SZG Bi-conical Rotating Vacuum Dryer

The SZG Conical Vacuum Dryer is a heat-conduction type drying equipment developed successfully in the early 1980s, capable of intermittent operation under atmospheric and vacuum conditions. The conical rotary dryer is energy-efficient, reduces operating time, lessens labor intensity, minimizes losses, and prevents contamination, resulting in a higher purity product. The conical dryer now has a series of models, with common capacities including 500L, 1000L, and 1500L. Common materials include stainless steel, enamel, and electric heating. In recent years, this dryer has been widely used in industries such as chemicals and food processing.

The SZG Bi-conical Vacuum Dryer is our newly developed drying equipment, combining domestic similar product technology. The bi-conical vacuum uses a belt-chain two-elastic connection method, ensuring smooth operation. The specially designed process fully demonstrates the good concentricity of the two shafts, with the heat medium and vacuum system both utilizing reliable mechanical seals or US technology rotary joints. On this basis, we have developed the SZG-A model, which features both variable speed control and constant temperature control.
As a professional manufacturer of drying equipment, our products cover a full range from high-temperature thermal oil as the heat medium to medium-temperature steam and low-temperature hot water. For drying sticky materials, we will specially design a "scraping blade" mechanism or install ball bearings inside the tank for you.

This dryer rotates a jacketed, symmetrical cone-shaped vessel, continuously agitating and mixing the material with the help of an internal lifter or the cone's own inclination. Steam enters from one side of the hollow rotating shaft through a rotating joint and exits from the other side. The dryer is equipped with a filtered exhaust pipe, which releases gas from the center of the shaft at the opposite end.

This machine achieves high vacuum levels, with a simple internal structure, easy cleaning, and all materials can be fully discharged. Additionally, due to the container's rotating wall surface having no material accumulation, the heat transfer coefficient is higher. The filling rate for the feeding material should be between 30% to 50% of the dryer's area, but for materials with a significant change in volume before and after drying, the filling rate can reach 65%. Moreover, since the material also rotates within the drum dryer, dust inevitably enters the exhaust pipe, so the bend in the exhaust pipe and the structure leading to the outside should be easy to clean. For further drying without particle pulverization, a twin-conical drum dryer is more suitable.

Operating Principle ：
The conical dryer is categorized as a moving bed dryer in terms of material handling methods, and it is a type of energy-saving, intermittent operation machine. The dryer employs a conduction heating method in its structural design to remove liquids from the material, achieving a high drying rate at a lower temperature under vacuum conditions. The vacuum operation is conducted within a rotating container, enabling energy exchange through the conduction heat of the container jacket walls and the thermal motion of gas molecules formed by the vacuum inside, thus enhancing heat transfer efficiency. It promotes the diffusion and evaporation of water molecules within the sealed container, transforming them into steam and expelling it rapidly to achieve quick drying of the material.

Equipment Structure:

      The twin cone dryer consists of a double-layered vessel (body) with jacket, drive system, heating unit, vacuum suction device, and frame, etc. The body structure design employs a gravity mixing container with a double-cone fixed-axis rotation and no mechanical stirring, utilizing the gravity generated by material flow to form a natural frictional stratified flow between materials. It also combines the characteristics of vacuum operation in a sealed container.
  

Suitable Materials:
Concentrated, mixed, dried, and低温dried materials (such as biochemical products) in powdered, granular, and fibrous forms, suitable for chemical, food, and other industries. Particularly suited for drying materials that are prone to oxidation, volatility, heat sensitivity, strong irritation, toxicity, and those that require crystalline structure integrity.

Performance Features:
The conical rotary dryer is suitable for drying powdery and granular materials (not suitable for sticky, paste-like materials).
The moisture content of the raw material is around 15%. Generally, the wet powder can be directly added to the dryer after being dehydrated by a centrifuge. If there are lumps, they can be crushed with a powder mill before drying.
The dryer can be used to dry materials containing moisture, crystalline water, or solvents. Moreover, the solvents can be recycled, which is both economical and safe.
The dryer is particularly suitable for drying heat-sensitive materials. The jacket can be heated not only with steam but also with hot water, and can be cooled with cold water. The vacuum degree, temperature, and drying time can be adjusted according to process requirements.
This machine is suitable for materials that require strict specifications for crystal shape. Due to the stainless steel or glass-lined construction of the dryer, the inner wall is smooth, with a rotation speed of 4-6 r/min, and the material moves in a "diamond-shaped path." There is no impact between material crystals, ensuring the integrity of the spherical crystal shape.

The machine ensures uniform heating of the dry powder, resulting in materials with moisture content below 0.5% to 0.1%. The color grade remains the same before and after drying, with other quality indicators stable.

After the machine material is dried, the jacket should be cooled with cold water to reach room temperature before discharging. It can also be used to mix materials, replacing the mixer.

Technical Specifications:

Note: For materials with significant volume changes before and after drying, the filling coefficient can be appropriately increased or decreased.