Process Description - Wiped Film (Short Path)
Feed liquid is admitted into still under vacuum, immediately spread into a very thin film and forced quickly down the evaporation surface. Heated walls (orange) and high vacuum (yellow) drive the more volatile components (distillate) to the closely positioned internal condenser as the less volatile components (residue) continue down the cylinder. The resulting fractions, thus separated, exit through individual discharge outlets. Depending on application, the desired product is either the distillate or the residue fraction. Condensable low MW compounds collect in cold trap upstream of vacuum system. For high solvent loads, an optional external condenser may be installed immediately downstream of the still. (With external condenser incorporated, the internal condenser may be removed to provide a typical "WFE" or Wiped-Film Evaporator configuration.)
Pope Scientific's Solution Driven Dimension
Pope adds superior design and construction to the basic wiped-film/short path still process. This has enabled Pope stills to sustain pressures down to one micron for either molecular distillation or solvent stripping. Pope variable speed control of the wipers coupled with the ability to reverse rotation, allows an extremely wide variation of hold-up time for the process fluids in the evaporator body.
Molecular Distillations Of Esters, Fatty Acids, Mono, Di, & Triglycerides
Residue Removal / Decolorization
Vitamin, Nutraceutical, Essential Oil Isolation
Wax Fractionation
Oil Deodorization
PCB, Insecticide Removal
Water Removal - ppm Level
Food, Flavor Purification
Solvent Recovery
Many Other Specialties
Wiped-Film Molecular (Short-Path) Still. To be used where the distillate is of high boiling point. High vacuum (to 0.001 torr) and a close proximity internal condenser are utilized.
Wiped-Film Evaporator (WFE). This design is selected where there is a significant percentage of moderate or low boiling distillate. Medium vacuum (to 0.1 torr) and a high surface area external condenser are utilized.
