青草沙原水加氯消毒工艺的优化

运用法国威立雅水务的加氯消毒理论和加药量理论计算，结合水厂消毒过程和青草沙原水特点，优化青草河原水加氯工艺，合理加氯加氨。着重探究青草沙原水加氯消毒与饮用水安全，通过折点加氯来运行整个工艺，杀灭病原体，减少有机营养物，以滤后一氯胺和游离氨作为工艺控制参数，限制供水管网中微生物生长，控制加氯和加氨量的最小化，降低药耗，节约成本，改善饮用水口感，保证供水水质安全。     

预加氯工艺对南水北调引江原水的适用性研究

在天津某净水厂进行不同预加氯浓度条件下脉冲澄清和斜管沉淀两套工艺下的南水北调引江原水处理中试实验,分析在生产上采用预加氯工艺的可行性,并进行生产性验证。中试结果表明,引江原水高温高藻期,预加氯1.3～1.8 mg/L,混凝剂总投加量27～35 mg/L时,滤后水浊度、耗氧量、氯消毒副产物指标均满足国标要求。生产性验证实验结果表明,引江原水低温低浊期,混凝剂总投加量均为30 mg/L时,采用预加氯（投加量1.0 mg/L）工艺时出厂水氯消毒副产物远低于国标限值,浊度、耗氧量的去除率与采用预臭氧（投加量1.0 mg/L）工艺相当,能够保证安全优质供水。     

出厂水氯胺消毒的控制与管理

该文介绍了上海市自来水市南公司以青草沙水源和黄浦江水源的水厂制水工艺和氯胺消毒工艺,列出了出厂水及管网水中余氯、氨氮以及消毒副产品的测定数据及消毒效果,分析了氯胺及氨氮在管网中的衰减情况,讨论了pH对氯胺在水中存在形式的影响及氨氮导致管网水中铅及锌的浓度增加。提出了为提高管网水质,在生产过程中需在适当工艺位置补加在线测氨仪及测氯胺仪,并选择合适的C12：NH2-N,严格控制出厂氨氮的量,以抑制氨氧化细菌的营养来源。建议将氨氮、亚硝酸盐纳入管网水控制的日常检测项目。     

青草沙水源全系统加氯对出水三卤甲烷的影响

针对青草沙水源为削减藻类在原水投加次氯酸钠可能造成出水TTHMs升高的风险,调研了相关水厂原水、过程水、出厂水的余氯和三卤甲烷生成情况。调研数据显示:水源预加氯生成的TTHMs占出水TTHMs总量的30%~60%;水厂前加氯生成的TTHMs量占厂内工艺生成TTHMs总量的80%以上,滤后氯胺消毒对TTHMs生成贡献很小。在原水水质稳定的情况下,水源预加氯量、水厂前加氯量、沉后余氯均是控制TTHMs的重要因子。因此,需控制水源预加氯量、尽可能将原水TTHMs控制在0.2以下;水厂需根据水温和工艺条件,通过控制沉淀池出口余氯和前加氯量,将出厂水TTHMs有效控制在国标限值1/2以下。     

不同原水的氯化消毒工艺研究

对上海市两个水源的原消毒工艺进行了化合氯和游离氯两种工艺的实验室和生产性试验，根据消毒副产物的测定数据，认为对黄浦江原水应采用化合氯消毒，而以长江为原水时，可采用游离氯消毒，要改变一次性加氯方式，减少预加氯量，增加滤后水加氯量。     

余氯检测方法分析

当前哈尔滨市供水、医疗废水及生活污水处理过程中采用的都是加氯的方法,利用加氯消毒试剂和水经过一定时间的接触,起以消毒及灭菌的作用。部分氯会被水中可氧化物质消耗掉,没有消耗掉的氯则会以次氯酸、次氯酸盐离子和溶解的单质氯气分子共同组成游离余氯。如果水中含有氨胺类及氨基酸类氮化物时,还会生成一氯胺、二氯胺和三氯胺等化合余氯。但过量的游离余氯会与水中有机物发生一系列的反应,所产生的物质会严重危害人体的健康。     

顺序投加联合消毒剂二氧化氯-氯胺对饮用水中消毒副产物的控制

传统氯消毒工艺因易生成对人体有害的消毒副产物被广泛关注,采用替代氯消毒工艺控制消毒副产物是目前的研究重点。该文以天津市某自来水厂滤后水为试验对象,采用二氧化氯-氯胺顺序投加联合消毒工艺,分析了不同投加量组合对消毒副产物(THMs,HAAs和亚氯酸盐)产量的控制情况。结果表明当二氧化氯投加量为0.10~0.50 mg/L、氯胺投加量为0.50~1.50 mg/L时,消毒副产物的生成量均能得到有效控制,符合相关标准的要求。     

顺序氯化消毒对微污染原水消毒副产物控制研究

针对某市备用微污染水源水,研究了在短时游离氯后转氯胺的顺序氯化消毒工艺下的消毒副产物生成特性,并探究了消毒方式、加氨转化时间、氯胺比和p H对消毒副产物(DBPs)生成量的影响。结果表明,顺序氯化组合工艺能够大大降低消毒过程中目标含碳消毒副产物(C-DBPs)和含氮消毒副产物(N-DBPs)的生成量,优化的加氨转化时间应控制在30 min内,适宜的氯氮质量比在1/5~1/3;组合工艺中产生的C-DBPs和N-DBPs受p H的影响较复杂,由短时游离氯和转氨后氯胺消毒两部分组成,前者DBPs生成量随p H的升高而增加,后者随p H的升高而降低,整体工艺随p H的升高由前10 min自由氯对DBPs生成量的贡献越大。     

氯胺消毒法对自来水中三氯甲烷形成影响的研究

本文对同一原水分别经单氯和氯胺消毒两种工艺制成的自来水中产生的三氯甲烷含量进行了对比，实验表明：当水中含有一定量的氨时，氯消毒所产生的副产物三氯甲烷的含量显著减少，其生成量与氨的投加量呈一定的反比例关系。因此，氯胺消毒法对降低自来水中三氯甲烷含量是有效的。     

水厂投加次氯酸钠控制系统设计与应用

利用施耐德140系列PLC设计水厂自动加次氯酸钠控制系统,使出厂水余氯含量控制在国标范围内。前加氯、主加氯采用与水流量成比例投加,然后根据余氯值和总氯采样值与设定值构成串级控制系统最终输出控制计量泵频率冲程。同时利用Unity编程平台进行程序设计,实现了对次氯酸钠系统的自动控制,降低了人工劳动强度。     

消毒副产物N-亚硝基二甲胺的生成规律研究

为了研究氨氮和有机氮化合物共存体系加氯消毒条件下N-亚硝基二甲胺（NDMA）的生成规律,采用50mg/L氨氮加氯消毒再与30mg/L 的二甲胺（DMA）反应,首先研究了反应时间、氯胺浓度、pH值、氯氮比（自由氯与氨氮的质量比）对NDMA生成量的影响;然后在此基础上选取废水体系中具有代表性的3种有机氮化合物尿素、甘氨酸、苯丙氨酸,重点考察了这3种有机氮化合物对氯胺以及对NDMA生成情况的影响。结果表明：pH值和氯氮比对NDMA生成量影响最大;氨氮溶液中加入有机氮化合物后加氯消毒,会使生成一氯胺浓度的峰值点向氯氮比增大的方向移动,同时会降低同一氯氮比下NDMA的生成量。     

Balancing disinfection efficiency and THM formation during chlorination: Theoretical considerations

A mathematical model has been developed to predict disinfection efficiency and trihalomethane (THM) formation during water chlorination. The model incorporates chlorine dose, total organic carbon (TOC) concentration, contact time, and geometric configuration of the chlorination chamber. Results indicate that the disinfection efficiency can be better controlled by modifying the geometric configuration of the chlorine contactor. In contrast, geometric configuration plays an insignificant role in controlling THM formation. The application of chlorine at about 1.0 mg/L appears to be the most economic and logical dose for the control of THM formation and the disinfection efficiency of the Liu-Du water treatment plant under the operational conditions of conventional chlorination practices.     

紫外线与氯联合消毒在饮用水处理中的应用研究

介绍了紫外线与氯联合消毒工艺对北江水域常规处理后的滤后水进行消毒的工艺,通过研究紫外线消毒的持续时间,紫外线与氯联合消毒工艺的副产物及紫外线对氯投加量的影响等,探讨该消毒工艺在大中型给水厂中的实用性。     

超滤膜技术组合工艺对饮用水氯消毒的生物稳定性试验

以某水库微污染水源水为试验水样,比较了以超滤为核心的不同组合工艺的净水效果,考察了各组合工艺出水氯消毒对异养菌的灭活效果、持续消毒能力,研究了余氯的衰减、消毒副产物的生成以及对水质生物稳定的影响,从生物安全性和化学安全性两个方面对不同超滤组合工艺出水氯消毒安全性进行综合评价。结果表明,混凝沉淀-粉末活性炭-超滤组合工艺具有最佳的净水效果:该工艺能100%的去除水中的细菌总数、大肠杆菌;持续消毒能力强,72 h后水中余氯量为0.5 mg/L,对细菌总数、大肠杆菌的去除率仍为100%,且HPC小于100 CFU/mL,符合生活饮用水卫生标准;消毒副产物的生成量控制在10μg/L以下;出水AOC含量低于100μgac-C/L,符合氯化消毒生物稳定性的要求。     

饮用水氯化消毒工艺现存问题及改进措施

针对氯化消毒工艺现存的主要问题,分别从加氯点的设置、加氯量、加氯混合效果、加氯系统控制手段四个方面提出了改进措施,以达到提高消毒效率、减少氯消毒副产物、控制生产成本的目的。     

Studies on chlorination of greywater

In view of the growing implementation of systems for treated greywater reuse, and as chlorination is an eventual step of the treatment to assure disinfection, a study of variables affecting the residual chlorine decay in greywater are reported in this paper. The investigation was carried out at laboratory scale with chlorinated samples, and the residual chlorine was measured spectrophotometrically with o-tolidine. To discuss the effects of these variables, decay curves were compared, or alternatively, fitted to a parallel first order decay model. Studied variables were: pH, surfactants, coliform bacteria, ammonia concentration, coagulant agents, potassium permanganate concentration, filtration and storage time. The obtained results showed that residual chlorine can be stabilized by: ammonia, by preoxidation with potassium permanganate or by treatment with coagulanting-flocculanting agents. Surfactants and bacteria were shown to favoured chlorine consumption. Results from this study can be useful to define the working conditions of full-scale systems where the reduction of chlorination dose is a matter of great interest to minimize the environmental impact of the systems.     

折点加氯去除水中氨氮

通过调节投氯量,改变水中氯和氨的比例,利用氯的强氧化性,将水中氨氮氧化成氮气去除。本文以实验室试验数据为基础,分析投氯量与各水质主要指标之间的关系,并在实际生产中验证其规律。结果表明,折点加氯确实可以有效去除水中氨氮。     

氯消毒副产物及其影响因素的研究概况

氯消毒因其效果可靠、操作简便、价格便宜等优点而成为污水消毒中广泛采用的方法,但氯消毒过程中产生的有毒副产物可能带来的化学安全问题则成为越来越受关注的焦点.本文主要是研究氯消毒副产物的生成及其影响因素,为污水氯消毒实践中消毒条件的选择、水质控制及相关水质安全标准的制定提供依据.     

Comparison of electrochemical method with ozonation, chlorination and monochloramination in drinking water disinfection

Electrochemical process in chloride-free electrolytes was proved to be powerful in disinfection due to the strong oxidants produced in the electrolysis and no formation of disinfection byproducts (DBPs). In this study, disinfection experiments were conducted by electrochemical treatment compared with ordinary and advanced methods (ozonation, chlorination and monochloramination), with Escherichia coli (E. coli) K-12, Staphylococcus aureus (S. aureus) A106, Bacillus subtilis (BST) and an isolated Bacillus as the representative microorganisms. Firstly, factor tests were performed on E. coli to obtain the optimal conditions of the four disinfection procedures. At their respective optimal condition, CT (concentration of disinfectant × contact time) value of a 4-log E. coli inactivation was 33.5, 1440, 1575, 1674 mg min L⁻¹ for electrochemical process, ozonation, chlorination and monochloramination, respectively. It was demonstrated that the disinfection availability was in the following order: electrochemical process > ozonation > chlorination > monochloramination, which could be attributed to the hydroxyl radical generated in the electrolysis, with strong oxidizing ability and non-selectivity compared with the other three disinfectants. Moreover, the disinfection efficacy of the four disinfection procedures was compared for four different bacteria. It was found that the disinfection efficacy was similar for the selected four bacteria in electrochemical process, while in the other three treatments inactivation of the two Bacillus was much slower than E. coli and S. aureus. As a result, the non-selectivity of electrochemical disinfection with BDD anode to different kinds of microorganisms was further proved, which was primarily controlled by the hydroxyl radicals existed in the free state. For each bacterium, the order of disinfection availability of the four processes was consistent. Finally, scanning electron microscopy (SEM) was implemented to observe the cell morphology. It was shown that cell surface damage was more obvious in electrochemical system with strong oxidants compared with that after ozone treatment, while the integrity of cells were not affected in weak oxidizing chlorine and monochloramine.