Recirculated Falling Film Evaporators

Recirculated falling film evaporators are used where insufficient feed liquor is available to utilize the heat transfer surface with single pass operation. 

Process
A portion of the product liquor is combined with the feed stream and is pumped to the upper liquor chamber.  Product retention time is greater than for the single pass F.F. evaporator but is relatively short as the operating volume is small.

Applications
Typical applications include many moderately heat sensitive food, pharmaceutical and chemical applications.