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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.
71

A study of pharmaceutical residues in wastewater from small municipalities in Northern Sweden : E-peroxone as a complementary tertiary removal technique

Hägglund, Mathias January 2021 (has links)
The conventional treatment processes used in Swedish sewage treatment plants (STPs) are not designed to remove micropollutants such as pharmaceuticals and biocides. This leads to STPs being a major source of pharmaceuticals in the environment including surface waters, coastal waters, and groundwaters all over the world. The occurrence of these compounds combined with their adverse ecological effects makes them problematic. This study aims to investigate the removal of pharmaceuticals and biocides from six conventional STPs from small municipalities in Northern Sweden. It also aims to evaluate the suitability and potential of an advanced treatment process called electro-peroxone (E-peroxone) as an additional tertiary treatment step complementing the current STPs configurations, through batch experiments. The removal of pharmaceuticals and biocides in the studied STPs showed great variability. The occurrence of pharmaceuticals was mainly in line with previous research apart from caffeine and paracetamol concentrations. Several pharmaceuticals were detected above their respective critical environmental concentration (CEC) in effluent wastewaters. The removal of pharmaceuticals was heavily influenced by paracetamol. When excluding paracetamol, the total removal of pharmaceuticals ranged from -23% to 80% in the conventional processes. After E-peroxone treatment, removals, excluding paracetamol, ranged from 61% to 93%, and no average effluent concentrations exceeded their respective CEC. In this study, E-peroxone was conducted in not optimized batch-experiments due to time constraints, but still with promising results. In a full-scale application, water matrix specific optimizing should be performed. Therefore, the removal efficiencies of pharmaceutical residues by the E-peroxone process in a plant-specific configuration would most likely be significantly increased.
72

Consumption-based estimation of discharge of human-used antibiotics from sewage treatment plants (STPs) to the aquatic environment and risk assessment / 消費量をもとにしたヒト用抗生物質の下水処理場から水環境への流出量の推定とリスク評価

MIAO, JIA 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23869号 / 工博第4956号 / 新制||工||1774(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 藤原 拓, 准教授 西村 文武, 講師 中田 典秀 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
73

Regeneration of Lanthanum Following Precipitation of Phosphates from Waste-Waters

Wasserlauf, Mark 03 1900 (has links)
<p> Government programs now underway in Ontario aim at removing phosphates from waste-waters at sewage treatment plants. At present, removal of phosphates is commonly accomplished by chemical precipitation with lime, alum, or iron. Lanthanum, a rare earth element, has been found to be an effective precipitant of phosphates. If lanthanum precipitate can be collected, and the lanthanum then regenerated so that it could be recycled for further phosphate precipitation, a very advantageous alternative to the above schemes would result.</p> <p> In this study, phosphates were precipitated from both distilled water and secondary effluent using lanthanum. For the two cases, a regeneration scheme for lanthanum was examined. The basic regeneration reactions were carried out to evaluate the kinetics and equilibria for different ratios of reactants and different reaction temperatures. Techniques for phase separation of reacted reagents were studied. Process design calculations were carried out to obtain order of magnitude figures for amounts and costs of chemicals required, amounts of sludge produced, and reactor sizes.</p> / Thesis / Master of Engineering (MEngr)
74

Biological Nitrogen Removal in a Gravity Flow Biomass Concentrator Reactor

Scott, Daniel 20 April 2011 (has links)
No description available.
75

Legitimacy and justice on the verge of deterioration : A case study of Swedish local efforts to reduce eutrophication

Vafa, Amir January 2021 (has links)
Eutrophication is one of the major threats to the marine environment in the Baltic Sea. The human pressure on the sea by nutrient input from agriculture, industry, public sewage facility and small sewage treatment plants causes excessive algal blooms leading to oxygen depleted seabed and an ecosystem out of balance. The objective of this study is to investigate how local legitimacy and fairness is addressed in the multilevel and complex issue of reducing Baltic Sea eutrophication. The main results show that there is a great challenge and uncertainty in dealing with the problem of eutrophication. Furthermore, there is an unfair distribution of costs and responsibilities related to wastewater treatment in the municipal planning documents and nearly total exclusion of the individual property owners from participating in the decision-making processes related to the expansion plans for public sewage facility. This in turn risks the legitimacy and the democratic aspects of the plans. Previous studies related to public and simple sewage plants have investigated different issues related to the legislation and practical planning as possible reasons for a sluggish progress in the measures to reduce nutrient discharges to the sea. However, the fairness aspects and the participatory processes of the plans have not been studied. The implications of this study are to invite to a more inclusive and fair planning process with the use of alternative solutions to the compulsory expansion of public sewage facility. Modifications in the legislation to include economic instruments creating incentives for the property owners can be a way of increasing participation and thus the legitimacy of the system.
76

Avaliação da microfiltração tangencial como alternativa de tratamento avançado de efluente gerado em sistema de tratamento de esgoto sanitário constituído de reator UASB (Upflow Anaerobic Sludge Blanket) seguido de tanque de aeração / The evaluation of crossflow microfiltration as an alternative for advanced treatment of effluent generated in a system of sewage treatment composed by a UASB (Upflow Anaerobic Sludge Blanket) reactor followed by an aeration tank

Vidal, Carlos Magno de Sousa 10 March 2006 (has links)
A proposta desta pesquisa consistiu na avaliação da microfiltração tangencial para o tratamento avançado de efluente gerado em sistema de tratamento de esgoto sanitário constituído de reator UASB (Upflow Anaerobic Sludge Blanket) seguido de tanque de aeração. Neste trabalho foram avaliados métodos de limpeza física (retrolavagem com ar comprimido) e química (ácida e básica) das membranas, bem como análise comparativa da colmatação e do desempenho de membranas de tamanhos de poro de 0,2 e 1,0 'mü'm, quando aplicadas ao pós-tratamento de efluentes do tanque de aeração em diferentes concentrações de SST. Foram contemplados ainda estudos de desinfecção de efluentes da microfiltração por radiação UV e aplicação do processo de coagulação antecedendo a microfiltração tangencial. Os experimentos foram realizados em unidade piloto com membranas tubulares de polipropileno com área efetiva de filtração de 0,036 'M POT.2'. Constatou-se que a limpeza física foi essencial para obtenção de maiores valores de fluxo de permeado na unidade de microfiltração. A limpeza química das membranas por solução básica foi mais eficiente quando comparada a limpeza ácida. Foram obtidos melhores resultados com a membrana de 0,2 'mü'm, quando comparada a membrana de 1 'mü'm, a qual apresentou intensa colmatação interna de seus poros. Para membrana de 0,2 'mü'm obteve-se permeado de excelente qualidade microbiológica (E.Coli < 1 UFC/100 mL e Colifagos < 16 UFP/100 mL), bem como valores de turbidez inferiores a 1,46 uT e remoção praticamente completa de SST. A prévia coagulação das amostras de licor misto do tanque de aeração contribuiu para obtenção de maiores taxas e melhor remoção de P-'PO IND.4'POT.3-' e DQOt na unidade de microfiltração. Para dosagem de 40 mg/L de cloreto férrico obteve-se a maior taxa média (139,7 L/'M POT.2'.h), concentrações residuais de P-'PO IND.4'POT.3-' inferiores a 1,4 mgP/L e DQOt menor que 33 mg/L. A radiação UV permitiu inativação completa de E.Coli e Colifagos das amostras de permeado. Concluiu-se que a microfiltração tangencial apresentou grande potencialidade para ser aplicada no tratamento avançado de efluente gerado em sistema de tratamento de esgoto sanitário constituído de reator UASB (Upflow Anerobic Sludge Blanket) seguido de tanque de aeração. / The proposal of this research was to evaluate the crossflow microfiltration as an alternative for an advanced treatment of effluent generated in a system of sewage treatment composed by a UASB (Upflow Anaerobic Sludge Blanket) reactor followed by an aeration tank. This work aimed to evaluate the membranes physical cleaning methods (backwashing with compressed air) and the chemical ones (acid and basic), as well as the comparative analysis between the fouling event and the 0,2 and 1,0 'mü'm pore size membranes performance, when applied to the aeration tank effluents in a post-treatment stage at TSS different concentrations. Studies for microfiltration effluents disinfection by UV radiation and the application of the coagulation process preceding the crossflow microfiltration were also developed. The experiments were performed in a pilot unit with polypropylene tubular membranes with 0.036 'M POT.2' of effective filtration area. It was verified that the physical cleaning was essential to the attainment of higher permeate flux values in the microfiltration unit. The chemical cleaning of the membranes through basic solution was more efficient when compared to their acid cleaning. Better results were attained when the 0,2 'mü'm membrane was employed in comparison with the 1 'mü'm membrane, which presented intense internal blocking of its pores. It was attained an excellent microbiological quality (E.Coli < 1 FCU/100 mL and Coliphages < 16 FPU/100 mL) for the 0,2 'mü'm membrane, as well as turbidity levels under 1,46 uT and almost total removal of TSS. The previous mixed liquor samples coagulation of the aeration tank contributed to the attainment of higher rates and better removal of P-'PO IND.4'POT.3-' and CODt in the microfiltration unit. It was attained, for the ferric chloride 40 mg/L dosage, the higher mean rate (139,7 L/'M POT.2'.h), P-'PO IND.4'POT.3-' remaining concentrations under 1,4 mgP/L and CODt lesser than 33 mg/L. The UV radiation allowed the complete inactivation of E.Coli and Coliphages from the permeate samples. It was concluded that the crossflow microfiltration presents great possibilities of application in the advanced treatment of effluent generated in a system of sewage treatment composed by a UASB (Upflow Anaerobic Sludge Blanket) reactor followed by an aeration tank.
77

Estudo de casos de wetlands construídos descentralizados na região do Vale do Sinos e Serra gaúcha / Study of cases of decentralized constructed wetlands in the region of the Sinos Valley and Rio Grande do Sul's Sierra

Timm, Jeferson Müller 20 March 2015 (has links)
Submitted by Maicon Juliano Schmidt (maicons) on 2015-06-05T13:18:40Z No. of bitstreams: 1 Jeferson Müller Timm.pdf: 22708335 bytes, checksum: 0e6767a349a961cd7763953f3abd4e6a (MD5) / Made available in DSpace on 2015-06-05T13:18:40Z (GMT). No. of bitstreams: 1 Jeferson Müller Timm.pdf: 22708335 bytes, checksum: 0e6767a349a961cd7763953f3abd4e6a (MD5) Previous issue date: 2015-03-20 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / Na busca por sistemas de tratamento de esgotos domésticos que atendam os princípios do desenvolvimento sustentável, os Wetlands Construídos apresentam-se como tecnologias de interesse. Esse trabalho avalia o desempenho de seis diferentes configurações de Wetlands Construídos descentralizados no tratamento de efluentes domésticos na região do Vale do Sinos e Serra gaúcha. Foram estudados dois wetlands de fluxo horizontal (WFH) comunitários, três wetlands de fluxo vertical (WFV) residenciais e um wetland de pré-tratamento com macrófitas flutuantes (WMF) Comunitário. Este trabalho avalia o desempenho dos sistemas, a eficiência na remoção da carga orgânica e desinfecção do esgoto frente à legislação, clima, cenário e condições de operação. Após 5 meses de monitoramento, todos os sistemas se mostraram eficientes na remoção da carga orgânica e turbidez, atendendo a legislação brasileira e apresentando concentrações médias na saída das unidades para DBO de 26,3; 12, 5 e 134,0 mg/L nos WFH, WFV e WMF, respectivamente. Em termos de DQO os resultados médios na saída das unidades foram de 160, 5 mg/L; 156, 5 mg/L e 134,0 mg/ L para os WFH, WFV e WMF respectivamente. Os WFH e WFV apresentaram remoção superior a 70% da carga orgânica mesmo nos sistemas saturados. Os WFV atenderam às necessidades de remoção da carga de nutrientes e apresentaram médias de 0,6 mg/L e remoção de 72% para fósforo total e 7,8 mg/L e 7,7 mg/L para nitrogênio total e amoniacal, respectivamente e remoção superior a 90% da carga nitrogenada. Os WFH não atenderam a legislação na remoção de nutrientes, diminuindo em média 39% da carga de fósforo, 52% de nitrogênio total e 37% de nitrogênio amoniacal, com médias de 5,8; 52,9 e 50,1 mg/L respectivamente no efluente tratado. Somente os WV1 e WV3 atenderam a legislação na desinfecção de E.coli e somente o WV3 para Coliformes Totais. O decréscimo de Coliformes totais foi de 73% nos WFH e 87% nos WFV, com médias na saída das unidades de 2,97E+04 e 3,38E+04 NMP/100 mL, respectivamente, nos WFH e WFV. Em termos de E. coli o decréscimo médio foi de 90% nos WFH e 84% nos WFV, com resultados de 2,86E+04 e 2,58E+03 nas saídas das respectivas unidades estudadas. Os fatores climáticos indicaram influência na dinâmica de funcionamento dos wetlands. Todos os WFV se mostraram efetivos para o fim a que se destinam e se mostraram adequados como sistemas de tratamento de esgoto on site. Os WFH evidenciaram a necessidade de um correto dimensionamento, acompanhamento técnico e manutenção dos sistemas coletivos. / In the search for treatment systems for domestic sewage that attend to principles of sustainable development, the Constructed Wetlands present itself as technologies of interest. This study evaluates the performance of six different configurations of decentralised constructed wetlands in domestic effluent treatment in the region of Sinos Valley and Rio Grande do Sul's Sierra. There were two community systems of horizontal flow (HFWs), three residential systems of vertical flow (VFWs) and a community system of pre-treatment with floating macrophytes (FMW). This work evaluates the performance of the systems, the efficiency in the removal of organic load and disinfection of sewage relative to legislation, climate, scenery and operation conditions. After 5 months of monitoring, all systems were shown to be effective in the removal of organic load and turbidity, attending to brazilian legislation and presenting mean concentrations at the outlet of the units for BOD of 26,3; 12,5 and 134,0 mg/L in HFWs, VFWs and FMW, respectively. In terms of COD average results in the outlet of the units were 160,5 mg/L; 156,5 mg/L and 234,2 mg/L for the HFWs, VFWs and FMW respectively. The HFWs and VFWs presented removing greater than 70% of organic load, even in saturated systems. The VFWs reached the needs of removing of nutrients load and presented an average of 0,6 mg/L and removal of 72% for total phosphorus, and 7,8 mg/L and 7,7 mg/L for total and ammoniacal nitrogen, respectively, removing over than 90% of nitrogen load. The HFWs operated with overload of application and did not attending the legislation in the removal of nutrients, decreasing on means of 39% of phosphorus load, 52% of total nitrogen and 37% of ammoniacal nitrogen, with averages of 5,8; 52,9 and 50,1 mg/L respectively in the treated effluent. Only the VW1 and VW3 attended to the legislation for the disinfection of E. coli and only the VW3 for total coliform. The mean removal of total coliforms was 73% in HFWs and 87% in VFWs, with means at the outlet of the units of 2,97E+04 e 3,38E+04 NMP/100 mL, respectively, in HFWs and VFWs. In terms of E. coli the average efficiency was 90% in HFWs and 84% in VFWs, with results of 2,86E+04 e 2,58E+03 in the respective outputs of the studied units. The climatic factors indicated influence in dynamic operation of wetlands. All VFWs were effective for the purpose for which it is intended and showed itself appropriate as systems of sewage treatment on site. The HFWs showed the need for a correct dimensioning, technical monitoring and maintenance of collective systems.
78

Avaliação temporal de indicadores de qualidade da água em microbacias do rio Piracicaba / Temporal evaluation of indicators of water quality in watersheds of the Piracicaba River

Vidas, Natássia Bonini 25 April 2014 (has links)
A unidade de estudo denominada bacia hidrográfica pode ser considerada um importante agente de integração entre processos naturais e antrópicos. Através do estudo do metabolismo dos corpos hídricos, pode-se conhecer fatores que implicam nas alterações funcionais destes processos. Seguindo nesse contexto, pode-se citar a bacia do rio Piracicaba, um autêntico modelo de bacia desenvolvida, com problemas ambientais típicos de áreas impactadas. Estudos desenvolvidos pelo Projeto PiraCena, entre os anos de 1994 e 2001, confirmaram que as emissões de esgotos domésticos e industriais e as mudanças no uso da terra, contribuíram para transformações drásticas no seu metabolismo. Entretanto, desde o encerramento deste projeto, recursos financeiros gerenciados pelos Comitês das Bacias Hidrográficas dos Rios Piracicaba, Capivari e Jundiaí foram aplicados, principalmente, em obras de saneamento como coleta e tratamento de esgotos domésticos. Assim, este estudo buscou avaliar durante doze meses a evolução de parâmetros físicos e químicos da água, visando conhecer como o processo de urbanização ainda afeta o metabolismo do rio e como os lançamentos de efluentes provenientes de estações de tratamento de esgoto interferem na composição química e no metabolismo aquático de ribeirões da bacia do rio Piracicaba, situados em regiões densamente ocupadas. Os resultados obtidos neste estudo foram ainda comparados com resultados publicados pelo Projeto PiraCena, com o objetivo de identificar possíveis melhorias na qualidade das águas desses ribeirões. Foi possível observar através dos resultados obtidos que apesar de todo esforço que tem sido feito visando a melhoria da qualidade da água dos corpos hídricos da bacia do rio Piracicaba, a deterioração ainda é continua. Além disso, foi possível reforçar os resultados encontrados pelo projeto PiraCena, uma vez que apesar de ter havido um aumento considerável no volume de esgoto doméstico tratado, esse tratamento não tem surtido efeito significativo sobre a qualidade da água de vários ribeirões da bacia. Portanto, é imperiosa uma avaliação detalhada sobre o funcionamento das estações de tratamento de esgoto para que as mesmas cumpram o seu papel que é prover a sociedade uma água de qualidade, assegurando ao mesmo tempo a integridade biótica da mesma. / The unit of study called watershed can be considered an important agent of integration between natural and anthropogenic processes. Studying the metabolism of water bodies, it is possible to know which factors are involved in the functional changes of these processes. In this context, it is inserted the Piracicaba river basin, an authentic model of developed basin with typical environmental issues of impacted areas. Studies conducted by PiraCena Project, between 1994 and 2001, confirmed that emissions from domestic and industrial sewage and changes in land use have contributed to drastic changes in its metabolism. However, since the end of the project, funds managed by the Watershed Committee of Piracicaba, Capivari and Jundiaí Watersheds were applied, mainly in sanitation, such as collection and treatment of domestic wastewater. Thus, this study aimed to evaluate the evolution of physical and chemical water parameters, during twelve months, trying to understand how the process of urbanization still affects the metabolism of the river and how the discharge of effluents from sewage treatment stations interfere in the chemical composition and the aquatic metabolism of streams that belong to the Piracicaba river basin, located in densely populated regions. The results obtained in this study were compared with previous results published by PiraCena Project, with the goal of identifying possible improvements at the water quality of these streams. It was observed from the results obtained that, despite every effort that has been made, aiming the improvement of the water quality at the water bodies of the Piracicaba river basin, the deterioration is still present. Moreover, it was possible to reinforce the results found by PiraCena project, since there was a considerable increase in the treated domestic sewage volume, but the effect of this treatment has not been significant to the quality of some streams of the basin. Therefore, the necessity of a detailed evaluation about the functioning of the sewage treatment stations is imperative, so they can continue providing the society with water of quality, while ensuring biotic integrity.
79

Estudo comparativo entre oito sistemas de lagoas de estabilização da região noroeste do Estado de São Paulo / Comparative study of eight systems of stabilization ponds in the northwestern region of São Paulo

Gomes, João Luiz Cais da Silva 10 April 2002 (has links)
Este trabalho comparou oito lagoas de estabilização da região Noroeste do Estado de São Paulo, que tratam esgotos predominantemente sanitários de Coroados, Lourdes, Planalto, Zacarias, Alto Alegre, Pongaí, Irapuã e Adolfo, cidades pequenas, com no máximo 5500 habitantes (1700 ligações), onde os quatro primeiros sistemas são compostos apenas por lagoas facultativas primárias e os quatro últimos por lagoas anaeróbias e lagoas facultativas secundárias. Vinte e cinco variáveis físicas, químicas e biológicas foram analisadas em amostras compostas coletadas entre 24/05/2000 e 03/10/2000. A análise da batimetria efetuada fornece indicações de prazos para a remoção do lodo do fundo das lagoas. As taxas de acúmulo de lodo médias obtidas para as lagoas anaeróbias e facultativas primárias foram de 0,07 e 0,14 m3/hab.ano, respectivamente. O pH do efluente das lagoas anaeróbias e das facultativas foi em média 6,6 e 7,4. Nas lagoas anaeróbias observou-se alta remoção de sólidos suspensos e de Demanda Bioquímica de Oxigênio (DBO) com eficiência geral média de 64% e 61% respectivamente. Os sistemas não atenderam plenamente à legislação no tocante a eficiência de remoção de DBO de 80%, porém o valor médio encontrado para os oito sistemas foi de 78%, bastante próximo do exigido. Sugere-se para a região, para eficiência de remoção de DBO de 80%, lagoas anaeróbias com tempo de detenção de 5 dias e para as lagoas facultativas primárias e secundárias tempos de detenção de 25 e 15 dias respectivamente, e taxas de aplicação superficial de 140 e 130 kg DBO/ha.dia, respectivamente. Não foi atingido o limite máximo de 1000 coliformes fecais por 100 ml, obtendo-se média geral de remoção de 97,40% inferindo-se que há necessidade de um processo de tratamento complementar para a remoção de microrganismos. Não observou-se correlação entre eficiência do sistema e relação comprimento/largura das lagoas. Constatou-se maus odores mesmo na ausência de concentrações detectáveis de sulfeto. A remoção média geral de amônio (NH4+), nitrogênio total, fosfato total dissolvido e fósforo total foi de 31%, 12%, 24% e 27% respectivamente nos sistemas estudados. / The present work compared the performance of eight stabilization ponds in the Northwest region of São Paulo state, that treat predominantly the domestic sewage from eight small cities with a maximum of 5000 inhabitants (1700 links): Coroados, Lourdes, Planalto, Zacarias, Alto Alegre, Pongaí, Trapuã and Adolfo. The first four systems are made of four primary facultative ponds and the last four by anaerobic ponds and secondary facultative ponds. A total of twenty-five chemical, physical and biological variables were analyzed in integrated samples collected between 24/05/2000 and 03/10/2000. The bathymetric analysis performed has indicated deadlines for sludge removal from the stabilization pond bottom. Mean sludge accumulation rates o btained for anaerobic and primary facultative ponds were 0.07 and 0.14 m3/inhabt.year, respectively. Effluents from anaerobic and facultative ponds had a mean pH of 6.6 and 7.4. In anaerobic ponds a righ rate of suspended solids removal was found and the Biochemical Oxygen Demand (BOD) had an overall general efficiency of 64% and 61%, respectively. The systems did not completely attend the present legislation in respect to a BOD removal of 80%, as required, however the mean value for the eight systems monitored was 78%, very close to the established limit. It is therefore suggested that for this region, in order to attain the removal efficiency of 80% anaerobic ponds should have a residence time of 5 days and the primary and secondary facultative ones should have residence times of 25 and 15 days respectively, coupled to loading rates of 140 and 170 Kg BOD/ha.day respectively. Also, the maximum limit of 1000 fecal coliforms per 100 ml was not reached, and in general there was a mean removal efficiency of 97.40%, indicating that an additional treatment process needs to be implemented for a successful removal of coliforms. No correlation was found between the removal efficiency and morphometry (length/weight) pond characteristics. Bad smell was present even in the absence of detectable amounts of sulfide. The mean efficiency for the removal of ammonium (NH4+), total nitrogen, total dissolved phosphorus and total phosphorus were 31%, 12%, 24%, and 27% respectively, among the systems studied.
80

Analyse des résidus de drogues illicites dans les eaux de stations d’épuration : rendements d’élimination et évaluation de l’impact écotoxique. Contribution à l’estimation des consommations / Analysis of illicit drug residues in sewage water treatment plants : removal efficiencies, evaluation of the ecotoxicological impact and estimation of consumption

Néfau, Thomas 16 January 2014 (has links)
Les drogues illicites consommées sont éliminées sous forme inchangée ou métabolisée dans les urines et/ou les fèces et rejoignent le réseau d’égout. La quantification de ces produits d’élimination dans les eaux usées présente un double intérêt : d’une part, permettre d’évaluer la contamination des milieux naturels par ces composés et d’autre part, contribuer à l’estimation de la consommation de drogues illicites dans une population dépendant d’un même bassin collecteur des eaux usées urbaines. Des méthodes analytiques adaptées à la charge organique complexe des eaux usées ont été développées et validées pour évaluer les niveaux de contamination des affluents et effluents de 26 stations d’épuration en France pour dix-sept composés (drogues illicites et métabolites). Les résultats d’analyses ont permis d’évaluer les taux d’élimination de ces composés en fonction des technologies de traitement utilisées dans les stations d’épuration. Les concentrations mesurées dans les affluents ont été utilisées pour estimer les consommations de drogues illicites par un calcul en retour et ont montré des différences qualitatives et quantitatives de consommation de stupéfiants entre zones urbaines en France métropolitaine et en Outre-mer. Dans une dernière partie, des études de toxicologie sur un modèle bactérien et des études comportementales sur un modèle animal ont été conduites à des niveaux de concentrations proches des teneurs relevées en eau de surface et aucun effet notable n’a été observé. / Illicit drugs are metabolized or eliminated unchanged in the urine and/or feces then join the sewer system. The quantification of these products in wastewater disposal has two advantages: firstly, to assess the contamination of the environment and also contribute to the estimation of illicit drug consumption in a catchment. Analytical methods adapted to the complex organic load of wastewater have been developed and validated to assess the levels of contamination of influents and effluents from 26 sewage treatment plants in France for seventeen compounds (illicit drugs and metabolites). The results of the analysis were used to evaluate the elimination of these compounds depending on the treatment technologies used in wastewater treatment plants. Concentrations in the influent were used to estimate the illicit drug consumption by back calculation and showed qualitative and quantitative differences of drug use among urban areas in metropolitan France and overseas. In the last part, toxicology studies on a bacterial model and behavioural studies with an animal model have been conducted with concentration levels close to the levels found in surface water and no significant effect was observed.

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