Distillation unit

Abstract

A distillation unit 2 comprises an evaporation chamber 12, a condenser 22, and a cooler 25 adapted to externally cool the condenser. An air heater 6 in the form of a solar chimney may be provided between an inlet 14 of the evaporation chamber and condenser. The heater may serve to heat air passing through it in order to increase convection currents within the distillation unit. In use the heated air passes to the evaporation chamber where water is evaporated from sea water contained preferably in a basin 44 before entering the condenser for example an externally sea water cooled copper pipe. Condensate formed on the inside of the copper pipe is collected preferably in a tank 60 and cooled air is returned to the heater. Preferably the distillation unit is used to desalinate water in order to render the water drinkable. A further invention characterised by a solar chimney is also disclosed.