沸石生物联合吸附再生工艺中溶解性有机物的特性变化

利用三维荧光技术(EEM)和凝胶过滤色谱法(GFC)研究了沸石生物联合吸附再生(ZCS)工艺中溶解性有机物(DOM)在系统中的变化规律.结果表明,生活污水DOM中主要的荧光物质有类蛋白质(荧光峰A和B)和类腐殖质(荧光峰C),经ZCS工艺处理后,荧光峰B较峰A的强度降低更多,说明类蛋白质的组成结构发生了变化;荧光峰C削...     

生物强化组合工艺处理河水的三维荧光及生物多样性分析

通过对受污染地表水进行生物滤池-臭氧预氧化-生物活性炭滤池工艺处理,考察生物强化条件下该项工艺对河水中主要污染物的净化效果,并采用EEM光谱技术进行了溶解性有机物变化和去除规律分析,利用PCR-DGGE技术进行各单元中微生物多样性对比分析。结果表明,生物强化组合工艺系统出水水质主要指标已达到/接近地表水环境质量标准(GB 3838-2002)Ⅳ类限值,生物强化滤池填料中微生物多样性指数和物种数均高于其他工艺单元。受污染河水DOM中主要的荧光物质有类芳香族蛋白质(荧光峰A、B和E)及类腐殖酸(荧光峰C)及类富里酸(荧光峰D),其中,A峰、B峰与E峰的中心位置分别位于225/340 nm、275/336 nm和225/298 nm,各特征荧光峰强度发生明显改变表明,污水中溶解性有机物的含量随系统处理过程而变化。     

基于三维荧光光谱技术解析不同微生物法净化黑臭水体的效果

应用曝气、菌剂+曝气、生物促生剂+曝气、菌剂+生物促生剂+曝气4种微生物技术净化黑臭水体,分别考察了进水中溶解性有机物(DOM)的特征和来源及出水中DOM的特征和效果,采用三维荧光(EEM)光谱技术与平行因子(PARAFAC)模型相结合的方式对进出水DOM进行了分析。结果表明,不同处理方式下进出水DOM的不同组分荧光峰强度变化存在较明显的差异,经过菌剂和生物促生剂联合处理之后,对类腐殖质等难降解物质削减效果最好。FI、HIX和BIX指数分析表明各处理水样中的DOM整体处于较强的自生源特征。利用主成分分析法(PCA)对影响黑臭水体DOM的主要因素及其贡献量研究发现:第1主成分表现为陆源类腐殖质和生物源类腐殖质共存的现象,对水体中DOM的贡献率为54.98%;第2主成分反映了以微生物代谢过程为代表的内源污染,对水体中DOM的贡献率为26.56%。因此,利用三维荧光分析能够较好的反映水中DOM的去除情况,易于实时在线监测,对黑臭水治理具有重要意义。     

MBR工艺中溶解性有机物的分子量和EEM解析

采用凝胶过滤色谱(GFC)分子量测定技术和三维荧光(EEM)光谱技术,对平板膜-生物反应器工艺应用于餐饮废水和粪便污水处理的工程实例进行研究,对比分析2套工艺中的调节池水和出水的溶解性有机物(DOM)及污泥胞外聚合物(EPS)的性质变化.研究表明,餐饮废水处理过程的调节池水DOM中大分子(＞100 kDa)物质比例为6...     

猪场沼液处理过程中溶解性有机质的光谱学特征

猪场沼液无序排放会导致严重的水环境问题,探索猪场沼液处理过程中有机物变化的检测方法,可以为养殖废水处理和排放管控提供技术支撑。利用三维荧光光谱法和紫外—可见分光光度法对猪场沼液处理过程中溶解性有机物(DOM)的光学参数进行分析。结果表明:猪场沼液DOM的三维荧光图谱显示其主要存在类腐殖质、类色氨酸和类酪氨酸3类物质,以类腐殖质物质为主;经AO处理后猪场沼液中的类色氨酸物质部分转化为类酪氨酸物质;经序批式生物膜反应器(SBBR,由SBBR1和SBBR2组成)工艺处理后,类色氨物质全部被分解转化。猪场沼液经SBBR2和氧化塘处理后,DOM浓度和各荧光组分含量有所升高,需要进一步调试优化。DOM在254nm处的光吸收系数(A254)、各特征荧光峰强度以及特征荧光峰总强度与TN、溶解性有机碳(DOC)均具有显著正相关性,因此利用猪场沼液DOM的光谱学特征,不仅可以指示废水中DOM成分的转化状况,也可作为判断工艺流程处理效果的依据,还能较好地表征TN和DOC,具有广泛的应用前景。     

切削液废水处理过程中溶解性有机物分子质量分布和光谱特征的转化规律

以隔油-混凝沉淀-水解酸化-好氧共代谢为组合工艺处理切削液废水,探究各处理单元对不同种类有机物的转化规律和去除能力;对各处理单元出水中的溶解性有机物(DOM),采用超滤膜法进行分子质量分级,应用紫外-可见吸收光谱、三维荧光光谱等方法对各单元出水及其滤后液进行了分析。结果表明,隔油池出水DOM分子质量主要分布在1 kDa小分子质量区间和100 kDa的大分子质量区间,分子质量占比分别为46.04%、42.79%,混凝沉淀对大分子质量的DOM有较好的去除效果,混凝沉淀出水、水解酸化池出水、好氧池出水的DOM主要分布在1 kDa区间。切削液废水处理过程中出现5个荧光峰,其中峰A和峰B可能为多环芳香烃和杂环化合物的混合物;峰C为石油类;峰D可能是废切削液中滋生的微生物和细菌的细胞物质及其分泌物或单环芳香烃;峰E可能为杂环化合物或多环芳烃类腐殖酸。经一级处理(隔油和混凝沉淀)后峰A和峰B的去除率分别为60%和35%;峰C和峰D去除率均大于99%。经二级处理(水解酸化和好氧共代谢),峰A和峰B的去除率分别为23%和48%。该工艺流程对切削液废水中的有机物有较好的去除效果,石油类、COD、TOC、BOD_5的总去除率可达99.99%、98.81%、98.74%、99.78%,达到了《污水排入城镇下水道水质标准》中的B级标准。     

SBR-混凝处理渗滤液过程中有机物的变化特征

考察了SBR-混凝组合工艺对垃圾渗滤液中溶解性有机物(DOM)不同分子量区间物质及组分腐殖酸(HA)、富里酸(FA)和亲水性有机物(Hy I)的去除效果,同时利用傅里叶红外光谱及三维荧光光谱对处理过程中DOM各组分变化特性进行了分析。结果表明,组合工艺对表观分子量为2 000~4 000及2 000的DOM去除率分别为89.3%和72.1%;对渗滤液DOM组分HA、FA和Hy I的去除率分别为-52.0%、73.1%和77.1%。红外光谱显示,DOM各组分都含有醇、羧酸、脂等多种有机物,SBR对糖、醇、羧酸等去除效果较好,而混凝对脂肪族及芳香族化合物去除效果较好;三维荧光光谱分析表明,经组合工艺处理,DOM各组分荧光峰强度及复杂化程度明显降低,且SBR工艺对色氨酸等类蛋白物质去除效果较好,混凝工艺对类腐殖酸、类富里酸等大分子物质的去除效果较好。     

污水处理对黑水/灰水中溶解性有机物紫外光谱及荧光光谱特性的影响

为了考察黑水/灰水中溶解性有机物(DOM)光谱特征在污水处理过程中的变化规律以及生物处理前后黑水/灰水中DOM特性上的异同,对污水处理过程中黑水/灰水DOM的紫外光谱及荧光光谱特征进行了测定分析。结果表明,黑水原水中DOM的含量远高于灰水,且含有较多难降解有机物。生物处理可实现对黑水与灰水中易降解DOM的有效去除,MBR系统中的膜分离过程也可以起到截留溶解性有机物的作用。经MBR处理后,同黑水出水相比,灰水出水中的DOM含量更低,且主要为饱和有机物,苯环C骨架的聚合程度较高,THMs生成活性更低。生物处理过程可有效去除黑水/灰水中蛋白质类物质与易降解腐殖质类物质。生物处理后,黑水与灰水的蛋白峰均消失,黑水出水类腐殖酸峰F荧光强度高于灰水出水。与黑水出水相比,灰水出水更适用作再生水加以回收利用。     

造纸工业园区污水处理厂溶解性有机物迁移转化规律

在对某造纸工业园区污水处理厂污染物变化规律分析的基础上,采用UV-vis光谱、凝胶色谱和三维荧光等指纹图谱手段对溶解性有机物(DOM)特性进行表征。结果表明,该工业园区污水处理厂能够有效去除以造纸废水为主的混合污水中的有机污染物。UV-vis光谱和凝胶色谱分析表明:水解酸化可将大分子有机物分解成小分子,腐殖化程度降低;高级氧化深度处理后小分子物质所占比例明显增加。三维荧光光谱结果表明,DOM中主要的荧光物质包括色氨酸类蛋白质、芳香族类蛋白质、类腐殖酸、类富里酸物质和酪氨酸类蛋白质。水解酸化可以提高芳香族类蛋白质、类腐殖酸和类富里酸的含量。高级氧化则能有效降低类蛋白质和类腐殖酸物质的含量。     

膜-生物反应器处理餐饮废水过程中溶解性有机物的迁移变化特性研究

借助于凝胶过滤色谱(GFC)分子量测定技术和三维荧光(EEM)光谱技术,对膜一生物反应器(MBR)处理餐饮废水过程中溶解性有机物(DOM)的迁移变化特性进行了研究.结果表明,GFC分析中,在析出的前12 min,除了调节池出水,其他各工艺阶段(原水、气浮池出水、MBR出水)水样中均有大分子有机物(分子量＞400 ku)...     

Investigating the effect of landfill leachates on the characteristics of dissolved organic matter in groundwater using excitation–emission matrix fluorescence spectra coupled with fluorescence regional integration and self-organizing map

For the purpose of investigating the effect of landfill leachate on the characteristics of organic matter in groundwater, groundwater samples were collected near and in a landfill site, and dissolved organic matter (DOM) was extracted from the groundwater samples and characterized by excitation–emission matrix (EEM) fluorescence spectra combined with fluorescence regional integration (FRI) and self-organizing map (SOM). The results showed that the groundwater DOM comprised humic-, fulvic-, and protein-like substances. The concentration of humic-like matter showed no obvious variation for all groundwater except the sample collected in the landfill site. Fulvic-like substance content decreased when the groundwater was polluted by landfill leachates. There were two kinds of protein-like matter in the groundwater. One kind was bound to humic-like substances, and its content did not change along with groundwater pollution. However, the other kind was present as “free” molecules or else bound in proteins, and its concentration increased significantly when the groundwater was polluted by landfill leachates. The FRI and SOM methods both can characterize the composition and evolution of DOM in the groundwater. However, the SOM analysis can identify whether protein-like moieties was bound to humic-like matter.     

Characterization of dissolved organic matter in fogwater by excitation–emission matrix fluorescence spectroscopy

Dissolved organic matter (DOM) present in fogwater samples collected in southeastern Louisiana and central-eastern China has been characterized using excitation–emission matrix fluorescence spectroscopy. The goal of the study was to illustrate the utility of fluorescence for obtaining information on the large fraction of organic carbon in fogwaters (typically >40% by weight) that defies characterization in terms of specific chemical compounds without the difficulty inherent in obtaining sufficient fogwater volume to isolate DOM for assessment using other spectroscopic and chemical analyses. Based on the findings of previous studies using other characterization methods, it was anticipated that the unidentified organic carbon fraction would have characteristic peaks associated with humic substances and fluorescent amino acids. Both humic- and protein-like fluorophores were observed in the fogwater spectra and fluorescence-derived indices for the fogwater had similar values to those of soil and sediment porewater. Greater biological character was observed in samples with higher organic carbon concentrations. Fogwaters are shown to contain a mixture of terrestrially- and microbially-derived fluorescent organic material, which is expected to be derived from an array of different sources, such as suspended soil and dust particles, biogenic emissions and organic substances generated by atmospheric processes. The fluorescence results indicate that much of the unidentified organic carbon present in fogwater can be represented by humic-like and biologically-derived substances similar to those present in other aquatic systems, though it should be noted that fluorescent signatures representative of DOM produced by atmospheric processing of organic aerosols may be contributing to or masked by humic-like fluorophores.     

回灌型准好氧填埋场脱氮特性及加速稳定化研究

采用2个模拟填埋生物反应器,1号柱渗滤液简单回灌,2号柱为渗滤液回灌准好氧联合运行方式,研究了渗滤液回灌准好氧生物反应器填埋场的脱氮特性及加速垃圾稳定化特性.研究结果表明:渗滤液回灌准好氧填埋场具有很强的脱氮能力,2号柱由厌氧运行方式改为准好氧条件下,渗滤液中的氨氮和凯式氮浓度分别由最大值的3 198 mg/L和3 345 mg/L降低到第160 d的73 mg/L和81 mg/L,去除率分别为97.7%和97.6%,pH快速升高到8.0左右,COD浓度快速降低.渗滤液中溶解性有机物(DOM)分级结果表明,2号柱HA和FA含量的增加明显快于1号柱.2号柱DOM的三维荧光光谱特性发生了较大变化,荧光基团从60 d结构简单的类蛋白物质转变为95 d结构复杂的类胡敏酸和富里酸物质,而l号柱渗滤液DOM荧光基团一直是结构简单的类蛋白物质.结果表明回灌准好氧生物反应器填埋场的稳定化速度远快于简单回灌的生物反应器填埋场.     

Microbial degradation of dissolved organic matter (DOM) and its influence on phenanthrene-DOM interactions

Microbial degradation-induced changes in the characteristics of dissolved organic matter (DOM), and the subsequent effects on phenanthrene-DOM interactions were investigated based on the microbial incubation of DOM collected from four different sources for 28 d. Partially biodegraded DOM presented higher specific UV absorbance (SUVA), lower protein-like fluorescence, higher humic-like fluorescence, lower aliphatic carbon fraction, and higher hydrophobic neutral fractions compared to the original DOM. Microbial changes in DOM led to an increase in the isotherm nonlinearity as well as the extent of phenanthrene binding. A negative relationship between SUVA and the Freundlich n values was established for the original and the biodegraded DOM, suggesting that aromatic condensed structures may play important roles in providing nonlinear strong binding sites irrespective of microbial degradation. In contrast, there were two separate slopes of the correlations between the percentage of hydrophobic acid (HoA) fraction and the n values for the original and the biodegraded DOM with a higher slope exhibited for the latter, implying that the microbial utilization of oxygen-containing structures in the HoA fractions may contribute to enhancing the associated isotherm nonlinearity.     

Influence of upstream land use on dissolved organic matter and trihalomethane formation potential in watersheds for two different seasons

Different land uses of upstream catchments may affect the quantity and the quality of dissolved organic matter (DOM) in watersheds, but the influence may differ by season. In this study, we examined concentrations and selected spectroscopic properties of DOM and the propensity to form trihalomethanes (THMs) for 19 different middle-sized watersheds across the Han River basin in Korea. Sampling was conducted for non-storm events during pre-monsoon (May) and monsoon seasons (July). The anthropogenic land uses including agricultural and residential areas occupied 2.3 to 49.4 % of the upstream catchments of the watersheds. Non-aromatic, labile, and less condensed DOM structures were more abundant in the monsoon season. Parallel factor analysis (PARAFAC) modeling with fluorescence data demonstrated that a combination of three different fluorescence components could explain the seasonal and the spatial distributions of DOM characteristics. Terrestrial humic-like fluorescence was the most abundant component for all the DOM samples, while protein-like fluorescence became more pronounced for the monsoon season. THM concentrations did not differ between the two seasons. Observed seasonal differences in the concentrations and the characteristics of DOM suggested a greater contribution of groundwater to the streams in watersheds in the monsoon versus the pre-monsoon season. Significant correlations among anthropogenic land use, microbial humic-like fluorescence, and the propensity to form THMs were found only for the pre-monsoon season. Principal component analysis (PCA) demonstrated that, regardless of the season, anthropogenic land uses increased the concentrations of DOM and nutrients but that their effects on the DOM properties were not evident for the monsoon season.     

Quantifying interactions between propranolol and dissolved organic matter (DOM) from different sources using fluorescence spectroscopy

Beta blockers are widely used pharmaceuticals that have been detected in the environment. Interactions between beta blockers and dissolved organic matter (DOM) may mutually alter their environmental behaviors. To assess this potential, propranolol (PRO) was used as a model beta blocker to quantify the complexation with DOM from different sources using the fluorescence quenching titration method. The sources of studied DOM samples were identified by excitation–emission matrix spectroscopy (EEMs) combined with fluorescence regional integration analysis. The results show that PRO intrinsic fluorescence was statically quenched by DOM addition. The resulting binding constants (log K _oc) ranged from 3.90 to 5.20, with the surface-water-filtered DOM samples claiming the lower log K _oc and HA having the highest log K _oc. Log K _oc is negatively correlated with the fluorescence index, biological index, and the percent fluorescence response (P _i,n) of protein-like region (P _I,n) and the P _i,n of microbial byproduct-like region (P _II,n) of DOM EEMs, while it is correlated positively with humification index and the P _i,n of UVC humic-like region (P _III,n). These results indicate that DOM samples from allochthonous materials rich in aromatic and humic-like components would strongly bind PRO in aquatic systems, and autochthonous DOM containing high protein-like components would bind PRO more weakly.     

不同垃圾渗滤液组合处理工艺中DOM的变化特征

为了快速表征垃圾渗滤液处理过程中有机物的特性变化,分别采用紫外光谱和三维荧光光谱对2种垃圾渗滤液处理工艺不同单元溶解性有机物(DOM)的变化进行了系统分析。结果表明,二级RO和厌氧+好氧+MBR+NF+RO工艺对渗滤液COD和NH3-N的去除率分别为98.7%、99.0%和98.8%、98.6%。随着处理过程的进行,2个处理工艺中DOM的SUVA254、E253/E203分别由0.74、0.33和0.46、0.12下降至0.015、0.014和0.010、0.012,有机物的芳香性和不饱和性下降,脂肪链芳香烃化合物开始增加。不同处理阶段渗透液DOM三维荧光光谱表明,随着处理过程的进行,类富里酸和类蛋白物质的含量逐渐下降,芳构化程度开始降低。其中二级RO系统对渗滤液中类富里酸物质的去除效果较好,而厌氧-好氧-MBR-NF-RO工艺中,类酪氨酸物质主要通过微生物降解去除,NF和RO膜对类富里酸和类腐殖酸物质的截留效果较好。     

Spatial variability in chromophoric dissolved organic matter for an artificial coastal lake (Shiwha) and the upstream catchments at two different seasons

Selected water quality parameters and spectroscopic characteristics of dissolved organic matter (DOM) were examined during two different seasons for an artificial coastal lake (Shiwha Lake in South Korea), which are affected by seawater exchange due to the operation of a tidal power plant and external organic loadings from the upstream catchments. The coastal lake exhibited much lower concentrations of organic matter and nutrients than the upstream sources. The spectroscopic properties of the lake DOM were easily distinguished from those of the catchment sources as revealed by a lower absorption coefficient, lower degree of humification, and higher spectral slopes. The observed DOM properties suggest that the lake DOM may be dominated by smaller molecular size and less condensed structures. For the lake and the upper streams, higher absorption coefficients and fluorescence peak intensities but lower spectral slopes and humification index were found for the premonsoon versus the monsoon season. However, such seasonal differences were less pronounced for the industrial channels in the upper catchments. Three distinctive fluorophore groups including microbial humic-like, tryptophan-like, and terrestrial humic-like fluorescence were decomposed from the fluorescence excitation-emission matrix (EEM) of the DOM samples by parallel factor analysis (PARAFAC) modeling. The microbial humic-like component was the most abundant for the industrial channels, suggesting that the component may be associated with anthropogenic organic pollution. The terrestrial humic-like component was predominant for the upper streams, and its relative abundance was higher for the rainy season. Our principal component analysis (PCA) results demonstrated that exchange of seawater and seasonally variable input of allochthonous DOM plays important roles in determining the characteristics of DOM in the lake.     

Fluorescence spectroscopic characterization of DOM fractions isolated from a filtered river water after ozonation and catalytic ozonation

Fluorescence spectra were applied to investigate the structural changes of four dominant dissolved natural organic matter (DOM) fractions of a filtered river water before and after ozonation and catalytic ozonation. The ozonation and catalytic ozonation with synthetic goethite (FeOOH) and cerium dioxide (CeO(2)) were carried out under normal conditions, i.e. pH 7, reaction time of 10 min, and ozone/DOC ratio of about 1. The fluorescence spectra were recorded at both excitation-emission matrix (EEM) and synchronous scanning modes. EEM results reveal that ozonation of these DOM fractions causes a significant decrease of the aromaticity of humic-like structures and an increase of electron withdrawing groups, e.g., carboxylic groups. The catalysts can further improve the destruction of the humic-like structures in catalytic ozonation. Synchronous spectra reveal that ozonation of hydrophobic acid and hydrophilic acid (HIA) yields a significant amount of by-products with low aromaticity and low molecular weight. Catalytic ozonation enhances substantially the formation of these by-products from HIA and improves the destruction of highly polycyclic aromatic structures for all examined DOM fractions.     

Microbial transformation of dissolved organic matter from different sources and its influence on disinfection byproduct formation potentials

Biodegradation-induced changes in the characteristics of dissolved organic matter (DOM) and the subsequent effects on disinfection byproduct formation potentials (DBPFPs) were investigated using six different sources of DOM (algae, leaf litter, reed, compost, paddy water, and treated municipal sewage effluent). Microbial incubation of the DOM samples increased the specific ultraviolet absorbance and humic-like fluorescence but decreased the protein/tannin-like fluorescence and relative distribution of smaller-sized DOM components. Comparison of the original versus biodegraded DOM samples using resin fractionation and pyrolysis–gas chromatography/mass spectrometry revealed that the biodegradation-induced changes were highly dependent on DOM sources and exhibited no consistent trends among the different sources. Changes in DBPFPs also differed with DOM source. Vascular plant-derived DOM (leaf litter and reed) demonstrated an enhancement in specific DBPFP after biodegradation, whereas little change or even a slight decrease was observed for the other DOM sources. Correlations that were significant between specific DBPFPs and the aromatic content or humic-like fluorescence for the original DOM samples were no longer significant after microbial degradation. The relative abundance of hydrophobic to hydrophilic structures in DOM is suggested to be a general indicator for the formation potential of trihalomethanes irrespective of DOM source and the state of biodegradation.