Abstract: A thin wiped-film evaporator comprises an upright cylindrical vessel with a vertical rotor shaft extending concentrically within the vessel. An inlet pipe supplies liquid to be evaporated to a distributor which spreads the liquid around the inner wall of the vessel, and a series of wiper assemblies carried by the rotor shaft below the distributor serve for the creation of a thin liquid film on the vessel's inner wall, heating means being provided to evaporate the liquid film. The evaporator includes a vapor inlet and a liquid discharge.To enable the evaporator to handle corrosive liquids or products, the internal surface of the vessel is corrosion resistant as are the other parts within the evaporator. In particular, the vessel's inner wall and the rotor shaft are glass (or enamel) lined and additionally at least part of each wiper assembly can be glassed: the other internal parts can be of fluorocarbon.

Abstract: A liquid heater or plate evaporator for partially evaporating liquid from a solution within the heater to increase its concentration, including evaporator and heater plates arranged in an alternating sequence in tandem and having heating or liquid channels between adjoining plates, the plates having registering apertures for heating medium, the solution to be evaporated, condensate therefrom and for a product mixture comprising concentrated solution and vapor each evaporator plate aperture having a distributor and guides to uniformly distribute the solution across the evaporator plate and to discharge it through discharge apertures located in a lower part on either side of the plate.