Gentle touch for distillation
8 Sep 2003
A new distillation process developed by German process firm GE Wiegand could bring major benefits to manufacturers of heat-sensitive materials.
Combining short-path distillation with falling-film evaporation, the technique can be used in the manufacture of vitamins, emulsifiers, fatty acids and aromatic substances.
The falling film short-path evaporator, developed by a team led by Daniel Bethge at GEA Wiegand's R&D centre in Karlsruhe, is designed to minimise the effective distance between its evaporation and condensation surfaces. This enables ultra-fine distillation vacuums, reducing the boiling point of the solutions in the system so that there is no decomposition or polymerisation of their components. Vacuum pressures as low as 0.001mbar can be achieved, the researchers claim, while residence times are also reduced.
The equipment is said to combine the advantages of short-path distillation, such as gentle product treatment and high fractionation efficiency, with those of falling-film evaporators, such as single-pass flow, an absence of rotating parts, a compact, multiple-tube design, and low investment costs.
