Vacuum Drying
Vacuum Shelf Dryers are specified for products requiring uniform, low-temperature drying with no agitation or compression.
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Delicate, heat-sensitive materials are dried safely at extremely low drying temperatures. Operating under vacuum, the product is protected from oxidation and atmospheric contamination and released solvents are fully recovered.
Consisting of a square or round vacuum chamber with customized fixed internal shelves; the wet material to be dried is loaded into pans or trays and manually placed on the shelves. The top part of each shelf is flat with a coil jacket on the underside to circulate steam or liquid heating medium for the desired operating temperature.
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Shelf drying is a common unit operation for reducing the liquid solvent content of solid cakes prior to material storage or downstream processing. Where the use of high temperatures could result in product stability issues, shelf dryers may employ vacuum to evaporate volatiles at low temperatures. Chemical synthesis of highly engineered compounds often requires efficient drying at less than ambient temperatures. The combination of shelf drying and sub-atmospheric pressure allows for efficient volatile material evaporation while maintaining the solid cake at relatively low temperatures.
VTD-1 | VTD-2 | VTD-3 | VTD-4 | VTD-5 | VTD-7 | |
---|---|---|---|---|---|---|
Manufacturer | Buflovak | Buflovak | Devine | Devine | Stokes Pennwalt | Devine |
Material of construction | Carbon steel | Carbon steel | Stainless steel | Stainless steel | Stainless steel | Stainless steel |
Total area | 156 square ft | 156 square ft | 110 square ft | 110 square ft | 60 square ft | 132 square ft |
Shelf area | 12 square ft | 12 square ft | 11 square ft | 11 square ft | 6 square ft | 11 square ft |
No. of shelves | 13 | 13 | 10 | 10 | 10 | 12 |
Vacuum | Up to 26 inches | Up to 26 inches | Up to 26 inches | Up to 26 inches | Up to 26 inches | Up to 26 inches |
Nitrogen sweep | Up to 100 scfh | none | none | Up to 150 scfh | none | Up to 150 scfh |
Heating | Closed loop water | Closed loop water | Closed loop water | Closed loop water | Closed loop water | Closed loop water |
Temperature range | 25-90 deg C | 25-90 deg C | 25-90 deg C | 25-90 deg C | 25-90 deg C | 25-90 deg C |