臭氧预氧化对石化污水厂二级出水水质的作用

研究了臭氧预氧化对石化企业综合污水处理厂二级出水水质的改善作用,采用分子量分级、气相色谱质谱联用仪、三维荧光扫描等手段对臭氧预氧化前后水质进行了系统分析,并对预处理前后的二级出水采用曝气生物滤池进行了对比处理研究。结果表明,在二级出水平均COD为77.8 mg·L^-1,臭氧投量为10 mg·L^-1,接触时间为4 min的条件下,臭氧预氧化对COD的平均去除率为11.4%,对UV₂₅₄的平均去除率为23.9%。臭氧预氧化能够去除水中含不饱和键以及溶解性微生物产物和腐殖酸类等难降解有机物,改变了废水中有机物的分子结构,使水中分子量小于1×10³的有机物比例从53%提高至67%。预氧化后废水经BAF处理,其COD去除量较二级出水直接经BAF处理提高了14.9%。     

镇江市饮用水有机物分子量分布特性的研究

研究分析了镇江市原水、净水工艺和管网水中有机物分子量分布的变化特性.试验结果表明：原水水质较好,溶解性有机物含量维持在1.4～2.8mg/L之间,小分子有机物占溶解性有机物的主要部分;与常规处理相比,臭氧活性炭深度处理能有效提高DOC和UV254的去除效果;各个处理流程对大于1000分子量区间的有机物去除效果较好;氯和臭氧氧化能使有机物由高分子量区间向低分子量区间推移.     

臭氧联合混凝去除长江源水中有机污染物的小试研究

以长江重庆段水质为研究对象,考察臭氧对混凝去除水中有机污染物的影响。结果表明,臭氧预氧化后,TOC、UV254的去除率分别为2.5%、11.0%,说明臭氧可以部分彻底氧化去除水中有机物,预氧化后有机物的结构改变比较明显;相比于单独混凝,臭氧联合混凝使TOC和UV254的去除率分别提高了4.9～5.3和12.1～14.2个百分点,臭氧预氧化可以强化混凝对TOC和UV254的去除;臭氧预氧后各个分子段有机物的分布改变比较明显,相对分子质量大于3×103的有机物明显减少,相对分子质量小于3×103的有机物明显增加。相比于单独混凝,臭氧联合混凝主要提高了相对分子质量大于3×103的有机物去除率,降低了相对分子质量小于3×103有机物的去除率。     

饮用水预氧化技术及处理性评价

论文针对天津饮水水源特点，采用预氧化处理技术，研究了高锰酸钾和臭氧预氧化效果以及对后续气浮、过滤等常规处理效果的影响，实验结果表明预氧化能提高后续处理工艺出水水质，降低出水浊度，提高出水水质保障率。预氧化的主要功能在于有效改变有机物的性质和结构，将复杂的芳香类有机物氧化分解为简单的含氧链状类有机物，使有机物开环、断链，     

造纸废水臭氧-曝气生物滤池深度处理技术研究

研究了臭氧-曝气生物滤池工艺对造纸废水二级生化出水的深度处理.结果表明,臭氧预氧化能将难降解的大分子有机物分解成小分子有机物,废水的可生化性得到了显著提高,B/C由0.21提高到0.45.臭氧-曝气生物滤池联合工艺对各种污染物都有很好的去除效果,COD、浊度主要是通过臭氧单元和BAF单元的共同作用去除,氨氮的去除主要是通过BAF单元的生物硝化作用,而UV254、色度的降解则是臭氧起主导作用.经深度处理后,出水可达到新颁布的制浆造纸工业水污染物排放标准.     

某水厂臭氧消毒工艺介绍及设备日常维护经验总结

针对长江微污染原水,臭氧-生物活性炭深度处理工艺较为适宜,能够有效去除饮用水水源中的各种有机污染物,使处理水水质明显提高。臭氧在臭氧+生物活性炭深度处理工艺中,主要起到两大作用:一是将难降解有机物氧化为可生物降解有机物;二是将大分子有机物分解为小分子有机物。以某水厂为例,目前该水厂臭氧系统由原料气储存、臭氧制备、臭氧投加及尾气破坏组成,已投产将近10年,就该厂臭氧系统工艺介绍及设备日常维护做经验总结,为净水厂深度处理改造中臭氧系统的建设维护提供参考。     

给水工艺对不同分子质量有机物的去除规律研究

通过给水处理工艺中试系统,研究了溶解性有机碳(DOC)在各工艺单元出水640的分子质量分布,探讨了对不同分子质量有机物的去除规律.曝气生物滤池(BAF)去除最好的是相对分子质量在3k～10k的DOC:预臭氧化对相对分子质量＞1k的DOC均有去除效果.而对相对分子质量＜1k的DOC则产生了积累;常规处理对＞30k和10k～30k的DOC去除率分别达到93.7%和78.4%,而对10k以下的DOC去除作用不强;因可被臭氧分解的有机物基本在预臭氧阶段已处理掉,所以后臭氧对有机物去除不明显;炭滤池对各分子质量段的有机物均有去除效果,尤其对BAF和常规处理效果不好的相对分子质量＜10k的DOC去除效果很好.     

生物稳定性及生物稳定水制备工艺研究

生物稳定性是评价饮用水水质的重要指标。饮用水常规处理工艺不能有效去除AOC和BDOC,加氯消毒甚至会使AOC值升高,以太湖、黄浦江和长江为水源的常规处理工艺水厂的出厂水均不能满足生物稳定性的要求。曝气生物滤池和臭氧生物活性炭处理单元可以有效去除AOC和BDOC,曝气生物滤池+混凝气浮+臭氧生物活性炭+砂滤组合工艺出水经过消毒后能够满足生物稳定性的要求。     

饮用水深度处理系统溶解性有机物的变化与组成特性

采用混凝、沉淀、砂滤联合臭氧、生物活性炭构建饮用水深度处理系统,以黄浦江原水为研究对象,研究该系统对各类有机物的去除效能,探讨溶解性有机物在系统中的变化与组成特性。结果表明：黄浦江原水中以分子量小于3000的有机物为主,占总溶解性有机物的55.9%;常规单元、臭氧、生物活性炭对溶解性有机物的去除有功能互补性,常规单元对分子量大于10000的有机物去除率达61.1%,而对分子量小于3000的DOC去除率仅为7.9%,臭氧氧化可使难降解有机物改性为小分子量有机物,经生物活性炭单元后,分子量小于3000的DOC去除率达到28.9%;微量有机物主要通过臭氧、生物活性炭单元被去除,生物活性炭单元出水中微量有机物种类降低至30种,浓度降低67.4%,三氯甲烷生成势去除率为相似文献   

臭氧-生物活性炭-砂滤组合工艺运行效果分析

介绍某水厂采用"臭氧-生物活性炭-砂滤"深度处理组合工艺处理引黄水库水,考察了不同进水浑浊度对组合工艺长期运行效果的影响,同时对组合工艺各单元的有机物种类及分子量分布的变化进行了分析。长期运行结果表明:(1)组合工艺对不同水质条件下的有机物指标有较高的去除效果,较高的温度有利于水中有机污染物的去除。(2)臭氧的主要作用在于将大分子量的有机物氧化为小分子量有机物,故臭氧生物活性炭工艺对COD_(Mn)2、UV_(254)和DOC有良好的去除作用。整个工艺对氨氮的去除率在40%~50%,对亚硝酸盐氮的去除率在80%~90%。(3)臭氧活性炭工艺对可生物降解有机物有较好的去除效果,砂滤工艺主要去除D0CDA。(4)上向流BAC柱活性炭颗粒间空隙率较大,降低了对浊度的机械截留,其后置的砂滤池可起到稳定出水浊度,保证出水微生物安全性的作用。     

常规处理与深度处理工艺对南京长江原水中有机物去除效能比较

以长江南京段原水为研究对象,通过常规处理及深度处理工艺(强化过滤工艺和生物活性炭工艺)对长江南京段水源水中有机物的去除效能进行对比研究。结果表明常规工艺对CODMn、UV254、DOC及BDOC的去除率分别为30%、41%、27%及25%。强化常规工艺和生物活性炭工艺各指标的去除率分别为34%和52%、48%和50%、37%和40%及74%和82%。强化过滤工艺及生物活性炭工艺对1,2,4-三氯苯的去除效果明显,能显著提高出水水质。常规工艺对MW大于5 kDa的有机物去除效果明显,强化过滤工艺对MW小于1 kDa的有机物去除率大于25%,生物活性炭工艺对各个分子量区间的去除效果都比较好,特别是对原水中占多数的MW小于1 kDa的有机物去除率大于30%。     

水中残留有机物分子量分布特征和对膜性能的影响

本试验分析了城市二级处理水的残留有机物分子量分布特征及对超滤膜过滤透水性能的影响，并利用混凝法，活性炭吸附，臭氧-活性炭吸附进行了处理。研究结果表明：（1）城市污水厂二级出水中溶解态有机物主要集中在〈2k分子量区间上；（2）混凝处理后，高分子量有机物低分子化效果明显；PAC吸附能有效去除小分子量有机物；臭氧-PAC联用，大分子量有机物和小分子量有机物所占比例均有所下降，表明臭氧氧化与PAC吸附联用在去除有机物方面具有很好的互补性；（3）分子量分布对原水的透水通量影响较大；选择混凝、PAC或臭氧-PAC等作为膜法处理的预处理单元，对城市污水再生处理具有重要价值。     

典型水处理工艺处理黄浦江原水有机物变化规律初探

该文从分子量转化的角度对水体中有机物在水处理工艺过程中的转化进行了研究.针对特定的水质特征(小分子有机物居多),比较了3种不同的氧化剂(臭氧、氯和高锰酸钾)对有机物分子量(molecular weight,MW)的转化情况.试验证实臭氧氧化可明显减少MW＞30 kDa的有机物含量,进一步通过絮凝沉淀和过滤工艺可使MW＞...     

饮用水BDOC、AOC处理技术研究进展

围绕饮用水的生物稳定性，分析了常规水处理工艺对BDOC、AOC的影响，提出强化混凝和强化过滤的方法可改善出厂水的生物稳定性。讨论了生物氧化、臭氧氧化、活性炭吸附、臭氧-生物活性炭及膜过滤等工艺对饮用水中BDOC、AOC的去除效果，提出了提高出厂水生物稳定性的措施。     

Ozone Assisted Biological Treatment Of Industrial Wastewaters Containing Biorefractory Compound

Ozone pretreatment studies of organic compounds that are difficult to biodegrade were conducted to evaluate the effects of ozonation on biodegradability of these compounds. Initial testing was conducted in batch activated sludge experiments with and without preozonation to evaluate the impacts of ozonation on the ultimate BOD/COD and ultimate BOD/TOC ratios of these compounds. Experimental results indicated wastewater preozonation to be an effective pretreatment step for some compounds, ineffective for other compounds and detrimental to biological treatment of still other compounds. These same compounds were then investigated in continuous flow, complete–mix activated sludge systems. Complete material balances, including influent, effluent, waste sludge and off–gas specific compound analyses, were conducted so that the actual fate of the compound could be determined. Removal mechanisms of the ozonated or unozonated compound were then determined to be biodegradation, stripping, or sorption to the biomass. Three compounds were investigated: acrylonitrile, 2,4 dinitrophenol, and 1,2 dichloropropane.     

The Effect Of Preozonation On The Control Of Trihal Omethane Formation

A study was made to obtain a better understanding of the manner in which preozonation affects trihalomethane (THM) formation with respect to humic acid, citric acid, and 11 aromatic compounds which were components of humic acid, all in dilute aqueous medium. Ozonation before chlorination is able tonotonly decrease, butalso increase the concentrations of THM precursors. The compounds which are inherently high THM precursors, such as resorcinol, aniline, salicyl-aldehyde, phenol, andp-hydroxybenzoic acid, are controlled with respect tothe increase inthe amount ofozone consumed, but the compounds which have essentially no or alow potential for chloroform formation, such as hydroquinone. salicylic acid, methoxybenzene. benzaldehyde. and benzole acid, produce their maximum THM levels at a certain value of ozone consumed. When 1mg of organic carbon consumes more than 8 mg of ozone, THM formation from thetested aromatic compounds isdepressed by ozone.

Aliphatic carbonyl compounds which are the products resulting from the ozonation of aromatic compounds are not significant THM precursors. The preozonation of humic acid is not as effective in reducing its THM formation potential (THMFP) as when simple aromatic compounds are treated. However, the organic materials in the effluent from a biological treatment process usually have a high THMFP, in comparison with organic compounds which are contained in raw wastes. Therefore, there is a limitation in the effectiveness of utilizing biological treatment to remove the precursors of THM.     

臭氧-生物活性炭联合应用提高电厂补给水水质

针对于目前火力发电厂补给水中的有机物含量过高的问题,采用臭氧-生物活性炭(O3-BAC)工艺对其进行处理。实验结果表明,当O3的投加质量浓度为3mg／L、接触时间为20min、炭柱停留时间为20min,O3-BAC工艺对CODMn的平均去除率为52．57％,UV254的平均去除率为68．15％。同时O3和BAC协同作用使O3-BAC的活性炭柱出水水质稳定,延长了活性炭的使用寿命。实验表明,O3-BAC工艺在锅炉补给水处理中的应用可行。     

Effects of Ozonation on Molecular Weight Distribution of Humic Substances and Coagulation Processes – A Case Study: The Úzquiza Reservoir Water

In this article the influence of preozonation on the effectiveness of NOM removal via coagulation processes will be studied (focusing on the influence of the calcium hardness) as well as changes in MW (molecular weight) distribution of humic substances caused by ozonation. Additionally, THMFP removal in both ozonation and preozonation-coagulation processes is assessed. Three different types of water have been used in this study: a natural water from the Úzquiza Reservoir (Burgos, Spain), a synthetic water prepared using natural fulvic acids extracted from the Úzquiza Reservoir and a synthetic water prepared using a commercially supplied humic acid. Molecular weights of humic substances were determined using high-performance size exclusion chromatography (HPSEC); average molecular weights calculated for the unozonated humic substances are 4500 Da for the commercial humic acids and 1000 Da for the natural fulvic acids extracted from the Úzquiza Reservoir. Preozonation shifted the molecular weight distribution of humic substances (both humic and fulvic acids) towards lower average molecular weight values. For the natural water from the Úzquiza Reservoir (with low levels of calcium hardness and hydrophobic fraction (humic substances) being the main fraction of NOM), preozonation has a negative effect on the effectiveness of the coagulation process for NOM removal: the percentages of TOC removal via coagulation decrease with increasing ozone dosage; the maximum TOC removal (33%) is achieved for the unozonated water. Also for this water, ozonation reduced 5–25% of THMFP with ozone doses varying from 0.25 to 2.5 mg O₃/L. A preferential THMFP removal, that is to say, higher reduction in THMFP (43%) relative to TOC (28%) is achieved by the coagulation-flocculation process; this also occurs when preozonation is used, independently of ozone dosage.     

The Influence of Ozonation on the GAC Adsorbability of Organic Substances in Activated Sludge Effluent

The effect of preozonation on activated sludge effluent before activated carbon treatment was evaluated in terms of its effect on the adsorption process. It was found that the total removal of organic substances by the combined action of ozone and activated carbon was superior than by either ozone or activated carbon separately. Although ozonation leads to a decrease in the adsorbability of organic substances, the overall removal of organic substances is not impaired except during the early stages of operation before an effective biogrowth is established. Preozonation extends the operational life of activated carbon. This is explained, in part, by improved desorption and biodegradation of the adsorbate.