中压紫外对碘酸根的降解及后续氯胺化I-THM生成特性  

Photodegradation of iodate by medium-pressure UV irradiation and formation of I-THM in sequential chloramination

作　　者：张帆[1] 徐斌[1] 王震[1] 王安琪[1] ZHANG Fan;XU Bin;WANG Zhen;WANG An-qi(State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China)

机构地区：[1]同济大学环境科学与工程学院污染控制与资源化研究国家重点实验室,上海200092

出　　处：《中国环境科学》2017年第2期592-597,共6页China Environmental Science

基　　金：水体污染控制与治理科技重大专项水体污染控制与治理科技重大专项(2015ZX07406004)

摘　　要：以碘酸根为研究对象,研究中压紫外对碘酸根的降解速率,天然有机物及共存碘离子对其降解速率影响,在此基础上,采用氯胺消毒方式,考察溶液pH、氯胺投加量及溴离子浓度对碘代消毒副产物的生成影响.研究发现,饮用水中压紫外消毒工艺对碘酸根具有明显降解作用,其光反应产物为碘离子.降解过程符合拟一级反应动力学方程,中压紫外光强为8.5mW/cm^2时,其拟一级反应速率常数为(0.403±0.059)×10^(-3)s^(-1).水中天然有机物(NOM)可促进紫外光对碘酸根的降解,而初始碘离子浓度会抑制碘酸根降解.含碘酸盐原水经中压紫外光照射后,后续氯胺消毒工艺将大量产生碘代三卤甲烷(I-THMs).因此在采用中压紫外/氯胺联合消毒的净水工艺中,碘酸根转化后形成碘代消毒副产物的风险应当引起关注.Effects of Natural Organic Matter(NOM),iodide on the degradation of iodate by medium-pressure UV wereinvestigated.Effects of solution pH,chloramine dosage,and bromide concentration on the formation of iodinatedtrihalomethanes(I-THMs)during post-chloramination were also studied.It was found that iodate can be degraded bymedium pressure UV irradiation.The pseudo-first-order reaction rate constant was determined to be(0.403±0.059)×10-3s-1when the UV intensity was8.5mW/cm2.The reaction could be promoted by the addition of NOM but impeded bythe addition of iodide.I-THMs could be formed if water containing iodate was treated with UV/chloramination process.Therefore,special attention should be paid to iodate as a kind of I-THM precursor in drinking water treatment plants whenmedium-pressure UV/chloramination disinfection process was applied.

关 键 词：碘代消毒副产物 中压 紫外辐照 氯胺化 

分 类 号：X131.2[环境科学与工程—环境科学]