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Prediction of DOM removal of low specific UV absorbance surface waters using HPSEC combined with peak fitting

Journal of Environmental Sciences 2012年第7期24卷 1174-1180页

作者： Linan Xing Rolando Fabris W.K.Chow john van leeuwen Mary Drikas Dongsheng Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of ScinecesBeijing 100085China Australian Water Quality Centre South Australian Water Corporation256 Victoria SquareAdelaideSouth Australia 5000Australia SA Water Centre for Water Management and Reuse University of South AustraliaMawson LakesSouth Australia 5095Australia

High performance size exclusion chromatography （HPSEC） is used in water quality research primarily to determine the molecular weight distribution of the dissolved organic matter （DOM）, but by applying peak fitting to the chromatogram, this technique can also be used as a tool to model and predict DOM removal. Six low specific UV absorbance （SUVA） source waters were treated using coagulation with alum and both the source and treated water samples were analysed using HPSEC. By comparing the molecular weight profiles of the source and treated waters, it was established that several DOM components were not effectively removed by alum coagulation even after high dosage alum treatment. A peak-fitting technique was applied based on the concept of linking the character （molecular weight profile） of the recalcitrant organics in the treated water with those of the source water. This was then applied to predict DOM treatability by determining the areas of the peaks which were assigned to removable organics from the source water molecular weight profile after peak fitting, and this technique quantified the removable and non-removable organics. The prediction was compared with the actual dissolved organic carbon （DOC） removal determined from jar testing and showed good agreement, with variance between 2% and 10%. This confirmed that this prediction approach, which was originally developed for high SUVA waters, can also be applied successfully to predict DOC removal in low SUVA waters.

关键词： DOM high performance size exclusion chromatography peak fitting water treatment

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Changes in the quality of river water before,during and after a major flood event associated with a La Nina cycle and treatment for drinking purposes

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Journal of Environmental Sciences 2014年第10期26卷 1985-1993页

作者： Mohamad Fared Murshed Zeeshan Aslam Rosmala Lewis Christopher Chow Dongsheng Wang Mary Drikas john van leeuwen Centre for Water Management and Reuse Natural and Built Environments University of South Australia Australian Water Quality Centre South Australian Water Corporation State Key Laboratory for Environmental Aquatic Chemistry Research Centre for Eco-Environmental Sciences Barbara Hardy Institute Natural and Built EnvironmentsUniversity of South Australia

The treatment of organics present in the lower reaches of a major river system（the Murray–Darling Basin, Australia） before（March–July 2010）, during（December 2010–May 2011） and after（April–December 2012） a major flood period was investigated. The flood period（over 6 months）occurred during an intense La Nia cycle, leading to rapid and high increases in river flows and organic loads in the river water. Dissolved organic carbon（DOC） increased（2–3 times） to high concentrations（up to 16 mg/L） and was found to correlate with river flow rates. The treatability of organics was studied using conventional jar tests with alum and an enhanced coagulation model（mEnCo）. Predicted mean alum dose rates（per mg DOC） were higher before（9.1 mg alum/mg DOC） and after（8.5 mg alum/mg DOC） than during the flood event（8.0 mg alum/mg DOC）,indicating differences in the character of the organics in raw waters. To assess the character of natural organic matter present in raw and treated waters, high performance size exclusion chromatography with UV and fluorescence detectors were used. During the flood period, high molecular weight UV absorbing compounds（〉2 kDa） were mostly detected in waters collected,but were not evident in waters collected before and afterwards. The relative abundances of humic-like and protein-like compounds during and following the flood period were also investigated and found to be of a higher molecular weight during the flood period. The treatability of the organics was found to vary over the three climate conditions investigated.

关键词： Alum Coagulation Flood mEnCo prediction dose(EnCD) La Ni?a

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A novel mathematical template for developing fDOM probe fluorescence signal correction models for freshwaters

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Journal of Environmental Sciences 2024年第12期146卷 103-117页

作者： Hiua Daraei Edoardo Bertone john Awad Rodney A.Stewart Christopher W.K.Chow Jinming Duan Amanda Mussared john van leeuwen Sustainable Infrastructure and Resource Management(SIRM) UniSA STEMUniversity of South AustraliaMawson LakesSA 5095Australia Griffith School of Engineering and Built Environment Griffith UniversityQueensland 4222Australia Cities Research Institute Griffith UniversityParklands DriveSouthportQueensland 4222Australia CSIRO Environment AdelaideSA 5000Australia Australian Water Quality Centre SA Water250 Victoria SquareAdelaideSA 5000Australia Australian Rivers Institute Griffith University170 Kessels RoadNathanQueensland 4111Australia Environmental Health Research Centre Kurdistan University of Medical SciencesSanandajKurdistanIran

The reliable application of field deployable fluorescent dissolved organic matter(fDOM)probes is hindered by several influencing factors which need to be *** manuscript describes the corrections of temperature,pH,turbidity and inner filter effect on fluorescence signal of a commercial fDOM probe(fDOMs).For this,Australian waters with wide ranging qualities were selected,*** organic carbon(DOC)ranging from∼1 to∼30 mg/L,specific UV absorbance at 254 nm from∼1 to∼6 L/m/mg and turbidity from∼1 to∼350 ***-based model calibration experiments(MCEs)were performed.A model template was developed and used for the development of the correction *** each factor,data generated through MCEs were used to determine model coefficient(α)values by fitting the generated model to the experimental *** discrete factor models were generated by determination of a factor-specificα***αvalues derived for each water of the MCEs subset were consistent for each factor *** indicated generic nature of the fourαvalues across wide-ranging water *** correlation between fDOMs and DOC were achieved after applying the four-factor compensation models to new data(r,0.96,p<0.05).Also,average biases(and%)between DOC predicted through fDOMs and actual DOC were decreased by applying the four-factor compensationmodel(from3.54(60.9%)to 1.28(16.7%)mg/L DOC).These correction models were incorporated into a Mi-crosoft EXCEL-based software termed EXOf-Correct for ready-to-use applications.

关键词： Surface waters Online monitoring fDOM probes Fluorescence signal Model-based corrections

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pH modeling for maximum dissolved organic matter removal by enhanced coagulation

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Journal of Environmental Sciences 2012年第2期24卷 276-283页

作者： Jiankun Xie Dongsheng Wang john van leeuwen Yanmei Zhao Linan Xing Christopher W. K. Chow State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China SA Water Centre for Water Management and Reuse NBE Universit of South Australia Australia Australian Water Quality Centre SA Water 250 Victoria Square Adelaide SA 5000 Australia

Correlations between raw water characteristics and pH after enhanced coagulation to maximize dissolved organic matter（DOM） removal using four typical coagulants（FeCl3,Al2（SO4）3,polyaluminum chloride（PACl） and high performance polyaluminum chloride（HPAC）） without pH control were *** correlations were analyzed on the basis of the raw water quality and the chemical and physical fractionations of DOM of thirteen Chinese source waters over three *** was found that the final pH after enhanced coagulation for each of the four coagulants was in？uenced by the content of removable DOM（*** and higher apparent molecular weight（AMW） DOM）,the alkalinity and the initial pH of raw water.A set of feed-forward semi-empirical models relating the final pH after enhanced coagulation for each of the four coagulants with the raw water characteristics were developed and optimized based on correlation *** established models were preliminarily validated for prediction purposes,and it was found that the deviation between the predicted data and actual data was *** result demonstrated the potential for the application of these models in practical operation of drinking water treatment plants.

关键词： enhanced coagulation modeling DOM fractionation pH control

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Influence of coagulation mechanisms and floc formation on filterability

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Journal of Environmental Sciences 2017年第7期29卷 338-345页

作者： Ruyuan Jiao Rolando Fabris Christopher W.K.Chow Mary Drikas john van leeuwen Dongsheng Wang Zhizhen Xu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences Australian Water Quality Centre South Australian Water Corporation Centre for Water Management and Reuse School of Natural and Built EnvironmentsUniversity of South Australia Key Laboratory of Occupational Safety and Health Beijing Municipal Institute of Labor Protection

Minimizing particles in water is a key goal for improving drinking water quality and *** media filtration process,as the last step of the solid–liquid separation process,is largely influenced by the characteristics of flocs,which are formed and controlled within the coagulation *** a laboratory-based study,the impacts of the physical characteristics of flocs formed using aluminum sulfate on the filtration treatment of two comparative water samples were investigated using a photometric dispersion analyzer and a filterability *** general,the optimum dosage for maximizing filterability was higher than that for minimizing turbidity under neutral p H *** a monomeric aluminum-based coagulant,the charge neutralization mechanism produced better floc characteristics,including floc growth speed and size,than the sweep flocculation *** addition,the charge neutralization mechanism showed better performance compared to sweep flocculation in terms of DOC removal and floc filterability improvement for both waters,and showed superiority in turbidity removal only when the raw water had high *** the different mechanisms,the ways that floc characteristics impacted on floc filterability also *** low variation in floc size distribution obtained under the charge neutralization mechanism resulted in the flocs being amenable to removal by filtration *** the sweep flocculation mechanism,increasing the floc size improved the settling ability of flocs,resulting in higher filter efficiency.

关键词： Coagulation mechanisms Floc characteristics Filterability Turbidity

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Chloramine demand estimation using surrogate chemical and microbiological parameters

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Journal of Environmental Sciences 2017年第7期29卷 1-7页

作者： Sina Moradi Sanly Liu Christopher W.K.Chow john van leeuwen David Cook Mary Drikas Rose Amal School of Chemical Engineering The University of New South Wales Australian Water Quality Centre SA Water Corporation Centre for Water Management and Reuse School of Natural and Built EnvironmentsUniversity of South Australia

A model is developed to enable estimation of chloramine demand in full scale drinking water supplies based on chemical and microbiological factors that affect chloramine decay rate via nonlinear regression analysis *** model is based on organic character（specific ultraviolet absorbance（SUVA）） of the water samples and a laboratory measure of the microbiological（Fm） decay of *** applicability of the model for estimation of chloramine residual（and hence chloramine demand） was tested on several waters from different water treatment plants in Australia through statistical test analysis between the experimental and predicted *** showed that the model was able to simulate and estimate chloramine demand at various times in real drinking water *** elucidate the loss of chloramine over the wide variation of water quality used in this study,the model incorporates both the fast and slow chloramine decay *** significance of estimated fast and slow decay rate constants as the kinetic parameters of the model for three water sources in Australia was *** was found that with the same water source,the kinetic parameters remain the *** modelling approach has the potential to be used by water treatment operators as a decision support tool in order to manage chloramine disinfection.

关键词： Chloramine demand Drinking water treatment plants Modelling

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Developing a chloramine decay index to understand nitrification:A case study of two chloraminated drinking water distribution systems

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Journal of Environmental Sciences 2017年第7期29卷 170-179页

The management of chloramine decay and the prevention of nitrification are some of the critical issues faced by water utilities that use chloramine as a *** this study,potential association between high performance size exclusion chromatography（HPSEC）data obtained with multiple wavelength Ultraviolet（UV） detection from two drinking water distribution systems in Australia and nitrification occurrence was *** increase in the absorbance signal of HPSEC profiles with UV detection at λ = 230 nm between apparent molecular weights of 200 to 1000 Da was observed at sampling sites that experienced rapid chloramine decay and nitrification while its absorbance signal at λ =254 nm decreased.A chloramine decay index（C.D.I） defined as the ratio of area beneath the HPSEC spectra at two different wavelengths of 230 and 254 nm,was used in assessing chloramine decay *** *** of waters at locations that experienced nitrification were consistently higher than locations not experiencing nitrification.A simulated laboratory study showed that the formation of nitrite/nitrate and/or soluble microbial products and/or the release of extracellular polymeric substances（EPS） during nitrification may contribute to the *** findings suggest that C.D.I derived from HPSEC with multiple wavelength UV detection could be an informative index to track the occurrence of rapid chloramine decay and nitrification.

关键词： HPSEC Water distribution systems Nitrification Chloramine decay

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以热机械浆和旧报纸/旧杂志纸为原料的新闻纸厂活性污泥菌胶团的黏性膨胀

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中国造纸 2015年第4期 76-76页

作者： STEVEN NOTHROP DES RICHARDSON john van leeuwen MICHAEL MACHIN KOBUS THEUNISSEN TROY WATKINS BEN van DEN AKKER

在这项研究中,我们发现发生在一家新闻纸厂活性污泥废水处理厂的污泥膨胀是由菌胶团黏性膨胀(或水合膨胀)所导致的。在挪威诺斯克公司Albury工厂的活性污泥厂(ASP),菌胶团黏性膨胀表现为显微镜下的无定形团块,它在二次澄清过程中在曝气... 详细信息

在这项研究中,我们发现发生在一家新闻纸厂活性污泥废水处理厂的污泥膨胀是由菌胶团黏性膨胀(或水合膨胀)所导致的。在挪威诺斯克公司Albury工厂的活性污泥厂(ASP),菌胶团黏性膨胀表现为显微镜下的无定形团块,它在二次澄清过程中在曝气池的废水表面形成硬壳,同时在曝气池生成大量泡沫。使用亚甲蓝染色法确认了能引起发泡的多糖/胞外聚合物类物质(EPS)产生,另外(污泥)絮状物比较分散并且呈淡蓝色。这一条件导致大量的白色泡沫,对活性污泥的沉降性能和脱水性能产生了不利影响。菌胶团黏性膨胀可以通过以下方面进行控制:减少营养物/微生物(F/M)的比例;维持宏观养分(正磷酸盐和氨;磷和氮)的残余浓度;通过在好氧选择器后添加厌氧选择器和/或在好氧选择器前减少缺氧程度来控制微生物增长率等。在活性污泥厂,当进入选择器1的化学耗氧度的F/M比例为20∶1时,菌胶团膨胀非常严重。通过使用缺氧选择器2并在两个曝气池中保持适当的铵和正磷酸盐的浓度来控制菌胶团的生长速率成功地控制EPS的产生。在此情况下,使用亚甲蓝染色法观测到的絮状物呈现紧实特性(深蓝色和低多糖)。消泡剂的用量也减少了90%。

关键词：菌胶团黏性膨胀增长速度缺氧选择器生物可利用的营养物质胞外聚合物

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Effect of competing solutes on arsenic(Ⅴ) adsorption using iron and aluminum oxides

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Journal of Environmental Sciences 2007年第8期19卷 910-919页

作者： Youngran Jeong FAN Maohong Johannes van leeuwen Joshua F. Belczyk Department of Civil Construction and Environmental Engineering Iowa State University Ames IA 50011 USA. Center for Sustainable Environmental Technology Iowa State University Ames IA 50011 USA Bailey PVS Canonsburg PA 15317 USA

The study focused on the effect of several typical competing solutes on removal of arsenic with Fe2O3 and Al2O3. The test results indicate that chloride, nitrate and sulfate did not have detectable effects, and that selenium（Ⅳ）（Se（Ⅳ）） and vanadium（Ⅴ）（V（Ⅴ）） showed slight effects on the adsorption of As（Ⅴ） with Fe2O3. The results also showed that adsorption of As（Ⅴ） on A12O3 was not affected by chloride and nitrate anions, but slightly by Se（Ⅳ） and V（Ⅴ） ions. Unlike the adsorption of As（Ⅴ） with Fe2O3, that with Fe2O3 was affected by the presence of sulfate in water solutions. Both phosphate and silica have significant adverse effects on the adsorption of As（Ⅴ） adsorption with Fe2O3 and Al2O3. Compared to the other tested anions, phosphate anion was found to be the most prominent solute affecting the As（Ⅴ） adsorption with Fe2O3 and Al2O3. In general, Fe2O3 has a better performance than Al2O3 in removal of As（Ⅴ） within a water environment where multi competing solutes are present.

关键词： adsorption arsenic iron oxide aluminum oxide sulfate selenium(Ⅳ) vanadium(Ⅴ) phosphate silica

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GrapevineXL reliably predicts multi-annual dynamics of vine water status, berry growth, and sugar accumulation in vineyards

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Horticulture Research 2023年第6期10卷 56-69页

作者： Weiwei Yang Junqi Zhu Cornelis van leeuwen Zhanwu Dai Gregory AGambetta Beijing Key Laboratory of Grape Science and Enology and Key Laboratory of Plant Resources Institute of Botanythe Chinese Academy of SciencesBeijing100093China EGFV Univ.BordeauxBordeaux Sciences AgroINRAEISVVVillenave d’Ornon33882France The Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization in Xinjiang Production and Construction Group College of AgricultureShihezi UniversityShihezi832000China The New Zealand Institute for Plant&Food Research Limited Blenheim 7201New Zealand China National Botanical Garden Beijing 100093China

Climate and water availability greatly affect each season’s grape yield and *** models to accurately predict environment impacts on fruit productivity and quality is a huge *** calibrated and validated the functional-structural model,GrapevineXL,with a data set including grapevine seasonal midday stem water potential(�xylem),berry dry weight(DW),fresh weight(FW),and sugar concentration per volume([Sugar])for a wine grape cultivar(Vitis vinifera *** Franc)in field conditions over 13 years in Bordeaux,*** results showed that the model could make a fair prediction of seasonal�xylem and good-to-excellent predictions of berry DW,FW,[Sugar]and leaf gas exchange responses to predawn and midday leaf water potentials under diverse environmental conditions with 14 key *** running virtual experiments to mimic climate change,an advanced veraison(*** onset of ripening)of 14 and 28 days led to significant decreases of berry FW by 2.70%and 3.22%,clear increases of berry[Sugar]by 2.90%and 4.29%,and shortened ripening duration in 8 out of 13 simulated years,***,the impact of the advanced veraison varied with seasonal patterns of climate and soil water ***,the results showed that the GrapevineXL model can predict plant water use and berry growth in field conditions and could serve as a valuable tool for designing sustainable vineyard management strategies to cope with climate change.

关键词： Sugar cultivar sugar

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