Fenton试剂与CPAM联合调理对污泥脱水效果的影响研究

Sludge Dewaterability with Combined Conditioning Using Fenton's Reagent and CPAM

含水率是影响污泥处置效果与成本的重要因素,通过泥饼含水率、上清液COD、蛋白质、多糖质量浓度、污泥粒径等指标,研究了阳离子聚丙烯酰胺(CPAM)和Fenton试剂单独及联合调理对污泥脱水效果的影响,初步探讨其调理机制.结果表明,CPAM阳离子度越高,脱水效果越好,且酸性条件有利于改善CPAM的污泥脱水效果.Fenton试剂H2O2投加量越高,污泥脱水效果越好.Fenton试剂与CPAM联合调理时污泥脱水效果更为显著,投加FeSO4=2 g.L-1、H2O2=6 g.L-1,污泥含水率由原泥的85.5%降低至76.7%,再投加CPAM 3 kg.t-1联合调理后污泥含水率降至74.8%.Fenton试剂对胞外聚合物的破解作用使污泥粒径变小,比表面积增大,释放部分的吸附水和内部水;CPAM与Fenton试剂的联合调理,将分散的污泥絮体凝聚,污泥平均粒径由35.16μm增至50.50μm,比表面积由未加入CPAM的0.39 m2.g-1降至0.20 m2.g-1,联合调理对污泥脱水效果的改善作用优于单一絮凝剂调理.

The moisture of sludge significantly influenced its dewaterability and the disposal cost.Cationic polyacrylamide（CPAM） and Fenton＇s reagent were investigated for sludge dewatering with separate and combined conditioning.Several parameters were used to evaluate the dewatering performance and to analyze the conditioning mechanism,such as cake moisture,soluble COD,protein and polysaccharide contents in supernatant and sludge particle size.The results indicated that favorable dewaterability was achieved when the sludge was conditioned at higher CPAM degrees,and sludge dewatering ability was further improved at acidic conditions.In Fenton reaction,higher H2O2 dosages enhanced the dewatering performance of sludge.Combined conditioning using Fenton＇s reagent and CPAM led to considerable improved sludge dewaterability.At the optimized dosages of FeSO4（2 g.L-1） and H2O2（6 g.L-1）,the sludge moisture declined to 76.7% from 85.5%（raw sludge）,while a moisture as low as 74.8% was obtained by combined conditioning using CPAM（3 kg.t-1）.Sludge particle size went down and the specific surface area grew bigger after Fenton reaction.As a result of disintegration of extracellular polymeric substances（EPS）,the adsorbed and intrinsic water were released from microorganisms and sludge flocs.CPAM addition remarkably promoted the coagulating and flocculating of dispersed flocs.Sludge particle size changed from 35.16 μm to 50.50 μm,and the specific surface area declined from 0.39 m2.g-1 to 0.20 m2.g-1.The combined conditioning using Fenton＇s reagent and CPAM was proved to be more effective in improving sludge dewaterability,compared with the separate conditioning.