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为了降低饮用水在氯消毒过程中产生的消毒副产物(DBPs)溴氯乙腈(BCAN)对人体带来的健康危害,采用Fe/Cu催化还原的方法降解饮用水中低浓度的BCAN,考察了BCAN的降解效果和其影响因素,探讨了其降解机制及动力学规律.结果表明,Fe/Cu具有更强的还原降解BCAN的能力,与零价铁相比,Fe/Cu(质量比为10∶1)的降解效率是其1.5倍.随着Fe/Cu投加量的增加,BCAN的去除率有明显的提高,对于初始浓度为20μg·L-1的BCAN溶液,当Fe/Cu(质量比为10∶1)投加量由5g·L-1增加到10 g·L-1,反应150 min后,去除率由51.1%增加到89.5%.BCAN降解效率随着温度的升高逐渐提高,BCAN初始浓度的变化对Fe/Cu去除BCAN的去除效果影响不大,Fe/Cu降解BCAN符合一级反应动力学规律. 相似文献
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以TiO2/Ti薄膜电极为阳极、石墨电极为阴极、饱和甘汞电极为参比电极,设计了一种新型的双槽光电化学协同催化反应器,考察了阴极电位、反应时间、电解质浓度、溶液pH值等因素对甲基橙降解效果的影响.结果表明,电解质浓度对甲基橙的降解脱色效果影响不明显,而阴极电位、溶液pH值和反应时间则影响显著;色度为200度的甲基橙溶液,在阴极电位(Ec)为-0.6V、阴极槽初始pH3.0和阳极槽初始pH5.6、反应90min的条件下,阴极槽和阳极槽中甲基橙的脱色率分别为98.3%和51.3%,与仅靠TiO2/Ti薄膜阳极对有机物进行催化降解的“双槽单效”光电催化反应器相比,对甲基橙的催化氧化降解效率显著提高.降解前后的紫外-可见吸收光谱的变化表明,该双槽光电化学协同催化反应器不但可以同时使阴、阳两槽中的甲基橙脱色,且其苯环结构也被降解和矿化. 相似文献
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研究了外加电压、初始浓度对电化学耦合膜工艺去除饮用水中卡马西平(CBZ)效果的影响.结果表明,CBZ初始浓度为100μg/L的条件下,随着电压的升高,电化学耦合膜工艺对CBZ的去除率逐渐增加,在外加电压为2V,电化学耦合膜工艺对CBZ的去除率达到88.0%;外加电压为2.0V的条件下,CBZ初始浓度为50~500μg/L时,电化学耦合膜对CBZ的去除率均达到85%以上.而与粉末活性炭/微滤膜(PAC/MF)工艺的比较可知,电化学耦合膜工艺的去除效果更为稳定,运行成本也更低.考察了水中的离子强度和腐殖酸对电化学耦合膜工艺去除CBZ效果的影响.结果表明,由于对系统中·OH的竞争作用,离子强度的增大及腐殖酸浓度的提高将抑制CBZ去除. 相似文献
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研究了一种电化学氢自养与硫自养集成去除饮用水中硝酸盐的方法,将2种自养反硝化集成,既可减少以硫作为电子供体产生的SO4^2-,也可以使硫自养反硝化产生的H^ 作为电化学产氢的前驱物。同时,在硫自养段可不添加调pH的CaCO3,避免了出水的硬度升高。试验结果表明,在反应器的水力停留时间(HRT)为1.9-5h,最小电流相应为3-16mA时,NO3^--N去除率达90%以上,出水中NO3^--N和SO4^2-浓度分别低于3.0mg/L和170mg/L,NO2^--N未检出,硫段和电氢段出水pH值均维持在中性附近。 相似文献
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Dechlorination of disinfection by-product monochloroacetic acid in drinking
water by nanoscale palladized iron bimetallic particle 总被引:1,自引:0,他引:1
Nanoscale palladized iron(Pd/Fe)bimetallic particles were prepared by reductive deposition method.The particles were characterized by X-ray diffraction(XRD),X-ray fluorescence(XRF),scanning electron microscope(SEM),transmission electron microscope(TEM),and Brunauer-Emmett-Teller-nitrogen(BET-N_2)method.Data obtained from those methods indicated that nanoscale Pd/Fe bimetallic particles containedα-Fe~0.Detected Pd to Fe ratio by weight(Pd/Fe ratio)was close to theoretical value. Spherical granules with di... 相似文献
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卤代苯醌(HBQs)是一类新型的消毒副产物,广泛存在于国内外饮用水中,与膀胱癌高度相关.由于我国对HBQs的研究时间不长,因此,对饮用水中HBQs的研究不够充分.本研究对天津市某自来水厂处理工艺出水及供水系统中HBQs的浓度进行了调查,共检出3种HBQs(二氯苯醌、二溴苯醌及二氯甲基苯醌),首次报道了我国饮用水中二氯甲基苯醌的浓度.此外,由于HBQs在水中易发生水解反应,识别HBQs在不同pH值和温度下的水解特性可以更好地描述HBQs的环境行为.因此,本研究以4种HBQs为代表,考察了HBQs在不同pH值和温度下的水解特性.结果表明,偏碱性的环境和较高的温度有利于HBQs的水解,氯代苯醌的稳定性高于溴代苯醌,异构体在水中的稳定性也有差别. 相似文献
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Disinfectants are commonly applied to control the growth of microorganisms in drinking water distribution systems. However, the effect of disinfection on drinking water microbial community remains poorly understood. The present study investigated the impacts of different disinfectants (chlorine and chloramine) and dosages on biofilm bacterial community in bench-scale pipe section reactors. Illumina MiSeq sequencing illustrated that disinfection strategy could affect both bacterial diversity and community structure of drinking water biofilm. Proteobacteria tended to predominate in chloraminated drinking water biofilms, while Firmicutes in chlorinated and unchlorinated biofilms. The major proteobacterial groups were influenced by both disinfectant type and dosage. In addition, chloramination had a more profound impact on bacterial community than chlorination. 相似文献
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Eight typical drinking water supplies in China were selected in this study. Both source and tap water were used to investigate the
occurrence of chlorinated disinfection byproducts (DBPs), and seasonal variation in the concentrations of trihalomethanes (THMs) of
seven water sources was compared. The results showed that the pollution level for source water in China, as shown by DBP formation
potential, was low. The most encountered DBPs were chloroform, dichloroacetic acid, trichloroacetic acid, and chlorodibromoacetic
acid. The concentration of every THMs and haloacetic acid (HAA) compound was under the limit of standards for drinking water
quality. The highest total THMs concentrations were detected in spring. 相似文献
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正Introduction Natural organic matter(NOM)present in source water has significant impact on water treatment processes and on the quality of drinking water.NOM is a complex mixture of diverse groups of organic compounds,humic and fulvic acids,proteins,peptides,carbohydrates,and heterogeneous materials 相似文献
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饮用水消毒技术发展趋势的文献计量学分析 总被引:1,自引:0,他引:1
消毒过程是饮用水安全保障研究的热点,本文采用文献计量学的方法对2000—2012年间的学术论文和发明专利进行了分析,明确了全球在饮用水消毒领域的研究动态和趋势以及我国存在的主要差距.结果表明全球对该领域研究的关注度持续增加,其研究热点主要集中在消毒技术工艺和消毒副产物两方面,其中氯化、臭氧氧化、氯化消毒副产物是近十余年的关注焦点.美国和瑞士作为本领域研究的主要领先国家分别在文章产出量和研究水平上位列第一,值得注意的是瑞士在本领域的研究偏重于高级氧化技术和新型消毒副产物.我国的发文量仅次于美国而专利申请量仅次于日本,但研究水平远落后于世界领先国家.我国的研究工作主要集中在氯氧化消毒工艺和常规消毒副产物生成与控制,原创性研究有待加强.本研究对明确我国饮用水消毒技术的发展趋势和研究人员选题具有重要意义. 相似文献
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Pyridine, an important chemical raw material, is widely used in industry, for example in textiles,leather, printing, dyeing, etc. In this research, a dielectric barrier discharge(DBD) system was developed to remove pyridine, as a representative type of nitrogen heterocyclic compound in drinking water. First, the influence of the active species inhibitors tertiary butanol alcohol(TBA),HCO_3~-, and CO_3~(2-)on the degradation rate of pyridine was investigated to verify the existence of active species produced by the strong ionization discharge in the system. The intermediate and final products generated in the degradation process of pyridine were confirmed and analyzed through a series of analytical techniques, including liquid chromatography–mass spectrometry(LC–MS), high performance liquid chromatography(HPLC), ion chromatography(IC), total organic carbon(TOC) analysis, ultraviolet(UV) spectroscopy, etc. The results showed that the degradation of pyridine was mainly due to the strong oxidizing power of ozone and hydroxyl radical produced by the DBD system. Several intermediate products including 3-hydroxyl pyridine, fumaric acid, 2, 3-dihydroxypyridine, and oxalic acid were detected. Nitrogen was removed from the pyridine molecule to form nitrate. Through analysis of the degradation mechanism of pyridine, the oxidation pathway was deduced. The study provided a theoretical and experimental basis for the application of DBD strong ionization discharge in treatment of nitrogen heterocyclic compounds in drinking water. 相似文献
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The genotoxicity of drinking water treated with 6 disinfection methods and the effects of disinfection conditions were investigated using the umu-test. The pretreatment procedure of samples for the umu-test was optimized for drinking water analysis. The results of the umu-test were in good correlation with those of the Ames-test. The genotoxicity and production of haloacetic acids (HAAs) were the highest for chlorinated samples. UV + chloramination is the safest disinfection method from the aspects of genotoxicity, HAA production and inactivation effects. For chloramination, the effects of the mass ratio of Cl2 to N of chloramine on genotoxicity were also studied. The changes of genotoxicity were different from those of HAA production, which implied that HAA production cannot represent the genotoxic potential of water. The genotoxicity per chlorine decay of chlorination and chloramination had similar trends, indicating that the reaction of organic matters and chlorine made a great contribution to the genotoxicity. The results of this study are of engineering significance for optimizing the operation of waterworks. 相似文献
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Although disinfection byproducts(DBPs) in drinking water have been suggested as a cancer causing factor, the causative compounds have not yet been clarified. In this study, we used liquid chromatography quadrupole-time-of-flight spectrometry(LC-QTOF MS) to identify the unknown disinfection byproducts(DBPs) in drinking water produced from Taihu Lake source water, which is known as a convergence point for the anthropogenic pollutants discharged from intensive industrial activities in the surroundi... 相似文献