Conical Screw Vacuum Dryer

a photo of a man next to a Vrieco Nauta vacuum dryer

Product Description

The Vrieco-Nauta® conical screw vacuum dryer is a universal batch dryer suitable for drying powders, granules, pastes and viscous slurries, especially when products are heat sensitive, contain solvents and are toxic or explosive.

With over a thousand active units in the market Vrieco-Nauta® conical screw vacuum dryer technology has for over 50 years been considered a leader in the field of process technology.

It is capable of handling products that become heavy and sticky during drying and can be used for vacuum operations such as reaction/crystallisation, heating/cooling, sterilisation, liquid/solid separation and de-aeration and thermal processing including sterilisation.

The advantages of undertaking several processes in one vessel offer significant investment cost savings as well as savings on labour and space. The Vrieco-Nauta® conical screw vacuum dryer also offers:

  • Efficient drying of loose powders to heavy pastes and viscous liquids
  • Batch volumes ranging from 5 to 22 000 litres
  • No segregation and no product degradation
  • Full compliance with international standards (FDA, cGMP, EHEDG)
  • Automated cleaning solutions with our patented CIP filter and CIP skids
  • Sterile processing (SIP)
  • Interchangeable screw agitator for dryers larger than 20 000 litres

The thermal energy needed for drying is introduced into the product through a steam/oil/water heated jacket which with efficient mixing distributes the heat through the product.

The vacuum inside the dryer allows vapour to be removed at low temperatures. The vapours are removed through a dust filter fitted on top of the vessel. A condenser fitted to the dryer is used to recover solvents.

Moisture content of the product can be controlled by monitoring the weight of condensate or using the Hosokawa sampler for taking samples from the product inside the dryer under vacuum. The Vrieco-Nauta® Conical Screw Vacuum Dryer offers excellent secondary drying up to ppm level.

Vrieco-Nauta® dryers are available in the following standard sizes however Hosokawa Micron Ltd also offers a bespoke design option.

Hosokawa tables_CONICAL DRYER* Jacket surface temperature T=50°C


Materials of construction:

All grades of stainless steel, Monel, nickel, titanium, Hastelloy, etc.


  • Vacuum filter
  • Sampler
  • Heating/cooling skid
  • Ball segment valve
  • Lump breaker
  • Liquid injection
  • CIP/SIP skid

Please contact for more details:

+44 (0) 1928 755100