45° staggered angle on the central spindle and driven by a worm gear reducer, a stepless transmission, and a motor, rotating slowly at 0.6~3.7 (r/min). Each arm frame is equipped with multiple detachable plow-shaped rake blades or flat scrapers, arranged equidistantly. The rake blades adopt a hinged and spring-loaded swing structure, allowing their bottom edges to float on the disc surface in response to the material. The angle of the rake blades can be adjusted according to the material properties to ensure that the material continuously moves forward on the disc surface.