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An analysis of <i>sae</i>Ogino, Megumi January 1990 (has links)
No description available.
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Rôle de l'énonciation dans l'analyse linguistique du nom propre / à venirCormier, Agathe 24 June 2011 (has links)
L’objectif de ce travail est de montrer que l’énonciation joue un rôle essentiel dans l’institution et l’interprétation des noms propres.La définition du nom propre comme signe linguistique contient, outre le signifiant et le signifié, le référent, c’est-à-dire un renvoi à l’actualisation du signe dans le discours, ce qui explique la marginalité du nom propre dans la linguistique structuraliste ; d’autre part, le sens d’un nom propre – “x appelé N par S” – est défini comme une relation de dénomination entre un individu (x) et un nom propre (N) exprimée par un sujet énonciateur (S), qui dépend d’un acte de nomination associant tel nom à tel individu et initiant ainsi l’usage du nom.La valeur des variables x, N et S est déterminée pour une occurrence de nom propre donnée, en fonction de la situation d’énonciation et d’un acte de nomination logiquement préalable. La notion linguistique de personne permet précisément de rendre compte de ce rapport entre référent du nom propre et énonciation et du rôle du contexte dans l’interprétation du nom propre. Elle se révèle notamment indispensable pour l’analyse du nom propre hors phrase qui se caractérise à la fois par son indépendance vis-à-vis du cotexte et par une forte dépendance au contexte non verbal. La comparaison des noms propres avec les embrayeurs et déictiques, traditionnellement définis comme impliquant un renvoi à la situation d’énonciation, conduit également à considérer que l’interprétation d’un nom propre est entièrement déterminée par le contexte et en particulier par l’identité des personnes de l’énonciation. / The purpose of this work is to show that acts of utterance play an important role in the institution and the interpretation of proper names.The definition of proper names as signs contains, in addition to the signifiant and the signifié, the referent, that is to say a reference to the actualization of the sign in discourse. That is why proper names are on the margins of structuralist linguistics. Moreover, the meaning of a proper name – “x named N by S” – is defined as a denominative relation between an individual (x) and a proper name (N) expressed by an utterer (S), depending on an act of naming which associates a name with an individual and initiates the use of this name.The value of the variables x, N and S is defined for a given occurrence of a proper name according to the situation of utterance and to a logically prior act of naming. The linguistic notion of person precisely allows to account for this relation between the referent of the proper name and the act of utterance and for the role of the context in the interpretation of the proper name. This notion appears to be essential for analysing out of sentence proper names which are linguistic context-free but extralinguistic context-dependent. The comparison between proper names and shifters and indexicals, which are traditionally defined as involving a reference to the speech situation, leads also to consider that the interpretation of a proper name is entirely determined by the context and especially by the identity of the enunciative persons.
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Contribution de la connaissance du nom des lettres à l’apprentissage du son des lettres : Etudes chez les prélecteurs francophones / Letter-name knowledge contribution to letter-sound learning : Study with French prereadersBouchière, Blandine 13 December 2011 (has links)
Cette thèse présente un ensemble d’études examinant l’influence de la connaissance du nom des lettres sur l’apprentissage et la connaissance du son des lettres. Deux études sont consacrées à la place de la connaissance de la forme des lettres dans la relation entre nom et son des lettres. Les études ont été menées auprès de prélecteurs francophones âgés de 3 à 6 ans et scolarisés en école maternelle. L’objectif de la première étude (Etude 1) était de décrire la connaissance du nom des lettres avec l’âge et d’identifier des facteurs d’apprentissage. Les résultats ont révélé une influence de la fréquence, du prénom, de l’ordre alphabétique, du type et de la structure du nom des lettres. Le nom des lettres de type èC ou VC (e.g., F, L…) ou non acrophonique était mieux connu que le nom des lettres de type Cé .ou CV (e.g., B, D…) ou de type MR (C, G…). L’étude 2 examine l’influence de la structure du nom des lettres sur la connaissance du nom et du son des lettres. Les résultats ont montré la même influence de la structure du nom des lettres sur la connaissance du nom que dans l’étude 1. L’influence de la structure du nom des lettres sur la connaissance du son des lettres est différente : le son des lettres de type Cé ou CV ou acrophoniques était mieux connu que le son des lettres èC ou VC et MR. Ces résultats suggèrent que le meilleur apprentissage du son des lettres de type Cé n’est pas dû à une familiarité générale. Le chapitre 3 de la thèse présente une étude qui examine l’effet de facilitation nom-son. Le son des lettres a été enseigné systématiquement à des enfants qui se distinguaient par leur connaissance du nom des lettres. Les enfants connaisseurs du nom des lettres apprenaient plus facilement le son des lettres que les enfants non connaisseurs du nom. Un effet de la structure du nom des lettres chez les enfants connaisseur du nom montrait que le son des lettres dont le nom contient le son de la lettre (CV et VC) était mieux appris que le son des lettres dont le nom ne contient pas le son de la lettre (MR). La connaissance du nom des lettres et la conscience phonologique contribuaient à une part de variance spécifique de l’apprentissage du son des lettres, avec une contribution supérieure de la connaissance du nom des lettres. Les études du chapitre 4 examinent le développement de la sensibilité au son des lettres à partir de la connaissance du nom des lettres dans des tâches d’identification de syllabes (Etude 4), de lettres (Etude 5) et de phonèmes (Etude 6). Les enfants identifiaient au-delà du hasard les syllabes, lettres et phonèmes. Un effet de la structure du nom des lettres est apparu : les lettres dont le son est relié au nom (CV et VC) étaient mieux identifiées que les lettres dont le son n’est pas ou pas clairement relié au nom (MR). Le chapitre 5 (Etude 7) explore les liens entre connaissance du nom des lettres et connaissance de la forme des lettres à partir de tâches de catégorisation de lettres, de discrimination de la forme des lettres et de reconnaissance immédiate des lettres. Les enfants connaisseurs du nom des lettres étaient également de meilleurs connaisseurs de la forme des lettres. Ils catégorisaient, discriminaient et reconnaissaient mieux et plus vite les formes de lettre que les enfants non connaisseurs du nom. Enfin, le dernier chapitre présente une étude expérimentale (Etude 8) qui examine l’influence de la connaissance préalable de la forme des lettres sur l’apprentissage du nom et du son des lettres. L’étude n’a pas révélé d’influence de la connaissance préalable de la forme des lettres sur l’apprentissage des associations forme-nom et forme-son. L’ensemble des études apporte des informations originales sur l’effet de facilitation nom-son et sur l’influence de la connaissance de la forme des lettres au sein de cette relation. / This thesis introduces studies which examined the influence of letter-name knowledge to letter-sound knowledge and learning. Two studies were designed to examine the role of letter-shape knowledge in the relation between letter-name and letter-sound. These studies were conducted with French prereaders aged from 3 to 6 years old. The aim of the first study (Study 1) was to describe letter-name knowledge and to identify learning factors. Results revealed an influence of letter frequency, of first name, of alphabetical order and of letter-name structure. Letter names of èC or VC (e.g., F, L…) which correspond to non-acrophonic letter-name structure, were better known than letter-name of Cé or CV (e.g., B, D) or MR (C, G…). Study 2 examined the influence of letter-name structure to letter-name and letter-sound knowledge. Results showed the same influence of letter-name structure on letter-name knowledge as in Study 1. The influence of letter-name structure was different on letter-sound knowledge: The sounds of Cé or CV, or acrophonic letter-name structure, were better known than the sounds of èC or VC and MR letter-name structure. These results suggest that the learning of Cé sounds is not due to general familiarity. Chapter 3 introduces a study that examined the name-to-sound facilitation effect. Children differing in their letter-name knowledge were systematically taught letter-sound. Children with letter-name knowledge learned more easily letter sounds than did children with no letter-name knowledge. A letter-name structure effect was found for children with letter-name knowledge , indicating that the sound of CV and VC letter-name structure was better learned than the sound of MR letter-name structure. Letter-name knowledge and phonological awareness contributed to a specific part of variance in letter-sound learning, with a higher contribution of letter-name knowledge. The studies of chapter 4 examined the development of letter-sound sensitivity from letter-name knowledge using syllable identification (Study 4), letter identification (Study 5) and phoneme identification tasks (Study 6). Syllables, letters and phonemes were identified beyond chance level by children. A letter-name structure effect appeared: CV and VC letters were better identified than MR letters. Chapter 5 (Study 7) explored the links between letter-name knowledge and letter-shape knowledge using letter categorization tasks, letter-shape discrimination tasks and letter immediate recognition tasks. Children with letter-name knowledge had the best letter-shape knowledge. They categorized, discriminated and recognized shapes more exactly and more rapidly than did children with no letter-name knowledge. Finally, the last chapter introduced an experimental study (Study 8) designed to examine the influence of prior letter-shape knowledge on both letter-name and letter-sound learning. This study revealed no influence of prior letter-shape knowledge on either letter-name learning or letter-sound learning. As a whole, these studies provide new information concerning the name-to-sound facilitation effect and the influence of letter-shape knowledge in this relation.
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Utvärdering av processen vid Hofors vattenverk med avseende på avskiljning av NOM – fällning och membranfilterteknik / Evaluation of the process at Hofors water treatment plant with respect to the separation of NOM - flocculation and membrane filtration technologyTirén Ström, Julia January 2016 (has links)
De senaste årtiondena har en ökning av naturligt organiskt material (NOM) observerats i ytvatten i norra Europa och Nordamerika. NOM i vattnet innebär utmaningar för vattenverk som använder ytvatten i dricksvattenproduktionen då det kan ge upphov till lukt, smak och färg och svårigheter i driften. För att åtgärda och förebygga problemen behövs mer kunskap om NOM samt hur kvantiteten och sammansättningen förändras i olika reningsprocesser. Vid Hofors vattenverk används råvatten från sjön Hyen i dricksvattenproduktionen. Driftstörningar upplevs i perioder då råvattnets färgtal (mått på halten NOM) är högt. Därför undersöktes det hur väl den nuvarande reningsprocessen vid Hofors vattenverk fungerar med avseende på avskiljning av NOM samt vilken typ av NOM som avskiljs. Resultaten jämfördes med pilotförsök med direktfällning på ultrafiltermembran för att se om detta kan ge bättre avskiljning. Olika analysmetoder, absorbans, fluorescens och mätning av löst organiskt kol (DOC), användes för att avgöra kvantitet och karaktär på NOM i vattenproverna. Även eventuell förekomst av trend i råvattnets färgtal undersöktes. Likt i många andra ytvatten har färgtalet i Hyen har ökat de senaste åren (1997-2015). Råvattnet är svårfällt och innehåller en blandning av olika NOM-fraktioner. Huvudsakligen avskiljs humuslikt, alloktont NOM i Hofors vattenverk. Avskiljningen var störst i första reningssteget, direktfällning på sandfilter. Förändringen i efterföljande reningssteg, kolfilter samt desinfektions- och pH-höjande steg, var dock svår att bestämma till följd av mycket små förändringar och motsägande analysresultat. Tre ultrafiltermembranförsök gav liknande avskiljningsresultat som sandfilter, men i två av fallen är det troligt att igensättning av membranen spelade in. Det krävs ytterligare försök för att säkert uttala sig om huruvida ultrafiltermembran är en teknik som är lämplig att använda vid Hofors vattenverk i framtiden för avskiljning av NOM. / In recent decades, an increase in natural organic matter (NOM) has been observed in surface waters in Northern Europe and North America. NOM in the water poses challenges for water treatment plants (WTP) using surface water in the drinking water production. It can cause odor, taste and color of the water and cause difficulties in the treatment process. To prevent all these problems, more information about NOM and how the quantity and composition changes in various treatment processes is needed. At Hofors WTP, raw water from the lake Hyen is used in the production of drinking water. Disruptions in running the process have been experienced in periods when the raw water color (measure of the NOM content) has been high. In this thesis, it was investigated how well the current treatment process at Hofors WTP works with respect to the separation of NOM and what type of NOM that is separated. The results were compared with pilot tests with direct filtration using an ultrafilter membrane to see if this can provide better separation. Various analytical methods as absorbance, fluorescence and measurement of dissolved organic carbon (DOC) were used to quantify and determine the composition of NOM in the water samples. It was also examined whether there is a trend in the raw water color. As in many other surface waters the color of the water has increased in Hyen in recent years (1997-2015). The raw water contains a mixture of different NOM fractions and the character indicates difficulties in removing DOC by coagulation and flocculation. It is primarily the humic like, allochtonous NOM that is separated in the treatment process with the greatest separation in the first treatment step, direct filtration with sand filter. What happens in the subsequent treatment steps, carbon filter, disinfection and pH-raising step, was however unclear due to small changes and inconsistent analysis results. Three experiments with ultrafilter membrane yielded similar results as sand filters, but in two of the cases it is likely that clogging of the membranes contributed. Further membrane pilot tests are needed to be sure whether ultrafilter membrane is a is suitable technique to use at Hofors WTP in the future for separation of NOM.
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L'acquisition de l'ellipse du nom chez les enfants unilingues francophonesBourdua-Roy, Èvelyne January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
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Interakce mezi proteiny a huminovými látkami při koagulaci / Interactions between proteins and humic substances during coagulationNovotná, Kateřina January 2015 (has links)
This diploma thesis is focused on coagulation of humic substances (HS) and BSA (Bovine Serum Albumin) protein which was chosen as a representative of proteins contained in AOM (Algal Organic Matter). Additionally, possible interactions between these compounds were also investigated. It was found that the optimal dosage of coagulant is much higher for HS compared to BSA. The best removal of both HS and BSA was reached in slightly acidic pH range and it is attributed mainly to charge neutralization and adsorption mechanisms. The maximum removal rate was 70 % for humic substances and 80 % for BSA. The results show that BSA has a positive effect on coagulation of HS (resulting in a lower coagulant demand) and vice versa while BSA was removed more efficiently than HS. The existence of interactions between BSA and humic substantces during coagulation was demonstrated in certain pH ranges and it can occur even without the presence of coagulant. These interactions are highly dependent on pH that determines charge properties (and hence reactivity) of organic matters. Finally, the comparison of BSA and cyanobacterial proteins shows that their behavior during coagulation is similar. Consequently, BSA can be used as a model compound representing AOM proteins, especially their high molecular weight fraction....
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Le champ notionnel des noms de mémoire « Easter rising » et « Bloody sunday » dans la littérature irlandaise d'expression anglaise du xxème et du xxie siècle / The conceptual field of the memory names "easter rising" and "bloody sunday" in Anglo-Irish literature of XX and XXI centuriesKhmelevskaya, Inna 10 December 2015 (has links)
Сette thèse est consacrée à l'étude des noms de mémoire « Easter rising » et « Bloody sunday » et les constellations onomastiques qui les entourent, dans la littérature irlandaise d’expression anglaise du XXe et XXIe siècle. La recherche est menée sur trois axes : historique, linguistique et littéraire. Cette thèse démontre, à travers l'analyse des contextes littéraires des noms de mémoire et de leur mise en discours, les fonctions que ces derniers peuvent remplir dans le discours littéraire irlandais. Elle s’interroge sur les valeurs culturelles et symboliques qu'ils sont aptes à véhiculer, aux mécanismes du développement d'un nom de mémoire,à l'interrelation entre un événement historique, son image et le (ou les) discours élaboré(s) sur cet événement et sur ces acteurs. Elle se concentre particulièrement sur les cadres discursifs (verbaux) et prédiscursifs (tacites) que ces noms de mémoires activent en discours, et aux moyens que l’écrivain utilise pour déstabiliser ces cadres ou en sortir. / The study focuses on « memory names » « Easter Rising » and « Bloody Sunday » and on onomastic fields buildt around them in Anglo-Irish contemporary fiction. This researсh is conducted at the crossroads of history, linguistics and literary analysis. It aims to show the functions they can fill in Irish literary discourse through an analysis of the contexts surrounding the « memory names » and the ways they are expressed. The cultural and symbolical values that they convey, the mecanisms of development of a memory name, as well as the interrelation between an historical event, its representation and (or) the discours about the event and its actors are examined in detail. The study focuses in particular on discursive and non-verbal ideological frames conveyed by the « memory names », and on the means that a writer uses to deconstruct these frames or to move outside the framework.
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Influence of pH and NOM on Sorption of Phenols onto Aquifer MaterialAmiri, Fariba 02 March 2005 (has links) (PDF)
Geosorption processes play an important role as retardation mechanism in subsurface transport of organic water constituents. Geosorption behaviour of Ionisable Hydrophobic Organic compounds (IHOCs) especially influence of dissolved natural organic materials on their sorption coefficients is poorly investigated. In this study influence of pH and NOM on the sorption of three different phenols (2-methyl-4,6-dinitrophenol, 2,4,6-trichlorophenol and pentachlorophenol) on a natural sandy aquifer material collected from a bank filtration site was studied in flow through column experiments. In first step the sorption coefficients of investigated phenols from NOM-free solutions with different pH values were determined. Single as well as multi (mixed) solutes experiments confirmed that there was no competition effect among the phenols investigated. An increasing sorption/retardation was observed with decreasing pH. A linear model was used to resolve the apparent sorption coefficient into an ionised species and neutral species component. This model allows a prediction of apparent sorption coefficients for any pH value. Analysis of data also revealed that the anion of 2-M-4,6-DNP show no significant sorption and a simple model based on the neutral form sorption coefficient was useful in predicting the apparent sorption coefficient over the entire pH range investigated. For 2,4,6-TCP and PCP, the anion sorption is much lower than that of the neutral species but cannot be neglected completely. For PCP, the anion sorption is even as high as the sorption of neutral 2,4,6-TCP. Thus for such hydrophobic phenols prediction of sorption based only on the partitioning of non-dissociated species may lead to an error, especially at high pH values (&gt; pKa), where ionised form is present predominantly. On the other hand prediction of sorption based on the partitioning of non-dissociated species is useful at pH &lt; pKa or in cases where the anion sorption can be neglected. The advantage of this prediction is that it allows predicting the pH-dependent sorption only on the basis of LFER correlations. It was shown that the organic carbon normalized sorption coefficients of the neutral forms of the phenols can be predicted better by solubility based regression correlations than by n-octanol-water partition coefficient based correlations. In second step the apparent sorption coefficients of investigated phenols from NOM-containing solutions (mixed solution of phenols dissolved in natural river water) with different pH values were determined; the sorption coefficients obtained from this step were compared with the results of the first step examinations. Analysis of data revealed that binding of 2-M-4,6-DNP by dissolved humic substances (DHS) reduces the sorption coefficient significantly. In contrast to it, the sorption of the more hydrophobic chlorinated phenols was not affected by DHS. A strong reduction of sorption onto aquifer material caused by complex formation with DHS was also observed for a second nitrophenol (2,4-DNP) and seems to be typically for nitrophenols. A combined sorption and complex formation model was proposed which could be used successfully to describe the effect of pH and NOM concentration on sorption reduction and to estimate binding constants. The binding constant found for 2-M-4,6-DNP is much higher than those reported by Ohlenbusch and Frimmel, 2001, for chlorophenols associated with Aldrich humic acid. This can be interpreted as a result of specific interactions between the nitrophenol and DHS. This phenomenon may cause an increase of the amount of nitrophenols, which can be transported with the groundwater flow and has to be considered in transport modelling, especially in cases where pH is lower than pKa. The models developed here are a useful tool to describe the influence of pH and NOM on geosorption processes and to estimate the Kd values which have to be used in transport models.
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Optimizing Conditions of Coagulation for Removal of Natural Organic Matter (NOM) : Comparison of Removal Efficiency of NOM When Using Bench-Scale Inline Coagulation Over Ultrafiltration and Classical Jar Tests / Optimering av koaguleringsförhållanden för avskiljning av naturligt organiskt material (NOM) : Jämförelse av avskiljningseffektivitet för NOM vid användning av inline-koagulering tillsammans med ultrafiltrering i bänkskala samt klassisk testningOveisy, Hiwa January 2023 (has links)
Abstract The removal of Natural Organic Matter (NOM) from water supplies is crucial for the provision of clean, safe drinking water. Lab-scale experiments have been extensively utilized in water treatment facilities to optimize this process. The most used lab-scale method is known as jar test. However, with emerging membrane filtration, lab-scale inline coagulation has been recently utilized to mimic the inline coagulation over membrane filtration in water treatment plants (WTPs). This study aims to compare the jar test with inline coagulation micro pilot methods from different aspects, including the NOM removal, time, and cost needed for each process. Three case studies were conducted using different water sources in Sweden: Katrineholm, Mälaren, and Mjörn. In the experiments conducted to find the optimal NOM removal condition, the inline coagulation micro pilot method outperforms the jar test in terms of removal efficiency. In the Katrineholm case, the micro pilot method with a coagulant dosage of 4.5mg/l Al at pH 6.7 achieved removal efficiencies of 63% for fluorescent dissolved organic matter (fDOM), whereas the jar test showed 60% for fDOM but with a significantly higher coagulant dosage (7mg/l) . In the Mälaren case, the micro pilot method using a dosage of 2.5mg/l Al at pH 6.4 yielded removal efficiencies of 62% for UV254, absorbing organic matter and the jar test showed almost the same removal (64%) for UV254 but with a significantly higher coagulant dosage. Finally, in the Mjörn case, the micro pilot method with a coagulant dosage of 3.5mg/l Al at a pH of 6.6 resulted in removal efficiencies of 76% for UV254, the jar test also resulted in 76% for UV254 at the same pH level. While the micro pilot method showed better removal efficiencies, it consumed more chemicals compared to the jar test. The micro pilot experiments required higher volumes of coagulant and additional chemical backwashing after each set of experiments. In contrast, the jar test method used lesser quantities of coagulant and chemicals due to the smaller scale of the experiments. The findings of this study highlight the superiority of the inline coagulation micro pilot method over the jar test for optimizing NOM removal in water treatment processes. Despite the jar test being quicker and more cost-effective, it often required higher coagulant dosages to achieve comparable results. This was mainly because jar test demands heavy and large enough flocs to be removed from the water. Conversely, the micro pilot method, although more time-consuming and costly, provided more precise coagulant dosage control, resulted in higher removal efficiencies, and offered a more comprehensive understanding of the coagulation process. This is achieved by using a sensor called EXO sensor, which allows for immediate monitoring of the treatment results.
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Carbon Filters for Drinking Water Treatment – How Flow Rate and Empty Bed Contact Time Influence the Performance / Kolfilter för dricksvattenrening - Hur flödeshastighet och uppehållstid påverkar reningenBäckström Nilsson, Wilma January 2021 (has links)
Dricksvatten är en essentiell del av ett hållbart samhälle. Därför är det viktigt att säkerställa säkert dricksvatten genom fungerande vattenreningsverk. En viktig förorening att behandla är NOM, som i sig är ofarligt men som kan producera farliga föroreningar. En teknik som används för behandling av NOM är kolfiltrering. Hur ökad flödeshastighet och ökad kontakttid påverkade kolfiltrens effektivitet undersöktes vid dricksvattenreningsverket Norrvatten. De undersökta parametrarna var partiklar, ultraviolett absorbans vid 254 nm, turbiditet, konduktivitet, fluorescent löst organiskt material, totalt organiskt kol, kemisk syreförbrukning, odlingsbara mikroorganismer och lukt. Tre kolfilter studerades vid olika flödeshastigheter; 190, 220, 250 och 280 L/s under ett dygn var. Samtidigt hade två filter ökad kontakttid på 60 och 76 % under sex veckor, medan ett filter fortsatte med den vanliga flödeshastigheten på 190 L/s. Utgående vatten från filtren analyserades för att se om dessa ändringar hade någon effekt på vattenreningen. Denna preliminära studie fann ingen signifikant effekt på kolfiltreringens rening på grund av ökad flödeshastighet eller uppehållstid. Detta kan vara en indikation på att kolfiltreringen kan hantera en framtida flödesökning och därmed vara en väsentlig del av en framtida expansionen av vattenreningsverket. De tecken som visade på att kolfiltren påverkades av ökningen av flödeshastigheter kunde förklaras av fluktuationer i inkommande vatten och skillnader mellan de olika filtren. I framtiden bör effekten av inkommande vatten studeras i detalj. En mer ingående analys av både inkommande och utgående vatten till kolfiltren bör utföras, där provtagning sker oftare för att bättre förstå fluktuationerna i inkommande föroreningskoncentrationer. Dessutom bör testerna upprepas för att se hur reningen skiljer sig från dag till dag. Hur kolfiltren hanterar ökade flödeshastigheter över längre tidsperioder bör också undersökas vidare. / Drinking water is an essential part of a sustainable society. In the future, the demand for drinking water will increase and contaminants in the water sources are also predicted to increase. Therefore, it is essential to ensure safe drinking water through functioning drinking water treatment plants (DWTPs). One important contaminant to treat is natural organic matter (NOM), which is harmless in itself but can produce harmful products. One technique to use for treating NOM is carbon filters (CFs). The effect of increased flow rate and increased empty bed contact time (EBCT) on the CF efficiency was investigated at a DWTP. The investigated parameters were particles, ultraviolet absorbance at 254 nm, turbidity, conductivity, cultivable microorganisms, fluorescent dissolved organic matter, total organic carbon, chemical oxygen demand, and odour. Three CFs were studied at different flow rates; 190, 220, 250, and 280 L/s for 24 hours each. Additionally, two filters had increased EBCT of 60 and 76 %, while one filter continued with the regular flow rate of 190 L/s for six weeks. Outgoing water from the filters was analysed to see if the change had any effect on the DWTP. This preliminary study did not find any significant effect on the CF treatment caused by increased flow rate or EBCT. This could be an indication that the CFs can handle a future increase in flow rate and thus be an essential part of a future expansion of the DWTP. The indications of CFs being affected by the increase in flow rates for some of the parameters could be explained by fluctuations in incoming water or differences between the separate filters. In the future, a more thorough analysis of both incoming and outgoing water to the CFs should be done, where sampling occurs more frequently to better understand the fluctuations in incoming contaminant concentrations. The measurements should also be repeated to see how the treatment differs from day to day. How the CFs handle increased flow rates over longer time periods should also be investigated further.
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