GB667285A - Improvements in or relating to apparatus for molecular distillation - Google Patents

Abstract

<PICT:0667285/III/1> <PICT:0667285/III/2> In a molecular distillation apparatus, distilland 20 in the base of a highly evacuated chamber 10 is picked up as a film on a number of rotating discs 19 dipping into the distilland and carried close to condensing surfaces 21 cooled by circulating brine refrigerant and disposed adjacent the upper parts of the discs. Condensate is collected in gutters 24 connected to a manifold 25 leading through a cooler 27 to a separator 26. Two receivers 33, 34 are connected to the separator, either being lowered to receive the distillate as required. The distilland is heated by an external heater 28 and the distillation controlled by means of vacuum gauge 32 and thermometer 29. Distilland is fed to the chamber 10 at 13 and the chamber may be emptied at 30. Successive fractions from a single batch of distilland may be collected. In a modification, Fig. 3 (not shown), heating is effected by passing fluid heated in an external chamber through a hollow shaft 39, Fig. 4, inside the shaft 15 carrying the discs 19. The fluid emerges into the shaft 15 at one end and passes successively through the discs 19 which are hollow and have internal baffles 41. Scoops 57 may be provided on the discs. The temperature drops successively from disc to disc as the heating fluid cools and separate fractions are collected simultaneously from the condensing surfaces. The distilland is passed continuously through the chamber 10 from an evacuated reservoir to an evacuated sump. Alternatively the discs may be heated uniformly, the apparatus then effecting a simple distillation. The discs 19 may be heated electrically instead of by circulating fluid.