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为达到消毒目的,同时控制消毒副产物(DBPs)的生成,需要对有关水质的变量,如加氯量和接触时间、温度、pH和总有机碳(TOC)等的影响进行研究。本文探讨了在氯胺为残余消毒剂且接触时间较短的情况下,温度等水质变量对三卤甲烷(THMs)和卤代乙酸(HAAs)生成量的影响。结果表明,TOC和液氯接触时间对DBPs的影响最大,加氯量、pH和温度也影响DBPs的生成。有些变量的反应呈线性,有些则是非线性的。大多数情况下;THM浓度高于HAA浓度,相反情况也存在。应调查DBPs在不同条件下的生成量,从而确定用氯消毒的最佳方式,降低DBPs浓度。 相似文献
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二氧化氯消毒剂性能及其消毒副产物的毒性 总被引:1,自引:0,他引:1
论述了二氧化氯在饮用水消毒过程中对三卤甲烷形成的抑制、消毒副产物对健康的影响以及消毒副产物的去除方法。尽管二氧化氯及其消毒副产物在较高浓度时会对饮用者的健康产生不良的影响。但可以认为用于饮用水消毒的剂量(1.2—1.4mg/L)是安全的。 相似文献
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以北方某市受污染水源为研究对象,通过实验考察了高锰酸盐复合药剂(PPC)与氯联合控制消毒副产物-三卤甲烷(THMs)的效果.实验结果表明,1.0mg/L PPC可使预氯化过程中的THMs生成量降低14.1%,pH值为6.0时,PPC显著降低了预氯化工艺的THMs生成量,并且THMs生成量随pH值降低而减少;联合预氧化工艺的THMs生成量与单独预氯化相比降低了17.2%.因此PPC和氯联合可有效降低饮用水的THMs生成. 相似文献
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The presence of pesticides in drinking water poses a human health risk and disinfection can either exacerbate or reduce these health risks by producing by-products that are either more or less toxic than the parent compound. Human exposure to environmental pollutants usually is at low levels in nature, chronic, and often involves non-genotoxic mechanisms of cellular injury such as aberrant intercellular gap junctional communication (GJIC). Compounds toxic to GJIC are known to cause tumor promotion, neuropathy and teratogenesis. The non-genotoxic effects of atrazine, alachlor, carbofuran, 2,4-D and lindane and their ozonation and chlorination by-products were determined as a function of gap junction intercellular communication (GJIC) activity in F344-WB rat liver epithelial cells. Lindane did not react with either ozone or chlorine and was toxic to GJIC. All the other pesticides reacted with both ozone and chlorine to various degrees and the by-products formed from these pesticides were not significantly more toxic to GJIC than the parent compounds. 相似文献
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论文采用淋洗液在线发生离子色谱法测定水中的五种消毒副产物和溴离子。淋洗液自动发生装置在线产生高纯度KOH,配合阴离子捕获柱CR-ATC使用,大幅度降低了本底电导(0.2μs左右),对水中痕量亚氯酸盐、氯酸盐、溴酸盐、二氯乙酸、三氯乙酸以及溴酸盐的前驱物溴离子进行准确定性定量分析。KOH淋洗液的梯度淋洗,明显改善了6种目标离子与其他阴离子的分离效果,使整个检测过程简便、高效,本方法对亚氯酸盐、氯酸盐、溴酸盐、二氯乙酸、三氯乙酸、溴离子的检出限分别为0.46μg/L、0.72μg/L、0.50μg/L、0.81μg/L、0.68μg/L、0.51μg/L;加标回收率在88%~111%;精密度在0.66%~5.90%;具有良好的线性。 相似文献
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W. Emile Coleman Jean W. Munch H.Paul Ringhand William H. Kaylor Donald E. Mitchell 《臭氧:科学与工程》1992,14(1):51-69
Experiments were performed to evaluate disinfection by-products in model humic acid solutions which were ozonated at three different ozone to carbon levels and then chlorinated. These experiments were conducted in order to help understand whether the ozone/post-chlorination process alters the amount and type of mutagenic by-products formed, from those produced by chlorination of humic acid alone. Disinfection by-products were identified by gas chromatography/mass spectrometry (GC/MS). Samples of clarified and sand-filtered Mississippi River water at a pilotscale drinking water treatment plant in Jefferson Parish, Louisiana, that were ozonated and post-disinfected with chlorine, also were analyzed by GC/MS. A comparison of the by-products in the pilot plant study versus those in our laboratory study showed that similar compounds were produced. The effect of bromide ion in the pilot plant water on by-product formation also is discussed. 相似文献
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采用常规一深度处理工艺处理东太湖原水,对比砂滤前置与后置对各工艺流程出水消毒副产物生成潜能去除效果的影响。研究发现,无论砂滤前置还是后置,生物活性炭工艺对有机物都有着良好的去除效果,整套工艺出水COD和uV。的去除率分别稳定在74.2%~87.1%和75.0%~80.2%。两套工艺对二甲基亚硝胺生成潜能(NDMAFP)的去除效果没有明显差别,出水NDMAFP降低35%~41%。砂滤前置工艺对三卤甲烷生成潜能(THMFP)和卤乙酸生成潜能(HAAFP)的控制效果优于砂滤后置工艺,砂滤前置工艺活性炭单元出水和砂滤后置工艺砂滤单元出水的THMFP分别降低31.0%~37.4%和28.2%~35.3%,HAAFP分别降低20.0%~24.6%和16.3%~23.2%。 相似文献
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为改善固体消毒剂的流散性以及对芥子气模拟剂2-氯乙基乙基硫醚(2-CEES)的消毒能力,以环境友好的过氧化物单过氧邻苯二甲酸镁(MMPP)为芯材,以不同吸附材料为壁材,通过流化床包衣技术,制备了新型芯-壳结构复合消毒粉MgO/MMPP,Al_2O_3/MMPP,活性白土(HEAC)/MMPP,并以羟丙基甲基纤维素(HPMC)/MMPP为对照研究了复合消毒粉微观形貌、粒径、流散性能、稳定性和2-CEES的消毒能力等性质。结果表明,复合消毒粉在提高MMPP流散性的同时,表现出良好的热稳定性,且消毒能力有了较大提高,其中MgO/MMPP,Al_2O_3/MMPP对2-CEES的消毒率高于99%,反应产物主要为2-氯乙基乙基亚砜和2-氯乙基乙基砜。通过流化床制备的复合消毒粉比MMPP有更好的消毒能力,这为新型吸附反应型洗消剂的开发提供了技术支撑。 相似文献
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文中重点考察含碘水折点加氯过程中消毒副产物(DBPs)的生成特性,包括常规含碳类DBPs(C-DBPs)和新型含氮类DBPs(N-DBPs)。旨在通过探索不同碘离子浓度(I^-)、溴碘摩尔比(Br^-/I^-)、天然有机物(NOM)浓度以及pH条件下C-DBPs和N-DBPs的生成趋势,寻求一种最佳的氯投加方式,从而减少消毒副产物的生成。试验研究结果表明,当水中只存在I^-时,沿折点加氯曲线生成的C-DBPs和N-DBPs主要是三氯甲烷(TCM)和二氯乙腈(DCAN),且随着加氯量的增加,TCM和DCAN生成浓度均逐渐增加,折点以后浓度增加更明显。当加氯量一定时,随着I^-浓度的升高,TCM和DCAN生成量反而略有下降。而当水中同时含有Br^-、I^-时,折点加氯过程中会额外产生多种具有更高细胞毒性的溴代C-DBPs[二溴一氯甲烷(DBCM)、一氯二溴甲烷(CDBM)和三溴甲烷(TBM)]和溴代N-DBPs[一溴一氯乙腈(BCAN)和二溴乙腈(DBAN)]。随着Br^-/I^-增加,TBM和DBAN浓度逐渐升高并成为主要DBPs。随着NOM浓度升高,TCM和DCAN生成量增大并逐渐饱和。pH不仅会影响折点加氯过程中氯形态变化,还会影响DBPs的生成,其中pH值=6.0时TCM生成量最少,pH值=8.0时DCAN生成量最少。 相似文献
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通过对污水处理厂出水加氯消毒各种因素的分析,并经实验研究确定影响消毒效果的因素为pH、有机氮、COD、氨氮、水温等,其中pH为最主要影响因素,同时得出加氯消毒最佳水质条件。在实际生产中,可根据在线仪表显示的水质情况,来调节最佳投氯量。 相似文献