GB672919A - High-vacuum unobstructed path fractionating distillation method and apparatus - Google Patents

Abstract

<PICT:0672919/III/1> <PICT:0672919/III/2> A high-vacuum unobstructed path fractional distillation apparatus comprises a gas-tight evacuated column 12 having means, e.g. an electric coil 44, for heating its sides, a heated rotatable member at the lower end of the column with an upper vaporizing surface 20, means for feeding distilland on to the surface 20, a rotatable shaft 36 in the upper part of the column carrying a brush, the outer ends of the bristles 34 of which touch the wall of the column, and a condensing surface at or adjacent the upper end of the column. In the apparatus of Fig. 1, distilland is fed on to the centre of rotatable surface 20, which is heated by electric element 24, by a conduit 26. Residue is taken off at 30. The condensing surface is a part of the wall of the column cooled by a coil 48 or air blast. Condensate collects in gutter 50. The shaft 36 is cooled by fluid forced through conduit 54. Vapours condensed on the shaft 36 are flung to the walls of the column by the bristles 34 and there revaporized, a portion of the vapours again condensing on the shaft 36. The alternate condensation and vaporization with cross-current contact with vapours rising from surface 20 causes a tendency for the heavier components to pass downwards and the lighter components upwards. In Fig. 2 distilland is fed to the centre of the column by line 26. Feed not vaporized on the walls of the column collects in gutter 64 and is fed by conduit 66 to vaporizing surface 20. Residue from surface 20 is taken off by gutter 28 and may be recycled to feed line 26 by pump 70. The condenser 56 is separate from the column. The shaft 36 carrying the bristles 34 is cooled by air or water forced through conduit 54.