饮用水中亚硝胺类消毒副产物含量变化特征研究

Research on content changing characters of N-nitrosamine disinfection by-production in drinking water

与氯胺给水系统相伴生的亚硝胺污染风险已引起广泛关注,相关研究也推动了饮用水中亚硝胺类副产物标准的出台。以经过常规工艺处理的水厂出水为试验用水,借助GC-MS/MS对主体水、模拟管网水以及实际管网水中亚硝胺类消毒副产物含量进行了测定分析,得到了主体水与管网水中亚硝胺含量变动特征,分析了管网对消毒副产物迁移转化的影响作用。发现经过常规处理工艺净化后的出厂水以亚硝基二甲胺(NDMA)与亚硝基二乙胺(NDEA)为主要亚硝胺类副产物,管道污染与微生物滋生可产生亚硝胺生成前体物,从而增加亚硝胺类副产物生成风险。在管网运行中,建议采取调整消毒剂组成、降低含氯消毒剂一次投加浓度等手段,降低亚硝胺类副产物生成风险,提高饮用水安全水平。

N-nitrosamine induced drinking water pollution has aroused researchers'attentions,relevant researches have also promote the introduction of standards on N-nitrosamines in drinking water.The water treated by conventional water treated processes was used as the test water,the concentrations of N-nitrosamines in bulk water,simulated pipeline water,real pipeline water were determined by GC-MS/MS,changing characters of N-nitrosamines in bulk water and pipeline water were found,the impact of pipe wall on migration and transformation was further analyzed.It was found that nitroso-dimethylamine(NDMA)and nitroso-diethylamine(NDEA)were the two main N-nitrosamine disinfection by-products existing in the treated water,pipe wall pollution and micro-organism growth could produce the precursors of N-nitrosamine disinfection by-products,further elevating the risk of producing N-nitrosamine disinfection by-products.So it is suggested to lower the risk of producing N-nitrosamines by adjusting the disinfectant constitution and reducing one-time dosing concentration of chlorine-containing disinfectant,so as to improve the safety level of drinking water.