1.The steam heat transfer medium can be used for both half chemical process and full drying process, with simple system and few auxiliary equipment. 2.The exhaust gas treatment system is more smooth with less load. 3. High reliability, good continuous operation, day and night operation, suitable for drying materials with long time and large capacity. 4. The steam does not contact with the material, the amount of insoluble gas in the tail gas is less, it can be burned in the furnace, and the secondary pollution is less. 5.During operation, the oxygen content, temperature and dust concentration are low, and the system is safe. 6. The dryer conducts heat transfer through the shell wall, hollow shaft and the left and right sides of each vertical disc, with large heat transfer area, compact structure and small size. 7. The materials inside the dryer are wet materials. In order to prevent the materials from sticking to the turntable, there is a fixed long scraper on the inner wall of the shell, which extends to the gap between the discs to stir the materials and clean the disc surface. After crushing and stirring, the material becomes uniform particles, which is conducive to further disposal. 8. Low temperature heat source (≤180℃) is used for heating, so the materials on the disc will not overheat when stopping, and the restart will not be affected. 9. The material processing load is large, even if the feed is uneven, it can ensure the smooth operation, the internal operation resistance is small, and the energy consumption of the equipment is low.