Currently 884 million people worldwide are living without access to an improved source of drinking water (WHO/UNICEF, 2011). Piped-water on premises is the ultimate goal of World Health Organization (WHO) due to the ability to treat all of the water and distribute it safely in pressurized pipes. However, Household Water Treatment and Safe Storage (HWTS) is an option for improving the quality of drinking water where that infrastructure is not yet developed, especially where there is a risk of recontamination between point of collection and point of use (Clasen, 2006). This study analyzed one such HWTS, the ceramic pot water filter. The study compared the hydraulic properties of the FilterPure (FP) and Potters for Peace (PFP) ceramic pot filters through a thirteen-month field study in the Dominican Republic and laboratory studies at the University of South Florida. In the field study 55 filters were tested for first hour flow rate and hydraulic conductivity. Eight first hour flow rate tests were conducted in the field on one month intervals during months 7- 13. FP filters had an average first hour flow rate of 553 ml/hr and PFP Filters had a first hour flow rate of 395 ml/hr. No significant change in first hour flow rate was observed over time in FP filters. PFP experienced an average increase of 31 ml/hr per month during the seven-month testing period. Falling head tests were conducted on four filters in the laboratory and the flow rate was modeled to determine hydraulic conductivity. Hydraulic conductivity values for FP filters ranged from k = 0.0495 - 0.0831 cm/hr and for PFP filters ranged from k = 0.0136 - 0.0389 cm/hr. Eight out of 29 (26%) Potters for Peace filters in the field had first hour flow rates of less than 250 ml/hr by month nine of the study and had to be replaced and removed from the study. In total 24 of 55 (44%) filters (8 FP and 16 PFP) had to be removed from the study due to several reasons discussed in this thesis.

The objective of this research was to develop fluorescence-based tools that are suitable for performing rapid, accurate and direct characterization of natural organic matter (NOM) and colloidal/particulate substances present in natural water. Most available characterization methods are neither suitable for characterizing all the major NOM fractions such as protein-, humic acid-, fulvic acid- and polysaccharide-like substances as well as colloidal/particulate matter present in natural water nor are they suitable for rapid analyses. The individual and combined contributions of these NOM fractions and colloidal/particulate matter present in natural water contribute to membrane fouling, disinfection by-products formation and undesirable biological growth in drinking water treatment processes and distribution systems. The novel techniques developed in this research therefore, provide an avenue for improved understanding of these negative effects and proactive implementation of control and/or optimization strategies. The fluorescence excitation-emission matrix (EEM) method was used for characterization of NOM and colloidal/particulate matter present in water. Unlike most NOM and colloidal/particulate matter characterization techniques, this method can provide fast and consistent analyses with high instrumental sensitivity. The feasibility of using this method for monitoring NOM at very low concentration levels was also demonstrated with an emphasis on optimizing the instrument parameters necessary to obtain reproducible fluorescence signals. Partial least squares regression (PLS) was used to develop calibration models by correlating the fluorescence EEM intensities of water samples that contained surrogate NOM fractions with their corresponding dissolved organic carbon (DOC) concentrations. These fluorescence-based calibration models were found to be suitable for identifying/monitoring the extent of the relative changes that occur in different NOM fractions and the interactions between polysaccharide- and protein-like NOM in water treatment processes and distribution systems. Principal component analysis (PCA) of fluorescence EEMs was identified as a viable tool for monitoring the performance of biological filtration as a pre-treatment step, as well as ultrafiltration (UF) and nanofiltration (NF) membrane systems. The principal components (PCs) extracted in this approach were related to the major membrane foulant groups such as humic substances (HS), protein-like and colloidal/particulate matter in natural water. The PC score plots generated using the fluorescence EEMs obtained after just one hour of UF or NF operation could be related to high fouling events likely caused by elevated levels of colloidal/particulate-like material in the biofilter effluents. This fluorescence EEM-based PCA approach was sensitive enough to be used at low organic carbon levels present in NF permeate and has potential as an early detection method to identify high fouling events, allowing appropriate operational countermeasures to be taken. This fluorescence EEM-based PCA approach was also used to extract information relevant to reversible and irreversible membrane fouling behaviour in a bench-scale flat sheet cross flow UF process consisting of cycles of permeation and back-washing. PC score-based analysis revealed that colloidal/particulate matter mostly contributed to reversible fouling, while HS and protein-like matter were largely responsible for irreversible fouling. This method therefore has potential for monitoring modes of membrane fouling in drinking water treatment applications. The above approach was further improved by utilizing the evolution of the PC scores over the filtration time and relating these to membrane fouling by the use of PC scores??? balanced-based differential equations. Using these equations the proposed fluorescence-based modeling approach was capable of forecasting UF fouling behaviours with good accuracy based solely on fluorescence data obtained at time = 15 min from the initiation of the filtration process. In addition, this approach was tested experimentally as a basis for optimization by modifying the UF back-washing times with the objective of minimizing energy consumption and maximizing water production. Preliminary optimization results demonstrated the potential of this approach to reduce power consumption by significant percentages. This approach was also useful for identifying the fouling components of the NOM that were contributing to reversible and irreversible membrane fouling. Grand River water (Southwestern Ontario, Canada) was used as the natural water source for developing the techniques presented in this thesis. Future research focusing on testing these methods for monitoring of membrane fouling and treatment processes in large-scale drinking water treatment facilities that experience different sources of raw water would be useful for identifying the limitation of these techniques and areas for improvements.

Wastewater treatment is traditionally considered a separate part of an industrial activity, hardly connected to the production units themselves. It is nowadays essential to ensure that the quality of water is not degraded and that water that has been polluted is purified to acceptable levels, especially in a country with scarce water resources such as South Africa. Where water quality is concerned, Zero Effluent Discharge (ZED) is the ultimate goal, in order to avoid any releases of contaminants to the water environment. The push towards ZED in South Africa is also promoted further by the South African Government’s plan to reduce freshwater usage and the pollution of water sources due to the water scarcity in a semi-arid South Africa. Future legislation will see a marked increase in the cost of freshwater usage and/or a possible limitation of the quantity of freshwater available. There is a need in the South African Industry for a framework of Best Management Practices (BMPs) in order to provide interested stakeholders, which include not only industry, but also academia, environmental interest groups and members of the public, with a procedure to meet the ZED statutory requirements. This dissertation explores the regulatory requirements and current environmental management practices implemented. A framework of BMPs to successfully attain ZED status in South African industries is developed from the literature study and the researcher’s own experience. The BMP framework embodies practices for one integrated strategy within three dimensions. The three dimensions of the BMP framework were selected to differentiate between BMPs for management (Governance BMPs), the project management team responsible for ZED projects (Project Management BMPs) and the implementation of preventative and operational measures to obtain and sustain ZED compliance for South African industries. The BMP framework was validated against the practices applied by Mittal Steel. The Mittal Steel plant in Vanderbijlpark implemented various projects, reduced the intake of water and eliminated the discharge of effluent and by doing this successfully realised their ZED status. The BMP framework will enable South African industries to develop their own BMPs Manual which should be specific to their operational and environmental requirements. The implementation of these BMPs should be tailored and used accordingly to demonstrate compliance to ZED requirements in South African industries. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2009.

Wastewater treatment is traditionally considered a separate part of an industrial activity, hardly connected to the production units themselves. It is nowadays essential to ensure that the quality of water is not degraded and that water that has been polluted is purified to acceptable levels, especially in a country with scarce water resources such as South Africa. Where water quality is concerned, Zero Effluent Discharge (ZED) is the ultimate goal, in order to avoid any releases of contaminants to the water environment. The push towards ZED in South Africa is also promoted further by the South African Government’s plan to reduce freshwater usage and the pollution of water sources due to the water scarcity in a semi-arid South Africa. Future legislation will see a marked increase in the cost of freshwater usage and/or a possible limitation of the quantity of freshwater available. There is a need in the South African Industry for a framework of Best Management Practices (BMPs) in order to provide interested stakeholders, which include not only industry, but also academia, environmental interest groups and members of the public, with a procedure to meet the ZED statutory requirements. This dissertation explores the regulatory requirements and current environmental management practices implemented. A framework of BMPs to successfully attain ZED status in South African industries is developed from the literature study and the researcher’s own experience. The BMP framework embodies practices for one integrated strategy within three dimensions. The three dimensions of the BMP framework were selected to differentiate between BMPs for management (Governance BMPs), the project management team responsible for ZED projects (Project Management BMPs) and the implementation of preventative and operational measures to obtain and sustain ZED compliance for South African industries. The BMP framework was validated against the practices applied by Mittal Steel. The Mittal Steel plant in Vanderbijlpark implemented various projects, reduced the intake of water and eliminated the discharge of effluent and by doing this successfully realised their ZED status. The BMP framework will enable South African industries to develop their own BMPs Manual which should be specific to their operational and environmental requirements. The implementation of these BMPs should be tailored and used accordingly to demonstrate compliance to ZED requirements in South African industries. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2009.

The elimination of natural organic matter (NOM) is an important aim of water treatment in demineralisation plants of power stations. NOM is regarded as corrosion risk factor in the steam water cycle because of its potential to decompose into low-molecular-weight (LMW) acids and carbon dioxide. Further, the removal of NOM is also one of the main objectives in the drinking water production, since it can cause i) colour, taste and odour problems, ii) formation of carcinogen halogenated disinfection by-products (DBPs) after disinfection with chlorine and iii) bacterial growth in the water distribution system. In earlier studies, it was found that anion exchange is a successful method to remove NOM fractions. However, NOM fractions with low charge density (LMW neutrals and hydrophobic organic carbon (HOC)) and/or large molecular size (biopolymers and particulate organic carbon (POC)) could not be removed in some cases in satisfying quantities. The aim of the present work was to investigate the uptake performance of different anion exchange resins (AERs) in regard to problematic NOM fractions. The AERs differ especially in their functional groups (tertiary versus quaternary amines) and matrix material (polystyrene versus polyacrylic resins). The use of different AERs provides an option to identify possible interactions between adsorbate (NOM fractions) and adsorber (AERs) as well as the mechanism which determine the removal efficiency. The NOM fraction adsorption onto AERs was studied in equilibrium and fixed-bed experiments with three types of starch with different molecular size distributions (model substances for biopolymer fraction) as well as 2-naphthol (model substance for the LMW neutral fraction) at acidic pH (relevant for water in demineralisation plants of power stations) and neutral pH (covering most raw waters). Furthermore, the NOM fraction uptake from “real” acidic and neutral water samples, obtained from a demineralisation plant of a power station, was estimated for different AERs. Results were discussed in terms of size-exclusion, anion exchange and hydrophilic/hydrophobic repulsion. In case that size-exclusion influences the NOM uptake onto AERs, it was found that the smaller the size of the NOM molecules and the higher the water content of the AERs, the more effective the uptake is. Thus, for the removal of biopolymers and POC, polyacrylic resins with high water content could be a good choice. Contrary, polystyrene AERs are the most effective resins in the removal of NOM fractions, if no size-exclusion occurs. They seem to be able to uptake more hydrophilic NOM fractions by polar/ionic interactions between acids/acidic components and tertiary/quaternary amines as well as to remove more hydrophobic NOM fractions by π-π stacking and/or hydrophobic interactions on the polystyrene matrix. Further, it was found that the higher the total volume (anion exchange) capacity of an AER, the higher its NOM removal by polar/ionic interactions can be. At acidic pH, weak/medium base AERs have higher total volume (anion exchange) capacities than strong base AERs, whereas, at neutral pH, strong base AERs have the highest ones. In view of these results, the application of polyacrylic AERs with high water content can be recommended to remove NOM components with large molecular size in demineralisation and drinking water plants. If there is a higher amount of smaller NOM fractions, especially LMW neutrals, than polystyrene weak/medium base AERs should be favoured in demineralisation plants and polystyrene strong base AERs in drinking water treatment plants. From the engineering point of view, breakthrough curve (BTC) prediction models are important for the design of fixed-bed filter. Therefore, two different BTC model approaches were tested in the present study to describe the single-solute adsorption onto AERs: i) the homogenous surface diffusion model (HSDM) with linear driving force (LDF) approach for surface diffusion, known from activated carbon adsorption, and ii) the Glueckauf/Helfferich formulae as an extension of the height equivalent to a theoretical plate (HETP) model, initially used to describe ion exchange processes. It was found that the Glueckauf/Helfferich approach is not only a suitable tool for the fast calculation of BTCs for ionic components, but it can also successfully be applied, after considering the Freundlich model for the mass balance, for the rapid prediction of BTCs for single-solute organic molecules. For competitive BTC predictions, the ideal adsorbed solution theory (IAST) within the LDF model was applied. All calculated BTCs fit the experimental data in a good manner. Thus, the investigated BTC models can be applied for estimating the breakthrough bed volumes of different AERs to avoid leakage of NOM in the drinking or demineralised water caused by overloading. / Die Entfernung von natürlichen organischen Substanzen (NOM) ist ein wichtiges Ziel für die Herstellung von Reinstwasser im Kraftwerksbetrieb, da diese sich im Wasser/Dampf-Kreislauf zu niedermolekularen Säuren und Kohlenstoffdioxid zersetzen können und so ein potentielles Korrosionsrisiko darstellen. Außerdem ist die Elimination von natürlichen organischen Substanzen einer der Schwerpunkte in der Trinkwasseraufbereitung, da NOM im Trinkwasser folgende Konsequenzen verursachen können i) Farb-, Geschmacks- und Geruchsprobleme, ii) Bildung von kanzerogen halogenierten Desinfektionsnebenprodukten nach der Desinfektion mit Chlor und iii) Bakterienwachstum im Wasserverteilungssystem. In früheren Untersuchungen wurde festgestellt, dass Anionenaustauscherharze (AERs) die NOM-Fraktionen in der Regel erfolgreich aufnehmen können. Nur NOM-Fraktionen mit geringer Ladungsdichte (niedermolekulare Neutralstoffe und hydrophober organischer Kohlenstoff) und/oder großer Molekülgröße (Biopolymere und partikulärer organischer Kohlenstoff) können unter bestimmten Bedingungen nicht in zufriedenstellender Menge entfernt werden. Ziel dieser Arbeit war es, das Aufnahmeverhalten unterschiedlicher AERs hinsichtlich problematischer NOM-Fraktionen zu untersuchen. Die AERs unterscheiden sich vor allem in ihren funktionellen Gruppen (tertiäre versus quaternäre Amine) und ihrer Matrix (Polystyren- versus Polyacryl-Harze). Die Verwendung unterschiedlicher AERs erlaubt es, mögliche Wechselwirkungen zwischen Adsorbat (NOM-Fraktionen) und Adsorber (AERs) und die Mechanismen, die die NOM-Aufnahme entscheidend bestimmen, zu identifizieren. Die Entfernung von NOM-Fraktionen durch AERs wurde in Gleichgewichts- und Festbett-versuchen mittels dreier Stärketypen mit unterschiedlicher Molekülgrößenverteilung (Modellsubstanzen für die Biopolymere) und 2-Naphthol (Modellsubstanz für die Neutralstoffe) unter sauren pH-Bedingungen (relevant für die Herstellung von Reinstwasser im Kraftwerksbetrieb) und neutralen pH-Bedingungen (bedeutsam für die meisten Rohwässer) untersucht. Außerdem sollte das Adsorptionsverhalten von AERs bezüglich verschiedener NOM-Fraktionen unter Einsatz von „real“ neutralen und sauren Wasserproben aus einer Wasseraufbereitungsanlage eines Kraftwerksbetriebes eingeschätzt werden. In dieser Arbeit konnte gezeigt werden, dass falls Größenausschluss die NOM-Aufnahme von AERs beeinflusst, dann ist die Adsorption der NOM-Fraktionen umso größer, je kleiner die NOM-Moleküle sind und je höher der Wassergehalt der AERs ist. Daher kann für die Entfernung von größeren Biopolymeren, der Einsatz von AERs mit Polyacryl-Matrix und hohem Wassergehalt die beste Option sein. AERs mit Polystyren-Matrix besitzen die höchste Aufnahmekapazität für NOM-Fraktionen, falls kein Größenausschluss auftritt. Es scheint für sie möglich zu sein, sowohl hydrophile NOM-Fraktionen durch polare/ionische Wechselwirkungen zwischen NOM Säuren/sauren Komponenten und tertiären/quaternären Aminen aufzunehmen als auch hydrophobe NOM-Fraktionen durch π-π Anziehungen und/oder hydrophobe Interaktionen an die Polystyren-Matrix zu binden. Weiterhin konnte gezeigt werden, dass je höher die Gesamtvolumenkapazität eines AERs, desto größer ist die NOM-Entfernung auf Grund von polaren/ionischen Wechselwirkungen. Es gilt, dass schwach/mittel basische AERs im Vergleich zu stark basischen AERs höhere Gesamtvolumenkapazitäten unter sauren pH-Bedingungen besitzen und stark basische AERs die höchsten Gesamtvolumenkapazitäten unter neutralen pH-Bedingungen aufweisen. Auf Grund dieser Ergebnisse ist es möglich, die Verwendung von AERs mit Polyacryl-Matrix und hohem Wassergehalt für die Entfernung von NOM-Fraktionen mit großer Molekülgröße in Reinst- und Trinkwasseraufbereitungsanlagen zu empfehlen. Falls es einen höheren Anteil von kleineren NOM-Fraktionen, im Besonderen Neutralstoffen, gibt, sollte die Verwendung von schwach/mittel basischen AERs in Vollentsalzungsanlagen von Kraft-werksbetrieben und stark basischen AERs in Trinkwasseraufbereitungsanlagen bevorzugt werden. Vor allem im Hinblick auf technische Anwendungen ist es wichtig, Durchbruchskurven (BTC) vorausberechnen zu können. In der vorliegenden Arbeit wurden zwei Modellansätze für die Berechnung von BTCs für die Einkomponentenadsorption getestet: i) das homogene Oberflächendiffusionsmodell mit linearer Triebkraft (LDF), bekannt aus Untersuchungen zur Aufnahme von NOM an Aktivkohle, und ii) die Glueckauf/Helfferich-Formeln, primär verwendet für die Beschreibung von Ionenaustauschprozessen. Es konnte gezeigt werden, dass das Glueckauf/Helfferich-Verfahren nicht nur ein geeignetes Instrument für die schnelle Berechnung von BTCs für ionische Komponenten ist, sondern dass dieses, nach Berücksichtigung des Freundlich-Ansatzes in der Massenbilanz, auch erfolgreich angewendet werden kann, um BTCs für Einkomponentenadsorption von Organika zu berechnen. Für die Vorausberechnung von BTCs für Mehrkomponentensysteme wurde die Theorie der idealen adsorbierten Lösung im LDF-Modell genutzt. Die berechneten BTCs stimmen in guter Qualität mit den experimentell ermittelten BTCs überein. Die Ergebnisse verdeutlichen, dass die untersuchten BTC-Modelle eingesetzt werden können, um Durchbruchspunkte für die jeweiligen AERs zu bestimmen und damit die Gefahr des Schlupfes von NOM ins Trink- bzw. Reinstwasser zu minimieren.

Wastewaters from textile industry contain organic dyes, which cannot be easily treated by biological methods. Therefore, pretreatment by an advanced oxidation process (AOP) is needed in order to produce more readily biodegradable compounds and to remove color and chemical oxygen demand (COD) simultaneously. In this research, ozone (O3) is combined with hydrogen peroxide (H2O2) for the advanced oxidation of an azo dye solution, namely aqueous solution of Acid Red 151, which is called as &ldquo / Peroxone process&rdquo / . The aim of the study is to enhance the ozonation efficiency in treating the waste dye solution. The effects of pH, initial dye and initial ozone concentrations and the concentration ratio of initial H2O2 to initial O3 on color and COD removals were investigated. Also, the kinetics of O3-dye reaction in the presence of H2O2 was approximately determined. As a result of the experimental study, it was seen that an increase in the initial dye concentration at a constant pH and initial ozone concentration did not change the COD % removal significantly, from a statistical analysis of the data. The results obtained at pH values of 2.5 and 7 gave higher oxidation efficiencies in terms of color and COD removals compared to those at pH of 10. The best initial molar ratio of H2O2 to O3 was found to be 0.5, which yielded highest treatment efficiency for each pH value studied. The results of the excess dye experiments suggest that the ozonation of Acid Red 151 follows an average first order reaction with respect to ozone at pH=2.5 and pH=7 whereas it is around 0.56 at pH=10. By Initial Rate Method, the orders with respect to individual reactants of O3 and dye were determined as one, the total order of the reaction being two for all the studied pH. As a conclusion, a further study of the peroxone process at a pH of 10 can be recommended to determine the reaction kinetics and mechanism at this pH, where radicals play an important role.

Saxitoxins were extracted from a bloom of toxic Anabaena circinalis and used to spike treated water from Hope Valley Reservoir (HVTW) and Milli-Q water. The waters were treated with ozone using the batch method and saxitoxin levels were measured in the samples using HPLC. The results for oxidation of saxitoxins in Milli-Q water versus HVTW show that despite the presence of natural organic matter(NOM) and the production of vastly different ozone residuals, there was a similar removal of all saxitoxins in both waters. The results show that high concentrations of saxitoxins were present in solution after ozonation with doses and contact times typically used in water treatment. Relating the toxin destruction to ozone residual showed that even with a residual ozone concentration of 0.8 mg/L after 10 minutes contact in HVTW, over 60% of the initial saxitoxin content was still present in the samples. The presence of an ozone residual in the water could not be related to saxitoxin destruction and it appeared that saxitoxin removal occurred more rapidly when ozone was consumed rather than stabilised in solution. The results indicate that the mechanism for toxin removal is probably based on the reaction with a hydroxyl radical species as the oxidant rather than molecular ozone. The results obtained during these experiments indicate that ozone is not an effective oxidant for this class of compound. A range of ozone doses were applied to two different treated reservoir waters that had been spiked with microcystins LA (mLA) and LR (mLR). At the ozone dose where a residual was first measured in the sample after 5 minutes exposure time, no microcystins were detected by HPLC in either water. The removal of mLA and mLR was identical in all samples. The absence of mLA and mLR by HPLC was supported by a loss of toxicity using a highly sensitive and specific bioassay (PP2A) and by in vivo studies in mice. In both waters microcystins were removed with an ozone dose typical of that used in drinking water treatment. The results indicate that conventional ozone treatment was effective in removing hepatotoxicity at microcystin levels greater than those likely to be found in drinking water. Two waters were sampled from reservoirs in South Australia. One was collected directly from Happy Valley Reservoir (HVRW) and the other from Myponga Reservoir after treatment but before chlorination (MFCW). They were spiked with mLA and mLR and chlorinated to measure toxin removal and chlorine consumption using the CT concept. In MFCW at pH 7 there was a better removal of both mLA and mLR than in HVRW at pH 8.1. There was also a lesser effect from water temperature upon toxin removal in MFCW. Microcystin LA was less easily removed than mLR at both temperatures in both waters. For HVRW, at the higher pH, this required an initial dose of 7 mg/L of chlorine which corresponded to a CT of around 70 min.mg/L. If the water temperature was reduced to 6??C then under these conditions there would still be 40% of the initial concentration of mLA and mLR present in this water. At this temperature a final chlorine residual of 3.5 mg/L after 30 minutes, requiring a chlorine dose of 8mg/L and corresponding to a CT of about 95 min.mg/L, was required to reduce microcystin levels below the WHO guidelines. This implies that in colder climates the application of chlorine for microcystin removal may require elevated chlorine doses and CT values. Arrhenius activation energies were calculated for mLA and mLR in both waters, revealing different Ea values for both toxins. Due to the complexity of the reactions and the possible effects of pH in solution, this system was considered too complicated to be described by the Arrhenius equation. NOM was collected from Myponga Reservoir in South Australia using magnetic ion exchange (MIEX??) resin. The collected NOM was desorbed and separated into fractions of different molecular weight and character using ultrafiltration and mixed resin ion exchange. At approximately 5 mg/L dissolved organic carbon (DOC) the measured apparent second order rate constant (kapp) for mLA and mLR removal was fairly similar in both the high molecular weight fraction (designated F3), and the intermediate high molecular weight fraction (designated F2). The low molecular weight fraction (designated EN) had slightly higher kapp values as would be expected due to the less reactive nature of the NOM in this fraction. This meant more chlorine was available to react with microcystins in this fraction. Fractions F3 and F2 produced similar kapp values to those from the parent water source following treatment, indicating the similar reactivity of these NOM fractions at comparable DOC levels. Increasing the DOC concentration in the F2 fraction increased kapp for both mLA and mLR due to the additional chlorine needed to react with the additional NOM present. The results showed that pH, temperature and DOC concentration have a higher impact upon chlorination rates, and the efficiency of toxin removal, than NOM character alone. In general it is assumed that chlorine will be more effective at removing toxins in water with a low SUVA and low specific colour as these indicate less 'reactive' NOM in the water. The results of this study show that toxin removal was more effective in the EN fraction as indicated by the higher kapp. This fraction also had the lowest SUVA and lowest specific colour which supports the generally held view in water treatment. Relating the toxin removal to chlorine residual in these reconstituted fractionated NOM samples, indicated that a residual of around 1.5 mg/L after 30 minutes contact was generally adequate to remove all toxins in water with a DOC level of around 5 mg/L. This is consistent with the results obtained in real waters, where at 20??C a chlorine residual of 2 mg/L was found to be sufficient for removal of both mLA and mLR.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-03-23T20:01:22Z No. of bitstreams: 1 JULYANNA DAMASCENO PESSOA - DISSERTAÇÃO PPGEQ 2015..pdf: 3056060 bytes, checksum: f1c90789fd3af9574cb10fbc1d69a075 (MD5) / Made available in DSpace on 2018-03-23T20:01:22Z (GMT). No. of bitstreams: 1 JULYANNA DAMASCENO PESSOA - DISSERTAÇÃO PPGEQ 2015..pdf: 3056060 bytes, checksum: f1c90789fd3af9574cb10fbc1d69a075 (MD5) Previous issue date: 2014-12-15 / Em decorrência da degradação dos recursos hídricos e da crescente preocupação com microrganismos específicos na água, a utilização de membranas cerâmicas para separação de materiais contaminantes, passa a ser uma opção de tratamento para a produção de água potável, devido a motivos como, por exemplo, sua resistência ao ataque de produtos químicos, requerer uma menor área de construção do equipamento, maior economia de energia, dentre outros. O presente trabalho objetivou estudar o desempenho de um sistema híbrido, composto por membrana cerâmica tubular de microfiltração, recheadas por resinas trocadoras iônicas, para tratamento de água de qualidade inferior. As membranas utilizadas nesse trabalho são do tipo α-alumina (α-Al2O3), tamanho nominal de poro de aproximadamente 0,8 µm, produzidas pelo Laboratório de Membranas Cerâmicas (LABCEM) do Laboratório de Referência em Dessalinização (LABDES) na Universidade Federal de Campina Grande (UFCG). O sistema foi avaliado em função do fluxo e vazão do permeado, nas pressões de operação 0,5; 1,0; 2,0 e 3,0 bar; teste de presença / ausência e contagem bacteriológicas na água da alimentação e permeado para o sistema: membrana cerâmica; análises físicoquímicas realizadas para o sistema: membrana cerâmica/ RTI; e tempo de residência hidráulica ( ), nas pressões de operação 1,0; 2,0 e 3,0 bar. A membrana cerâmica removeu completamente os Coliformes totais e fecais (Escherichia coli) da água. O comportamento do fluxo do permeado variou com a pressão de operação. No sistema híbrido: membrana cerâmica/ RTI, o tempo de residência foi de 15,55 segundos na pressão de operação 1,0 bar, removendo 71,9% dos íons da água de alimentação, para 66% na pressão 2,0 bar ( =11,73 segundos) e 61% na de 3,0 bar ( = 10,11 segundos). O sistema híbrido mostrou-se eficiente na remoção dos parâmetros físico-químicos e produziu água tratada de boa qualidade quanto aos parâmetros bacteriológicos nas águas de qualidade inferior, com baixo consumo energético. / Due to the degradation of water resources and the increasing concern about specific microorganisms in water, the use of ceramic membranes for separation of contaminating materials, becomes a treatment option for the production of drinking water, due to reasons such as its resistance to chemicals, requires a smaller area of equipment construction, greater energy savings, among others. This study investigated the performance of a hybrid system consisting of a tubular microfiltration ceramic membrane, filled with ion exchange resins for substandard water treatment. The membranes used in this work are the α-alumina type (α-Al2O3), with pores which have a nominal diameter of about 0.8 microns produced by Laboratório de Membranas Cerâmicas (LABCEM), at Desalination in Reference Laboratory (LABDES) at the Federal University of Campina Grande (UFCG). The system was evaluated by the flow and permeate flow, the operating pressure 0.5; 1.0; 2.0 and 3.0 bar; presence / absence and bacteriological count tests in the feed and permeate water for the system: ceramic membrane; Physical and chemical analysis for the system: ceramic membrane / RTI; and hydraulic residence time (τ), at the operating pressures of 1.0; 2.0 and 3.0 bar. The ceramic membrane completely removed the Total and fecal (Escherichia coli) Coliform of the water. The permeate flux behavior varied with the operating pressure. In the hybrid system: ceramic membrane / RTI residence time was 15.55 seconds at the operating pressure of 1.0 bar by removing 71.9% of the feed water ions, to 66% at 2.0 bar pressure ( = 11.73 seconds), and 61% for the 3.0 bar ( = 10.11 seconds). The hybrid system was efficient in the removal of physical and chemical parameters and produced good quality treated water as for the bacteriological parameters in lower quality water with low power consumption.

Orientador: Sérgio Luís de Carvalho / Banca: Edson Pereira Tangerino / Banca: Domingos Sávio Barbosa / Resumo: O aumento da contaminação de corpos hídricos por pesticidas juntamente com o melhor conhecimento das propriedades nocivas desses poluentes, têm aumentado o interesse na remoção destes compostos durante o tratamento de água potável. Sendo os pesticidas constituídos por moléculas biologicamente ativas e de difícil remoção durante o processo convencional de tratamento de água, o uso de filtros lentos de areia seguidos por filtros de carvão ativado biologicamente pode representar um sistema eficiente no tratamento de água. Considerando estes aspectos, o presente estudo teve como objetivo avaliar a eficiência da filtração lenta e da filtração utilizando carvão ativado biológico (CAB) na remoção do herbicida atrazina em escala de bancada e a composição fenotípica e genotípica dos microrganismos associados na degradação do herbicida. A remoção de atrazina atingiu uma remoção próxima de 100% nos efluentes dos filtros de areia e carvão. Foi verificada a presença de microrganismos (Bacillus e Salirhabdus) em ambos conjunto de filtros, podendo estes estarem ligados à degradação do herbicida da água. Os resultados deste estudo demonstraram eficiência na remoção de atrazina em níveis resguardados pela legislação sanitária, possibilitando o uso deste sistema na remoção do herbicida avaliado, assegurando a distribuição e consumo humano desta água. Além de avaliar a viabilidade do uso de filtros biológicos de carvão antecedidos por filtros lentos de areia na remoção de pesticidas, o presente trabalho poderá contribuir para realização de novas pesquisas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increased contamination of watercourses by pesticides along with better knowledge of the harmful properties of these pollutants have increased interest in the removal of these compounds during treatment of drinking water. Since pesticides consisting of biologically active molecules and hard to remove during conventional water treatment, use of slow sand filters followed by biologically activated carbon filters may represent an efficient system for water treatment. Considering these aspects, this study aimed to evaluate the efficiency of slow sand filtration and biological filtration using activated carbon (BAC) in the removal of the herbicide atrazine in bench scale and phenotypic and genotypic composition of the microorganisms involved in degradation of the herbicide. The removal of atrazine reached a level close to 100% in effluent from sand and carbon filters compounds. We observed the presence of microorganisms (Bacillus and Salirhabdus) in both set of filters and they can be linked to degradation of the herbicide from water. The results showed removal efficiency of atrazine at levels controlled by the health legislation, enabling the use of this system in the removal of the herbicide evaluated, ensuring the distribution and consumption of water. Besides evaluating the feasibility of using biological filters charcoal preceded by slow sand filters for removal of pesticides, this study may contribute to new research on the technologies used in the treatment of drinking water contaminated by recalcitrant compounds. / Mestre

Ce projet vise à contribuer à la gestion durable d'une ressource naturelle essentielle, l'eau, à travers le développement d'une technologie innovante basée sur le couplage d’un procédé de filtration baromembranaire et de procédés d'oxydation avancée électrochimiques (POAE) afin de minéraliser des molécules organiques très stables.Comme ces polluants dits bio-réfractaires ne peuvent pas être dégradés par les procédés d’oxydation classiques (biologiques, O3, Cl2, H2O2…), les procédés d'oxydation avancée (POA) sont alors envisagés. En électrochimie, les radicaux hydroxyles peuvent être générés sur des cathodes en carbone par le procédé électro-Fenton ou encore à l’anode sur des matériaux à forte surtension de dégagement d'oxygène tels que l'oxyde de titane sous-stœchiométrique ou le diamant dopé au bore (DDB) par une réaction d'oxydation de l'eau.Ce travail porte sur l'élaboration et la caractérisation de membranes tubulaires de filtration composées des phases Magnéli les plus conductrices électroniques : Ti4O7 et Ti5O9. Ce matériau peut être utilisé dans le procédé d’oxydation anodique avec un coût de fabrication plus faible que le diamant dopé au bore. Des membranes tubulaires de microfiltration composées de ces phases ont été préparées en collaboration avec le Centre de Recherches et d’Études Européen du groupe Saint-Gobain. Celles-ci ont été élaborées par réduction carbothermique de TiO2, ce qui est très novateur par rapport à la réduction sous dihydrogène. Des poudres de TinO2n-1 (avec 3 ≤ n ≤ 5) ont été préparées par électrofusion de poudres de TiO2 et de carbone suivie de broyages. Ces poudres de granulométrie contrôlée ont ensuite été utilisées à l’IEM pour préparer des suspensions stables de particules en vue de réaliser des couches minces de basse microfiltration, par trempage ou engobage, composées de TinO2n-1 (avec 4 ≤ n ≤ 6). Nous proposons également une première méthode d’élaboration de couches minces en TinO2n-1 (n à définir) par voie sol-gel suivie d’un traitement thermique dans le but d’obtenir des couches réactives d’ultra et de nanofiltration. Après optimisation, ces matériaux ont pu montrer leur efficacité vis-à-vis de la dégradation de polluants bio-réfractaires de type pharmaceutique (Paracétamol) lorsqu’ils sont utilisés en tant que « membranes réactives électrochimiques » que ce soit en mode statique (bécher) ou en mode dynamique (pilote de filtration). La prochaine étape portera sur le couplage des procédés d’oxydation anodique et de filtration baromembranaire utilisant les membranes réactives développées. Au vu des premiers tests, cette technologie s’avère d’ores et déjà prometteuse pour le traitement de polluants bio-réfractaires dans l’eau. Cette thèse a été financée par l'Agence Nationale de la Recherche (ANR) dans le cadre du programme ECO-TS (Projet CElectrON). / This project aims to contribute to the sustainable management of water as an essential natural resource, through the development of an innovative technology based on the coupling of a baromembranar filtration process and electrochemical advanced oxidation processes (EAOP) in order to mineralize very stable organic molecules.Since these bio-refractory pollutants cannot be totally degraded by common oxidants (biological, O3, Cl2, H2O2), advanced oxidation processes (AOP) are thus considered. In electrochemistry, these hydroxyl radicals can be generated by water oxidation on carbon cathodes by the electro-Fenton process or on anode showing high oxygen evolution overvoltage like sub-stoichiometric titanium oxide and Boron Doped Diamond (BDD).This work deals with the development and characterization of tubular filtration membranes composed of the most conductive Magnéli phases: Ti4O7 and Ti5O9. These materials can be used in anodic oxidation process with lower manufacturing cost compared to BDD. Microfiltration tubular membranes composed of these phases were prepared with the support of CREE (Research Group of Saint-Gobain). They were elaborated by carbothermal reduction of TiO2, which is very innovative compared to dihydrogen reduction. TinO2n-1 powders (with 3 ≤ n ≤ 5) of controlled grain size were elaborated by electrofusion of TiO2 powder and coke followed by grinding. These powders were further used at the European Institute of Membranes to formulate stable suspensions of particles to prepare thin solid films of low microfiltration, by dip-coating or slip-casting. We also propose an original method for the production of thin layers of TinO2n-1 (n to be defined) by sol-gel route followed by a thermal treatment to obtain ultra or nanofiltration active layers. After optimization, those materials have shown their efficiency towards the degradation of bio-refractory compounds such as pharmaceutics (Paracetamol) when used as electrochemical reactive membranes either in static (beaker) or in dynamic mode (filtration pilot). The next step will focus on the coupling of the anodic oxidation and the baromembranar filtration processes using the reactive developed membranes. From first results, this technology appears really promising for the treatment of bio-refractory pollutants in water. This thesis was financially supported by the National Research Agency (NRA) within the framework of the ECO-TS program, the CElectrON project.