Waste Water Reuse by Freeze Concentration with a Falling Film Reactor

Abstract

Experiments with a falling film reactor were conducted to examine the potential of the freeze concentration to reuse municipal waste water. The waste water was recycled in the falling film reactor while ice films were frozen on the cooled inner walls. Pure water was removed from the solution by crystallization, and the liquor was concentrated. Finally, the separated clear ice was melted. Various parameters such as conduction, TOC, COD and NH4-N of the melted ice and waste water concentrate were measured. A clearance efficiency up to 99% was observed for municipal waste water and 91% for high concentrated waste water. In addition, particulate solutions were removed from the aqueous phase as efficiently as the organic and inorganic solutes.