GB1307375A - Process and apparatus for the rectifying fractionation of liquid mixtures under low pressure - Google Patents

Abstract

1307375 Fractional distillation HECKMANNWERK KG 7 Oct 1970 47575/70 Heading BIB Liquid mixture to be fractionated is pumped from the sump 13 of container 1 to falling-film evaporator 8, and the mixture of vapour and non-vaporized liquid flows back into container 1; the vapours rise in the container and are cooled and partially condensed by three bundles of vertical tubes 2, 3, 4, and means are provided whereby condensates from condensers 5, 6, 7 respectively, flow in film-form down the inside surface of the tubes 2, 3, 4. The system is maintained under vacuum, e.g. 10<SP>-3</SP> Torr) by conduits (not shown) connected to container 1 and condenser 7; and the pressure in the tubes is lower than in container 1. The vapours rising in container 1 are partially condensed on the outside surfaces of the tubes 2, 3, 4; and films of condensate flow down the tubes while undergoing exchange of material with the rising vapours. The rectified vapours flow through conduit 14 to condenser 5; and the condensate is distributed on the internal surface of tubes 2. The more volatile components of the downflowing films of condensate in tubes 2 are vaporized, and the vapour flows to condenser 6. The non-vaporized condensate, reaching the lower ends of tubes 2, passes through perforations in manifold 12 into sump 13. The condensate from condenser 6 is partially revaporized in tubes 3, and the vapours are condsensed in condenser 7. The condensate from condenser 7 is partially revaporized in tubes 4, and the vapour flows out of conduit 15 to the product condenser. After the volatile components have been distilled off by fractions, the remaining liquid residue is removed through outlet 17.