回用水紫外线消毒

在污水的深度处理工艺中,紫外线消毒具有很多优点,如不向水中投加化学剂,停留时间短,运行管理安全等.本文在研究紫外线静态试验中,紫外线投量与细菌存活率之间的关系,可作为紫外线消毒器的设计依据.基于静态实验的结果,在规模为2.5m~3/h的消毒器中进行了动态实验.实验结果表明,消毒后出水中细菌总数<100个/mL,满足回用要求.     

二沉池出水的电化学消毒试验研究

对德国威斯巴登城市污水处理厂和上海石化股份公司水质净化厂二沉池出水分别进行了电化学消毒试验。试验结果表明，用电化学方法对威斯巴登城市污水处理厂和上海石化股份公司水质净化厂二沉池出水进行消毒是可行的，消毒效果好，耗电少，杀菌率随电流、处理时间的增加而提高。     

负载型Ti02／活性炭光催化灭活大肠杆菌（E．coli）的研究

以大肠杆菌（Escherichia coli JM 109）为研究对象，通过细菌的灭活实验研究负载型TiO2／活性炭（TiO2／AC）的灭菌性能，并利用XRD、BET和SEM对材料的晶型、晶粒尺寸、比表面积和吸附在材料上的细菌分布形态及数量进行分析。结果表明：吸附在TiO：／AC上的大肠杆菌数比吸附在活性炭和TiO2都多。TiO2／AC对E．coli光催化灭活率比TiO2粉末和P25高，制备材料的热处理温度500℃和光催化反应中光强40W都分别使TiO2／AC的光催化活性达到最大，在光催化灭活E．coli过程中，KH2PO4使催化剂活性降低程度比NaHCO3大，而两者使TiO2／AC催化活性降低程度比Ti02小，但NaHCO3对催化活性的影响是可逆的。     

PERFORMANCE OF A NEW POLYMERIC WATER DISINFECTANT1

ABSTRACT: A new insoluble N-halamine polymeric disinfectant material has been tested in a water filter application to determine (1) its tendencies to leach undesirable decomposition products, (2) its range of potential applicability, and (3) its regenerability. In flowing water tests, poly-1,3-dichloro-5-methyl-5-(4‘-vinylphenyl)hydantoin (Poly-I) leached only small amounts of total organic carbon, free and total chlorine, anions, and volatile organics such as trihalomethanes. Furthermore, Poly-I provided bactericidal efficacy over the pH range 4.5 to 9.5 and at temperatures as high as 37°C. Poly-I is deactivated by reducing agents such as sodium thiosulfate and by ethanol; following deactivation, it can be regenerated by exposure to flowing aqueous free chlorine. Poly-I appears suitable for use as a biocidal filter for small potable and recreational waters, for it is effective over a wide pH and temperature range and is readily regenerable. It would not be useful, however, for disinfection of large bodies of water such as in city treatment plants because of its cost and the large amount of the material that would be necessary.     

Occurrence and formation of disinfection by-products in the swimming pool environment: A critical review

Disinfection of water for human use is essential to protect against microbial disease; however, disinfection also leads to formation of disinfection by-products (DBPs), some of which are of health concern. From a chemical perspective, swimming pools are a complex matrix, with continual addition of a wide range of natural and anthropogenic chemicals via filling waters, disinfectant addition, pharmaceuticals and personal care products and human body excretions. Natural organic matter, trace amounts of DBPs and chlorine or chloramines may be introduced by the filling water, which is commonly disinfected distributed drinking water. Chlorine and/or bromine is continually introduced via the addition of chemical disinfectants to the pool. Human body excretions (sweat, urine and saliva) and pharmaceuticals and personal care products (sunscreens, cosmetics, hair products and lotions) are introduced by swimmers. High addition of disinfectant leads to a high formation of DBPs from reaction of some of the chemicals with the disinfectant. Swimming pool air is also of concern as volatile DBPs partition into the air above the pool. The presence of bromine leads to the formation of a wide range of bromo- and bromo/chloro-DBPs, and Br-DBPs are more toxic than their chlorinated analogues. This is particularly important for seawater-filled pools or pools using a bromine-based disinfectant. This review summarises chemical contaminants and DBPs in swimming pool waters, as well as in the air above pools. Factors that have been found to affect DBP formation in pools are discussed. The impact of the swimming pool environment on human health is reviewed.     

改性高岭土对水源水的混凝消毒作用的研究

采用天然高岭土为原料 ,加入一定量的 Al2 O3、Si O2 和 Fe2 O3,经与 Na2 CO3、KCl O3混合 ,高温 (75 0～ 85 0℃ )固相反应约 3h后制得改性高岭土。本文研究了改性高岭土的不同 Al/ Si摩尔比、p H值和投加量对水源水的混凝絮凝除浊和杀菌效果的影响。结果表明 :改性高岭土在 p H值在 6 .5～ 8.5 ,对水源水的除浊消毒效果较好 ,Al/ Si摩尔比为 5 .0(Al∶ 10 .5 %、Si∶ 2 .1%、Fe∶ 3.8% ) ,剂量 2 0 0 ppm时 ,净化水的浊度 <2 .5 NTU,细菌菌落数 2 3个 / ml,总大肠菌群 <3个 / L ,均达到国家饮用水标准。 p H为 10 .5以上几乎无除浊效果     

黄河原水中消毒副产物前体物的组成特征及其化学预氧化处理效果对比

以取自河南省郑州市石佛原水厂的黄河原水为研究对象,系统研究了原水中消毒副产物(DBPs)前体物的组成规律,对比分析了3种预氧化剂(高锰酸钾、自由氯和二氧化氯)对原水中DBPs生成潜能的消减规律.试验结果表明:原水中DBPs的前体物均以小分子有机物和疏水性组分(52.51%)为主;分子量小于1 k Da有机物组分是生成含氮消毒副产物(N-DBPs)和三卤甲烷(THMs)的主要前体物;疏水性有机物是生成THMs的主要前体物,亲水性有机物是生成N-DBPs的主要前体物.经Cl2预氧化后,直接生成的DBPs随着自由氯投加量的增加而增加,Cl O2和KMn O4预氧化直接增加DBPs产生量.经3种预氧化剂氧化后,原水中三卤甲烷生成潜能(THMFP)均呈现一定的下降,其降低量依次为Cl O2Cl2KMn O4;然而3种预氧化剂都不能有效的减少含氮消毒副产物生成潜能(N-DBPFP),Cl O2预氧化和Cl2预氧化可增加N-DBPs生成潜能,尤其在较高投加量下,Cl2预氧化将大大增加N-DBPs生成潜能.为有效消减总DBPs生成潜能,水厂可优先采用KMn O4或Cl O2作为预氧化剂处理引黄水库或沉砂池水.     

饮用水消毒中茶多酚抑菌机理的研究进展

饮用水消毒关系着人类的身体健康,茶多酚作为绿色消毒剂具有良好的消毒作用及消毒持续性,无毒副作用。对茶多酚的抑菌机理进行系统的综述,介绍了茶多酚对菌体正常生理形态的改变、对细胞壁膜的破坏、对蛋白质合成和表达的阻碍以及对遗传物质的作用,并阐述了酚羟基与金属离子、蛋白质的络合作用,以及酯官能团、聚合度对儿茶素抑菌效能的影响,为茶多酚在饮用水消毒中的应用提供理论基础。     

Advances in photocatalytic disinfection of bacteria: Development of photocatalysts and mechanisms

Photocatalysis has attracted worldwide attention due to its potential in solar energy conversion. As a “green” advanced oxidation technology, it has been extensively used for water disinfection and wastewater treatment. This article provides a review of the recent progress in solar energy-induced photocatalytic disinfection of bacteria, focusing on the development of highly efficient photocatalysts and their underlying mechanisms in bacterial inactivation. The photocatalysts are classified into TiO₂-based and non-TiO₂-based systems, as TiO₂ is the most investigated photocatalyst. The synthesis methods, modification strategies, bacterial disinfection activities and mechanisms of different types of photocatalysts are reviewed in detail. Emphasis is given to the modified TiO₂, including noble metal deposition, non-metal doping, dye sensitization and composite TiO₂, along with typical non-TiO₂-based photocatalysts for bacterial disinfection, including metal oxides, sulfides, bismuth metallates, graphene-based photocatalysts, carbon nitride-based photocatalysts and natural photocatalysts. A simple and versatile methodology by using a partition system combined with scavenging study is introduced to study the photocatalytic disinfection mechanisms in different photocatalytic systems. This review summarizes the current state of the work on photocatalytic disinfection of bacteria, and is expected to offer useful insights for the future development in the field.     

不同再生水消毒方式对斑马鱼胚胎毒性的影响及其危害分级

以斑马鱼胚胎毒性测试研究海南某污水处理厂出水经氯胺、二氧化氯、次氯酸钠、臭氧和紫外几种消毒处理后对斑马鱼胚胎的毒性。利用胚胎毒性和层次分析法构建危害分级方法及其指标体系,评价消毒危害。研究结果表明:消毒处理前的二沉池出水未产生胚胎发育毒性效应,但经次氯酸钠、氯胺、臭氧、二氧化氯对再生水消毒处理可使斑马鱼胚胎出现卵黄囊异常、心跳减缓、色素沉积减少、孵出延缓和卷尾等毒理反应;不同消毒方式处理的再生水可致斑马鱼胚胎死亡率增加,胚胎毒性依次为:二氧化氯紫外紫外+次氯酸钠=二沉池出水(不消毒)氯胺=紫外+氯胺臭氧次氯酸钠;不同消毒方式的危害分级为:二氧化氯和紫外消毒构成轻微危害,危害等级为I级,紫外+次氯酸钠、紫外+氯胺、氯胺消毒构成中度危害,危害等级为II级,次氯酸钠危害较强,其危害等级为III级;化学消毒剂与紫外线组合消毒可降低再生水消毒的危害。