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Gentle Separation of Products by Vacuum Distillation
Vacuum distillation is a high value process for smooth separation. Homogenous mixtures of liquids with different boiling points can be separated by
distillation.
Distillation under vacuum conditions is used
- for heat sensitive products when distillation at atmospheric pressure causes thermal
decomposition
- for high boiling products when distillation at atmospheric pressure causes difficulties with
respect to energy losses and availability of construction material
In the fine vacuum range, a pressure reduction to 1/10 results in a decrease of the evaporation temperature by about 40o C.
An operating pressure far below 1 mbar reduces the evaporation temperature so far that decomposition of many biological or synthetic organic
compounds can be avoided.
In our distillation plants, pressures down to 0.001 mbar and temperatures up to 400o C can be achieved.
In a vacuum pot still unit, the pressure at the place of evaporation is remarkably higher than the suction pressure at the vacuum pump. This results
from pressure drop in the piping and from the static height of the liquid in the vessel.
Short path distillation or wiped path evaporation eliminate this disadvantage.
The vacuum required for the process defines the plant design:
Wiped Film Distillation with External Condenser or
Short Path Distillation with Internal Condenser
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