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/cm2时，其拟一级反应速率常数为(0.403±0.059)×10-3s-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 were investigated. Effects of solution pH, chloramine dosage, and bromide concentration on the formation of iodinated trihalomethanes (I-THMs) during post-chloramination were also studied. It was found that iodate can be degraded by medium pressure UV irradiation. The pseudo-first-order reaction rate constant was determined to be (0.403±0.059) ×10-3s-1 when the UV intensity was 8.5mW/cm2. The reaction could be promoted by the addition of NOM but impeded by the 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 when medium-pressure UV/chloramination disinfection process was applied.
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