Multi-effect rotary distillation process

Abstract

A thermally driven multi-effect distillation process and apparatus are disclosed in which liquid is introduced into a plurality of evaporating and condensing stages or chambers while heat energy is passed through the stages or chambers in a direction countercurrent to the direction of flow of the liquid which undergoes evaporation to form condensate and distilland in each stage or chamber while transferring the heat of condensation to the next downstream stage or chamber and maintaining a minimum temperature differential between stages or chambers, and separately removing condensate and distilland from each stage or chamber while rotating the stages or chambers about an axis passing through the points of introduction thereto of the liquid and heat energy. Generally the apparatus comprises a plurality of adjacent evaporation and condensation chambers and means for introducing liquid and heat energy thereto in countercurrent directions. The walls of the chambers, formed of spaced heat conductive sheets, act as heat transfer means. Common walls of adjoining chambers provide condensing and evaporating surfaces on the opposite sides. The chambers are provided with means for separate removal of condensate and distilland and means for rotating them about an axis passing through the points of introduction of liquid and heat energy thereto.