Practical Application of Foam Fractionation Treatment of Low Quality Water

Abstract

The foaming technique has found extensive use for organic, ion, and colloid separations from liquid systems. When used to remove an ion or a colloid, a specific surface-active agent of opposite charge to the particle being removed is added to the solution and floated to the surface of the suspension by gas bubbles. The ion or colloid is adsorbed at the bubble interfaces and collected within the froth formed at the surface of the container. The froth, with the contaminant or concentrated material (depending upon the process and its use) is physically separated at this point and further processed or discharged to waste. The clarified bottom liquid is therefore suitable for other uses. In the water supply field, the bottom liquid is the important product that is to be recovered and used for consumptive purposes. Much research has been performed on the theory and applications of various adsorptive bubble separation methods. These studies are well documented in the literature for various industries and applications which might take advantage of the method. It was not the intent of this work to amplify the findings of other research. The project was undertaken in an attempt to scale-up laboratory experiments previously performed at this Institute. No extension of theory, new processes, or revolutionary findings were attempted.