GB392851A - A plant or still for distilling water or other liquids - Google Patents

Abstract

<PICT:0392851/III/1> In distilling liquids, e.g. water, the vapours produced are cooled in three or more stages in the first of which the preheated liquid to be distilled is further heated in the intermediate stage the vapour is condensed by a separately circulated cooling liquid, while in the last stage the condensate is finally cooled by preheating the cold liquid. The intermediary stages may be used to preheat feed water and convert it into steam. All the stages may be assembled in a single unit, e.g. a still comprising an evaporator 1, a first stage cooler 2, an intermediary cooler 3, and a final cooler 4. Water supplied from a tank 17 is fed through a pipe 5 into the cooler 4 where it is heated by condensate flowing through the coil 9b. It then passes through a pipe 6 into the unit 2 where it is further heated by the hot vapours flowing through a coil 8a and finally flows into the evaporator 1 where it is vaporized by a steam-heated coil 40. The vapours pass off through a pipe 8 and after traversing the coil 8a pass through a coil 9 where they are condensed by water supplied from a tank 16 through a pipe 11 to the cooler 3, the heated water passing out through a pipe 12 being recycled through an air cooler 13 by a pump 14. Warm water for domestic &c. purposes can be drawn off through the pipe 15. Temperature control is afforded by a thermostat 21 operating a switch 23 controlling the supply of heating fluid or a switch 24 controlling the cooling fluid. A modified apparatus is described for operation at super-atmospheric pressure.