活性炭吸附受污染河水中有机物的三维荧光分析

采用活性炭吸附净化受污染河水,考察了不同吸附时间及投量下的净化效果,同时结合三维荧光光谱(EEM)技术探讨了河水中溶解性有机质(DOM)组分的变化.结果表明,宋梁路段河水中的有机物含量较高,DOM主要为类腐殖酸、类富里酸和芳香族蛋白质类化合物;河水的EEM中主要存在3个荧光峰和1个荧光峰带;活性炭对类腐殖酸和类富里酸的吸附效果较好,对芳香族蛋白质的吸附效果较差,最佳吸附时间为15 min.甘棠段河水的EEM中有2个荧光峰A和B(均为色氨酸类蛋白质)及1个峰带C(与类腐殖酸有关);活性炭最佳投量为0.5 mg/mL,此时峰带C消失,A峰和B峰强度变化率分别达到了81.31%和92.52%.     

辽东湾海域有色可溶性有机物荧光特征分析

为了分析辽东湾有色可溶性有机物(Chromophoric dissolved organic matter,CDOM)的分布特征,于2015年4月14日—5月3日采用"走航式"测量方法,分别获取了辽东湾海域32个站位表层、5、10 m 3个不同深度水层的CDOM荧光图谱、吸收系数和石油物质含量等数据。结果表明:表层(0 m)CDOM的荧光图谱分为3种类型:单峰型、双峰型和三峰型,5、10 m深水层CDOM的荧光图谱主要为单峰型和双峰型;3种峰型均包含位于激发波长(Ex)/发射波长(Em)为225~235 nm/325~350 nm的荧光峰,这主要是海水浮游植物自身降解产生的色氨酸产生的;在靠近海上油气开采平台和双台子河入海口的海域,油物质和CDOM的共同作用,使得位于这些区域的站点表层的荧光强度明显增强,荧光峰的范围也有所增大;表层、10 m深水层荧光强度最大值和最小值随站位的走势基本一致,而5 m深水层的走势就比较复杂;无论是哪种类型的荧光峰,其位置随着水深的增加基本保持不变,荧光强度随水深变化规律不明显。本研究中建立的由荧光峰强度(Af)和CDOM在440 nm处吸收系数[ag(440)]的比值来求解光谱斜率(S)的模型,可为利用荧光和可见光遥感技术反演光谱斜率S提供一种新方法。     

辽东湾海域有色可溶性有机物荧光特征分析

为了分析辽东湾有色可溶性有机物(Chromophoric dissolved organic matter,CDOM)的分布特征,于2015年4月14日—5月3日采用"走航式"测量方法,分别获取了辽东湾海域32个站位表层、5、10 m 3个不同深度水层的CDOM荧光图谱、吸收系数和石油物质含量等数据。结果表明:表层(0 m)CDOM的荧光图谱分为3种类型:单峰型、双峰型和三峰型,5、10 m深水层CDOM的荧光图谱主要为单峰型和双峰型;3种峰型均包含位于激发波长(Ex)/发射波长(Em)为225²35 nm/325235 nm/325³50 nm的荧光峰,这主要是海水浮游植物自身降解产生的色氨酸产生的;在靠近海上油气开采平台和双台子河入海口的海域,油物质和CDOM的共同作用,使得位于这些区域的站点表层的荧光强度明显增强,荧光峰的范围也有所增大;表层、10 m深水层荧光强度最大值和最小值随站位的走势基本一致,而5 m深水层的走势就比较复杂;无论是哪种类型的荧光峰,其位置随着水深的增加基本保持不变,荧光强度随水深变化规律不明显。本研究中建立的由荧光峰强度(Af)和CDOM在440 nm处吸收系数[ag(440)]的比值来求解光谱斜率(S)的模型,可为利用荧光和可见光遥感技术反演光谱斜率S提供一种新方法。     

基于光谱法解析污水厂DOM转化与DBPs生成特征

通过检测污水处理厂进、出水以及各处理单元出水的理化指标,结合三维荧光光谱和紫外光谱特征,对污水处理厂中溶解性有机物(DOM)的迁移转化进行解析。结果表明,应用荧光区域积分法与平行因子分析法识别出污水中的2个特征荧光组分为类色氨酸(C1,275 nm/330 nm)和类富里酸(C2,290 nm/420 nm),在污水厂全流程处理工艺中,C1下降了85%、C2下降了50%;荧光组分与常规水质指标COD、BOD₅、TOC以及UV₂₅₄等均呈极显著正相关。加氯消毒后DOM的荧光特征峰出现蓝移,在出水中检测到的消毒副产物(DBPs)主要为三氯甲烷、二氯乙酸和三氯乙酸,浓度分别为16.3、19.0和23.8μg/L,应受到关注。     

城市污水处理厂泥区废液水质特性分析

采用常规水质分析方法、三维荧光光谱分析方法、超滤分子质量分级分析方法以及色谱法,对3座典型城市污水处理厂的泥区废液水质特性进行了调查分析。结果表明,泥区废液污染物的负荷较高,其水质状况与污水、污泥处理工艺及其运行工况有关。泥区废液中的主要有机污染物种类有类蛋白质、类富里酸及类腐殖酸,各类物质的含量与污泥稳定程度有关,浓缩池上清液和未经消化的污泥脱水滤液以类蛋白质为主,污泥消化后的脱水滤液以类富里酸或类腐殖酸为主。泥区混合废液中表观分子质量〉6ku的有机物所占比例〉70％,泥区废液中内分泌干扰物质壬基酚及其前体物质壬基酚聚氧乙烯醚含量约为1．35～23．01μg／L。     

前处理工艺对炼化污水污染物组成特性的影响

文章以某炼化企业双膜工艺RO装置前各工艺段出水为研究对象,对其进行综合水质特性分析,并采用三维荧光光谱（3D-EEM）、紫外—可见（UV-Vis）光谱和傅里叶红外光谱（FTIR）分析比较污水中的有机物组成及特性。结果表明：炼化污水中溶解性有机物（DOM）是污水化学需氧量（COD）的主要来源,DOM的分子量和芳香度随着处理工艺的进行逐渐降低。生物接触氧化、絮凝—气浮和砂滤工艺在一定程度上增加了DOM的含量,而超滤（UF）出水具有最低的溶解性有机碳（DOC）。3D-EEM光谱表明：炼化污水中DOM主要含有腐殖酸类腐殖质、微生物代谢产物和芳香类蛋白质3类荧光物质,生物接触氧化工艺能够显著增加DOM中微生物代谢产物和芳香类蛋白质的含量。FTIR光谱分析表明：在各工艺段出水中,UF出水DOM中含有更多的脂肪类有机物、C＝O官能团而非C＝C和C—O结构。     

高碳氮废水处理中有机物的荧光光谱特征分析

采用三维荧光光谱技术考察某厂高碳氮废水中有机物的荧光光谱特征及荧光强度与COD去除效果和氨氮浓度变化的关系。反应器稳定运行后进出水COD分别为5 500和1 510mg/L,对COD的去除率达到72.5%,氨氮浓度增加了40.6%,总氮浓度基本保持不变。通过荧光光谱分析,废水中的有机物主要由类蛋白质和类腐殖酸组成,荧光峰中心位置分别为Ex/Em=275/355 nm和Ex/Em=330/425 nm;蛋白质荧光强度从4 175减少至1 318,其与周期内COD去除率、氨氮浓度均存在较好的线性相关性,R2分别为0.943和0.965。说明可以通过荧光光谱技术定性表征生物处理废水过程中有机物的转化情况及其与碳、氮变化的关系。     

低C/N污水处理过程中有机碳源的特性及转化分析

C/N值是影响污水脱氮效果的主要因素之一,为探究低C/N值城镇污水处理过程中不同特性有机碳源的利用水平,采用三维荧光光谱-平行因子分析技术（3DEEM-PARAFAC）,对广东省某污水厂SBR工艺不同处理阶段的水质进行分析。结果表明,3DEEM-PARAFAC技术可有效表征低C/N污水处理过程中有机碳源的特征变化,并解析出4种荧光组分：类色氨酸、氨基酸、腐殖酸类和富里酸类。其中,类色氨酸和氨基酸占比较高,属于易生物降解碳源;腐殖酸类和富里酸类占比较低,属于难生物降解碳源。相关性分析表明,4种荧光组分与COD、TP、NH4+-N和TN指标之间存在显著相关性（p<0.05）,其中氨基酸呈现出最显著相关性,是影响脱氮效果的关键物质。     

城镇污水处理厂尾水中氮磷形态及光谱特征分析

为了进一步探究污水厂尾水排放对受纳水体的潜在影响,选取巢湖流域采用3种典型处理工艺(氧化沟、SBR、A²/O工艺)的7座污水厂为研究对象,分析了尾水中氮、磷的形态及水体中溶解性有机质(DOM)的光谱特征。结果表明,不同工艺对TN、TP、COD等指标均具有很好的去除效果且无明显差异。尾水中颗粒态总氮(PN)占比在13.4%以下,主要以溶解态总氮(DTN)形式存在,其中溶解态无机氮(DIN)占比高于溶解态有机氮(DON)。尾水中颗粒态总磷(PP)占比在10.1%~66.7%,磷主要以溶解态总磷(DTP)形式存在,其中溶解态无机磷(DIP)占比在60%以上。DOM的三维荧光光谱显示,不同工艺尾水中的DOM均具有4类荧光特征峰,其中腐殖酸类物质C峰与紫外区类富里酸物质A峰较为明显。根据DOM的荧光特性参数(HIX值<4、FI值>1.9、BIX值>1.0),各污水厂出水中的DOM主要为自生来源。由此表明,污水处理厂削减了大量的入河碳、氮、磷等负荷,其尾水可用于城市河道生态补水水源,实现城市污水资源再生利用。     

提高波长色散X荧光光谱仪晶体衍射强度的方法

波长色散X荧光光谱仪是检验物质化学成份的传统工具,在各个行业中的应用非常广泛。但是由于晶体衍射强度不够高等问题,一直使波长色散X荧光光谱仪在低含量低原子序数元素的分析方面受到一定的限制。本文全面介绍了近年来以加强晶体衍射强度为目的的新技术,例如全聚焦、半聚焦、对数螺线柱面弯曲晶体衍射技术,和双曲面晶体衍射技术及大面积晶体阵列技术。这些新技术新工艺的出现,使波长色散X荧光光谱仪在低含量低原子序数元素分析性能上有了长足的进步。     

Characterization of dissolved organic matter in a submerged membrane bioreactor by using three-dimensional excitation and emission matrix fluorescence spectroscopy

Three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy was employed to characterize dissolved organic matter (DOM) in a submerged membrane bioreactor (MBR). Three fluorescence peaks could be identified from the EEM fluorescence spectra of the DOM samples in the MBR. Two peaks were associated with the protein-like fluorophores, and the third was related to the visible humic acid-like fluorophores. Only two main peaks were observed in the EEM fluorescence spectra of the extracellular polymeric substance (EPS) samples, which were due to the fluorescence of protein-like and humic acid-like matters, respectively. However, the EEM fluorescence spectra of membrane foulants were observed to have three peaks. It was also found that the dominant fluorescence substances in membrane foulants were protein-like substances, which might be due to the retention of proteins in the DOM and/or EPS in the MBR by the fine pores of the membrane. Quantitative analysis of the fluorescence spectra including peak locations, fluorescence intensity, and different peak intensity ratios and the fluorescence regional integration (FRI) analysis were also carried out in order to better understand the similarities and differences among the EEM spectra of the DOM, EPS, and membrane foulant samples and to further provide an insight into membrane fouling caused by the fluorescence substances in the DOM in submerged MBRs.     

Thermal fluorescence quenching properties of dissolved organic matter

The fluorescence excitation-emission matrices of dissolved organic matter (DOM) are investigated between 10 and 45 degrees C for river and waste waters and organic matter standards. With increased temperature, fluorescence intensity is quenched. It is demonstrated that for a range of river and wastewater samples, that tryptophan-like fluorescence exhibits a greater range of quenching (between 20+/-4% and 35+/-5%) than fulvic-like fluorescence (19+/-4 to 26+/-3%) over this temperature range. Humic substance standards exhibit similar fulvic-like (23+/-4%) fluorescence thermal quenching properties to river water samples (23+/-3%); however none of the samples exhibit quenching of tryptophan-like fluorescence to the same extent as the tryptophan standards (approximately 50%). Thermal fluorescence quenching is related to the exposure of the fluorophores to the heat source; our findings suggest that the tryptophan-like groups within DOM is more exposed in untreated wastewaters than in treated wastewaters riverine DOM. Thermal fluorescence properties have the potential to be used to source DOM, to provide additional chemical structural information, to temperature correct laser-induced remotely sensed DOM fluorescence, and to characterise DOM through the wastewater treatment process.     

Characterization of DOM as a function of MW by fluorescence EEM and HPLC-SEC using UVA,DOC, and fluorescence detection

To investigate the composition of dissolved organic matter (DOM) as a function of apparent molecular weight (MW) by rapid analytical methods, high performance liquid chromatography (HPLC)-size exclusion chromatography (SEC) was conducted with sequential on-line detectors consisting of UV, fluorescence, and quantitative DOC measurement. Fluorescence excitation-emission matrix (EEM) spectrophotometry was used to select wavelengths for the HPSEC on-line fluorescence system. The chosen peak maxima locations of excitation-emission wavelengths were 278-353 nm for protein-like substances and 337-423 nm for fulvic-like substances based on an analysis of EEM spectra for various samples and reference materials. This system provides quantitative and qualitative information on the specific MW components of DOM, including proportion of DOC (by DOC measurement), aromaticity (by comparison of UV and DOC measurements), and chemical properties (by fluorescence measurement). It further allows determination of organic matter characteristics (e.g., fulvic-like, protein-like, and polysaccharide-like substances) as a function of MW. Three types of samples (Irvine Ranch ground water (IRWD-GW), Barr Lake surface water (BL-SW), and Hawaii wastewater secondary effluent) were analyzed by the HPSEC-UVA-fluorescence-DOC system. These results were compared with fluorescence EEM for samples fractionated by HPLC-SEC. The DOM fraction in the high apparent MW range (over 10,000g/mol) consisted of polysaccharide-like substances for IRWD-GW and a mixture of polysaccharide-like/protein-like substances for BL-SW and wastewater secondary effluent. Minimal amounts of fulvic-like substances were found in the wastewater secondary effluent sample. The DOM fractions in a medium apparent MW range (5000-1000 g/M) showed higher aromaticity (fulvic in character) than any other fractions for all samples. For the DOM fraction in the low apparent MW range (below 680 g/M), additional aliphatic organic matter was found in IRWD-GW, while BL-SW contained protein-like processes. DOM plays an important role in drinking water and wastewater treatment processes. An enhanced HPSEC technique with multiple on-line detectors enables a better understanding of quantitative and qualitative DOM properties and can help to design and optimize water/wastewater treatment facilities.     

Characterization of extracellular polymeric substances of aerobic and anaerobic sludge using three-dimensional excitation and emission matrix fluorescence spectroscopy

In this study three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy was applied to characterize the extracellular polymeric substances (EPS) extracted from aerobic and anaerobic sludge in wastewater treatment. Three fluorescence peaks were identified in EEM fluorescence spectra of the EPS samples. Two peaks were attributed to the protein-like fluorophores, and the third to the humic-like fluorophores. The effects of both pH and EPS concentration were significant on EEM fluorescence spectra of EPS, but the ionic strength had no substantial effect on EEM spectra of the EPS. The differences in the EPS fluorescence parameters, e.g., peak locations, intensities and ratios of various peak intensities, indicate the difference in the chemical structures of the EPS from various origins. EEM spectroscopy was proven to be an appropriate and effective method to characterize the EPS from various origins in wastewater treatment systems.     

Characterization of organic membrane foulants in a submerged membrane bioreactor with pre-ozonation using three-dimensional excitation-emission matrix fluorescence spectroscopy

This study focuses on organic membrane foulants in a submerged membrane bioreactor (MBR) process with pre-ozonation compared to an individual MBR using three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy. While the influent was continuously ozonated at a normal dosage, preferable organic matter removal was achieved in subsequent MBR, and trans-membrane pressure increased at a much lower rate than that of the individual MBR. EEM fluorescence spectroscopy was employed to characterize the dissolved organic matter (DOM) samples, extracellular polymeric substance (EPS) samples and membrane foulants. Four main peaks could be identified from the EEM fluorescence spectra of the DOM samples in both MBRs. Two peaks were associated with the protein-like fluorophores, and the other ones were related to the humic-like fluorophores. The results indicated that pre-ozonation decreased fluorescence intensities of all peaks in the EEM spectra of influent DOM especially for protein-like substances and caused red shifts of all fluorescence peaks to different extents. The peak intensities of the protein-like substances represented by Peak T₁ and T₂ in EPS spectra were obviously decreased as a result of pre-ozonation. Both external and internal fouling could be effectively mitigated by the pre-ozonation. The most primary component of external foulants was humic acid-like substance (Peak C) in the MBR with pre-ozonation and protein-like substance (Peak T₁) in the individual MBR, respectively. The content decrease of protein-like substances and structural change of humic-like substances were observed in external foulants from EEM fluorescence spectra due to pre-ozonation. However, it could be seen that ozonation resulted in significant reduction of intensities but little location shift of all peaks in EEM fluorescence spectra of internal foulants.     

Dissolved organic matter in leachate from different treatment processes

The main objectives of this study were to investigate the characteristics of dissolved organic matter (DOM) extracted from the leachate of different treatment process using the chemical and spectroscopic analysing methods. The humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) were isolated and purified by the XAD-8 resin combined with the cation exchange resin method. The analytical results of fluorescence excitation-emission matrix spectroscopy (EEMs) revealed that the fluorescence peaks were protein-like fluorescence for equalization basin and discharge of reverse osmosis (RO), while the fluorescence peaks for second sedimentation tank were humic-like and fulvic-like fluorescence. Moreover, the results also showed that protein-like organic matter are readily removed by biological process and HA and FA can be removed by RO process. Elemental analysis indicated that the nitrogen content in these isolated fractions followed: HA>HyI>FA. The information on the characteristics of DOM indicated important role in optimization of leachate treatment processes.     

Rapid and direct determination of tryptophan in water using synchronous fluorescence spectroscopy

Water samples from lakes situated in and around the area of Tsukuba Science City, Ibaraki Prefecture, Japan, were analysed using synchronous fluorescence spectroscopy and HPLC. The spectra revealed a major emission peak (lambda emm) at 340 nm corresponding to an excitation wavelength (lambda exc) position of 280 nm and a Stoke's shift, delta lambda = 60 nm. The fluorescence intensities at these wavelengths were normalised with respect to the water Raman peak, where the lambda exc was 397 nm and the lambda emm was 453 nm, and corrections were introduced to take into account absorption/re-absorption effects of the fluorescing signals caused by the sample matrix. Normalised fluorescence values correlate well with levels of tryptophan present in the samples determined by HPLC analysis (R2 = 0.99). The relationship of the observed tryptophan-like fluorescence in the water samples to the presence of free tryptophan is discussed.     

Measurement of protein-like fluorescence in river and waste water using a handheld spectrophotometer

Protein-like fluorescence intensity in rivers increases with increasing anthropogenic DOM inputs from sewerage and farm wastes. Here, a portable luminescence spectrophotometer was used to investigate if this technology could be used to provide both field scientists with a rapid pollution monitoring tool and process control engineers with a portable waste water monitoring device, through the measurement of river and waste water tryptophan-like fluorescence from a range of rivers in NE England and from effluents from within two waste water treatment plants. The portable spectrophotometer determined that waste waters and sewerage effluents had the highest tryptophan-like fluorescence intensity, urban streams had an intermediate tryptophan-like fluorescence intensity, and the upstream river samples of good water quality the lowest tryptophan-like fluorescence intensity. Replicate samples demonstrated that fluorescence intensity is reproducible to +/- 20% for low fluorescence, 'clean' river water samples and +/- 5% for urban water and waste waters. Correlations between fluorescence measured by the portable spectrophotometer with a conventional bench machine were 0.91; (Spearman's rho, n = 143), demonstrating that the portable spectrophotometer does correlate with tryptophan-like fluorescence intensity measured using the bench spectrophotometer.     

三维荧光技术用于给水的水质测定

采用三维荧光分析技术分类研究了原水中可溶解性有机物在传统水处理工艺中的去除过程。结果表明,三维荧光分析方法能够将原水中有机物区分成不同类型的腐殖酸和蛋白质,并揭示其在传统水处理工艺中去除效率的变化,而且三维荧光数据与COD、DOC和UV254等水质指标存在着良好的相关性。