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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.
121

Error detection in wastewater treatment plants using mass balances

Karlsson, Maja January 2018 (has links)
Process data from wastewater treatment plants are often corrupted by errors. These data provide a basis for operating the plant, therefore effort should be made to improve the data quality. Currently, Stockholm Vatten och Avfall uses a method where they quantitatively verify water flow measurement data by comparing it to water level measurements. In this thesis, an alternative approach based on mass balancing to detect errors was evaluated. The aim was to find, implement and evaluate a mass balance based method to detect and locate errors. The objective was to use this method to corroborate the flow verification method used by Stockholm Vatten och Avfall, and to improve flow data from Bromma Wastewater treatment plant. The chosen method consisted of two major steps, gross error detection and data reconciliation. A case study was performed where the method was tested on both simulated data with known added errors, real process data and finally a case where the suggested method was compared to the flow verification method. The results showed that this method was efficient in detecting a gross error when only one flow measurement was erroneous and that the estimation of the error magnitude was good. However, the suggested method was not useful for corroboration of the flow verification method. With the flow verification method, the flow in one filter basin at the time was examined. The suggested method required the combined flow in all 24 filter basins, which made it difficult to compare the two methods. The method has potential to be valuable for error detection in wastewater treatment plants, and to be used as a live tool to detect gross errors.
122

CARBONATAÇÃO ACELERADA EM CONCRETOS COM ADIÇÃO DE CINZAS DE LODO DE ESTAÇÃO DE TRATAMENTO DE ÁGUA / ACCELERATED CARBONATION IN CONCRETE WITH ADDITION OF WATER TREATMENT PLANT SLUDGE ASHES

Adorna, Diego da Luz 14 July 2016 (has links)
Carbonation is a natural phenomenon for concrete structures and occurs due to the reaction between CO2, which is concentrated in the environment, and Ca(OH)2, which is present in the cementitious matrix. Carbonation reaction reduces the pH of the concrete and causes the destruction of the passivation layer, which surrounds the steel armor, leaving it vulnerable to the process of corrosion. In this study, was investigated the performance against the carbonation of concrete with the addition of water treatment plant sludge ashes, in concentrations of 5%, 10%, 15%, 20%, 25% and 30% replacing Portland cement, as well as a reference blend without mineral admixtures. All mixtures were molded with three w/b ratios (0.35; 0.50 and 0.65) and with two periods of wet cure (three and seven days). Concrete specimens underwent preconditioning according to RILEM TC 116-PCD, targeting the moisture balance (75% ± 2%) in an aerial environment with constant temperature (23° C ± 2° C) and uniform moisture distribution. Afterwards, specimens were forwarded to a carbonation chamber, with humidity (75 ± 2%), temperature (23°C ± 2° C) and CO2 concentration (3%) duly regulated. Specimens were tested after 4, 8, 12 and 16 weeks of CO2 exposure through phenolphthalein spraying, the depths of carbonation is obtained and, therefore, the carbonation coefficients. Results revealed that the incorporation of water treatment plant sludge ashes into concrete leads to increases in its carbonation, in all mixtures investigated. Comparisons with the results for Porosimetry by Mercury Intrusion and Thermogravimetry enable attribute this effect to the microstructural change and decrease of alkalinity of the mixture with addition of sludge ash. Through an analysis of equal resistance, it was found that concrete with addition of sludge ash water treatment are feasible, from the point of view of carbonation's lifespan, only to higher strength levels. / A carbonatação é um fenômeno natural às estruturas de concreto, ocorrendo pela reação entre o CO2, concentrado no ambiente, e o Ca(OH)2, presente na matriz cimentícea. A reação de carbonatação provoca a redução do pH do concreto, causando a destruição da camada passivadora, que envolve a armadura de aço, deixando esta vulnerável ao processo de corrosão. Nesta pesquisa, foi investigado o desempenho, frente à carbonatação, de concretos com adição de cinzas de lodo de estação de tratamento de água, nos teores de 5%, 10%, 15%, 20%, 25% e 30% em substituição ao cimento Portland, bem como uma mistura de referência, sem adições minerais. Todas as misturas foram moldadas com três relações a/agl (0,35; 0,50 e 0,65) e com dois períodos de cura úmida (três e sete dias). Os corpos-de-prova de concreto foram submetidos à um pré-condicionamento, conforme procedimentos sugeridos pela norma RILEM TC 116-PCD, visando o equilíbrio de umidade (75% ± 2%) em um ambiente aéreo com temperatura constante (23°C ± 2°C) e distribuição uniforme de umidade. Posteriormente os corpos-de-prova foram encaminhados para uma câmara de carbonatação, com umidade (75% ± 2%), temperatura (23°C ± 2°C) e concentração de CO2 (3%) devidamente reguladas. Os corpos-de-prova foram ensaiados após 4, 8, 12 e 16 semanas de exposição ao CO2, por meio de aspersão de fenolftaleína, sendo obtidas as profundidades de carbonatação e, com isso, os coeficientes de carbonatação. Os resultados demonstraram que a incorporação de cinzas de lodo de estação de tratamento de água ao concreto acarreta no aumento da carbonatação nos mesmos, para todas as misturas investigadas. Comparações com resultados de Porosimetria por Intrusão de Mercúrio e Termogravimetria permitiram atribuir este efeito às alterações microestruturais e a diminuição da reserva alcalina das misturas com adição de cinzas de lodo. Através de uma análise em igualdade de resistência, constatou-se que os concretos com adição de cinzas de lodo de estação de tratamento de água são viáveis, do ponto de vista da vida útil frente à carbonatação, apenas para níveis de resistência mecânica mais altos.
123

Gestão de resíduo e tecnologia ambiental na fabricação de tijolos solo-cimento

Samson, Bárbara pereira 28 April 2016 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2017-07-14T12:50:22Z No. of bitstreams: 1 arquivototal.pdf: 8841136 bytes, checksum: aaa642f094b0481f15236b39854feb0a (MD5) / Made available in DSpace on 2017-07-14T12:50:22Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 8841136 bytes, checksum: aaa642f094b0481f15236b39854feb0a (MD5) Previous issue date: 2016-04-28 / Currently we have been sought new constructive solutions involving environmental sustainability through the reduction / elimination of waste of raw materials and final products. The reduction of waste has been granted by the rational use of materials and various forms of reuse, for both are studied and developed technologies capable of absorbing this waste. Under the basic sanitation is highlighted waste generated in water treatment plants during the process of purifying plants of water intended for human consumption. This residue is commonly called sludge. For environmental issues, frequent studies point to the incorporation of this waste in construction materials such as conventional bricks and soil cement. Laboratory analyzes were: Fluorescence Xray (XRF) , Chemical Oxygen Demand (COD) , Biochemical Oxygen Demand (BOD), Particle size , Plasticity Index and resistance to simple compression. This the following study aims to evaluate the incorporation of the waste generated in the Water Treatment Plant - Gramame in soil-cement bricks type. The concreteness of research leads to consideration of the incorporation of the waste generated in the Water Treatment Plant - Gramame in low percentages do not affect the strength of soil-cement bricks. This result associated with a considerable concentration of Organic matter. / Atualmente têm-se buscado novas soluções construtivas que envolvam a sustentabilidade ambiental através da diminuição/eliminação de desperdício das matérias-primas e produtos finais. A redução dos desperdícios vem sendo conferida pelo uso racional dos materiais e as diversas formas de reutilização, para tanto são estudadas e desenvolvidas tecnologias capazes de absorver estes resíduos. No âmbito do saneamento básico é destacado o resíduo gerado nas Estações de Tratamento de Água durante o processo de potabilização das águas destinadas para o consumo humano. Comumente este resíduo é chamado de lodo. Para as questões ambientais, estudos frequentes apontam para a incorporação deste resíduo em materiais de construção civil tais como tijolos convencionais e solo-cimento. Desta forma, o seguinte trabalho visa avaliar a incorporação do resíduo gerado na Estação de Tratamento de Água – Gramame em tijolos do tipo solo-cimento. Para que os objetivos pudessem ser alcançados foram determinadas as análises laboratoriais de: Fluorescência de Raio-X (FRX), Demanda Química de Oxigênio (DQO), Demanda Bioquímica de Oxigênio (DBO), Granulometria, Índice de Plasticidade e Resistência a Compressão Simples. A concretude da pesquisa leva a conclusão de que a incorporação do resíduo gerado na Estação de Tratamento de Água – Gramame em baixas porcentagens não prejudica a resistência dos tijolos solo-cimento. Sendo este resultado associado a uma considerável concentração de Matéria Orgânica.
124

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

Natássia Bonini Vidas 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.
125

Desreguladores endÃcrinos presentes em matrizes ambientais: anÃlise por SPE-HPLC e remoÃÃo com argila pilarizada. / EDs present in environmental matrices: analysis by SPE-HPLC and removal with pillared clay.

Carla Bastos Vidal 03 September 2015 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As substÃncias denominadas desreguladores endÃcrinos (DE) sÃo uma categoria recente de poluentes ambientais que interferem nas funÃÃes do sistema endÃcrino, sendo encontradas no meio ambiente em concentraÃÃes na ordem de μg L-1 e ng L-1. Os efluentes de ETEs sÃo importantes fontes de lanÃamento desses compostos no ambiente aquÃtico uma vez que os processos convencionais de tratamento de Ãgua e esgoto nÃo removem totalmente esses micropoluentes. Neste trabalho avaliou-se a eficiÃncia da argila pilarizada utilizando o diÃxido de estanho como agente pilarizante para remoÃÃo de DE (de diferentes classes) em matrizes ambientais. Foi utilizado o planejamento experimental para avaliaÃÃo dos fatores que afetaram o processo adsortivo. Para etapa de otimizaÃÃo do mÃtodo analÃtico anteriormente validado foi estudada a eficiÃncia de trÃs cartuchos SPE comerciais. Foram obtidas concentraÃÃes afluentes, efluentes e eficiÃncias de remoÃÃo em duas estaÃÃes de tratamento de esgotos que operavam em escala real (UASB + cloraÃÃo). Por fim, foram realizados experimentos de adsorÃÃo de DE em sistemas mono e multicomponentes, assim como de regeneraÃÃo do adsorvente. Os cartuchos Oasis e Strata-X mostraram elevada eficiÃncia e capacidade seletiva, entretanto apenas o cartucho Strata-X foi o selecionado neste trabalho, uma vez que o mesmo mostrou maiores valores de recuperaÃÃo (%) de 50 (Sulfamethoxazol); 83 (Trimetoprima); 171 (Diclofenaco); 183 (Estrona); 14 (17β-estradiol) e 82 (Bisfenol-A). O mÃtodo cromatogrÃfico mostrou-se seletivo para todos os compostos estudados, exceto para o hormÃnio estriol. Os valores de limite de quantificaÃÃo (1,28-29,97 ng L-1) e limite de detecÃÃo (0,42-9,89 ng L-1) obtidos neste trabalho foram considerados baixos. A maioria dos valores de recuperaÃÃo encontrados foi menor que 100%. Foi possÃvel observar que o esgosto afluente Ãs ETEs estudadas ainda apresentam em seus efluentes quantidades considerÃveis de DE, com valores mÃdios efluentes entre 21,94-311,79 ng L-1 para ETE Aracapà e 4,41-123,47 ng L-1 para ETE Mondubim, o que evidencia a necessidade de uma etapa de pÃs-tratamento nas ETEs estudadas. Foram encontradas maiores eficiÃncias de tratamento para os compostos bisfenol A (90,8%) e 17α-etinilestradiol (76,6%) na ETE Mondubim. Jà para os compostos sulfametoxazol e estrona foi observado um incremento nos valores efluentes de 18,9 e 28,6%, respectivamente para a ETE AracapÃ. A argila pilarizada mostrou maior capacidade de adsorÃÃo quando comparada à argila natural, devido ao alargamento do espaÃo interlamelar da argila e aumento no volume de mesoporos como comprovado pelas tÃcnicas de caracterizaÃÃo. ApÃs anÃlise dos resultados do planejamento fatorial foi fixado os valores Ãtimos encontrados das variÃveis no processo para compor os estudos de cinÃtica e isoterma de adsorÃÃo, os quais foram Temperatura â 25 ÂC; AgitaÃÃo â 300 rpm; Massa do adsorvente: 300 mg e pH â 3. O estudo cinÃtico indicou tempo de equilÃbrio de 1 hora, sendo o modelo de pseudo-segunda ordem o que melhor se ajustou aos dados. O mecanismo de difusÃo intrapartÃcula nÃo foi a etapa determinante da velocidade e no processo de transferÃncia de massa. A maioria dos compostos DE estudados obteve maior remoÃÃo em sistema multicomponente quando comparados aos estudos monocomponentes. Os dados experimentais de isoterma de adsorÃÃo melhor se ajustaram ao modelo de Freundlich com exceÃÃo aos referentes aos compostos TMP e BPA. Os testes de regeneraÃÃo do adsorvente indicaram significante reduÃÃo da capacidade de adsorÃÃo da argila pilarizada no 2 ciclo de adsorÃÃo para os compostos TMP e BPA, com reduÃÃo de 99,5 e 79,2 %, respectivamente. Para os compostos E2 e E1, a adsorÃÃo foi afetada apÃs o 3 ciclo. / The substances called endocrine disruptors (ED) are a new category of environmental pollutants that interfere in the functions of the endocrine system, being found in the environment at concentrations in the order ug L-1 and L-1 ng. The WWTP effluent release are important sources of such compounds in the aquatic environment since the conventional methods of water treatment and sewage not completely remove these micropollutants. In this study we assessed the efficiency of pillared clay using tin dioxide as an agent for removing pilarizante DE (of different classes) in environmental matrices. Experimental design was used to evaluate the factors affecting the adsorptive process. For optimization step of the previously validated analytical method it was studied the effectiveness of three commercial SPE cartridges. Tributaries concentrations were obtained, effluents and removal efficiencies of two sewage treatment plants operating in full scale (UASB + chlorination). Finally, DE adsorption experiments were performed in single and multicomponent systems as well as regenerating the adsorbent. The Oasis and Strata-X cartridge efficiency showed high and selective ability, however, only Strata-X cartridge was selected in this study, since it showed higher recovery values (%) 50 (Sulfamethoxazol); 83 (Trimethoprim); 171 (diclofenac); 183 (estrone); 14 (17β-estradiol) and 82 (Bisphenol A). The chromatographic method was selective for all compounds studied, except for the hormone estriol. The quantification limit values (1.28 to 29.97 ng L-1) and detection limit (from 0.42 to 9.89 ng L-1) obtained in this study were low. Most of the recovery values was less than 100%. It was observed that the esgosto tributary of the studied WWTPs still present in their waste considerable amounts of DE, with average values of effluents from 21.94 to 311.79 ng L-1 for ETE Aracapà and 4.41 to 123.47 ng L 1 to ETE Mondubim, which highlights the need for a step of post-treatment in the studied WWTPs. They have found greater efficiencies treatment for compounds bisphenol A (90.8%) and 17α-ethinylestradiol (76.6%) ETE Mondubim. As for the compounds sulfamethoxazole and estrone it was observed an increase in effluent values of 18.9 and 28.6% respectively for the ETE AracapÃ. The pillared clay showed higher adsorption capacity compared to the natural clay, due to enlargement of the interlayer space of the clay and increased volume of mesopores as evidenced by the characterization techniques. After analyzing the results of the factorial design was set optimum values of the variables found in the process to make the studies of kinetics and adsorption isotherm, which was temperature - 25  C; Agitation - 300 rpm; Mass of adsorbent: 300 mg and pH - 3. The kinetic study indicated 1 hour equilibration time, with the model of pseudo-second order which best fit to the data. The intraparticle diffusion mechanism was not the determining step of the speed and mass transfer process. The majority of the DE compounds obtained greater removal in multicomponent system when compared to single-component studies. The experimental data better adsorption isotherm set the model Freundlich except to refer to the TMP and BPA compounds. The sorbent regeneration tests indicated a significant reduction in the adsorption capacity of pillared clay in the 2nd adsorption cycle for TMP and compounds BPA, with a reduction of 99.5 and 79.2%, respectively. For E2 and E1 compounds, adsorption was affected after the 3rd cycle.
126

Avaliação das propriedades da argamassa com substituição parcial de cimento por cinza do lodo da estação de tratamento de água da cidade de Manaus

Batalha, Claudionildo Teles 02 March 2012 (has links)
Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-09-30T14:02:28Z No. of bitstreams: 1 Dissertação - Claudionildo Teles Batalha.pdf: 5805065 bytes, checksum: 3edbb62a9308274ff4069328e815f8e8 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-10-02T20:08:35Z (GMT) No. of bitstreams: 1 Dissertação - Claudionildo Teles Batalha.pdf: 5805065 bytes, checksum: 3edbb62a9308274ff4069328e815f8e8 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-10-02T20:40:37Z (GMT) No. of bitstreams: 1 Dissertação - Claudionildo Teles Batalha.pdf: 5805065 bytes, checksum: 3edbb62a9308274ff4069328e815f8e8 (MD5) / Made available in DSpace on 2015-10-02T20:42:01Z (GMT). No. of bitstreams: 1 Dissertação - Claudionildo Teles Batalha.pdf: 5805065 bytes, checksum: 3edbb62a9308274ff4069328e815f8e8 (MD5) Previous issue date: 2012-03-02 / OUTRAS / In this research study was conducted on the production of Portland cement mortar with the use of ash sludge from water treatment plant in the city of Manaus in the partial replacement of Portland cement. The sludge ash obtained after the process of drying, grinding and calcination temperature of 650 ° C, was used as a component in the mixture, partially replacing cement by 5%, 10% and 15% by weight. Tests were performed to obtain the physical and mechanical properties of the cementitious matrix, the influence of ash WTS (CLETO) in the array, testing X-ray diffraction, thermal analysis, axial compressive strength, modulus of elasticity and absorption porosimetry. The results show that the use of CLETO and technically feasible: the compressive strength of mortar with a content of 5% and 15% ash replacing the cement had, at 28 days, statistically equal results compared to the reference mortar. The porosimetry test showed that the ash as well as providing a reduction in consumption of cement in the mix, had worked on refining the pore structure of mortar with 5% CLETO, reducing 15,64% increase in the macropores and mesopores 4% compared to the reference mortar. In capillary absorption test, the mortars had lower rates compared to the reference mortar, confirming the effect of fillers in the matrix CLETO. / Nesta pesquisa foi efetuado estudo sobre a produção de argamassa de cimento Portland com a utilização da cinza do lodo da estação de tratamento de água da cidade de Manaus em substituição parcial ao cimento Portland. A cinza do lodo, obtida após os processos de secagem, moagem e calcinação na temperatura de 650 °C, foi usada como componente da mistura substituindo parcialmente o cimento em 5%, 10% e 15% em massa. Foram efetuados ensaios para obtenção das propriedades físicas e mecânicas da matriz cimentícia, influência da cinza de lodo de ETA (CLETA) na matriz, ensaios de difração de raios X, análise térmica, resistência à compressão axial, módulo de elasticidade, porosimetria e absorção. Os resultados apresentados mostram que o uso da CLETA é viável técnicamente: as resistências à compressão das argamassas com teor de 5% e 15% de cinza substituindo o cimento apresentaram, aos 28 dias, resultados estatísticamente iguais em comparação à argamassa de referência. O ensaio de porosimetria mostrou que a cinza além de proporcionar redução no consumo de cimento na mistura, atuou no refinamento da estrutura de poros da argamassa com 5% de CLETA, reduzindo 15,64% os macroporos e aumento em 4% os mesoporos em relação à argamassa de referência. No ensaio de absorção por capilaridade, as argamassas apresentaram taxas menores em relação à argamassa de referência, comprovando o efeito fíler da CLETA na matriz.
127

Modelo conceitual de seleção de tecnologias de tratamento de água para abastecimento de comunidades de pequeno porte / Conceptual selection model of technologies of water treatment for the supply of small communities

Lyda Patricia Sabogal Paz 28 September 2007 (has links)
Os investimentos no setor de água potável no Brasil, apesar de significativos, ainda não apresentam os resultados esperados na melhoria da saúde e da qualidade de vida da população, especialmente nas pequenas comunidades do país. A aplicação de recursos continuará limitada enquanto não forem fortalecidos os aspectos técnicos, econômicos, institucionais, ambientais, sociais e culturais que permitam a seleção de obras sanitárias eficientes e sustentáveis. Neste contexto, foi desenvolvido um modelo conceitual de seleção de tecnologias de tratamento de água constituído por 17 sub-níveis que progressivamente \"filtram\" as opções tecnológicas aplicáveis em comunidades brasileiras inferiores a 20.000 habitantes. Os aspectos envolvidos no modelo se relacionam: i) ao risco presente na fonte de abastecimento superficial; ii) à eficiência das tecnologias para eliminar ou reduzir o risco a valores de acordo à Portaria no 518 (2004); iii) ao tratamento, aproveitamento e disposição dos resíduos gerados e iv) aos custos dos sistemas com vazões de projeto de 10 a 40 L/s. As principais conclusões da pesquisa foram: i) a aplicabilidade do modelo está restrita à estações de tratamento de água - ETAs que cumprem todos seus requisitos de domínio, ii) os valores-limite das variáveis de risco podem conduzir o engenheiro a uma seleção preliminar das possíveis alternativas de tratamento; entretanto, somente a partir de estudos de tratabilidade da água e de testes em instalação piloto será possível definir a ETA mais conveniente, iii) as seleções das tecnologias para tratamento, aproveitamento e disposição do resíduo não devem ser avaliadas de forma independente às empregadas nas ETA; iv) Os custos calculados pelo modelo dificilmente podem ser comparados com sistemas já existentes; v) os resultados do modelo variam em função dos dados de entrada; assim, o usuário deve ter consciência da qualidade da informação fornecida para obter resultados satisfatórios. / Despite being significant the investments in the brazilian drinking water sector still have not presented the expected results regarding the improvement of both health and population\'s life quality, especially in the small communities of the country. The application of resources will continue limited while the technical, economical, institutional, environmental, social and cultural aspects that allow for the selection of efficient and maintainable sanitary works are not strengthened. In this context, a conceptual model to select technologies for water treatment has been developed. It consists of 17 sub-levels that progressively \"filter\" the applicable technological options in brazilian communities of under 20.000 inhabitants. The aspects involved are related to: i) the risk present in the source of superficial supply; ii) the efficiency of the technologies to lither eliminate or reduce the risk to the values according law no 518 (2004); iii) the treatment, use and disposition of the generated residues and iv) the costs of the systems with project flows from 10 L/s to 40L/s. The main conclusions of the research were: i) the applicability of the model is restricted to water treatment plants - WTPs that accomplish all their domain requirements, ii) the limit values of the risk variables can lead the engineer to a preliminary selection of the possible treatment alternatives; however, only from studies of water treatment and tests in pilot installations it will be possible to define the most convenient WTP, iii) the selections of the technologies for treatment, use and disposition of residues should not be appraised in an independent way of the ones employed in WTPs, iv) the costs calculated by the model can hardly be compared with systems already existent; v) the results of the model vary in function of the input data; therefore, the user should be aware of the quality of the information supplied to obtain satisfactory results.
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Évaluation de l'état de contamination des bassins versants par les résidus de médicaments : utilisation des biofilms épilithiques comme marqueur d'imprégnation du milieu / Study of contamination level of watersheds by pharmaceuticals : epilithic biofilms as impregnation marker

Laurent, Elodie 10 December 2013 (has links)
L'état des milieux aquatiques est un point essentiel de l'évaluation demandée par la Directive Cadre Européenne (DCE 2000/60/CE) visant à préserver ou à restaurer les masses d'eau superficielles et souterraines d'ici à 2015. A cet égard, les médicaments font désormais partis des contaminants organiques largement recherchés dans les eaux continentales de surface mais leur écodynamique sur tout un bassin versant est encore méconnue. Ce travail a ainsi apporté une évaluation de l'état de contamination de bassins versants par les médicaments à l'aide des biofilms épilithiques comme marqueur de l'imprégnation du milieu.La cartographie de l'imprégnation du bassin versant de la Vienne a permis de mettre en évidence une plus forte concentration en médicaments dans la partie amont du bassin que dans la partie aval (associée à la transition entre le socle granitique et les bassins sédimentaires). Les teneurs en médicaments mesurées dans les biofilms ont montré un facteur de concentration de 1000 par rapport aux teneurs rencontrées dans l'eau – traduisant ainsi un phénomène de bioaccumulation dans ce compartiment.L'hétérogénéité de l'habitat benthique (diversité des roches, différence d'exposition) influence le niveau d'imprégnation des biofilms sous certaines conditions d'exposition à un rejet.La majeure partie des biofilms situés en aval de l'ensemble des stations d'épuration est plus fortement contaminée. En revanche les mesures d'imprégnation effectuées sur le bassin de l'Arve n'ont montré aucun effet significatif de l'apport d'une station d'épuration recevant les effluents du Centre hospitalier Alpes Léman. / The European Water Framework Directive (DCE 2000/60/CE) aims to restore and protect aquatic ecosystems with the preservation of chemical and ecological status by 2015. In this sense, pharmaceuticals are part of organic contaminants currently investigated in surface waters but their fate along a watershed is still poorly known. This study has made an assessment of the contamination level of watersheds by pharmaceuticals using epilithic biofilms as a marker of the impregnation of the habitat.The impregnation mapping of the Vienne River watershed has highlighted a higher pharmaceutical concentration in the upper part of the river than in the lower part (associated with the transition from the granitic bedrock to the sedimentary basin). Pharmaceutical concentrations measured in the biofilms were 1000-fold higher than concentrations found in water – reflecting a phenomenon of bioaccumulation in this compartment.The habitat heterogeneity (rock diversity, exposure level) influences the impregnation degree of biofilms, depending on the exposure to point source pollution.Most biofilms located downstream from a wastewater treatment plant discharge were heavily contaminated with pharmaceuticals. On the other hand, the biofilms collected from the Arve River watershed have shown no significant effect of a wastewater treatment plant discharge receiving effluents from the hospital "Centre hospitalier Alpes Léman" on the impregnation of biofilms.
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Fosforsläpp och vigg i polerdamm vid Västra strandens avloppsreningsverk i Halmstad

Hansson, Ulf January 2017 (has links)
During the winters in recent years Laholmsbuktens VA's treatment plant in Halmstad has recorded unexcepted levels of phosphorus from the polishing pond. Only between 8 and 20 January 2016 samples indicates a realese of net 75 kg. In winter the pond temperature never goes below about 8oC, which attracts wintering waterfowl. In February 19, 2016 the largest number of birds in the inventory for this thesis was noted, 325 individuals, of which 208 were tufted ducks.  Even if the number of waterfowl at peak levels was to be about 1000 individuals, their combined contribution of phosphorus through droppings into the pond could not be more than 500 g per day. This study proposes that a significant factor is the foraging activity of tufted ducks, which are diving ducks. In search of food at daytime they disturb the sediment at the bottom of the pond, i.e bioturbation.  The higher proportion of particle-bound phosphorus in samples with high phosphorus content also fits well with this hypothesis. A scientific investigation in which the bottom of this part of the pond was stirred up mechanically gave similar proportions between phosphorus and water-soluble phosphorus.
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An investigation into the cyanobacteria and related cyanotoxins in the Vaalkop dam and Vaalkop Treatment Plant, Rustenburg

Bezuidenhout, Nelanie 24 July 2013 (has links)
M.Sc. (Environmental Management) / In South Africa, there are practically no freshwater lakes. Therefore, exploitable water supplies are confined to rivers, artificial lakes behind dams, and groundwater. The many demands for water, and the erratic flow of most South African rivers, have led to the creation of artificial lakes and dams, i.e. impoundments on all the major rivers, in order to stabilise flow and therefore guarantee annual water supply. Cyanobacterial bloom formation in freshwater sources, such as rivers, lakes, dams and reservoirs are known to occur throughout the world. In South Africa, the occurrence of cyanobacteria has also been recorded with the best known being the bloom of the hyper-eutrophic Hartbeespoort Dam. In South Africa specifically, cyanobacteria are mostly seasonally driven. Species that are known to cause bloom formation are Microcystis sp., Anabaena sp., Oscillatoria sp. and Cylindrospermopsis sp. These species are known to produce cyanotoxins that cause health problems in animals and humans, but also produce taste and odour problems in drinking water, if not treated effectively. In most cases where cyanobacteria blooms have been known to occur, it also enters source water for drinking water purification plants. Because source water containing cyanobacteria and the effect it has on the consumer, environment and animals, it is thus important to identify the dominant algae species. Cyanotoxin drinking water guidelines must be developed and implemented and a management plan for the Water Treatment Plant must be produced, to ensure that the risk of human exposure to the cyanotoxins are minimised. The present study focuses on the Vaalkop Dam from which raw water is abstracted and treated by the Magalies Water Vaalkop Water Treatment Plant (MWVWTP) to produce potable water. The source water abstracted from the Vaalkop Dam can contain high numbers of cyanobacteria as well as cyanotoxins that must be removed by the MWVWTP during potable water purification to ensure compliance to water quality standards. The overall objective of the study is to investigate the occurrence of cyanobacteria and cyanotoxins in the Vaalkop Dam at the point where the source water is abstracted for drinking water purification.

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