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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.
101

Diagnóstico dos resíduos gerados em estações de tratamento de água nas bacias dos rios Piracicaba, Capivari e Jundiaí - SP

Vilella, Alexandre Luis Almeida 20 July 2011 (has links)
Made available in DSpace on 2016-06-02T20:00:38Z (GMT). No. of bitstreams: 1 3860.pdf: 7904482 bytes, checksum: fcce0b9ff411b2bc48b7a967806bdb8c (MD5) Previous issue date: 2011-07-20 / The basins of Piracicaba, Capivari and Jundiaí has a territory of 15,304 square kilometers, about 5.2 million inhabitants, 7% of gross national product. However, the scarcity of water resources threatens all this prosperity. The uses of water have led to conflicts because of its multiple and diverse purposes, which require different quantities and qualities. It is against this background that becomes fundamental to understand the current situation of water supply and waste management from the treatment process. The mobilization of society, awareness of public officials and increase the availability of financial resources for the sanitation sector have provided the municipalities to increase their rates of water treatment, through the construction of new structures and technological innovations, however, has aroused another focus attention to the urgent need for the systemic management of waste from water treatment plants, especially the generation, treatment and disposal of sludge and its actual and potential environmental impacts. This research has made diagnosis of generation under the quantitative aspect of the sludge generated in the 89 water treatment plants operating in 58 cities, and identify some experiences about the management. Through various methodological tools, such as the use of questionnaires for data collection to obtain primary data, the paper presents and discusses information about the current generation of waste, existing experiences regarding the disposal and treatment, and the challenges issue requires to be addressed. The results pointed that 9013.20 tons of monthly dry solids are generated, with prominence the one that 70% of plants in operation don't possess any of measurement of the muds system. The realities, front to the service of the effective legislations, training lack and the managers systemic administration and operators on the theme as well as the need of the integration of the sectorial politics with the operation of the systems of water supply that are the great challenges to be overcome. / As bacias hidrográficas dos Rios Piracicaba, Capivari e Jundiaí possuem um território de 15.304 Km², cerca de 5,2 milhões de habitantes, 7% do Produto Interno Bruto Nacional. No entanto, a escassez dos recursos hídricos ameaça toda essa prosperidade. Os usos da água têm gerado conflitos em razão de sua multiplicidade e finalidades diversas, as quais demandam quantidades e qualidades diferentes. É diante desse panorama que se torna fundamental o conhecimento do cenário atual do abastecimento de água e a gestão dos resíduos oriundos do processo de tratamento. A mobilização da sociedade, a conscientização dos gestores públicos e o aumento da disponibilidade de recursos financeiros para o setor de saneamento têm proporcionado que os municípios aumentem os seus índices de tratamento de água, através da construção de novas estruturas e inovações tecnológicas, entretanto, tem despertado a atenção para outro foco, a premente necessidade da gestão sistêmica dos resíduos oriundos das estações de tratamento de água, com destaque a geração, tratamento e disposição dos lodos e seus potenciais e efetivos impactos ambientais. Este trabalho procurou diagnosticar a geração sob o aspecto quantitativo dos lodos gerados em 89 ETAs em operação nos 58 municípios paulistas integrantes da UGRHI n.° 5, além de identificar algumas experiências quanto ao gerenciamento. Através de diversos instrumentos metodológicos, como a utilização de questionários de coleta de dados para obtenção de dados primários, a adoção de métodos teóricos, visitas técnicas, o trabalho apresenta e discute as informações acerca da geração atual desses resíduos, as experiências existentes quanto à destinação final e tratamento, além dos desafios que a temática exige a serem enfrentados. Os resultados apontaram que são gerados 9013,20 toneladas de sólidos secos mensais, com destaque a que 70% das ETAs em operação não possuem sistema algum de medição dos lodos. As realidades, frente ao atendimento das legislações vigentes, carência de capacitação e gestão sistêmica dos gestores e operadores sobre a temática bem como a necessidade da integração das políticas setoriais com a operação dos sistemas de abastecimento de água que se demonstraram como grandes os desafios a serem superados.
102

ObservaÃÃes Sobre o FitoplÃncton de Lagoas de EstabilizaÃÃo e AvaliaÃÃo de RemoÃÃo Algal Via FlotaÃÃo com Ar Dissolvido / Observations on phytoplankton of Stabilization Ponds and Evaluation of Algal Removal Via Dissolved Air Flotation

Expedito RÃmulo Amado de Oliveira 08 May 2013 (has links)
nÃo hà / A composiÃÃo, variaÃÃo semanal, e avaliaÃÃo de remoÃÃo de biomassa fitoplanctÃnica por FlotaÃÃo com Ar Dissolvido de um sistema de lagoas de estabilizaÃÃo da EstaÃÃo de Tratamento de Esgoto de Aquiraz â CE foi estudada durante o perÃodo de maio a dezembro de 2011. Analisando-se dados de eficiÃncia de remoÃÃo de SÃlidos, DQO, DBO, Turbidez, Coliformes e densidade de organismos. Qualitativamente o fitoplÃncton apresentou-se composto por 36 tÃxons especÃficos, distribuÃdos por 14 clorofÃceas, 11 euglenofÃceas, 7 cianobactÃrias, 2 bacilariofÃceas, uma criptofÃcea e apenas uma clamidofÃcea. Apesar do nÃmero de espÃcies de algas verdes, o destaque em densidadade e frequÃncia foi de Planktotrhix agardhii, espÃcie conhecida como produtora de toxinas, dominando durante todo o perÃodo estudado. Esta espÃcie foi suplantada em pouquÃssimas semanas por algas verdes cocÃides. Ocorreu decrÃscimo do nÃmero de classes entre as lagoas ao longo da pesquisa com reduÃÃo e piora da riqueza de espÃcies entre as lagoas, culminando com a concentraÃÃo de mais de 90% da composiÃÃo dos organismos pertencentes a uma Ãnica espÃcie de cianobactÃria. Cyanophyceae foram encontradas com mÃdias de 7,9x105 a 1,6 x 106 org./mL. Os resultados sÃo preocupantes no que tange à potencialidade tÃxica da espÃcie dominante e que à lanÃada no Rio Pacoti alÃm de as lagoas se comportarem como estoque de hormogÃnios e replicaÃÃo desses organismos para o ambiente. Nos ensaios de remoÃÃo, o efluente da Lagoa de MaturaÃÃo B possuÃa 5,7 x 104 ind/mL, 132 NTU de turbidez, 4,8x103 NMP de E. coli. Os testes de flotaÃÃo com ar dissolvido mostram-se promissores. ApÃs flotaÃÃo, caÃram para 291,4 org/L, 2,7 NTU, 102NMP de E. Coli/100mL. A menor eficiÃncia foi de DBO, alcanÃando mÃdias de 73%. A DQO foi removida em 80%. A flotaÃÃo teve que ser auxiliada por coagulantes. Foi removido 98% dos organismos fitoplanctÃnicos, 98,8% de coliformes e 98% da turbidez. E. coli foi reduzida em duas unidades logarÃtmicas, resultando em <600 NMP/100mL. A baixa concentraÃÃo bacteriana permite indicar, apÃs desinfecÃÃo simples, o reÃso para fins de irrigaÃÃo urbana, lavagem de automÃveis e outros usos de contato humano restrito. / The composition, weekly change, and evaluation of removal of phytoplankton biomass by Dissolved Air Flotation with a system of stabilization ponds Station Wastewater Treatment Aquiraz - EC was studied during the period from May to December 2011. Analyzing data removal efficiency of solids, COD, BOD, Turbidity, Coliform and density of organisms. Qualitatively the phytoplankton is composed of 36 specific taxa spread over 14 green algae, 11 euglenoids, 7 cyanobacteria, 2 bacilariofÃceas, 1 criptofÃcea and only one clamidofÃcea. Although the number of species of green algae, the highlight densidadade and frequency was Planktotrhix agardhii, species known as producing toxins, dominating throughout the study period. This species has been supplanted in a very few weeks a coccoid green algae. Decrease occurred in the number of classes among the ponds along the survey reduction and worsening of species richness among lakes, culminating with the concentration of more than 90% of the composition of organisms belonging to a single species of cyanobacteria. Cyanophyceae were found with averages of 7.9 x105 to 1.6 x 106 org./mL. The results are worrying regarding the toxic potential of the dominant species and is thrown into the River Pacoti plus ponds behave like stock hormogon and replication of these organisms to the environment. In tests of removal, effluent Maturation Pond had 5.7 x 104 ind / mL, 132 NTU turbidity, 4,8 x103 NMP E. coli. The flotation tests with dissolved air show to be promising. After flotation, fell to 291,4 org/L, 2.7 NTU, 102 NMP E. Coli/100mL. The lowest efficiency of BOD, reaching averages of 73%. The COD was removed at 80%. Flotation had to be helped by coagulants. Was removed 98% of the phytoplanktonic organisms, 98.8% of fecal and 98% turbidity. E. coli was reduced by two logarithmic units, resulting in <600 NMP/100mL. The low bacterial concentration allows state after simple disinfection, reuse for irrigation, urban car washing and other uses of human contact restricted.
103

Segurança e higiene do trabalho em estações de tratamento de agua / Work and hygiene safety in water treatment plants

Causo Neto, João Pedro, 1952- 23 August 2006 (has links)
Orientador: Bruno Coraucci Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T18:42:30Z (GMT). No. of bitstreams: 1 CausoNeto_JoaoPedro_M.pdf: 2741267 bytes, checksum: 87cf7d40717c076cc3bf742697e76d87 (MD5) Previous issue date: 2006 / Resumo: Em locais com atividades humanas, tais como nas Estações de Tratamento de Água (ETA), há muitos fatores causadores de acidentes: uso de ferramentas diversas, máquinas ruidosas e sem proteções em partes móveis, substâncias químicas, pisos escorregadios ou irregulares, elementos energizados desprotegidos e ingresso em áreas com oxigênio insuficiente. Estes fatores, se previamente constatados, podem ser controlados, evitando danos à integridade física dos profissionais. Buscou-se, neste estudo, a identificação dos principais riscos no trabalho em ETAs e, através de parâmetros macro, o cumprimento da legislação de saúde e segurança nesta atividade. A metodologia consistiu na aplicação e análise de questionário específico, envolvendo técnicos de 45 empresas operadoras de ETAs no Estado de São Paulo, e em visitas técnicas a nove estações de tratamento. Concluiu-se que grande parte dos acidentes decorre do não atendimento, de forma plena, das obrigações e programas contidos nas normas regulamentadoras existentes na legislação brasileira, e pela necessidade de melhorar o sistema de registro dos acidentes / Abstract: In places with human activities, such as Water Treatment Plants (WTP), there are many factors which can cause accidents: the use of various tools, noisy machinery without protection on mobile parts, chemical substances, slippery or irregular floors, unprotected electric devices, and entrance in unenough oxygenated places. When previously identified, these factors can be manipulated to avoid damages to the physical integrity of professionals. In this study, the identification of the main factors of risk were looked for, while working at WTP, and the compliance with health and safety regulation through the macro parameters. The methodology consisted of an application and analysis of a specific questionnaire, involving technicians of 45 enterprising operators of WTP in the São Paulo State, and in technical visits to nine treatment stations. It was concluded that a major part of accidents happened for lack of attendance, in a overall manner, upon obligations and programs included in the existing regulation norms in the Brazilian legislation, and by the necessity of bettering the system of accidents register / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
104

The development and harmonisation of risk assessment procedures to evaluate the environmental impact of toxic substances

Robinson, Nikki Lee January 2001 (has links)
The environmental risk assessment of substances is introduced and the various controls used to protect the environment are outlined. The European notification system and the risk assessments required as part of the system are detailed. Through an examination of the existing European Union System for the Evaluation of Substances tool and sensitivity analyses based on variability in the measurement of physico-chemical properties for a substance, a spreadsheet model was developed to allow multiple risk assessments for the same substance to be calculated simultaneously. The development and testing of the NECXES spreadsheet tool are documented in detail. Data for the capacity and dilution factor at Sewage Treatment Plants (STPs) in England and Wales were collated and statistically analysed and compared to European default values used for generic risk assessments. The default capacity value for STPs (10,000 population equivalents) was protective of 70% of the STPs sampled. The remaining 30% however, a small number of large works, contributed 94% of the total effluent discharged from STPs in England and Wales. The STP data were used with the NEXCES tool to perform and compare probabilistic risk assessments to those calculated using deterministic methods for a number of test substances. The probabilistic calculations produced a lower median exposure concentration for water than the generic assessment for all of the test substances. Regression analysis allowed the probability of adverse effects to be quantified for the various deterministic risk values. The NEXCES tool was also used to develop a rapid assessment tool for new substances in the form of contour plots, which can be used to assess the risk of substances using minimal data. The main conclusions and contributions to the academic and industrial fields, as well as the field of environmental technology are presented. Areas where there are opportunities for further research are also outlined.
105

Étude de l'impact des effluents urbains sur la qualité des eaux de la Garonne estuarienne : application aux composés pharmaceutiques et aux filtres UV / Occurrence and fate of pharmaceuticals and UV filters in urban effluents and in the estuarian Garonne River

Aminot, Yann 06 December 2013 (has links)
Dans le contexte de la contamination quasi-généralisée des eaux de surface par les médicaments, les travaux de cette thèse portent sur l’étude des niveaux de concentration et du devenir de ces micropolluants organiques dans la Garonne estuarienne, recevant les effluents traités de l’agglomération bordelaise. Après le développement et la validation des outils analytiques associés à la détection multi-résidus dans les matrices eau et sédiment, la composition et la variabilité des effluents urbains bordelais ont été caractérisées, avant et après traitement en station d’épuration. La contamination globale des compartiments eau, matières en suspension et sédiment a ensuite été évaluée sur une rivière périurbaine de l’agglomération. Par ailleurs, le suivi réalisé en Gironde montre l’importance relative des apports amont et urbains et met en évidence la dégradation in-situ de certains médicaments, par ailleurs confirmée par une expérience d’incubation d’eau estuarienne réalisée in-vitro. / Ubiquitous presence of pharmaceuticals in the environment is of great concern. In this Ph.D. work, occurrence and fate of these organic contaminants were studied in the estuarine Garonne River, receiving treated effluents of the Bordeaux urban area (France). After developing and validating the analytical methods for multi-residue detection of 53 pharmaceuticals in water and sediment, composition and variability of the Bordeaux wastewater treatment plant influents and effluents were characterized. Presence of analytes in river water, suspended solids and sediments was then investigated on a periurban river located in the suburbs of Bordeaux. Besides, a long-term monitoring of estuarine Garonne River revealed the relative importance of local and upstream inputs and clearly showed a seasonal in-situ degradation of certain pharmaceuticals. This degradation was further confirmed and examined through batch experiments simulating the mixing conditions of wastewater and estuarine river water, highlighting the importance of suspended solid concentration in biodegradation rates.
106

ANALYSIS, OCCURRENCE, FATE AND TREATABILITY OF N-NITROSAMINES AND THEIR FORMATION POTENTIAL IN WASTEWATER TREATMENT PLANTS / 下水処理場におけるN-ニトロソアミン類と生成能の分析、存在実態、挙動および処理性能に関する研究

Yoon, Suchul 26 September 2011 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第16387号 / 工博第3468号 / 新制||工||1524(附属図書館) / 29018 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 清水 芳久, 教授 伊藤 禎彦 / 学位規則第4条第1項該当
107

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.
108

Condicionamento químico de lodo de estação de tratamento de água com monitoramento através de potencial redox / Chemical conditioning of sludge from a water treatment plant with monitoring through redox potential

Haak, Wando 18 August 2018 (has links)
Orientador: Ricardo de Lima Isaac / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T11:03:55Z (GMT). No. of bitstreams: 1 Haak_Wando_M.pdf: 4830827 bytes, checksum: 311caf27f5b5da6d03f6312ef08d15bc (MD5) Previous issue date: 2011 / Resumo: Estações de tratamento de água (ETA) geram resíduos durante o processo de potabilização da água bruta. Esse resíduo onera as companhias de saneamento, no que tange o tratamento e disposição final. O tratamento do lodo é constituído de processos de separação sólido-líquido, cuja eficiência - quanto à maximização do teor de sólidos da torta (lodo desaguado) e melhor qualidade da água recuperada no processo - é dependente do adequado condicionamento químico, em geral obtido pela ação de polímeros. A super- dosagem ou a sub-dosagem desse produto ocasiona perda de qualidade, tanto da torta, quanto da água eliminada. Este trabalho tem como objetivo verificar através de estudo de bancada, a viabilidade técnica e econômica do condicionamento químico na adequação de processo de tratamento de lodo de ETA, visando melhor desempenho na fase de desaguamento, tendo em vista a disposição final dos resíduos gerados durante o tratamento. Foram relacionadas medidas de potencial redox com controle de dosagem e consumo de polímero catiônico de alto e muito alto peso molecular, de baixa, média e alta densidade de carga e polímero aniônico de alto peso molecular, com baixa e média densidade de carga, com e sem oxidação química com cloro e permanganato de potássio. Na investigação experimental os resultados referentes ao tempo de filtração, indicaram os polímeros catiônicos de alto peso molecular, de baixa e média e alta carga como sendo mais eficientes. Para valores de potencial redox entre -57mV e 75mV, os polímeros catiônicos, em sua maioria, apresentaram consumos de 6,0 a 10,0 (kg/tms), em lodo não oxidado. A oxidação do lodo com permanganato de potássio ou cloro para valores entre -11mV e +11mV foi significativa, com redução da dosagem de polímeros catiônicos para valores de 4,0 a 7,0 (kg/tms), proporcionando economia de 30%. Considerando-se as correlações encontradas, tendo em mãos, sondas confiáveis de pH e potencial redox, é possível automatizar um determinado sistema de dosagem para oxidação do lodo / Abstract: Water treatment plants (WTP) generate waste during the process of potabilization of raw water. This residue burdens the sanitation companies, with regard to treatment and final disposal. The sludge treatment process consists of solid-liquid separation, whose efficiency - as to maximize the solids cake (dewatered sludge) and better quality of the reclaimed water in the process - is dependent on proper chemical conditioning, usually obtained by action of polymers. Over dosage or under dosage of those products causes loss of quality of both, cake and eliminated water. The aim of this work is to verify the technical and economical feasibility of the chemical conditioning at the fitting of sludge treatment process at a WTP, through work bench study, aiming at better performance during the dewatering, looking at the treatment final discharge of residues. Measures of redox-controlled dispensing were related to consumption of cationic polymer of high and very high molecular weight, of low, medium and high charge density and anionic polymer of high molecular weight, of low and medium charge density, with and without chemical oxidation with chlorine and potassium permanganate. At the primary investigation of percolating time, the cationic polymers of high molecular weight with low, medium and high charge, proved to be more efficient. For potential redox values between -57mV and 75mV, most of the cationic polymers consumed from 6.0 to 10.0 (kg/tms), in non-oxidized sludge. There was a significant oxidation of sludge with potassium permanganate or chlorine for values between -11 and +11mV, reducing the dosage of cationic polymers to values from 4.0 to 7.0 (kg/tms), providing a 30% economy. Taking into account the correlations found, using reliable pH and redox potential probes, it is possible to automate a system of dosage for the sludge oxidation / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
109

Ekotoxikologické posouzení bodových zdrojů znečištění v ekosystému / Ecotoxicological Assessment of Point Pollution in the Ecosystem

Doležalová, Šárka January 2018 (has links)
The main subject of this dissertation is the ecotoxicological evaluation of significant point sources of pollution. These include wildfires and wide fires of factories and also industrial and urban wastewater treatment plants. The local application of pyrolytic product obtained from sewage sludge as the point source of pollution was also included in the thesis. Tests in aquatic and contact arrangement with using both water and soil organisms for ecotoxicity evaluation of selected matrices were chosen. Crustaceans Thamnocephalus platyurus, Daphnia magna Straus and sea bacteria Vibrio fischeri were selected as representative organisms of water animals. Duckweed Lemna minor was chosen as water plant. Further collembola Folsomia candida and earthworm Eisenia fetida were chosen as representatives of soil animals. Finally onion Allium cepa L. and mustard Sinapis alba are representatives of terrestrial plants. Submitted thesis deals about analytes of interest, their properties and ways of distribution to the environments. The output of the thesis is a comprehensive assessment of the effects of selected point sources of pollution on aquatic and terrestrial ecosystems organisms and ecotoxicological risks assessment. The fire extinguishing agents have been proven to be the most stressful substances for all selecteded organisms.
110

Intenzifikace čistírny odpadních vod v obci Krumsín / Intensification of the wastewater treatment plant in the village Krumsín

Krejsová, Věra January 2014 (has links)
The task of this master thesis was assessment of the possibility of intensification of biological ponds, which are used for wastewater treatment, and subsequent application of selected systems to the existing wastewater treatment plant in the village Krumsin in the district Prostejov, including economic assessment. In the first part of the master thesis, I worked up the available options for the intensification of biological ponds. In the practical part of the thesis it was prepared a report of the current state of the wastewater treatment plant that serving as a basis for the design of intensification, which is also processed in the practical part. For the proposed variants of intensification was also processed economic assessment.

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