Falling Film Evaporator

Due to the intimate contact of the liquid with the heating surface, these evaporators are sensitive to fouling from precipitating solids; liquor velocity, typically low at liquor inlet (see above) is usually not sufficient to perform an effective self-cleaning of the tubes. Falling film evaporators are therefore used in clean, non-precipitating liquids. A typical application, in chemical industry, is for concentration of caustic soda.