铁盐预混凝对微滤膜污染的影响

《铁盐预混凝对微滤膜污染的影响》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、第40卷第10期北京工业大学学报Vol．40No．102014年10月JOUＲNALOFBEIJINGUNIVEＲSITYOFTECHNOLOGYOct．2014铁盐预混凝对微滤膜污染的影响王锦，罗东平，曹成艳(北京交通大学土木工程学院，北京100044)摘要:针对混凝－微滤工艺，为优化铁盐预混凝条件及揭示不同凝聚体特性对膜污染的影响，分析了三氯化铁(ferricchloride，FC)和聚合硫酸铁(polymericferricsulfate，PFS)在不同投加量(0.1、0.2、0.4、0.6mmol/L)和混凝pH(4.5、5.5、6.5、7.5)条件下对水中天然有机物－腐植酸的去

2、除率和膜污染的影响规律．实验结果表明:当酸性pH4.5～5.5电性中和机理为主时，PFS低投药量(0.1～0.2mmol/L)凝聚体颗粒大而密实，膜过滤中通量下降缓慢，膜污染程度轻，此时聚铁水解产物的高电荷比单铁更有利于电中和;中性pH6.5～7.5卷扫混凝时，FC高投药量(0.4～0.6mmol/L)缓解膜污染的作用更明显，此时单铁水解产物卷扫混凝形成凝聚体的颗粒粒径更大．可见，混凝凝聚体颗粒大小与结构特性，是膜污染的直接影响因素，大而密实的颗粒有利于增加膜通量，同时提高出水水质．关键词:混凝;微滤;腐植酸;Zeta电位;颗粒粒度;膜污染中图分类号:X254文献标志码:A文章编号:02

3、54－0037(2014)10－1547－07InfluenceofIronSaltsPre-coagulationonFoulingofMicrofiltrationMembraneWANGJin，LUODong-ping，CAOCheng-yan(SchoolofCivilEngineering，BeijingJiaotongUniversity，Beijing100044，China)Abstract:Tooptimizetheironpre-coagulationconditionandclarifytheinfluenceofdifferentaggregatescharact

4、eristicsonmembranefoulingforcoagulation-microfiltration(MF)process，pre-coagulationconditionsofferricchloride(FC)andpolymericferricsulfate(PFS)atdifferentcoagulantdosages(0.1，0.2，0.4，0.6mmol/L)andcoagulationpHvalues(4.5，5.5，6.5，7.5)wereanalyzedtorevealmembranefoulingmechanismsandhumicacidremoval．Ｒ

5、esultsshowthatunderacidicpH4.5－5.5ofelectricalneutralizationcoagulationcondition，thelowerPFSdosage(0.1－0.2mmol/L)hasthebettercoagulationeffect，whichtheagglomerateshavelargerparticlesizeandhigherfractaldimensionformorehighpositivechargeproducedbypolymericferrichydrolysisproductshaveanadvantageinch

6、argeneutralizationincomparisonwithFC．Thusmembranefluxdeclinationissloweddownandmembranefoulingisalleviated．UnderneutralpH6.5－7.5ofsweepcoagulation，thehigherdosage(0.4－0.6mmol/L)ofFCissuperiortoreducemembranefouling，ashydrolysisproductsofFCisliabletoproducelargerparticlesinsweepcoagulation．Particl

7、esizeandstructuralcharacteristicsofthecoagulationagglomeratesdirectlyaffectthemembranefouling，thelargerparticlesizeandhigherfractaldimensionaresuperiortoincreasemembranefluxandsimultaneouslyimprovewaterquality．Keywords