Vertical tube foam evaporation for water desalination

Vertical tube foam evaporation (VTFE) provides a method of enhancing evaporator performance substantially by increasing the brine-side heat transfer coefficient. It reduces the temperature needed to drive evaporation and the energy required; consequently, the evaporation rate or evaporator capacity is increased under constant temperature conditions. VTFE applied to multiple effect evaporators, to evaporation with vapor compression to drive the process and to waste-heat evaporation of aqueous solutions are illustrated by test data obtained with pilot plants operated under realistic process conditions and utilizing full-size distillation tubes.