控制饮用水处理工艺及配水管网中卤乙酸的研究

研究了北京市第九水厂处理工艺过程中卤水乙酸的去除特性,并测定了五个水厂配水管网中卤乙酸的变化情况,结果表明：１传统水处理工艺对卤乙酸的去除率仅在２０％以下;活性炭对卤乙酸的去除效果较好,不同运行时期的炭床对其进行中的卤乙酸去除率为５０％￣８５％,去除的卤乙酸占预氯化后水厂进水中卤乙酸总量的４０％￣７０％,其去除作用包括活性炭的吸附和炭床中的生物分解,两者所去除的卤乙酸量基本相同。２配水管网中影响卤     

离子色谱法测定水中二氯乙酸和三氯乙酸

建立了饮用水中二氯乙酸(DCAA)和三氯乙酸(TCAA)的离子色谱检测方法。采用Diones 2000型离子色谱仪,直接进水样,进样体积为500μL,以10～45 mmol/L氢氧化钾溶液梯度淋洗,流速为1. 0 m L/min,30 min内完成检测。二氯乙酸、三氯乙酸的测定下限分别为0. 005和0. 010 mg/L,相对标准偏差5. 01%,回收率在95%～104%。该方法准确性高,适合检测地表水源水和出厂水中的二氯乙酸和三氯乙酸。     

离子色谱法测定水中7种阴离子

建立了离子色谱法同时测定水中7种阴离子的方法。样品过滤后,采用IonPac AS-19阴离子色谱柱分离,KOH溶液梯度淋洗,电导检测器检测水中氟离子、亚氯酸盐、溴酸盐、氯离子、硝酸盐、氯酸盐、硫酸盐的含量。7种阴离子线性关系良好r>0.998 8,加标回收率为91.6%¹08%,相对标准偏差(RSD)为0.13%108%,相对标准偏差(RSD)为0.13%⁸.8%。样品前处理简便,分离度和加标回收率均较高,适用于水中7种阴离子的测定。     

离子色谱法测定饮用水中的二氯乙酸和三氯乙酸

建立了用离子色谱法检测饮用水中二氯乙酸和三氯乙酸的检测方法,采用3.60mmol/L Na_2CO_3和10.00%甲醇混合溶液作为淋洗液,进样体积为250.00μL,流速0.80mL/min,经阴离子交换柱,由电导检测器检测,测得饮用水中二氯乙酸和三氯乙酸的检出限为4.93μg/L和14.1μg/L,自来水中加标回收率在89.2%~92.3%之间,方法简便快捷,适用于饮用水中二氯乙酸和三氯乙酸的定量测定。     

离子色谱法同时测定生活饮用水中的卤乙酸和草甘膦

利用离子色谱法同时测定饮用水中的二氯乙酸(DCAA)、三氯乙酸(TCAA)和草甘膦(PMG).结果表明,该方法的相关系数R2＞0.999 0,高中低浓度加标回收率为84.0％～104.0％,二氯乙酸、三氯乙酸和草甘膦的检出限分别为6.3,7.9和16.3μg/L.同时还分析了梯度淋洗条件和干扰离子等对各组分分离测定的影响.     

饮用水中卤乙酸的测定方法

自从1980年二氯乙酸（DCAA）和三氯乙酸（TCAA）被首次报告出现在饮用水中之后,大量的研究表明加氯消毒后的饮用水中卤乙酸（HAAs)是普遍存在的,并且某些种类的卤乙酸的致癌风险性高于三卤甲烷（THMs)。目前,卤乙酸问题已经国外的高度重视,美国国家环境保护局在1993年提出的消毒剂与消毒副产物准则（Disinfectants and Disinfection By-Product Rule)中,就提出对卤乙酸的浓度加以规定。而我国对卤乙酸问题的研究起步较晚,对卤乙酸的测试工作还未能全面展开。现本文把国外对饮用水中卤乙酸的测试方法介绍我国水质分析人员,以促进我国给水工作者加强对卤乙酸问题的研究工作。     

水中腐殖酸氯化生成卤代苯醌类消毒副产物的特性

采用腐殖酸配水,研究了氯化消毒过程中二氯对苯醌（DCBQ）、二溴对苯醌（DBBQ）、2,3-二溴-5,6-二甲基对苯醌（DBDMBQ）、四溴对苯醌（TBBQ）等卤代苯醌（HBQs）类消毒副产物的生成特性和影响因素。结果表明,腐殖酸氯化生成DCBQ和DBBQ的产率高于DBDMBQ和TBBQ。随着反应时间的增加,4种HBQs的生成量均呈现先快速升高之后保持稳定并稍有下降的趋势;随着温度的升高,HBQs的生成量呈增加趋势;弱酸性条件有利于HBQs的生成;在有效氯投加量为3～30mg/L范围内,DCBQ与DBBQ的生成量随加氯量的增加而增加,TBBQ与DBDMBQ的生成量随加氯量的增加先增加后减少;随着DOC浓度的增加,HBQs的生成量逐渐增加,其中分子质量<1 ku组分的单位质量有机物HBQs生成势最高。     

二氧化氯消毒对饮用水中有机卤代物形成的影响

二氧化氯消毒对饮用水中有机卤代物形成的影响①饮用水液氯消毒产生的氯仿等有机卤代物对人体的危害已引起人们的普遍关注，各国学者和专家纷纷致力于饮用水安全氯化消毒技术的研究。美国环保局推荐ＣｌＯ２消毒做为控制水中三卤甲烷（ＴＨＭ）最适宜的措施，并将它列为取...     

天津城市供水系统中卤乙酸含量的研究

考察了天津市城市供水系统中卤乙酸的含量及其变化规律.结果表明,各自来水厂的出厂水及管网水中的二氯乙酸和三氯乙酸含量均远远低于<生活饮用水卫生标准>(GB 5749-2006)规定的限值;自原水进入自来水厂至最终到达用户自来水龙头的整个过程,水中的二氯乙酸和三氯乙酸含量呈快速上升--保持平稳--快速下降的变化趋势,其中滤后水中的卤乙酸含量最接近或达到峰值;采用预氯化工艺会促进卤乙酸的生成,水温与卤乙酸的生成呈正相关.     

卤乙酸分析方法(U.S.EPA)的改进

对U.S.EPA Method552.3卤乙酸分析方法进行了改进。参照原方法中液-液微萃取、酸化甲醇衍生化技术,研究了以高纯水代替MTBE作溶剂配制贮备标准液、气相色谱/质谱联用的适宜检测分析条件和控制过程。结果表明,在所确立的检测条件下,样品运行时间短,内标、HAAs组分峰在谱图上能够得到很好的分辨。低、中、高三个浓度水平水样的HAAs回收率为82%~103%,方法检测限:二氯乙酸为0.72μg/L、三氯乙酸为0.44μg/L。用水作溶剂配制的贮备标准液4℃下贮存时间为两个月。     

Speciation and variation in the occurrence of haloacetic acids in three water supply systems in England

An investigation into the speciation and occurrence of nine haloacetic acids (HAAs) was conducted during the period of April 2007 to March 2008 and involved three drinking water supply systems in England, which were chosen to represent a range of source water conditions; these were an upland surface water, a lowland surface water and a groundwater. Samples were collected seasonally from the water treatment plants and at different locations in the distribution systems. The highest HAA concentrations occurred in the upland surface water system, with an average total HAA concentration of 21.3 μg/L. The lowest HAA levels were observed in the groundwater source, with a mean concentration of 0.6 μg/L. Seasonal variations were significant in the HAA concentrations; the highest total HAA concentrations were found during the autumn, when the concentrations were approximately two times higher than in winter and spring. HAA speciation varied among the water sources, with dichloroacetic acid and trichloroacetic acid dominant in the lowland surface water system and brominated species dominant in the upland surface water system. There was a strong correlation between trihalomethanes and HAAs when considering all samples from the three systems in the same data set (r ²=0.88); however, the correlation was poor/moderate when considering each system independently.     

纳滤控制饮用水中消毒副产物的研究进展

纳滤(NF)膜孔径小,能截留较低分子质量的有机物,同时表面带电,对水中有机物具有较好的去除效果。探讨了纳滤对饮用水中消毒副产物及其前体物的去除机理及效果。结合国内外的研究现状,重点阐述了纳滤膜的特性及分离机理,在此基础上介绍了纳滤膜对典型和新兴消毒副产物的控制效果。     

Haloacetic acids and trihalomethanes in finished drinking waters from heterogeneous sources

Trihalomethanes (THM) and haloacetic acids (HAA) are the most frequent chlorination by-products (CBP) in finished drinking waters. Traditionally, THM have been used as surrogates for CBP although the quantitative association between THM and other CBP is not well established. This problem is addressed in the present study from the analysis of THM and HAA in drinking water samples from four Spanish regions, representing areas with very different CBP composition, e.g. between 86 and 8.0 microg/l of THM and 50-3.0 microg/l of HAA.The resulting dataset exhibit a statistically significant correlation between total THM and HAA (Pearson's correlation coefficient, r(p)=0.815,p<0.0005). Furthermore, specific HAA are highly correlated with specific THM or their combinations. Accordingly, multivariate linear regression analysis of the concentrations observed show that the levels in total and specific HAA can be predicted from the THM content. These results are relevant for epidemiological studies on health effects from CBP exposure since they usually involve comparison of populations consuming waters of very distinct quality.     

含氮消毒副产物卤代酰胺的生成特性与控制研究进展

卤代酰胺(haloamides)具有极强的致癌、致崎和致突变性,是饮用水处理领域开始关注的一种新型含氮卤代消毒副产物.这类物质分子质量小、结构简单、可水解,具有很强的极性和亲水性,可广泛存在于消毒后的出厂水中.卤代酰胺的产生受到温度、pH值、消毒剂含量的影响,但生成机制非常复杂,尚未有相关理论能完全解释其产生规律.鉴于其较强的"三致"特性,对它的物理特性、产生条件及控制手段进行研究是目前消毒副产物领域的一个重要方向.介绍了卤代酰胺的特性、检测方法,对其控制手段的最新研究进展进行了重点说明,指出通过控制其前体物的方法来控制卤代酰胺的产生是该领域的研究重点.     

Impact of source waters,disinfectants, seasons and treatment approaches on trihalomethanes in drinking water: a comparison based on the size of municipal systems

This study compares concentrations of trihalomethanes (THMs) in municipal water for 2001–2007 from the small and large systems in two provinces in Canada (Newfoundland and Quebec) based on source waters, disinfectants, seasons and treatment approaches. Approximately 71 and 94%, respectively, of the municipal systems in Quebec and Newfoundland are small systems (serving fewer than 3000 people). The small systems serve approximately 8.6% (0.57 million) and 44.1% (0.18 million) of the populations in Quebec and Newfoundland, respectively. Concentrations of THMs and its variability are much higher in the small systems (Quebec: 0–941 μg/L; Newfoundland: 0–875 μg/L) than in the systems with populations 10 000 or more (Quebec: 0–364 μg/L; Newfoundland: 2.3–205 μg/L). The study reveals that the differences in THMs between the small and medium/large systems are because of different types of source waters, treatments, disinfection strategies and seasons. The results emphasize that regulatory agencies must focus more on the occurrence of DBPs in small systems and identify strategies to reduce their levels in drinking water.     

AutoPrep离子色谱法检测饮用水中痕量NO3-和NO2-

利用戴安公司全新的AutoPrep自动样品前处理技术，首次提出将OnGuard SPE前处理小柱在线使用的概念，对饮用水中的大部分氯离子进行在线去除的同时，还可对其中的亚硝酸盐和硝酸盐进行快速、准确的定量。该方法选用了自动在线水纯化装置CIRA和OnGuard Ag小柱，运用阀切换技术实现自动进样；适宜的色谱条件为：高容量氢氧化物选择性IonPac AS18阴离子交换色谱柱，淋洗液自动发生装置在线产生KOH进行梯度淋洗，抑制型电导检测；相关方法参数：对于自来水和瓶装水，亚硝酸盐和硝酸盐的检出限（S／N=3）分别为17．8μg/L和25．6μg/L，线性相关系数分别为0．9997和0．9999，RSD〈5％，加标回收率〉92％。该方法具有自动化程度高、操作简单、重现性好、节约时间、成本低廉和对环境友好的特点。此外，研究了前处理小柱的连续使用次数，并对在线和离线的除氯效果进行了比较，认为在线除氯可节约检测成本，且对除氯效果无太大影响。     

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.