The double cone rotary vacuum dryer is suitable for vacuum drying and mixing of powder and granular materials in industries such as medicine, food, and chemical industry, especially for materials with the following requirements: cannot accept high-temperature thermosensitive materials; Materials that are prone to oxidation and hazardous; Materials that require the recovery of solvents and toxic gases; Require materials with extremely low residual volatile content; Materials with requirements for crystalline shape; Require sufficient and uniform mixing of materials.


The double cone rotary vacuum dryer uses a vacuum system to continuously heat the dried material while vacuuming it, allowing the moisture inside the material to diffuse to the surface through pressure or concentration differences. Water molecules (or other non condensable gases) gain sufficient kinetic energy on the surface of the material, overcome the mutual attraction between molecules, and diffuse to the low-pressure space of the vacuum chamber, which is then pumped away by a vacuum pump to complete the separation from the solid. Due to the small temperature gradient between the inside and outside of the material during vacuum drying, the moisture can move and collect independently due to reverse osmosis, effectively overcoming the phenomenon of dispersion caused by hot air drying. The heat transfer coefficient U of the double cone rotary vacuum dryer jacket is independent of the operating pressure, and for non bonded materials U=116-140W/(m? · K) and adhesive materials U=80-93W/(m? · K). The heat transfer area is calculated based on the area of the material in contact with the cylinder wall. The cylinder of the double cone rotary vacuum dryer is designed as a pressure vessel, with the inner cylinder subjected to external pressure and the outer cylinder subjected to internal pressure.


The double cone rotary vacuum dryer is pumped out through a vacuum pump through a vacuum exhaust pipe. Due to the vacuum state inside the tank, and the rotation of the tank causing the material to constantly flip up, down, inside and outside, the drying speed of the material is accelerated, the drying efficiency is improved, and the goal of uniform drying is achieved. The double cone rotary vacuum dryer system mainly consists of a double cone rotary vacuum dryer, condenser, dust collector, vacuum pumping system, heating system, cooling system, electrical control system, etc. The process of vacuum drying is to place the dried material inside a sealed cylinder, use a vacuum system to vacuum and continuously heat the dried material, so that the moisture inside the material diffuses to the surface through pressure or concentration differences. Water molecules (or other non condensable gases) gain sufficient kinetic energy on the surface of the material, and after overcoming the mutual attraction between molecules, diffuse to the low-pressure space of the vacuum chamber, Separated from the solid by being evacuated by a vacuum pump.


Technical requirements for double cone rotary vacuum dryer


(1) Working mode: Under vacuum, the tank is heated by introducing thermal oil or hot water into the jacket, and the heat comes into contact with wet materials through the inner wall of the tank. The water vapor or other gases that evaporate after absorbing heat from wet materials are extracted through a vacuum pump through a vacuum exhaust pipe.


(2) The design pressure inside the tank is -0.1~0.5MPa, and the jacket thermal oil is heated. The jacket design pressure is ≤ 0.3MPa;


(3) The drying room has a volume of 200L, with enamel lining and a resistance to 130 degrees. The temperature of the inner layer and the interlayer are displayed;


(4) Equipped with solvent recovery device, variable frequency speed regulation, and explosion-proof motor;


(5) Material requirements: Inner liner: enamel, jacket and framework: Q235A, outer wall: SUS304 stainless steel.