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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Micropolluants issus de l'activité domestique dans les eaux urbaines et leur devenir en station d'épuration / Occurrence of some household micropollutants in urban wastewater and their fate in wastewater treatment plant

Pasquini, Laure 23 May 2013 (has links)
Ce travail a permis d'acquérir de nouvelles connaissances sur la micropollution issue de l'activité domestique. Un état des lieux a été réalisé sur la présence de certains micropolluants dans les eaux usées (dans les phases liquide et solide) de deux zones urbaines, résidentielle et mixte (habitats, hôpital, administrations), et dans deux stations d'épuration (STEP) biologiques. Les micropolluants étudiés ont été choisis selon leurs usages et en fonction de leurs propriétés physico-chimiques afin de mieux appréhender leur répartition entre les phases liquides et solides. Dans un premier temps, les méthodes d'extraction et d'analyse des micropolluants dans les matrices liquides (eau usée et eau traitée) et solides (matières en suspension et boue) ont été développées et validées. Les prélèvements d'eaux usées dans les égouts des deux zones urbaines ont mis en évidence différents usages de certains composés en fonction de la zone urbaine et de la saison (été ou hiver). Les mesures des concentrations en micropolluants en entrée et en sortie de STEP dans les eaux et les boues ont permis d'évaluer leurs rendements d'élimination et ont révélé une différence d'efficacité entre les deux STEP biologiques. Une étude statistique a montré qu'il existe des corrélations entre les concentrations en micropolluants et en macropolluants (DCO, ammonium, et turbidité) en entrée et en sortie de chacune des STEP étudiées. L'effet des micropolluants sur l'activité bactérienne a été examiné en conditions de laboratoire par des tests de toxicité sur Escherichia coli et par des expériences sur la biomasse de STEP en réacteur batch / This work allowed to acquire new knowledge on micropollution issued from household activities. The occurrence of some micropollutants in urban wastewater (liquid and solid phases) of two urban areas, residential and mixed (houses, hospital, administrations), and in two biological wastewater treatment plants (WWTPs) was assessed. The studied micropollutants were chosen according to use and as function of their physical and chemical properties in order to consider their partitioning between liquid and solid phases. Firstly, the methods for the extraction and the analysis of micropollutants in liquid and solid matrices (wastewater and treated water, suspended matter and sludge) were developed and validated. Wastewater sampling in the sewers of the two urban catchments showed some differences of the use of certain compounds according to the catchment and to the season (summer or winter). Measurements of micropollutant concentrations at the inlet and outlet of the plants, on water and sludge, allowed to assess their removal yields and revealed a difference of efficiency of the two biological WWTPs. A statistical treatment showed that there are some correlations between concentrations of micro and macropollutants (COD, ammonium and turbidity) at the inlet and at the outlet of each studied WWTPs. The effect of the target micropollutants on bacterial activity was evaluated under laboratory conditions, by toxicity tests on Escherichia coli, and by experiments on biological sludge in batch reactors
2

Processos microbiológicos e composição da matéria orgânica relacionados à eutrofização de uma lagoa costeira hipersalina, L.Araruama, RJ

Guerra, Leandro Viana 22 May 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-05-22T17:32:38Z No. of bitstreams: 1 DISSERTAÇÃO LEANDRO V.G..pdf: 1206910 bytes, checksum: d288e295aca8fbcbcdb1c961d22a8d96 (MD5) / Made available in DSpace on 2017-05-22T17:32:38Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO LEANDRO V.G..pdf: 1206910 bytes, checksum: d288e295aca8fbcbcdb1c961d22a8d96 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / Lagoa hipersalina de Araruama - RJ, nas últimas décadas, vem sofrendo uma ocupação desordenada de sua bacia de drenagem e o conseq üente aporte de matéria orgânica (M.O.) proveniente de esgoto doméstico, alterando drasticamente seu estado trófico, de oligo para hipertr ófico. O presente trabalho pr etende avaliar a composição matéria orgânica e os processos micr obiológicos na Lagoa de Araruama (RJ) e relacionar às condições hipertróficas at uais. Neste sentido, foram considerados eventos distintos, tais como período chuv oso, seco e marés (vazante e enchente). Os locais de amostragem da co luna d’água e sedimento foram selecionados para caracterizar o aporte fluvial – estação Ar aruama (AR), a ciclagem interna – estação São Pedro da Aldeia (SP) e as trocas com o oceano – estação Cabo Frio (CF). A elevada produção primária encontrada (concentração média de clorofila: 450 μ g.L -1 ) e as baixas concentrações das formas nitrogenadas na coluna d’água (NO 2 , NO 3 e NH 4 ), indicam consumo pelo fitoplâncton. Fo ram encontradas elevadas concentrações de carbono orgânico dissolvido (média de 17,5mgC.L -1 ), refletindo numa elevada taxa respiratória (média de 2,08 μ MO 2 .L -1 .h -1 ). As concentrações de biopolímeros foram elevadas no sedimento, principalmente li pídios e carboidratos (2,99 e 2,57mg.g -1 , respectivamente), apresentando a relação [lipídios]>[carboidratos]>[proteínas], diferindo ao descrito pela li teratura para o hemisfério norte. O carbono orgânico estocado nos sedimentos da lagoa apresentou valores médios de 5,5%, C/N de 10,4 e δ 13 C (‰) e δ 15 N (‰) de -14,8 e 6,21, respectivam ente. Os valores em geral apontam para uma mistura de fontes ao carbono depositado nos se dimentos. A proporção relativa entre os esteróis pesqui sados demonstrou uma predominância de estigmasterol na maioria das amostras, que poder ia ter como fonte o fitoplâncton uma vez que sua relação com as plantas vascula res não é válida para um sistema com poucos rios. O coprostanol apresentou elevadas concentrações em AR (média de 263 μ g.g -1 ), sendo encontrado em menor escala em Cabo Frio e São Pedro, e se apresentou como melhor indicador de es goto em ambiente hipersalino que os coliformes termotolerantes. A biomassa e atividades bacterianas no sedimento (metabólica e enzimática) apresentara m-se elevadas, evidenciando a intensa ciclagem da M.O. neste co mpartimento e indicando que a lagoa poderá retornar à melhores condições em curto ou médio praz o, caso sejam adotadas medidas efetivas para sua recuperação / ABSTRACT The hypersaline lagoon of Araruama - RJ is suffering, in the last decades, disordered occupation of its drainage basin and consequent contribution of M.O. originating from domestic sewage, altering drastically your trophic characteristics, from oligo to hypertrophic. The present work intends to evaluate the organic matter composition and the microbial processes in the Araruama Lagoon (R J) and to relate to the current hypertrophic conditions. Thus, di fferent events were considered, such as rainy, dry and tide (low and high) periods. The sites for water column and sediment sampling were selected to characterize the fluvial contri bution in Araruama stat ion (AR), the intern cycling - São Pedro da Aldeia station (SP) and the exchanges with the ocean - Cabo Frio station (CF). The high prim ary production found (chlorophyll: 450 μ g.L -1 ) and the reduced concentrations of the nitrogen forms in the water column (NO 2 , NO 3 and NH 4 ) indicate phytoplankton consumption. High c oncentrations of dissolved organic carbon were observed (average of 17.5mgC.L -1 ), resulting in a high re spiratory rate (average of 2.08 μ MO 2 .L -1 .h -1 ). The biopolymer concentrations were high in the sediment, mostly lipids and carbohydrates (2.9 and 2.57mg.g -1 , respectively), presenting the relationship lipids>carbohydrates>proteins, which differs fr om what is described by the literature for the Northern Hemisphere. The organic carbon stocked in the lagoon’s sediments presented medium values of 5,5%, 10,4 for C/N a nd -14.8‰ and 6.21‰ for δ 13 C and δ 15 N, respectively. Generally, those results indicate a mixture of sources for the deposited carbon in the sedi ments. The relative propor tion among the researched sterols demonstrated a predominanc e of stigmasterol in most of the samples, probably coming from phytoplankton. Despite of this compound are commonly related to vascular plants the absence of a high amount of rivers in the drainage basin turn this source without importance. Coprostanol wa s present in high concentrations at AR station (average of 263 μ g.g -1 ), but it was also found in sm all scale at Cabo Frio and less at São Pedro, and it seems to be a better sewage indicator at the hypersaline environment than the termotolerant coliforms. The bacterial biomass and activities in the sediment (metabolic and enzymatic) were high, evidencing the intense cycling of organic matter in this compartment and indica ting that the lagoon can return to better conditions in short or medium period, if e ffective programs for its recovery are adopted
3

Mainstream Deammonification process monitoring by bacterial activity tests

Carranza Muñoz, Andrea January 2020 (has links)
Deammonification is a widely used technology for side stream treatment with rich ammonium streams at relatively high temperatures, such as, the reject water coming from dewatering units in treatment of digested sludge and industrial wastewaters. The deammonification process has lower operational costs than conventional systems, consumes less energy, enables the increase of biogas production and it is easy to implement. However, this technology has not yet been applied in full- scale mainstream treatment due to its restrictions in coping with high C/N ratios, low temperatures, and the need for post-treatment processes. These conditions are allegedly negative to the growth and performance of anammox bacteria affecting the bacterial groups’ behavior in the process. This master thesis project aimed to evaluate the feasibility of using deammonification to remove nitrogen from mainstream wastewater, which was studied by monitoring the bacterial activity in a pilot scale reactor. The different bacterial groups involved (AOB, NOB, heterotrophs, and denitrifiers) were monitored by weekly measuring their activity in batch activity tests. The results allowed the evaluation of different operational scenarios and their impact by following up on the changes in the bacterial competition. The study was conducted for six months in a single-stage IFAS (integrated fixed-film activated sludge) pilot-scale reactor located in Stockholm and fed with pretreated (with a UASB) municipal wastewater. The different operational scenarios involved changes in temperature, aeration patterns, DO concentration, SRT, and HRT. The adjustment of these features was done in the interest of promoting AOB and anammox bacterial growth, leading to an improvement of the deammonification efficiency in future studies. However, the chosen operational conditions were to enhance bacterial competition and facilitate its visualization, not to maximize nitrogen removal. Thus, the most suitable scenario found during this study included DO concentration of 1.5 mg/L with 10 aeration-20 non-aeration pattern and ensured nitrogen removal rates within normal values while allowing the monitoring of all the bacterial groups. TN removal reached a value above 50% and NH4-N above 95%, whereas nitrogen Removal Rate (NRR) increased to 30g/N/m3-d and the system had an overall nitrogen removal efficiency of 75%. Nevertheless, it was proven that in the right environment, the necessary bacterial groups can be selectively accumulated and successfully perform deammonification and reduce nitrogen levels in mainstream wastewater. / Deammonifikation är en välanvänd teknik för rening av sidoströmmar med höga ammoniumkoncentrationer vid relativt hög temperatur, som till exempel rejektvatten från avvattning av rötslam eller industriellt avloppsvatten. Deammonifikationsprocessen har lägre driftkostnad än konventionella reningsprocesser, förbrukar mindre energi samt möjliggör högre biogasproduktion samtidigt som processen är enkel att implementera. Reningstekniken har dock ännu inte tillämpats i fullskala för rening av huvudströmmen på grund av den höga C/N-kvoten och de låga vattentemperaturerna i kommunalt avloppsvatten samt behovet av efterbehandling. Detta anses ha en negativ inverkan på anammoxbakteriernas tillväxthastighet och funktion vilket påverkar bakteriegruppens beteende i processen. Syftet med detta examensarbete var att utvärdera om det är praktiskt genomförbart att använda deammonifikation för att rena kväve från kommunalt avloppsvatten, vilket följdes upp genom att studera bakterieaktiviteten i en pilotskalereaktor. De involverade bakteriegrupperna (AOB, NOB, heterotrofer och denitrifierare) övervakades genom att mäta den mikrobiella aktiviteten varje vecka med hjälp av batch-tester. Resultaten användes till att utvärdera olika driftstrategier och deras effekt genom att följa förändringarna i mikrobiell aktivitet hos de konkurrerande bakteriegrupperna. Studien genomfördes i Stockholm under sex månader i en enstegs-IFAS-pilotskalereaktor (integrerad process med biofilm på fast bärarmaterial och aktivslam) som matades med kommunalt avloppsvatten som förbehandlats i en UASB-reaktor. De olika driftstrategierna omfattade olika temperaturer, luftningsstrategier, syrekoncentrationer, slamåldrar och hydrauliska uppehållstider. Syftet med driftstrategierna var att främja AOB- och anammoxbakteriers tillväxt för att i framtida studier kunna erhålla en förbättrad deammonifikationsprocess. Syftet i denna studie var dock i första hand att förbättra den bakteriella konkurrensen och göra den lättare att mäta, inte att uppnå bästa möjliga kväverening. Den driftstrategi som gav bäst resultat i denna studie innebar att hålla en syrehalt på 1,5 mg/l med 10 minuter luftning följt av 20 minuter utan luftning vilket säkerställde en normal kväveavskiljning och samtidigt möjliggjorde övervakning av samtliga fyra bakteriegrupper. Totalkväveavskiljningen var över 50 % och ammoniumavskiljningen över 95 % medan kvävereningsaktiviteten ökade till 30 g N/m3-d och systemet hade en övergripande effektivitet på 75 %. Studien visade att under rätt förutsättningar kan de nödvändiga bakteriegrupperna selekteras fram och deammonifikation av kommunalt avloppsvatten kan utföras på ett framgångsrikt sätt.
4

Avaliação da relação entre indicadores microbiológicos de toxicidade e a biodisponibilidade de metais em um ecossistema costeiro (Baía de Sepetiba – RJ)

Rosa, Thiago Dias Lopes 18 September 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-09-18T18:23:01Z No. of bitstreams: 1 DISSERTAÇÃO DE MESTRADO - THIAGO DIAS LOPES DA ROSA.pdf: 1856868 bytes, checksum: 24f79a23cf37a8161ea8b1930ad99eb2 (MD5) / Made available in DSpace on 2017-09-18T18:23:01Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO DE MESTRADO - THIAGO DIAS LOPES DA ROSA.pdf: 1856868 bytes, checksum: 24f79a23cf37a8161ea8b1930ad99eb2 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / Atualmente, pouco se sabe sobre as possíveis relações entre as concentrações das formas biodisponíveis de metais e os biomarcadores microbiológicos de toxicidade. Este estudo teve como objetivo avaliar a relação entre os indicadores geoquímicos e microbiológicos de biodisponibilidade e toxicidade de metais em sedimentos da região do Saco do Engenho (Baía de Sepetiba, RJ). O fracionamento geoquímico de Cd, Zn, Pb e Cu, através de uma extração seqüencial (BCR de 3 etapas), e 3 indicadores microbiológicos de toxicidade (biomarcadores enzimáticos, demanda energética bacteriana e biomassa) foram avaliados em amostras de sedimentos coletados na Baía de Sepetiba, na região próxima ao Porto de Itaguaí e ao Saco do Engenho. Um bioensaio de ressuspensão de sedimento também foi realizado no qual foram avaliados os mesmos parâmetros microbiológicos além do pH, oxigênio dissolvido, temperatura e a concentração de metais dissolvidos. Nas amostras de sedimento, em geral, as concentrações de metais estavam predominantemente na forma oxidada, associados hidróxidos de Fe e Mn. As concentrações máximas de metais obtidas pela extração seqüencial foram observadas próximas ao Saco do Engenho, atingindo 22 mg.kg-1 de Cd, 3855 mg.kg-1 de Zn, 20 mg.kg-1 de Pb e 18 mg.kg-1 de Cu. Esta região ainda possui uma das principais fontes de Cd e Zn da baía. O total (somatório) das concentrações extraídas pelo método BCR de 3 etapas e a demanda energética bacteriana correlacionaram-se significativamente e foram considerados como os melhores indicadores da biodisponibilidade e toxicidade de metais utilizados. No bioensaio a maior degradação da matéria orgânica, via enzimas esterases, pela atividade bacteriana e as maiores concentrações de metais dissolvidos coincidiram em 192 horas, sugerindo que a comunidade bacteriana influenciou mais a remobilização de metais para fase dissolvida do que as variações físico-químicas do meio. Neste experimento, os indicadores microbiológicos de toxicidade foram limitados quando as concentrações de metais biodisponiveis atingiram níveis letais. Desta forma foi possível concluir que marcadores geoquímicos e microbiológicos são limitados quando aplicados individualmente na avaliação de impactos causados pela contaminação ambiental por metais. / The possible relations between metal bioavailable forms and microbiological indicartors of toxicity are currently poorly understood. This study aims to evaluate the relationship between geochemical and microbiological indicators of metal toxicity in sediments from Saco do Engenho (Sepetiba Bay, Brazil). The geochemical partitioning of Cd, Zn, Pb and Cu (following the BCR method) and toxicity indicators (enzymatic biomarkers, bacterial energetic demand and bacterial biomass) were evaluated in bottom sediments and in a sediment resuspension bioassay. In the bioassay, these variables were also evaluated, besides pH, dissolved oxygen, temperature and dissolved metal concentrations. Sediment samples generally presented trace metals in the oxidized form (associated with Fe and Mn oxides). Maximum trace metal concentrations were found near Saco do Engenho (22 mg kg-1 Cd, 3855 mg kg-1 Zn, 20 mg kg-1 Pb and 18 mg kg-1 Cu), indicating that it still is a major source of Cd and Zn to the bay. The sums of BCR method phases extracted for each metal and the bacterial energetic demand presented a significant positive correlation and were considered as the better indicators of metal bioavailability and toxicity. In the bioassay, the higher activity of the esterase enzyme and metal concentration peaks coincided at 192 h of resuspension, suggesting that bacterial activity influenced metal mobilization to dissolved phase in a greater extent than physicochemical variability. In such experiment, the microbiological indicators were limited when bioavailable metals reach lethal levels. Therefore, it was concluded that geochemical and microbiological markers are limited when applied individually to evaluate metal pollution impacts
5

Evaluation of the mechanisms of trace elements transport (Pb, Rare Earth Elements,... ) and the elemental and isotopic fractionation (Ca and Sr) at the interface water-soil-plant / Évaluation des mécanismes de transport des éléments traces (Pb, REE, ...) et du fractionnement des rapports élémentaires et isotopiques (Ca et Sr) à l'interface eau, sol, plante

Gangloff, Sophie 28 January 2016 (has links)
Ce travail est axé sur l’étude d’un profil de sol et des solutions de sol prélevés sur une parcelle expérimentale couvertes d’épicéas. Tous ces échantillons proviennent du Bassin Versant du Strengbach (Observatoire HydroGéochimique de l’Environnement – OHGE), ont été échantillonnés à différentes profondeurs (5, 10, 30 et 60 cm) et durant la période comprise entre 2009 et 2013.Les caractérisations des extraits des sols par spectroscopie Infra-Rouge ont permis de mettre en évidence les modifications des groupements fonctionnels organiques avec la profondeur et que ces modifications ont une forte incidence sur le comportement des cations (majeurs et traces) dans le sol. Des expérimentations d’ultra-filtration ont permis d’identifier les flux colloïdaux et dissous du carbone organique ainsi que ceux des éléments majeurs et traces présents dans les solutions de sol. L’utilisation conjointe des traceurs isotopiques (87Sr/86Sr et δ44/40Ca) et chimiques (Terres Rares) ont mis en évidence des processus ayant lieu aux interfaces eau-sol-plante, comme le prélèvement racinaire ou l’altération des sols. / This work is focused on the study of a profile of soil and soil solutions collected on an experimental plot covered with spruce. All these samples come from the watershed of the Strengbach (environment - OHGE Hydrogeochimique Observatory), were sampled at different depths (5, 10, 30 and 60 cm) and during the period between 2009 and 2013. Characterizations of soil extracts by infrared spectroscopy allowed to highlight changes in the organic functional groups with depth and that these changes have a significant impact on the behaviour of the cations (major and trace) in the soil. Ultrafiltration experiments helped to identify flows of colloidal and dissolved organic carbon as well as those of the major and trace-element present in soil solutions. The joint use of isotope tracers (87Sr / 86Sr and δ44 / 40 Ca) and chemical (Rare Earth Elements) have highlighted processes taking place at the water-soil-plant interface, as the uptake by root or soil alteration.

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