Bound water in sewage sludges and its relationship to sludge surfaces and sludge viscosities

Abstract

Abstract An examination of activated and digested sludges has shown that surface components are significant in determining the rheological characteristics of these sludges. On the basis of a series of enzymic treatments, it would appear that in activated sludge the most important constituents are polysaccharide and protein; whilst in digested sludge, lipopolysaccharide and, at times, proteins are the most significant surface polymers. Subsidiary studies showed that the bound water content of the sludges was associated with the rheology and that this association could be modified by the action of metal ions.