FALLING FILM EVAPORATOR
These evaporators can be used for demonstration/training and small capacity commercial applications. The system has proved useful in concentrating a wide range of food products including fruit juices, plant extracts and glucose solution.
The falling film version of the long tube evaporator eliminates the problems associated with hydrostatic head. Liquid is fed at the top of long tubes and allowed to fall down the walls as a film. Evaporation occurs on the surface of the highly turbulent film and not on the tube surface. This requires that temperature differences be relatively low.
With suitable preheating arrangement the evaporator can function as once through system, giving high quality concentrates. These can be used for heat sensitive fruit juices and plant extracts.
Falling film evaporators can also be designed as multiple effect evaporators employing falling film system at the final effect.