摘要
消毒已成为水处理系统中不可或缺的一部分,但水中溶解性有机质(DOM)与消毒剂反应时会不可避免地产生有毒有害的消毒副产物(DBPs),从而影响饮用水安全。为探究水处理系统中曝气生物滤池(BAF)对DOM去除与DBPs生成的影响,以某水厂的BAF单元为研究对象,采用傅里叶变换离子回旋共振质谱(FT-ICR MS)结合光谱技术和色谱质谱联用等方法,探究了BAF对DBPs及其前体物的控制机制,并通过质量差网络分析探究了DBPs的生成途径。结果表明:BAF去除了部分进水中的类芳香蛋白质,降低了消毒后产生的三卤甲烷、卤乙酸和卤乙腈的浓度,但消毒后卤代硝基甲烷的浓度有所升高,这些常规DBPs仅能解释不到60%的总有机氯化物的浓度;在分子水平上,BAF处理倾向于将低氧化程度和高饱和度的分子转化成高氧化程度和高不饱和度的分子,导致后续消毒过程中生成的低不饱和度DBPs更少,高不饱和度DBPs更多,这可能会促进水厂后续的混凝沉淀单元对DBPs及其前体物的去除;质量差网络分析显示,氯取代(+Cl—H)、氯加成(+HClO)和羟基化与氯取代(+ClO—H)这3种反应类型是生成DBPs的最主要途径,参与加成反应的DBPs前体物的不饱和度要比参与取代反应的DBPs前体物高。研究结果可为饮用水消毒副产物控制提供基础参考信息。
Disinfection has become an indispensable part of water treatment systems,but dissolved organic matter(DOM)in water inevitably produces toxic and harmful disinfection by-products(DBPs)when reacting with disinfectants,thereby affecting the safety of drinking water.To explore the influence of biological aerated filter(BAF)on the removal of dissolved organic matter(DOM)and the generation of disinfection byproducts(DBPs),we used Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)combined with optical spectrum technology and chromatography-mass spectrometry to comprehensively investigate the effect of BAF on DBPs and their precursors,and the formation pathways of DBPs were clarified through mass difference network analysis.The results show that BAF partially removes the aromatic proteins in the influent,and reduces the concentrations of trihalomethanes,haloacetic acids and haloacetonitriles produced after disinfection,but increases the concentrations of halonitromethanes.These conventional DBPs account for less than 60%of the total organic chloride concentration.At the molecular level,BAF tends to convert molecules with a low oxidation degree and high saturation into molecules with a high oxidation degree and high unsaturation,resulting in less DBPs with low unsaturation and more DBPs with high unsaturation during subsequent chlorination,which may facilitate the removal of DBPs and their precursors in the subsequent coagulation and sedimentation unit of the water plant.Mass difference network analysis shows that chlorine substitution(+Cl—H),chlorine addition(+HClO)and hydroxylation and chlorine substitution(+ClO—H)are the dominant pathways to generate DBPs,and the unsaturation of DBPs precursors participating in addition reaction is higher than that of the precursors participating in substitution reaction.This study can provide basic information for the DBPs control of drinking water.
作者
孙鹏
王文冰
何航
张伟军
SUN Peng;WANG Wenbing;HE Hang;ZHANG Weijun(Ningcia Environmental Protection Group Co.,Ltd.,Yinchuan 750004,China;School of Environmental Studies,China University of Geosciences(Wuhan),Wuhan 430078,China;Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science,China University of Geosciences(Wuhan),Wuhan 430078,China;Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)
出处
《安全与环境工程》
CAS
CSCD
北大核心
2024年第1期249-259,共11页
Safety and Environmental Engineering
基金
宁夏回族自治区银川市科技创新重点项目(2022ZDGX08)。
