不同絮凝剂对生活污水处理中溶解性有机物的影响

选择不同絮凝剂对生活污水进行絮凝处理,考察了 COD 的去除率,并结合紫外-可见光谱、三维荧光光谱对污水中的溶解性有机物（DOM）进行了表征和分析,以阐明不同絮凝剂对生活污水中 DOM 的去除特征。结果表明：阳离子的絮凝剂对 COD 的去除效果更好,Fe Cl₃和微生物絮凝剂 SMP 联合使用可去除 44.0% 的 COD,阳离子型聚丙烯酰胺可去除 57.4% 的 COD;紫外分析发现絮凝剂对含苯环的芳香族化合物和含多个共轭双键物质的去除能力强;三维荧光分析表明 PAM 类絮凝剂对类腐殖酸物质的去除效果好,Fe Cl₃+SMP 可去除 52% 的类色氨酸物质,Fe Cl₃可去除 60.2% 的类溶解性微生物代谢产物;絮凝处理使得 DOM 荧光峰发生蓝移,即部分 DOM 转化为芳香性较低的物质,这有利于后续的污水处理工艺的运行。     

微塑料与植物来源溶解性有机质的相互作用研究

溶解性有机质(DOM)是广泛存在于各种天然水体中的一类具有复杂结构组成和环境行为的有机混合物,其行为与生态系统有机碳循环密切相关。微塑料作为一种全球性的新型污染物,具有残骸难以降解、在水环境中可长期保存等特点,已经引起人们广泛关注。目前,国内外对于微塑料污染物的研究大多集中在微塑料丰度、赋存状态以及其对水生生物的毒性研究方面,仅少量研究涉及关于微塑料与DOM、行为与效应之间的关系。本实验以典型微塑料和外源输入DOM(芦苇提取)为研究对象,进行微塑料与DOM的共培养,研究微塑料对DOM的吸附和释放作用。通过分析DOM紫外-可见吸收光谱法及三维荧光光谱法的结果表明,微塑料在水体富集过程中会吸附水体中的DOM,引起水体中类腐殖酸和类蛋白荧光物质总量的减少。并且水体中微塑料主要吸附植物来源DOM中的类色氨酸T和类腐殖质C组分并释放腐殖质类物质,吸附效果与微塑料浓度相关。本实验的研究结果对了解微塑料污染具有重要的科学意义。     

金泽水库水体中溶解性有机物的光谱学特征

为追溯新建水源库区污染物质的来源及变化,选取上海市金泽水库为研究区,利用三维荧光光谱结合平行因子分析法,研究金泽水库水体溶解性有机物(DOM)组成结构及空间分布特征。结果表明:DOM由类蛋白质组分、类色氨酸组分、类富里酸组分组成;通过计算腐化指数(HIX)、生物源指数(BIX)和荧光指数(FI),得出水体DOM是腐化程度很低、具有强生物活性,主要受生物源作用;在3月和6月总荧光强度表现为前置库区深度净化区生态净化区,12月总荧光强度随水流方向升高,类富里酸在不同月份均随着水流方向降低;总荧光强度随时间的变化表现为3月12月6月。     

不同水源特征水库中溶解性有机物的光学特性对比

为考察A水库(“引黄工程”水源水库)与B水库(普通类型水库)的溶解性有机物(DOM)在相对分子质量大小、组成特征及来源方面的差异,采用紫外-可见光谱技术以及三维荧光光谱技术结合平行因子分析法,针对A水库和B水库水体中DOM的吸收参数特征和荧光特征进行了研究。结果显示：A水库和B水库的DOM均有较强的自生源特征,但两水库的DOM在组成特征和来源上存在一定差异。B水库样本中存在长波类腐殖质C1(E_x=350 nm,E_m=454 nm)、类色氨酸物质C2(E_x=300 nm,E_m=361 nm)和类色氨酸C3(E_x=220 nm/250 nm,E_m=347 nm)3个荧光组分,而A水库样本中存在长波类腐殖质C1、类色氨酸物质C2两个荧光组分,说明A水库的组成特征相对更加简单。DOM吸收参数特征分析显示,A水库水质状况良好,其DOM相对分子质量较大,主要来自自生源;而B水库处于富营养状态,其DOM相对分子质量较小,富里酸成分和水体芳香性较高,水生环境中维管束植物输...     

一体式膜生物反应器深度处理垃圾渗滤液的适用性研究

采用自制一体式膜生物反应器(MBR)深度处理垃圾渗滤液(COD 800～1 300 mg·L^-1、氨氮40～80 mg·L^-1),考察了MBR启动及优化条件下连续运行状况。结果表明,启动11 d后COD、氨氮去除率分别达到63.65%、81.78%;在HRT为24 h、DO为3～4 mg·L^-1的最优条件下运行28 d, COD、氨氮去除率分别达到80%以上、90%以上,但跨膜压差从20.3 kPa增至46.8 kPa,表明膜污染产生且逐渐加剧;傅立叶变换红外光谱分析表明,膜面污染物与污泥的有机官能团相似;荧光光谱分析表明,膜面污染物主要为多糖类、类色氨酸蛋白质、类富里酸和类腐殖酸;对比分析MBR稳定运行15 d和28 d时的胞外聚合物和溶解性微生物产物的特征荧光峰,发现膜面污染物的特征荧光峰与胞外聚合物、溶解性微生物产物的荧光峰相似,且与胞外聚合物的相似性更高,说明胞外聚合物为膜污染的主要来源,溶解性微生物产物为膜污染的次要来源,因此MBR长期稳定运行需重点关注胞外聚合物的控制。     

三维荧光光谱表征饮用水中溶解性有机物研究进展

荧光技术目前已经被广泛地应用于溶解性有机物(DOM)的表征。其中荧光激发发射矩阵光谱(EEM),也称为三维荧光(3D-EEM)或荧光指纹是最主要的方法之一。目前，三维荧光已经被开发并用于表征饮用水处理工艺对有机物的去除效果。该文综述了目前主要的三维荧光分析方法，并总结了三维荧光在饮用水处理工艺中的运用及其存在的问题。     

生态型水库水体有机物荧光特性分析

运用三维荧光光谱法分析生态型水库金泽水库水体中溶解性有机物(DOM)的来源和特性.结果 表明,金泽水库水体DOM荧光特性物质主要由类色氨酸、类酪氨酸和芳香类蛋白组成.在空间上,冬季水体DOM荧光强度为生态蓄水区＜生态净化区＜前置库区＜取水口,夏季水体DOM荧光强度为取水口＜前置库区＜生态净化区＜生态蓄水区;在时间上,水库水体DOM荧光峰强度为夏季＜冬季＜春季.通过计算荧光指数(FI)和生物指数(BIX),说明金泽水库DOM主要为生物源兼具强生物活性.     

不同碳源反硝化滤池进出水中溶解性有机物对比分析

以某城市污水处理厂二级出水为反硝化滤池进水,利用分子排阻色谱、三维荧光(EEM)及溶解性微生物代谢产物(SMP)测定等不同分析方法对不同碳源反硝化生物滤池进出水中的溶解性有机物(DOM)进行对比研究。结果表明,滤池进水DOM中小分子物质含量最高,其中分子量为1 kDa的有机物约占总有机物的50%,分子量10 kDa的大分子有机物约占7%。经过反硝化滤池,出水有机物种类不变,小分子有机物出水浓度下降为进水的50%,说明滤池对小分子物质有一定的去除作用。SMP测定结果表明,滤池进水中主要的SMP物质为腐植酸,约占SMP总含量的70%。在整个过滤周期内,SMP的总量变化不大,反冲洗气水冲和水冲阶段SMP的浓度增加显著。EEM分析表明,滤池正常运行时,进出水中的DOM主要成分为可见腐植质(λ_(ex)/λ_(em)=330/425)和UV腐植质(λ_(ex)/λ_(em)=230/430);反冲洗阶段,DOM含量增加,且出现类蛋白、类色氨酸;整个过滤周期内有机物的含量基本不变,说明反硝化生物滤池不能对腐植酸类物质进行降解。     

投加氯化铁对SMBR工艺效能及膜污染的影响

试验研究了浸没式膜生物反应器(SMBR)中FeCl_3不同投加量对出水水质以及膜污染的影响.结果表明,不同投加量对于COD、NH_3-N的去除效率影响不显著;随着FeCl_3投加量的增加,总氮(TN)去除效率略有提高.投加适量FeCl_3,可以增强化学和生物协同除磷作用.溶解性胞外聚合物(EPSs)中多糖浓度、松散附着胞外聚合物(LB)中蛋白质和腐殖酸浓度与半透膜压(TMP)的增长存在明显的相关性,说明EPSs中多糖、LB中蛋白质和腐殖酸均是导致膜污染的主要因素.FeCl_3最佳投加量范围为15～30mg·L~(-1),此时活性污泥形成了良好的菌胶团,TMP增长速度最慢,膜污染程度最轻.而当投加量进一步增大到60 mg·L~(-1)和120 mg·L~(-1)时,生物铁结构变得密实,膜污染程度加剧;其次过多FeCl_3本身也增加了的膜污染负荷.     

丝状菌对膜生物反应器中溶解性有机物及膜污染的影响

该文以处理超市废水实际MBR工程为基础,通过对污泥膨胀过程中进出水、溶解性微生物产物(SMP)和胞外聚合物(EPS)中的溶解性有机物(DOM)特性的研究,发现SMP和进出水的DOM主要以蛋白质为主,且SMP较EPS含有更多大分子物质;同时发现SMP比EPS和进出水中含有更多50～100 kDa、100～500 kDa和...     

Magnetic Ion Exchange (MIEX) Treatment of Surface Water,Groundwater, and Landfill Leachate Wastewater: Effect on Organic Matter Fluorescence

Dissolved organic matter (DOM) is increasing in many drinking water supplies, which can have adverse impacts on treatment. Magnetic ion exchange (MIEX) is an advanced treatment process that has been shown to effectively remove DOM from different water sources. DOM removal efficiency is typically determined through dissolved organic carbon (DOC) and ultraviolet absorbance (UVA) measurements, but these methods can be limited in the amount of information they provide on DOM. Fluorescence spectroscopy has been suggested as a more robust characterization technique for monitoring DOM, but there remain gaps in knowledge between DOM removal processes and fluorescence characterization of DOM. Accordingly, the goal of this research was to evaluate the impact of MIEX treatment on DOM fluorescence for diverse water sources. MIEX jar tests were conducted using surface water, synthetic water, groundwater, and landfill leachate wastewater, and analyzed for DOC, UVA, and fluorescence excitation-emission matrix (EEM). Fluorescence EEMs were used to determine fluorophore location, intensity, and fluorescence index. MIEX removal of DOC and UVA were strongly correlated with MIEX removal of peak fluorescence intensity across all water sources. Peak fluorescence location indicated that MIEX preferentially removed terrestrial DOM. Fluorescence is a promising tool for monitoring DOM removal efficiency by MIEX treatment.     

滤池反冲水回流混凝工艺中溶解性有机物荧光特性

引言湖库水作为典型的低浊水源水,通常由于低的颗粒物浓度、小的颗粒尺寸、低的碰撞和聚集效率以及有机物更强亲水性,使常规混凝存在处理效果差、药剂用量大、产泥量多和出水残余铝含量高等缺点[1]。净水厂排泥水、滤池反冲洗水(FBWW)及二者的混合废水通常含有一定量悬浮固体、有机或     

典型污染物对膜蒸馏过程膜污染的影响

选取腐殖酸、卵清蛋白、硅溶胶、碳酸钙等作为实际水体中典型污染物配制原水,以实验室自制的聚偏氟乙烯中空纤维膜对配制的污染物原水进行膜蒸馏试验。通过监测通量的衰减及产水侧水质的变化考察不同污染物及污染物复配体系对膜蒸馏性能的影响。结果表明,膜蒸馏操作初期,有机质、胶体等在钙离子的作用下形成污染物聚集,加速过程通量的衰减并沉积在膜材料表面。对于有机类污染物,钙离子通过与有机类污染物分子上的官能团相互作用,络合有机质从而形成污染物聚集体;对于胶体类污染物,钙离子通过削弱两胶体粒子间的排斥作用促成胶体粒子的聚合,形成胶体类污染物聚集体,而钙离子并不构成胶体类污染物聚集体的化学组成。     

煤气化废水溶解性有机物水质特征研究

煤气化废水中的溶解性有机物(DOM)决定着处理药剂和微生物生长等,直接影响废水处理工程效果,DOM的光谱表征可反映各组分在氧化、降解或吸附等方面的特性。在分析某煤气化生产尿素企业的废水产生节点基础上,采集脱酚氨后废水,采用树脂分离方法对气化废水中的DOM进行6组分(HoA、HoB、HoN、HiA、HiB、HiN)分离,通过紫外-可见光谱、三维荧光光谱等分析方法对其水质特征进行分析。结果表明:废水DOM中HoA、HoN组分占比高达43.21%和33.65%,废水中含有较多非饱和结构的芳香族化合物;脱酚后废水各组分的E300/E400数值都较低,为2.88~5.00,说明废水的腐植化程度很高,主要为难生化降解的苯环结构物质;三维荧光光谱分析表明煤气化废水DOM各组分的最强荧光响应区域对应的有机物质主要包括类腐植酸、类富里酸、类酪氨酸以及类色氨酸这四大类有机物,为控制和处理煤气化废水中有机污染物提供理论依据。     

MBR工艺处理餐饮废水中DOM组分的特性

通过组分划分试验,对平板膜生物反应器中的溶解性有机物进行分离得到四种组分,并借助于分子量技术、荧光技术深入研究各组分对膜污染的影响。结果表明强疏水性（HPO）组分表现出最强的膜污染趋势,而弱疏水性（TPI）组分呈现出最高的可生物降解性,生物降解去除率可达91．8％。     

竹红菌乙素对人红细胞膜蛋白荧光猝灭机理的研究

本文利用人红细胞膜蛋白内源荧光(主要指色氨酸),经加入不同的竹红菌乙素之后,引起了荧光猝灭现象,根据荧光猝灭原理分别从吸收光谱,荧光光谱,稳态变温实验和瞬态荧光等技术分析了上述的猝灭过程,实验证明:该猝灭是以动态碰撞过程为主要作用机理,据此作者提出了乙素可以用于生物膜体系的蛋白质荧光猝灭剂的理由。     

Characterization of dissolved compounds in submerged anaerobic membrane bioreactors (SAMBRs)

Two submerged anaerobic membrane bioreactors (SAMBRs) with essentially 100% cell recycle (150 days retention time, SRT), one with powdered activated carbon addition (PAC 1.7 g L^?1) and one without, were continuously fed a low‐strength feed (450 mg COD L^?1) in order to investigate membrane fouling and to characterize the foulants. The SAMBR which did not receive PAC experienced more fouling, and the molecular weight (MW) distribution showed that there was a greater amount of high‐MW compounds in this reactor when compared with the reactor with PAC. Size exclusion chromatography showed that although extracellular polymeric substances (EPS) seemed to contribute to the soluble chemical oxygen demand (COD) inside the reactor, it was mainly rejected by the membrane. High‐MW protein and carbohydrate material originating mainly from cell lysis and EPS seemed to be the main organics that contributed to the internal fouling of the membrane. Copyright © 2006 Society of Chemical Industry     

An Insight into Dissolved Organic Matter Removal Characteristics of Recycling Filter Backwash Water: A Comparative Study

It is necessary to put all aspects,,namely raw water characteristics, corresponding FBWW, and coagulation mechanisms, i.e., charge neutralization and sweep flocculation together to make clear the dissolved organic matter (DOM) removal characteristics and the fate of fractionations in recycle design. The DOM characteristics of molecular weight (MW) distribution, hydrophobicity, and fluorescence in source water W1 (synthesized water) and W2 (“Longtan” lake water), FBWW and treated water samples therefore are identified, and three recycling ratios of 2%, 5%, and 8% as compared to control (0%) are conducted. It is found that DOM within FBWW becomes more hydrophilic and lower MW as compared to corresponding source water. Recycling trials indicate that higher DOM concentrations and more low-MW fractions are not of any benefit to enhance UV₂₅₄ and DOC removal. Hydrophobic acid can be further eliminated in case recycling particles mainly produced by sweep flocculation, while weakly hydrophobic acid and hydrophilic fraction can be enhanced and removed under recycling particles mainly formed by charge neutralization. Higher molecular weight fraction (>30 kDa) exhibits potentially enhanced removal at preferred recycling ratio of 5%. Fluorescent characteristics analysis demonstrate that recycling FBWW can effectively improve humic-like substances removal, but the protein-like matters are resistant to be eliminated with unvaried structure.     

Sorption of Perfluorooctanoic Acid (PFOA) onto Sediment in the Presence of Dissolved Natural Organics

The abundance of perfluorooctanoic acid (PFOA) in the aquatic environment makes it important to understand the influence of important parameters affecting the partition of PFOA onto sediment. With a focus on the influence by dissolved organic matter (DOM), we investigated the sorption of PFOA to river sediment downstream of a semiconductor and optoelectronic industrial complex that discharged wastewater with a considerable amount of PFOA in it. The dominant components of the sediment were silica oxide (～14%) and iron oxide (～2%). The sorption density of PFOA was not significantly affected by solution pH and ionic strength. The combinations of low pH-high ionic strength and high pH-low ionic strength favored partitioning of PFOA to the sediment. The sorption density of PFOA to sediment ranged from 0.41 to 1.43 µg/m², with the presence of DOM in the aqueous phase reducing the affinity of PFOA toward the sediment. The sorption of PFOA seemed to be facilitated not by electrostatic but by hydrophobic interactions. The PFOA-sediment sorption equilibration required a duration exceeding 12 d. This study revealed DOM as an important solution-specific parameter in sorption studies. The influence of DOM on PFOA sorption provides a useful reference to understand PFOA partition in the aqueous environment. Supplemental materials are available for this article. Go to the publisher's online edition of Separation Science & Technology to view the free supplemental file.