Predicting bioflocculation: New developments in the application of flocculation theory

Abstract

Using flocculation theory, the importance of the solid‐liquid interfacial tension has been shown to be an important variable in determining the flocculation behaviour of activated sludge solids. To verify this correlation experimentally, a method has been developed for measuring the interfacial surface tension (contact angle). Measurements of contact angles and flocculation performance have been made for activated sludges produced under a range of operating conditions. The theoretically predicted correlation between flocculation performance and contact angle was confirmed experimentally.