Bound Water Content of Activated Sludge and Its Relationship to Solids Retention Time, Floc Structure, and Surface Properties

The bound water (BW) content of sludge from four bench‐scale sequencing batch reactors (SBRs), fed a glucose‐based synthetic wastewater and operated at different solids retention times (SRTs), and from five full‐scale, activated‐sludge systems treating different wastewater was determined using the dilatometric technique. Storing sludge at 4 °C before analysis resulted in a lower measured BW value. The SRT and surface charge were not correlated …