To handle pastes, creams, grains, powers and fibers, we have developed the rake vacuum driers by improving and strengthening domestic rake vacuum driers. Stable and durable cylindrical gear reducer functions as transmission parts and driving shafts are solid shafts made of thickened stainless steels and rake teeth are high strength cast teeth made of stainless steels, thus stable operation in severe working environments is ensured. Two or four impact rods may be equipped in the housing so as to rapidly dry and mill the materials. Heating medium can be steam, heat transfer oil and hot water.
The driers have wide application range and high drying rates. They are applicable for almost all materials of different properties and states, especially explosive and oxidizable materials due to jacket heating and high vacuum exhaustion.
The rake teeth continuously stir the material to opposite directions during drying, so the drying quality is high, the materials are uniformly mixed and steam consumption is small. The driers are easy to operate. Volatile gases can be recycled to reduce environmental pollution.
The driers are especially applicable for thermo-sensitive materials, materials which are easily oxidized at high temperature or easily hardened during drying, and materials which release steam during drying that shall be recycled. Since materials are dried into powders, the driers are suitable for materials of powder products. Such products can be directly packed after drying. Water contents of the materials supplied to the rake vacuum driers can be 90%, and the materials can be pastes, creams, grains, powders or fibers. The drying can reduce the water contents to 1%, even 0.5%. The driers are being widely used in production of solid sodium (potassium) alkoxide.