An Investigation for the Key Role of Surfactants in Activated Sludge Dewatering

摘要: In this research, compared with common chemical extractants, the efficacies of extracting extracellular polymeric substances (EPS) from activated sludge using cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) were studied. The results indicated that both CTAB SDS had good extraction ability, at dosage 0.2 g/g DS (dry solid), amounts extracted EPS 154.7 mg/g VSS 77.6 VSS, respectively. by its solubilization property, while synergistic effect replacement metal cation release intracellular materials. dewatering performances conditioned also investigated. Capillary suction time (CST), water content in cake bound used to evaluate behaviours. showed that, commercial cationic polyelectrolyte, CPAM, could significantly reduce water. However, did not help improving filtration performance whole range. For CTAB, only when was above 0.1 DS, rate increased due reaggregation dispersed flocs. dependent on detaching dissolving sludge, which resulted changes floc structure.