title: Enhancement of waste activated sludge dewaterability by electro-chemical pretreatment.
abstract: The potential effects of electro-chemical conditioning on sludge dewatering treatments and its mechanism were investigated in this study. Capillary suction time (CST) and specific resistance to filtration (SRF) were used to evaluate sludge dewaterability. Extracellular polymeric substance (EPS) content and sludge disintegration degree (DD(SCOD)) were also determined in an attempt to explain the observed changes in sludge dewaterability. The results indicated that application of considered low electrolysis voltages (<20 V) enhanced sludge dewaterability, while it exceeded 30 V, the dewaterability of sludge was significantly deteriorated. Also, electrolysis pretreatment slightly enhanced sludge dewaterability with short electrolysis time (<20 min), while it significantly deteriorated sludge dewaterability with long electrolysis time (>30 min). The optimal electrolysis voltage and electrolysis time to give preferable dewaterability characteristics were found to be 15-20 V, and 15-20 min, respectively, which generated sludge with optimal EPS content (15-20mg/L) and DD(SCOD) (1.3-2.0%).
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240,China.
authors.forename: Hai-ping
authors.initials: HP
authors.lastname: Yuan
authors.forename: Xiao-fei
authors.initials: XF
authors.lastname: Yan
authors.forename: Cai-feng
authors.initials: CF
authors.lastname: Yang
authors.forename: Nan-wen
authors.initials: NW
authors.lastname: Zhu
mesh_terms: D004563:Electrochemistry; D012722:Sewage; D014867:Water
chemical_list: D012722:Sewage; D014867:Water