臭氧氧化工艺溴酸盐控制中试研究

通过1m3/h的中试装置研究了臭氧氧化工艺处理引黄水库水时溴酸盐控制技术。结果表明,在臭氧投加量为1.5mg/L时,臭氧氧化后溴酸盐产生量为0.006mg/L,活性炭过滤出水溴酸盐为0.002mg/L;在相同臭氧投加量条件下,降低原水pH、投加高锰酸钾和过氧化氢后溴酸盐生成量分别减少了50%、33%和100%,活性炭后出水中均未检出溴酸盐,同时提高了有机物去除率。     

腐殖酸对溴酸盐生成与控制的影响研究

含溴水源水在应用臭氧氧化过程中,存在致癌物溴酸盐生成或超标(10μg/L)的风险,过氧化氢投加能有效控制溴酸盐,然而在以往的研究中,不同的水源水应用过氧化氢控制溴酸盐的效果存在很大差异。以我国东部某水源水作为研究对象,考察水源水质因素中腐殖酸类有机物对溴酸盐生成与控制的影响。研究发现该水源臭氧氧化过程中溴酸盐生成量达到17.52μg/L,水中腐殖酸浓度(以DOC计)的增加使得体系内溴酸盐的生成量有所降低,当DOC增加2.0mg/L时,溴酸盐生成量降低到10.11μg/L。过氧化氢控制溴酸盐过程中,随着H_2O_2/O_3(g/g)的增加,溴酸盐生成量逐渐降低,当H_2O_2/O_3(g/g)为1.0时,溴酸盐被控制在标准以内,为6.32μg/L。当原水中腐殖酸含量增加时,溴酸盐生成量随H_2O_2/O_3(g/g)的增加而逐渐降低,且导致所需投加过氧化氢量减少,当DOC增加1.0 mg/L时,H_2O_2/O_3(g/g)为0.1,即能将溴酸盐控制在9.52μg/L,DOC增加2.0mg/L时,H_2O_2/O_3(g/g)为0.1,溴酸盐控制在7.92μg/L。     

投加H_2O_2控制溴酸盐技术在水厂深度处理工艺中的应用研究

对郑州某水厂深度处理改造过程中溴酸盐控制技术开展了为期一年的中试研究。结果表明在当地水源水质条件下,臭氧化过程中存在溴酸盐生成超标的风险;投加过氧化氢与臭氧联用,投加摩尔比1.5∶1,可有效控制较高臭氧投加量条件下的溴酸盐生成风险;而工艺中的剩余过氧化氢可通过后续的活性炭工艺完全消除。依据试验结果,在水厂深度处理改造工程设计中增加了相关过氧化氢投加装置及应用参数。     

东太湖水源臭氧-活性炭工艺中溴酸盐生成及其影响因素

东太湖水中溴离子含量较高,采用臭氧-活性炭工艺很可能会导致出厂水中溴酸盐超标。研究了以东太湖为水源的吴江第二水厂各处理工艺中溴酸盐的生成情况以及影响因素,结果表明,原水中的溴离子在臭氧氧化过程中主要产物为溴酸盐,分析了影响水厂溴酸盐生成的主要因素为水温、臭氧浓度和有机物含量。利用小试进一步研究了这些因素对臭氧氧化原水过程中溴酸盐生成的影响规律。研究结果表明,随着臭氧浓度的增加,溴酸盐生成量逐渐增多,在臭氧浓度达到2.2mg/L时溴酸盐生成量接近限值10μg/L,在相同的臭氧浓度下,较短的接触时间、高温以及高氨氮会减少溴酸盐的生成。     

河北应急水源的预臭氧化工艺研究

南水北调的应急工程是从河北四水库调水进京,四水库水源水质与密云水库水质相差较大.为了保证河北水进京后水厂工艺运行的稳定性,根据水厂现行工艺(混凝-沉淀-煤砂过滤-活性炭过滤)增加预臭氧在河北黄壁庄水库进行适应性研究.试验结果表明:在投加臭氧1.5～2.6 mg/L后炭出水基本无味;试验条件为:臭氧浓度0.4 mg/L,接触时间8 min时,预臭氧能够将剑水蚤杀死去除;预臭氧后系统对有机物去除效果较好,且沉后藻类去除率达到80%以上,煤滤池出水藻类低于2万个/L;中试系统煤滤池出水和炭滤池出水溴酸盐浓度均小于5 μg/L,因此臭氧氧化后不存在溴酸盐副产物超标的风险.同时,建议在河北水进京前测定水中MIB浓度,适时调整臭氧投加量,在有必要的情况下考虑增加粉末活性炭预吸附.     

三级催化臭氧氧化-生物活性炭技术处理污染水源水中试研究

以三级催化臭氧氧化-生物活性炭技术为基础,针对受污染水源水的深度处理进行了为期9个月中试研究。中试规模为120m3/d,经历了夏季到冬季过程中水温、水质的变化。研究结果表明,出水中耗氧量、NH3-N、浊度、色度、铁和锰都能达到《生活饮用水卫生标准》(GB5749-2006),THMsFP减少18%。催化剂的投加能有效降低工艺出水中溴酸盐的含量,溴酸盐的含量较不投加催化剂降低了77%,臭氧投加量对锰的去除率影响不大。     

饮用水中卤代苯醌类消毒副产物生成影响研究

针对近年发现的可能导致膀胱癌的新型消毒副产物(DBPs)卤代苯醌(HBQs),研究了不同地区管网末端水中卤代苯醌的存在情况,以及不同前体物、pH、氯投加量及溴离子浓度对卤代苯醌生成的影响.结果表明,多数管网末端出水中可检出2,6-二氯苯醌(2,6-DCBQ),浓度范围为6.28～10.75 ng/L,2,6-二溴苯醌(2,6-DBBQ)均未检出.腐殖酸、富里酸及酚类化合物氯化过程中能够生成HBQs.以双酚A(BPA)为前体物时,2,6-DCBQ的生成量随pH的提高先升高再降低,pH为6,反应时间为4 h时2,6-DCBQ的生成量最高为393.30μg/L.2,6-DCBQ的生成量随氯的投加量增加而增加,投加量超过0.50 mmol/L时,2,6-DCBQ的生成量随投加量的增加而减小.提高溴离子浓度后2,6-DBBQ的生成量逐渐升高,2,6-DCBQ的生成量逐渐降低,溴离子浓度为1000μg/L时,2,6-DBBQ的生成量最大,为131.67μg/L.     

MnO_x-GAC催化臭氧化印染废水的实验研究

研究MnO_x-GAC高级氧化方法处理难降解印染废水CODcr、UV254、色度的效果,并考察催化剂投加量、不同初始pH值、不同初始污染物浓度、催化剂重复使用次数对印染废水处理效果的影响。实验结果表明:催化剂的最佳投加量为180g,在弱酸性及中性p H值范围内,MnO_x-GAC催化臭氧化对印染废水CODcr去除效果明显,废水的初始污染物浓度越低,在越短的时间内即可达到较好的处理效果,催化剂使用4次后比单独臭氧化对CODcr去除率提高约27%。     

污水再生处理雾化曝气臭氧氧化系统运行费用分析

雾化曝气臭氧氧化是利用近年来倍受关注的微米气泡将臭氧溶入水中的一项新技术。系统掌握雾化曝气臭氧氧化系统运行费用及其影响因素,对降低其运行成本具有重要意义。影响雾化曝气臭氧氧化系统工程运行费用的主要因素有臭氧投加量、臭氧气体浓度、气液比及循环泵过流水量等工艺参数,其中臭氧投加量和臭氧气体浓度的影响最大。在保证处理效果的前提下,减少臭氧投加量、提高臭氧气体浓度及加大气液比,是有效降低微米气泡发生设备运行费用的关键。研究结果表明,在其他条件相同的情况下,雾化曝气臭氧氧化系统的臭氧投加量需低于微孔曝气臭氧氧化系统的臭氧投加量30%～40%,其运行费用才有优势。     

压力强化混凝沉淀过滤除藻工艺中藻毒素去除研究

为了探究压力强化混凝沉淀过滤除藻工艺中藻毒素的去除效果,试验对比研究了预加压和预氧化后的含藻水,经混凝沉淀、粉末活性炭吸附后的藻毒素去除效果,考察了不同粉末活性炭投加点及投加量对藻毒素去除效果的影响。结果表明,含藻水加压后混凝沉淀,藻类和浊度物质去除效果最优,蓝藻去除率达到96.2%,浊度降至0.49NTU。含藻水在加压和高锰酸钾预氧化后,水中藻毒素浓度未增加,而次氯酸钠预氧化后水中藻毒素浓度最大增幅为215.78%;对于加压水样,在混凝剂投加前30min或投加后7min投加粉末活性炭效果较好,粉末活性炭投加量为5~20 mg/L时,沉淀水藻毒素平均去除率分别达54.13%和53.57%,而与混凝剂同时投加则效果不佳。对次氯酸钠预氧化的水样,粉末活性炭与混凝剂同时投加时效果最好,沉淀水藻毒素平均去除率15.84%。     

活性炭去除饮用水中溴酸盐的研究进展

臭氧氧化过程中产生的溴酸盐的问题已经成为目前臭氧大规模应用于饮用水中的最大制约因素。活性炭去除法是国内外最常用的去除溴酸盐的方法,且由于活性炭常作为臭氧氧化工艺必备的联用工艺,容易实现生产应用,且不需要增加额外的投资,引起了研究者的极大关注。本文全面阐述了关于活性炭／生物活性炭对溴酸盐的去除效能、去除机理及影响因素的研究进展。针对活性炭去除饮用水中溴酸盐的研究现状,提出了今后研究的主要方向和亟需解决的问题。     

The basics of oxidants in water treatment. Part B: ozone reactions.

The oxidation of organic and inorganic compounds during ozonation can occur via ozone or OH radicals or a combination thereof. Ozone is an electrophile with a high selectivity. The reactions of ozone with inorganic compounds are typically fast and occur by an oxygen atom transfer reaction. Organic micropollutants are oxidised with ozone selectively. Ozone reacts mainly with double bonds, activated aromatic systems and non-protonated amines. The kinetics of direct ozone reactions depend strongly on the speciation (acid-base, metal complexation). The reaction of OH radicals with the majority of inorganic and organic compounds is nearly diffusion-controlled. The degree of oxidation by ozone and OH radicals is given by the corresponding kinetics and the ratio of the concentration of the two oxidants. Product formation from the ozonation of organic micropollutants has only been established for a few compounds. Numerous organic and inorganic ozonation disinfection/oxidation byproducts have been identified. The byproduct of main concern is bromate, which is formed in bromide-containing waters. A low drinking water standard of 10 microgL(-1) has been set for bromate. In certain cases (bromide > approximately 50 microgL(-1)), it may be necessary to use control measures to lower bromate formation (lowering of pH, ammonia addition, chlorination-ammonia process).     

AOPs with ozone and UV radiation in drinking water: contaminants removal and effects on disinfection byproducts formation.

In this study, the advanced oxidation with ozone and UV radiation (with two low pressure UV lamps, at 254 and 185 nm wavelength) were experimented on a surface water in order to study the removal of two odorous compounds (geosmin and 2-methylisoborneol) and a pesticide (metolachlor), the influence on organic compounds (UV absorbance and THM precursors) and bromate formation. Different batch tests were performed with ozone concentration up to 10 mg/L, UV dose up to 14,000 J/m2 and a maximum contact time of 10 minutes. The main results show that metolachlor can be efficiently removed with ozone alone while for geosmin and MIB a complete removal can be obtained with the advanced oxidation of ozone (with concentration of 1.5-3 mg/L and contact time of 2-3 minutes) with UV radiation (with doses of 5,000-6,000 J/m2). As concerns the influence on the organic precursors, all the experimented processes show a medium removal of about 20-40% for UV absorbance and 15-30% for THMFP (trihalomethanes formation potential). As concerns bromate formation, the advanced oxidation of ozone/UV 254 nm shows a bromate formation that is about 40% lower with respect to conventional oxidation with ozone.     

赣北地区农村饮用水水源水质概况及水源地保护

通过调查南昌、九江、上饶3个地区的农村饮水安全工程的水源地,结果显示赣北地区农村饮用水水源水质良好,达到国家Ⅲ类水标准,但也存在地表水中总磷、细菌总数超标,地下水中Mn含量超标的情况.主要污染源来自农业面源污染、工矿企业生产活动及废水排放污染等.赣北地区农村饮用水水源地保护工作有待加强,需通过技术和管理两个层面来保护农村饮用水水源地.     

小型农村饮水安全工程消毒设备选用初探

小型农村饮水消毒设施的选用,对小型农村饮水安全工程消毒设施的建后使用和管理至关重要,通过比较氯化消毒、二氧化氯消毒、臭氧消毒和紫外线消毒的消毒能力、消毒剂性质和消毒设备的成本,提出了桂林市雁山区小型农村饮水工程应采用紫外线消毒措施.     

基于ArcGIS的水源地水质健康风险研究

针对农村饮水安全中水质不安全的问题,实地采集了名山县 81 个农村饮水水源地的水样,应用美国科学院国家研究委员会 (U.S. National Research Council of National Academy of Science) 推荐的健康风险模型计算并分析了本区农村水源地饮水水质的致癌风险（R）和非致癌风险 (危害指数 ,HI) ;利用 ArcGIS 的空间分析功能,选择合理的插值方法,对评价结果数据进行了分析,得出研究区水质风险的空间分布图,对该县农村饮水水质进行了致癌物及非致癌物的健康风险单因子和组合因子的综合评价;指出：水源地中主要的致癌物是砷、铬（6+）和铅;非致癌物的健康风险主要来源于砷、氟化物、硝酸盐、铁。研究结论揭示了研究区水源地水质健康风险控制指标,为水源地的治理提供了科学的参考建议。     

维多利亚艳蓝BO光度法测定水中痕量溴酸盐

建立一种高灵敏测定水中痕量溴酸盐的新方法.酸性水溶液中,过量的碘离子被溶液中溴酸盐氧化生成Ⅰ3-.磷酸-磷酸二氢钠缓冲溶液中,乳化剂OP共存下,Ⅰ3-离子与维多利亚艳蓝BO(VPB BO)反应生成艳蓝色离子缔合物,分光光度法测定水溶液中痕量溴酸盐.在580 nm波长处,缔合物表观摩尔吸光系数可高达105数量级.应用该方法测定饮用水中痕量溴酸盐并进行回收实验,测定结果令人满意.VPB BO分光光度法测定水中痕量溴酸盐具有灵敏度高、操作简便、快速、准确等优点.     

江汉平原农村饮用水净化工艺研究

针对江汉平原农村地表水污染情况和农村水生疾病的状况,设计了农村饮用水的净化方案与工艺,以满足农村居民的基本饮水需求。工艺设计兼顾了集成式装置对结构紧凑的要求和净化功能;预处理选用臭氧预氧化和混凝沉降进行,常规处理选用可靠的石英砂过滤,深度处理选用紫外线杀菌和膜分离。在水处理工艺的基础上,设计了一套集混合、絮凝、沉降于一体的旋流强化混凝设备。该水处理系统采用模块化组合,结构紧凑,安装、使用方便,为农村饮用水的净化提供了新的方法。     

The effect of oxidants on 2-MIB concentration with the presence of cyanobacteria.

In this study, the effect of three oxidants, sodium hypochlorite, potassium permanganate, and ozone, were tested for the removal of 2-MIB with presence of cyanobacteria. Algae in water samples from the source water of Feng-Shen waterworks (FSW), Taiwan were cultivated at 30 degrees C with continuous light at an intensity between 2,500 and 3,400 lux. During the cultivating process, water samples were analyzed for nutrients, light absorbance at 665 nm (A665), and 2-MIB concentration. The 2-MIB concentrations within the incubated samples increased to as high as 1,000 ng/L to 2,000 ng/L, although no extra nutrients were added to the raw water. After 2 to 3 days incubation, the intracellular 2-MIB concentration was as high as 70% of the total 2-MIB in the samples. The algae that developed were mainly cyanobateria, and more than 90% belonged to the Genus Oscillatorias. An almost 100% removal of both 2-MIB and geosmin in the raw water was observed after ozonation for 10 minutes at a dosing rate of 0.91 mg/l-min. Chlorine and permanganate were much less effective, both removing only about 11% of the 2-MIB within 60 minutes at oxidant concentration of 10 mg/l. Oxidation of the cultivated samples showed that chlorine and permanganate may damage algae cells causing them to release intracellular 2-MIB. During the 60 minutes of reaction time, the total 2-MIB concentrations (intracellular plus dissolved) varied by no more than 10%, however, the ratios between dissolved and total 2-MIB concentrations increased. Two effects of ozonation on the 2-MIB concentration in the cultivated samples were observed when the algae were young, namely 2-MIB release from damaged cells and 2-MIB oxidization. The rates of 2-MIB release and 2-MIB destruction were similar. However, old algae cells were more easily damaged. As a result, intracellular 2-MIB was released faster, and the soluble 2-MIB was destroyed more quickly by ozonation.