Vacuum Rotary / Paddle Dryers

VRD Model Sizes

60% Wet Charge Working Capacity

Total Internal Capacity

2x4 VRD

   7.3 cubic feet

  10.6 cubic feet

2x8 VRD

  14.5 cubic feet

  21.2 cubic feet

3x10 VRD

  39.3 cubic feet

  63.0 cubic feet

3x20 VRD

  78.6 cubic feet

130.0 cubic feet

4x15 VRD

100.6 cubic feet

139.6 cubic feet

4x20 VRD

134.0 cubic feet

187.0 cubic feet


147.7 cubic feet

183.7 cubic feet

5x30 VRD

295.4 cubic feet

369.5 cubic feet

6x36 VRD

536.2 cubic feet

584.4 cubic feet

Vacuum Rotary / Paddle Dryers provide fast, uniform, low temperature drying of press cake, filter cake, and slurry type materials requiring agitation and recovery of solvents during drying.  The batch drying time depends on the composition, nature and amount of solvent present in the wet product.

Consisting of a stationary horizontal jacketed cylinder (vacuum chamber) designed for vacuum or pressure operation under controlled heat with an internal revolving agitator, which can be heated to further shorten drying time. The custom-select agitator mixes and circulates the product into contact with the heated surfaces to achieve uniform drying with minimum power consumption, tumbling, and dusting.

The batch operation of the vacuum rotary dryer is simplified by automatically loading (charging) the wet product into the top of the jacket cylinder with the agitator rotating for uniform distribution and complete dry product discharge through a pneumatically operated underside discharge door.

The jacketed cylinder and agitator are designed to meet the operating pressures and material compatibility requirements for each individual application and are built to comply with ASME, PED Pressure Codes or other national design and construction codes.

Due to hundreds of various types of products and demands of inducing and controlling a vacuum environment, almost all aspects of a vacuum rotary dryer’s mechanical design, operating components and ancillary support equipment can be customized to meet each individual’s process design application needs.

The vast majority of Buflovak vacuum rotary dryers are installed on a production-guaranteed basis because the specific process (chemistry) design was tested and then pilot-run in the Buflovak laboratory, which provided reliable scale-up data for correct dryer configuration and working capacity to meet each individual process design application.

The following chart is an example of the flexible vacuum rotary dryer capacity range to meet your specific dry product production rate. The length of any given rotary dryer diameter can be adjusted for exact volume requirements to meet and balance upstream and downstream design capacity.