氯胺消毒过程中碘代三卤甲烷生成的影响因素

碘代消毒副产物的"三致"特性远高于氯代和溴代消毒副产物,是近年来饮用水领域颇受关注的一类新兴消毒副产物。以微污染原水为研究对象,系统研究了其在氯胺消毒条件下碘代三卤甲烷类消毒副产物生成的影响因素。研究发现,在原水中存在一定浓度碘离子的条件下,采用氯胺消毒可产生较高浓度的碘代三卤甲烷类消毒副产物,其中以三碘甲烷为主;碘代三卤甲烷的生成总量随着反应时间的增加而增加;碘代三卤甲烷的生成量和组成受氯胺投加量的影响较大,在氯胺投加量较低的情况下主要生成三碘甲烷和一溴二碘甲烷,在氯胺投加量较高的情况下生成一氯二碘甲烷、二氯一碘甲烷、一溴二碘甲烷和三碘甲烷四种碘代三卤甲烷;碘代三卤甲烷的生成总量以及三碘甲烷在总碘代三卤甲烷中的比例随着碘离子浓度的增加而提高;总体上,氯胺化过程中碘代三卤甲烷的生成总量随着pH值的升高而增加。     

饮用水中消毒副产物卤乙腈、卤代硝基甲烷和亚硝胺的研究现状

饮用水中消毒副产物如卤乙腈（HANs）、卤代硝基甲烷（HNMs）和亚硝胺（NAs）等含氮消毒副产物（N-DBPs）由于其高细胞毒性和基因毒性,以及“三致毒性”被广泛关注和研究。本文简述了卤乙腈（HANs）、卤代硝基甲烷（HNMs）和亚硝胺（Nas）的国内外研究情况、分布分类、毒性危害、检测方法、生成控制和去除方法,为保障我国饮用水水质安全提供文献参考。     

水中卤代苯醌类消毒副产物分析方法研究进展

消毒副产物是水在消毒过程中消毒剂与天然有机物反应生成的一类有害副产物.卤代苯醌类消毒副产物在水中以痕量水平被检出,近年来研究发现其与膀胱癌的发病有潜在关联.综述了水中卤代苯醌类消毒副产物分析的样品前处理技术及仪器分析方法,包括液液萃取、分散液液微萃取、固相萃取、固相微萃取等样品前处理技术及气相色谱-质谱联用、高效液相色谱、超高效液相色谱、液相色谱-质谱联用技术等仪器分析方法.介绍了以上方法在检测实际水样中卤代苯醌类消毒副产物的应用,并展望了卤代苯醌类消毒副产物检测技术的未来发展方向.     

消毒副产物三氯甲烷与膀胱癌的关系

<正>氯化消毒(chlorination)是饮用水加工过程中使用最广泛的消毒方式。然而,氯化消毒过程中可产生对健康有害的物质一消毒副产物(disinfection byproducs,DBPs)。消毒副产物主要包括三卤甲烷(trihalomethanes,THMs)、卤代乙酸(haloacefic acids,HAAs)、卤代乙腈(haloaceton itriles,HAN)等。毒理学研究显示DBPs具有遗传毒性、致突变性、细胞毒性、生殖发育毒性和致癌性。膀胱癌是指发生在膀胱黏膜上的恶性肿瘤。是泌尿系统最常见的恶性肿瘤,也是全身十大常见肿瘤之一。有研究表明消化副产物的暴露与膀胱癌     

磺胺甲口恶唑氯化消毒副产物生成势及影响因素研究

研究了东太湖水源水中典型抗生素磺胺甲口恶唑(SMX)氯化消毒副产物(DBPs)生成势及影响因素。结果表明:SMX经氯化反应后可生成三卤甲烷、卤乙腈、卤乙酸、卤乙醛、卤代丙酮等多种DBPs,且加氯量、反应时间、反应温度、pH值等因素均会影响其DBPs生成势。当溶液中存在溴离子时,SMX氯化生成的三卤甲烷、卤乙酸的组分及生成量有较大变化,且随着溴离子浓度的增大,一些氯代消毒副产物(Cl-DBPs)会转化为具有更高毒性的溴代消毒副产物(Br-DBPs)。     

二氧化氯预氧化控制卤代消毒副产物研究

针对Z市某水厂卤代消毒副产物季节性超标风险,开展以二氧化氯替代液氯进行预氧化处理的中试研究。结果表明,在二氧化氯最佳投加量(0.6~0.9 mg/L)条件下,该方法可有效控制夏季高温时三卤甲烷超标风险,保证其副产物满足标准限值要求。同时,加入二氧化氯可强化对有机物、藻类等去除效果。本文研究结果可为二氧化氯预氧化的应用提供技术参考。     

含氮消毒副产物的生成机理与富集技术研究进展

含氮消毒副产物（N-DBPs）作为饮用水中一类新兴的消毒副产物,因其与含碳消毒副产物（C-DBPs）相比具有更强的“三致”（致畸、致癌、致突变）作用,且由于国内标准法规未对其浓度含量进行限定及监测,因此其危害更加隐蔽,近年来受到广泛关注。对卤乙腈（HANs）、卤乙酰胺（HAcAms）、卤代硝基甲烷（HNMs）、亚硝胺（NMs）等新型N-DBPs的毒理性质、形成机理及控制技术进行了梳理归纳,总结了现有不同N-DBPs的前处理技术及其原理。对新材料在前处理富集过程中的应用前景进行了展望,以期为实现饮用水N-DBPs的痕量检测及有效监测提供参考。     

成都市饮用水中消毒副产物的变化研究

以成都市第六水厂的工艺出水和管网水为测试对象，研究了常规处理工艺对消毒副产物及其前体物的去除特性，分析了消毒副产物在管网中的变化规律，并且提出了控制饮用水中消毒副产物的对策。研究结果表明：①成都市自来水中消毒副产物的主要成分为卤乙酸；②常规处理工艺对三卤甲烷前体物和卤乙酸前体物均有很好的去除效果(去除率为50％左右)，但对卤乙酸(HAAs)和三卤甲烷(THMs)却无去除作用；③预氯化产生的THMs、HAAs分别占管网中此类物质最高浓度的22％和50％；④应该以管网入口处三氯甲烷、卤乙酸的浓度作为整个管网的控制指标。     

现场制备次氯酸钠对饮用水消毒效果的试验研究

针对次氯酸钠发生器、二氧化氯发生器及成品次氯酸钠消毒后的消毒效果和消毒副产物的生成情况进行研究,并对成品次氯酸钠溶液进行了特性试验,分析了三种消毒方式的安全管理和运行成本.结果表明:三种消毒方式消毒杀菌效果没有显著差异,但二氧化氯与次氯酸钠消毒产生的消毒副产物种类不同,次氯酸钠消毒副产物多为三卤甲烷类和卤乙酸等,二氧化氯消毒主要产生氯酸盐和亚氯酸盐.次氯酸钠发生器制备的次氯酸钠溶液与成品次氯酸钠溶液在消毒副产物水平上没有显著差异.成品次氯酸钠溶液中的溴酸盐含量明显高于次氯酸钠发生器制备溶液,且随着储存时间的增加,成品次氯酸钠溶液存在有效氯衰减和氯酸盐含量增加的现象.     

关于测定饮用水中三卤甲烷含量样品的保存条件及最佳检测时间的研究

三卤甲烷是饮水氯化消毒过程中的主要副产物,其含量的准确测定对消毒副产物产生情况的评价有重要意义。三卤甲烷具有挥发性,不够稳定,样品采集后需要采取适当的方法进行保存并在一定时间范围进行测定方可获得准确的检测结果。本文通过实验对保存剂及保存方式进行研究,筛选出最佳保存条件及最佳检测时间。     

Potential impact of chlorination of Sandy bottom swimming areas on drinking water sources

The concentrations of trihalomethanes and haloacetic acids, disinfection by‐products (DBPs) of chlorine, were measured in sandy bottom swimming areas to determine their potential impact on surface and ground water that are sources of drinking water. Total trihalomethanes and individual haloacetic acid concentrations in several swimming area samples were higher than the drinking water standards (current and proposed). Individual trihalomethanes (except bromoform) also exceeded ground and surface water release standards. No release standard exists for haloacetic acids. The DBPs, while exceeding standards, would be diluted by the ground water and microbially degraded prior to reaching the drinking water plant. So while DBPs from swimming areas contributed to groundwater concentrations, the current drinking water standards could still be met using source waters impacted by chlorinated swimming areas. It is suggested, though, that any release of chlorinated DBPs to surface and ground water be minimized to obtain the highest quality water sources for drinking water.     

济南市供水消毒副产物的变化研究

选取济南市主要的三个地表水厂为研究对象,分析了消毒副产物在管网中的变化规律,并提出了控制饮用水中消毒副产物的对策。研究结果表明,济南市饮用水中的消毒副产物主要是三卤甲烷,温度和余氯是管网中控制消毒副产物和TOC浓度的重要因素。     

饮用水中氯化消毒副产物的控制研究进展

探讨了DBPs的形成机理及其种类,然后介绍了DBPs对人体的健康风险,并总结了目前国内外控制DBPs的方法,为饮用水高效安全消毒技术的进一步研究提出了意见和建议。     

The impact of bromide on the formation of neutral and acidic disinfection by-products (DBPs) in Mediterranean chlorinated drinking water

By using the Grob closed loop stripping analysis technique a wide variety of disinfection by-products (DBPs) was determined, in finished drinking water of 15 important cities of Greece distributed in the southern, northern, west continental land and in the islands of Aegean and Ionian Seas. Trihalomethanes, haloacetonitriles, haloacetic acids, chloropicrin, halogenated ketons and chloral hydrate were the main DBPs determined. In chlorinated drinking water of coastal cities brominated DBPs were most abundant than their chlorinated homologues due to the higher bromide concentration in raw waters of these areas. Factor analysis with principal component extraction of the results demonstrated a clear differentiation between the examined drinking waters on the basis of their DBPs content and vicinity to the sea.     

Chlorination disinfection by-products, public health risk tradeoffs and me

Since 1974 when trihalomethanes (THMs) were first reported as disinfection by-products (DBPs) in drinking water, there has been an enormous research effort directed at understanding how DBPs are formed in the chlorination or chloramination of drinking water, how these chlorination DBPs can be minimized and whether they pose a public health risk, mainly in the form of cancer or adverse reproductive outcomes. Driven by continuing analytical advances, the original DBPs, the THMs, have been expanded to include over 600 DBPs that have now been reported in drinking water. The historical risk assessment context which presumed cancer could be mainly attributed to exposure to environmental carcinogens played a major role in defining regulatory responses to chlorination DBPs which, in turn, strongly influenced the DBP research agenda. There are now more than 30 years of drinking water quality, treatment and health effects research, including more than 60 epidemiology studies on human populations, directed at the chlorination DBP issue. These provide considerable scope to reflect on what we know now, how our understanding has changed, what those changes mean for public health risk management overall and where we should look to better understand and manage this issue in the future.     

臭氧/氯消毒中藻类有机物生成消毒副产物的特征

饮用水源地藻华会释放大量藻类有机物(AOM),AOM与氯消毒剂反应生成的消毒副产物(DBPs)会给饮用水用户带来不容忽视的健康风险。为此,探究了臭氧/氯消毒对AOM结构和DBPs生成的影响。结果表明,臭氧氧化能有效去除AOM中芳香蛋白和酚类、叶绿素a、藻蓝蛋白结构物质,但是对腐殖酸类结构的去除效果相对较差。DBPs生成总量随臭氧投加浓度的升高而增加,其中主要是三氯甲烷(TCM);卤代乙腈和卤代酮的生成总量随臭氧投加浓度的变化趋势不明显。延长臭氧接触时间会明显增加1 h氯化中TCM的生成量,氯化24 h时DBPs生成总量与臭氧接触时间无关。在臭氧/氯消毒过程中,AOM的DBPs生成潜能低于天然有机物(NOM)。AOM有利于一溴一氯乙腈的生成,而NOM会生成更多的二氯乙腈。     

Disinfection by-products (DBPs) in drinking water and predictive models for their occurrence: a review

Disinfection for drinking water reduces the risk of pathogenic infection but may pose chemical threat to human health due to disinfection residues and their by-products (DBPs) when the organic and inorganic precursors are present in water. More than 250 DBPs have been identified, but the behavioural profile of only approximately 20 DBPs are adequately known. In the last 2 decades, many modelling attempts have been made to predict the occurrence of DBPs in drinking water. Models have been developed based on data generated in laboratory-scaled and field-scaled investigations. The objective of this paper is to review DBPs predictive models, identify their advantages and limitations, and examine their potential applications as decision-making tools for water treatment analysis, epidemiological studies and regulatory concerns. The paper concludes with a discussion about the future research needs in this area.     

Degradation of trichloronitromethane by iron water main corrosion products

Halogenated disinfection byproducts (DBPs) may undergo reduction reactions at the corroded pipe wall in drinking water distribution systems consisting of cast or ductile iron pipe. Iron pipe corrosion products were obtained from several locations within two drinking water distribution systems. Crystalline-phase composition of freeze-dried corrosion solids was analyzed using X-ray diffraction, and ferrous and ferric iron contents were determined via multiple extraction methods. Batch experiments demonstrated that trichloronitromethane (TCNM), a non-regulated DBP, is rapidly reduced in the presence of pipe corrosion solids and that dissolved oxygen (DO) slows the reaction. The water-soluble iron content of the pipe solids is the best predictor of TCNM reaction rate constant. These results indicate that highly reactive DBPs that are able to compete with oxygen and residual disinfectant for ferrous iron may be attenuated via abiotic reduction in drinking water distribution systems.     

Breakpoint chlorination and free-chlorine contact time: implications for drinking water N-nitrosodimethylamine concentrations

North American drinking water utilities are increasingly incorporating alternative disinfectants, such as chloramines, in order to comply with disinfection by-product (DBP) regulations. N-Nitrosodimethylamine (NDMA) is a non-halogenated DBP, associated with chloramination, having a drinking water unit risk two to three orders of magnitude greater than currently regulated halogenated DBPs. We quantified NDMA from two full-scale chloraminating water treatment plants in Alberta between 2003 and 2005 as well as conducted bench-scale chloramination/breakpoint experiments to assess NDMA formation. Distribution system NDMA concentrations varied and tended to increase with increasing distribution residence time. Bench-scale disinfection experiments resulted in peak NDMA production near the theoretical monochloramine maximum in the sub-breakpoint region of the disinfection curve. Breakpoints for the raw and partially treated waters tested ranged from 1.9:1 to 2.4:1 (Cl(2):total NH(3)-N, M:M). Bench-scale experiments with free-chlorine contact (2h) before chloramination resulted in significant reductions in NDMA formation (up to 93%) compared to no free-chlorine contact time. Risk-tradeoff issues involving alternative disinfection methods and unregulated DBPs, such as NDMA, are emerging as a major water quality and public health information gap.     

Formation, adsorption and separation of high molecular weight disinfection byproducts resulting from chlorination of aquatic humic substances

A significant portion of the unidentified disinfection byproducts (DBPs) in chlorinated drinking water can be attributed to high molecular weight (MW)-chlorinated DBPs (above 500 Da) that may have adverse health effects. In this work, issues on the formation, adsorption and separation of high MW-chlorinated DBPs were investigated by introducing radioactive (36)Cl into humic substance samples. The results show that the amount of high MW-chlorinated DBPs during chlorination decreased with the increase of contact time from 1 to 120 h, increased with the increase of pH from 5.5 to 9.5, and was less in the ultrafiltered samples from Suwannee River fulvic acid than from Suwannee River humic acid. The high MW-chlorinated DBPs were found to be effectively adsorbed by activated carbon and be possibly reduced to Cl(-) by activated carbon, but not to be readily desorbed from the activated carbon. Those high MW-chlorinated DBPs were demonstrated to be incapable of resolution into discrete peaks by any of the three liquid chromatography columns studied. The significant implications of these results are discussed.