两性壳聚糖复合絮凝剂对印染废水的絮凝性能研究_范大和

[基金项目]国家自然科学基金资助项目(30471362);江苏省环保基金资助项目(2002031)第28卷第9期2008年9月工业水处理IndustrialWaterTreatmentVol.28No.9Sep.,2008StudyontheflocculatingpropertiesofcompositeflocculantofamphotericchitosanderivativefortreatingprintinganddyeingwastewaterFanDahe1,CaiZhaosheng1,2(1.DepartmentofChemicalandBiologicalEngineering,YanchengInstituteofTechnology,Yancheng224003,China;2.InstituteofChemicalIndustryofForestryProducts,CAF,Nanjing210042,China)两性壳聚糖复合絮凝剂对印染废水的絮凝性能研究范大和1,蔡照胜1,2(1.盐城工学院化学与生物工程学院,江苏盐城224003;2.中国林业科学研究院林产化学工业研究所,江苏南京210042)[摘要]以两性壳聚糖为絮凝剂处理了丝绸印染废水,并与羧甲基壳聚糖、壳聚糖季铵盐、聚合氯化铝和聚丙烯酰胺的絮凝性能进行了比较,研究了废水的pH、絮凝剂的质量浓度、助凝剂的类型及其与两性壳聚糖的复配比对其絮凝性能的影响。结果表明,两性壳聚糖的絮凝性能优于羧甲基壳聚糖、壳聚糖季铵盐、聚合氯化铝和聚丙烯酰胺;在pH为5.0~6.0、絮凝剂两性壳聚糖的质量浓度为90mg/L时,废水的COD去除率可达76.8%;助凝剂的加入可提高两性壳聚糖对COD的去除率,在m(助凝剂)∶m(絮凝剂)=40、混凝剂的加入量为2500~3000mg/L时,废水COD的去除率可在80%以上。[关键词]两性壳聚糖;化学需氧量;絮凝剂;助凝剂;絮凝性能[中图分类号]TQ314.253;TD926.5[文献标识码]B[文章编号]1005-829X(2008)09-0047-04Abstract:Thesilkprintinganddyeingwastewaterhasbeentreatedwithamphotericchitosanasflocculant.Theflocculatingpropertyofamphotericchitosanhasbeencomparedwiththatofcarboxymethylchitosan,quaternizedchitosan,poly(aluminumchloride)andpolyacrylamide,respectively.TheeffectsofthewastewaterpH,massconcentrationoftheflocculant,typeofassistantflocculantandmassratioofassistantflocculanttoamphotericchitosanontheflocculatingpropertieshavebeenstudied.Theresultsindicatethattheflocculatingpropertyofamphotericchitosanisbetterthanthatofcarboxymethylchitosan,quaternizedchitosan,poly(aluminumchloride)andpolyacrylamide.WhenitspHis5.0-6.0andmassconcentrationofamphotericchitosanis90mg/L,theCODremovalrateofwastewatercouldbeupto76.8%.AddingtheassistantflocculantcouldhelpamphotericchitosantoimprovetheCODremovalrateofwastewater.Whenm(assistantflocculant)∶m(flocculant)=40andthedosageofthecoagulantis2500-3000mg/L,theCODremovalrateofthewastewaterisabove80%.Keywords:amphotericchitosan;chemicaloxygendemand;flocculant;assistantflocculant;flocculatingproperty两性壳聚糖是一类分子结构中含两种带相反电性基团的特殊壳聚糖衍生物,典型的两性壳聚糖有羧甲基化壳聚糖季铵盐(CM-CTACTS)和季铵化