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Criterios para reuso de agua em industrias : aproveitamento do efluente da estação de tratamento de esgoto do Piçarrão, Campinas - SP / The criterion for water reuse in industry : utilization of effluent of the station of sewer treatment of Piçarrão, Campinas - SPViaro, Vivien Luciane 27 February 2007 (has links)
Orientador: Ricardo de Lima Isaac / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T18:44:13Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: O município de Campinas, inserido em uma das regiões mais desenvolvidas do estado de São Paulo, enfrenta crises pelo uso da água - um dos notórios conflitos com a região metropolitana de São Paulo. Diante da escassez quantitativa e qualitativa da água para atender aos múltiplos usos, pressões legais e institucionais têm exigido que os municípios aí localizados tratem os esgotos municipais, com intuito de preservar e recuperar a qualidade da água dos principais mananciais superficiais utilizados para abastecimento público. Nesse contexto, o reúso mostrase como uma alternativa para atender as demandas menos restritivas quanto à qualidade da água, permitindo que o efluente tratado proveniente de novas estações e atuais de tratamento de esgoto (ETE) possa ser aplicado para fins não-potáveis. O escopo deste trabalho avaliou a viabilidade do reúso do efluente tratado da ETE Piçarrão. De acordo com dados disponibilizados pela estação, foi possível avaliar as características qualitativas do efluente tratado, delimitando as possíveis aplicações, de acordo com normas e padrões internacionais. Com o auxilio de um sistema de informações geográficas (SIG) e dos métodos multicriteriais: Compromise Programming (CP) e o Cooperative Game Theory (CGT) foi definida uma hierarquia entre as alternativas localizadas na bacia de esgotamento da ETE, baseada nos aspectos ambientais, técnicos, econômicos e legais. Trata-se de um suporte à tomada de decisão para o gerenciamento dos recursos hídricos no espaço urbano, aplicável às outras estações de tratamento de esgoto existentes ou previstas no município de Campinas, São Paulo / Abstract: The city of Campinas, which is inserted in one of the most developed areas of the state of São Paulo, faces crises due to use of the water - One of the well-known conflicts of the metropolitan area of São Paulo. Due to the quantitative and qualitative shortage of water assisting to multiple uses, legal and institutional pressures have been demanding that the municipal districts located there treat the city sewers, intending to preserve and to recover the quality of the main superficial spring waters used for public provisioning. In that context, the reuse is shown as an alternative to assist the less restrictive demands related to the quality of the water, allowing the treated effluent originated from new and current stations of sewer treatment (ETE) be applied for no-drinkable ends. The mark of this work evaluated the viability of the reuse of ETE Piçarrão's treated effluent. According to data provided by the station, it was possible to evaluate the qualitative characteristics of the treated efluente, delimiting the possible applications, according to international norms and patterns. With the aid of a system of geographical information (SIG) and of the multi-criteria methods: Compromise Programming (CP) and Cooperative Game Theory (CGT) was classified among the options located in the basin of exhaustion of ETE based on the environmental, technical, economical and legal aspects. This is about a support to thedecision-making for the administration of water resources in the urban space applicable to the other stations of sewer treatment existent or predictable in the city of Campinas, São Paulo / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil
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Tratamento de esgotos pelo sistema combinado filtro anaerobio e filtros de areia / Water treatment by the combination of an upflow anaerobic filter and sand filterTonetti, Adriano Luiz, 1973- 25 February 2008 (has links)
Orientadores: Bruno Coraucci Filho, Roberto Feijo de Figueiredo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T03:44:49Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: Nesta pesquisa estudou-se um sistema para o tratamento de esgotos de pequenas comunidades composto pela combinação de filtro anaeróbio com filtro de areia e reator de desnitrificação. Para isso foi avaliada a partida e a operação de três filtros anaeróbios com recheio de bambu operados com tempo de detenção hidráulica nominal de 9 horas, sendo o efluente gerado disposto sobre os leitos de quatro filtros de areia em distintas taxas de aplicações. No primeiro filtro de areia aplicaram-se 50 Lm-2 uma vez por dia. No segundo, terceiro e quarto filtro, esta mesma carga foi disposta em dois, três e quatro horários, espaçadas entre as 9 horas e às 16 horas, correspondendo às taxas de 100, 150 e 200 Lm2dia. Cada filtro de areia era seguido por um reator de desnitrificação em que se buscou um meio propício à remoção do nitrogênio, objetivando adequar o efluente ao lançamento em um corpo hídrico e como água de reúso. O sistema foi avaliado quanto a parâmetros físicos, químicos e biológicos. Como resultado, o efluente atendeu a legislação de Minas Gerais e São Paulo quanto a DQO e DBO e, após a correção do pH e adição de efluente anaeróbio como fonte de carbono, obteve-se uma remoção de 43,5% de N-total no reator em que se aplicou 50 Lm-2dia-1, passando a ter um grau moderado para a prática agrícola.
Palavras-chave: esgoto, filtro de areia, tratamento, desnitrificação, reúso / Abstract: The main objective of this research was to study an onsite system to treat the wastewater from small villages. The system was constituted by the combination of an upflow anaerobic filter followed by a sand filter and a denitrification reactor. The start up and the operation of three upflow anaerobic filters filled with bamboo rings were evaluated. These filters were operated with hydraulic detention time of 9 hours. The produced effluent was disposed over four sand filters in different frequencies of application. On the first sand filter, 50 Lm-2 were applied once a day. On the second, the third and the fourth filters, the same load was disposed in twice, three and four times a day, distributed between 9 am and 4 pm. Each sand filter was followed by a denitrification reactor aiming at the removal of total nitrogen, thus making appropriate the effluent for discharge or water reuse. Weekly, the system was evaluated by analyses including physical, chemical and biological parameters. As a result, the effluent was suitable for the COD and BOD legislation and, after the pH correction and the addition of external carbon source, a removal of 43,5% from total-N was reached in the reactor which received a load of 50 Lm-2dia-1, consequently the effluent was ready to be used within a slight to moderate degree of restriction.
Keywords: wastewater, sand filter, treatment, denitrification, reuse / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil
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AvaliaÃÃo do Atual Potencial de ReÃso de Ãgua no Estado do Cearà e Propostas Para um Sistema de GestÃoClÃudia ElizÃngela Tolentino Caixeta 25 January 2010 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Este trabalho teve como objetivo avaliar o potencial de reÃso de Ãguas no Estado do Cearà como forma de contribuir para o efetivo gerenciamento dos recursos hÃdricos e para a conservaÃÃo ambiental do Estado. O trabalho foi desenvolvido observando as seguintes etapas: (1) levantamento bibliogrÃfico; (2) caracterizaÃÃo do Estado do Cearà (Ãrea de estudo); (3) definiÃÃo das alternativas e critÃrios de reÃso; (4) levantamento das ETEs com respectivas vazÃes e as caracterÃsticas do sistema de tratamento para seleÃÃo daquelas cujos efluentes podem ser utilizados; (5) proposiÃÃo do(s) tipo(s) de reÃso para as ETEs selecionadas; (6) estudo de viabilidade econÃmica financeira para o reÃso industrial; (7) proposiÃÃo de condiÃÃes e diretrizes para o fortalecimento do reÃso no Estado; (8) apresentar e discutir os resultados; (9) avaliar o trabalho desenvolvido. O trabalho tem como resultados: (1) O reÃso industrial mostrou-se viÃvel para ser implantado no Distrito Industrial (DI) de MaracanaÃ, sendo que o efluente do tipo PadrÃo 2 (efluente da lagoa de estabilizaÃÃo, tanque de mistura para correÃÃo do pH, floculador, decantor tanque de recarbonataÃÃo e efluente final) foi o que apresentou melhor viabilidade econÃmico financeira. (2) Pesquisa realizada junto Ãs empresas do DI de MaracanÃu evidenciou grande receptividade por parte dos usuÃrios potenciais, desde que sejam garantidos qualidade, quantidade e preÃo competitivo com a atual fonte de abastecimento.(3) Dos 12 sistemas avaliados, a ETE Tupamrim foi a que apresentou condiÃÃes mais adequadas para a prÃtica do reÃso urbano nÃo potÃvel â rega de Ãreas verdes de Fortaleza. (4) Os sistemas de lagoas de estabilizaÃÃo em operaÃÃo na RMF e interior do Estado podem disponibilizar uma vazÃo de cerca de 1.872,0 L/s, e tais volumes poderÃo beneficiar cerca de 3.279,66 hectares, considerando uma demanda para irrigaÃÃo igual a 18.000 m3/ha.ano; ou suprir, em mÃdia, uma Ãrea de cultivo de peixes de 1.497.600 m2 (149,7 ha). Com base nos resultados pode-se concluir: (1) A implementaÃÃo de reÃso de Ãgua no Cearà à uma alternativa importante a ser considerada no Plano Estadual de Recursos HÃdricos, pois poderÃ: contribuir efetivamente na preservaÃÃo dos recursos hÃdricos; aumentar a oferta de Ãgua para os setores agrÃcola, piscÃcola e industrial no Estado, por meio da disponibilizaÃÃo da Ãgua recuperada aos usos que possam prescindir de potabilidade; e disponibilizar um volume maior de Ãgua de boa qualidade aos usos nobres, conforme preconiza a Agenda 21. (2) Dentre as modalidades de reÃso estudadas para o Estado, todas se mostraram viÃveis, sendo o reÃso industrial o que vai necessitar de um maior investimento. Jà os reÃso agrÃcola e em piscicultura sÃo os mais fÃceis de serem implementados, necessitando apenas de uma determinaÃÃo do Governo do Estado para que seja firmada uma parceria entre Cagece e SDA e, dessa forma, viabilizar a implantaÃÃo dos projetos. (3) O reÃso de Ãguas residuÃrias no Estado do Cearà à uma alternativa viÃvel, desde que haja uma regulamentaÃÃo para minimizar os riscos epidemiolÃgicos que podem advir da prÃtica sem a adoÃÃo de barreiras mÃltiplas para garantir a proteÃÃo da saÃde populacional. à incontestÃvel a necessidade do estabelecimento de diretrizes que permitam que a prÃtica do reÃso se torne segura e difundida, contribuindo assim para a minimizaÃÃo do problema de escassez de Ãgua no Estado. / The main objective of this work was evaluate the potential for water reuse in the state of Ceara as a contribution to the effective management of water resources and the conservation of the state. It consisted of the following stages: (1) literature, (2) A bibliographical survey; (2) description of the Ceara State (area under study); (3) definition of alternatives and criteria for reuse, (4) survey of treatment plants with respective flow rates and characteristics of treatment system for selection of those whose effluent can be used, (5) proposition (s) type (s) to reuse the selected treatment plants, (6) economic feasibility study for the financial reuse industrial (7) conditions of proposition and guidelines for the strengthening of reuse in the State, (8) present and discuss the results and (9) assessing the work undertaken. As results of the study we can mention: (1) The industrial reuse was feasible to be deployed in DI MaracanaÃ, and the effluent standard type 2 (effluent from the stabilization pond, mixing tank for pH correction, flocculant, decantor, carbonation tank and final effluent) showed the best economic and financial viability. (2) Research conducted with companies in the DI Maracanaà showed great responsiveness on the part of potential users, since it is guaranteed quality, quantity and price competitive with current power supply. (3) Of the 12 systems evaluated the Tupamirim WTPT presented the best conditions for the practice of non-potable urban reuse - irrigation of green areas in Fortaleza (4) The system of stabilization ponds in operation in the RMF and the State can provide a flow of about 1872.0 L / s, and these volumes will benefit approximately 3279.66 hectares, whereas the demand for irrigation equal to18,000 m3/ha.ano, or supply, on average, a growing area of 1,497,600 m2 fish (149.7 ha). The main conclusions of this work are: (1) The implementation of water reuse in Cearà is an important alternative to be considered in the State Plan for Water Resources, as it may: contribute effectively in the conservation of water resources, increase the supply of water for agricultural, fish and industry in the state, through the provision of reclaimed water for uses that can dispense the drinking, and provide a greater volume of water of good quality to end uses, as recommended by Agenda 21.(2) Among the types of reuse study for the state, all proved viable. As the industrial reuse which will require a larger investment. Since the re-use agricultural and fish are the easiest to implement, requiring only a determination of the State Government so that it signed a partnership betweean Cagece and SDA thus enable the implementation of projects.(3) The reuse of wastewater in the state of Ceara is a viable alternative, but necessary regulations to mitigate the pest risk that may arise from the practice without the adoption of multiple barriers to ensure protection of population health. Is no denying the need to establish guidelines that allow the practice of reuse to become secure, ubiquitous, thus helping to minimize the problem of water scarcity in the state.
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Análise ambiental, energética e econômica de arranjo processual para reúso de água em refinaria de petróleo. / Environmental, energetic and economic analysis of a process design for water reuse in petroleum refinery.Victor Sette Gripp 18 December 2013 (has links)
Foi construído um modelo representativo do ciclo de vida da água em uma refinaria de petróleo, contemplando todos os usos a que esta se presta. Nesse contexto foram avaliados do ponto de vista ambiental, energético e econômico cenários em que etapas adicionais eram incorporadas ao tratamento de efluentes de forma a viabilizar o reúso de água e o fechamento do circuito na própria refinaria, reduzindo assim a necessidade de captação e, consequentemente, de tratamento da água bruta captada pela refinaria. O Cenário I corresponde ao cenário-base, sem implantação de nenhuma ação voltada ao reúso. No Cenário II, é incorporada a etapa adicional chamada Tratamento Fase 1, constituída por um processo de Clarificação seguido de uma Eletrodiálise Reversa (EDR) que permite o reúso de 255,7 m3/h dos 350 m3/h lançados inicialmente ao corpo hídrico no Cenário I. No Cenário III, é incorporada ao arranjo do Cenário II uma etapa de Cristalização Evaporativa para tratar o concentrado salino da EDR, recuperando, assim, mais 55,4 m3/h dos 350 m3/h lançados inicialmente, utilizando, para isso, vapor residual inicialmente não aproveitado pela refinaria. A análise ambiental foi desenvolvida por Avaliação do Ciclo de Vida (ACV) e constatou um desempenho muito semelhante dos três cenários. Apesar disso, a análise em perfil aberto, de impactos de midpoint, evidenciou ganhos ambientais significativos associados ao fechamento de circuito de água e, embora com vantagens muito discretas, o Cenário III apresentou um desempenho superior ao do Cenário II em todas as categorias e, na grande maioria delas, também superior ao desempenho do Cenário I. A análise de indicador único, em endpoint, destacou o impacto em Mudança Climática, relativo principalmente à queima de gás natural na caldeira para a geração de vapor, como o principal impacto ambiental associado ao ciclo de vida da água na refinaria, responsável por mais de 90% do valor correspondente ao resultado do indicador único. A análise energética foi desenvolvida utilizando-se o indicador de Demanda Cumulativa de Energia (CED) e resultou em um desempenho superior do Cenário I, ainda que com pequenas diferenças em relação aos Cenários II e III. O pior desempenho foi o do Cenário II. Comparando-se a contribuição relativa dos diferentes tipos de energia, destaca-se a energia de origem hidrelétrica, responsável por cerca de 80% do indicador único de CED em todos os três cenários. A análise econômica foi realizada por meio de indicadores tradicionalmente utilizados para a análise de viabilidade de projetos Taxa Interna de Retorno (TIR) e Valor Presente Líquido (VPL) , considerando, como referência, as regras de cobrança pelo uso da água vigentes na bacia do rio Paraíba do Sul. Com os preços cobrados atualmente pelo uso da água desta bacia, a implantação de ambos os cenários de reúso (II e III) não se viabiliza economicamente. Para que isso ocorra, o valor cobrado pelo uso da água teria que ser da ordem de 50 a 80 vezes maior do que o que é cobrado atualmente. Dentre os cenários de reúso, o Cenário II apresentou desempenho econômico superior ao do Cenário III. / It was built a representative model of the water life cycle within a petroleum refinery, considering all the uses in which it is applied. In this context, under environmental, energetic and economic perspective, different scenarios were analyzed, where further treatment stages were added to the wastewater treatment process so that recycled water could be provided back to the refining process, reducing, therefore, the need for freshwater intake and pretreatment by the refinery. Scenario I is the base scenario, without implementation of any water reuse aimed action. In Scenario II, it is incorporated the additional stage called Phase 1 Treatment, which consists of a Clarification process followed by an Electrodialysis Reversal (EDR).This enables the recycling of 255.7 m3/h from the 350 m3/h previously discharged to the water body in Scenario I. In Scenario III, it is incorporated to the Scenario II setting an Evaporative Crystallization process for treating the concentrated brine resulting from the EDR process. This enables the recovery of more 55.4 m3/h from the 350 m3/h initially released, using, for that, the energy from residual steam previously not used by the refinery. The environmental analysis was developed through Life Cycle Assessment (LCA) and found very similar performances for all three scenarios. Despite that, the open profile analysis, of midpoint impacts, showed significant environmental gains from the closure of the water circuit and, though with very small advantages, Scenario III showed a better performance than Scenario II in all impact categories and, in most of them, also better than Scenario I performance. The single score analysis, considering endpoint impact categories, highlighted Climate Change, specially related to the natural gas burning in the boiler for steam generation, as the main impact category associated to the water life cycle within the refinery, being responsible for more than 90% of all the value of the single score indicator. The energetic analysis was developed using the Cumulative Energy Demand (CED) indicator and resulted in a better performance of Scenario I, even if with just small differences from Scenarios II and III. The worst performance was from Scenario II. Comparing the relative contribution of the different types of energy, the hydroelectricity was the most important one, being responsible for around 80% of the CED single score in all three scenarios. The economic analysis was developed through traditional indicators used for assessing projects viability Internal Return Rate (IRR) and Net Present Value (NPV), considering, as reference, the rules of charging for water use valid nowadays at the Paraíba do Sul river basin. With the prices charged nowadays for the water use from this basin, the implementation of both reuse scenarios is not economic viable. In order to make it viable, the charged value would have to be around 50 to 80 times higher than it is today. Among the reuse scenarios, Scenario II had a better economic performance than Scenario III.
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Estudo do comportamento do processo de ozonização como pós-tratamento de efluentes de sistema de tratamento anaeróbio de águas residuárias domiciliares / Experimental study of the performance of the ozonization after anaerobic treatmentHerlane dos Santos Costa 21 February 2003 (has links)
Nessa pesquisa foi realizado um estudo experimental da potencialidade do emprego da ozonização após tratamento anaeróbio de efluentes, no que se refere a dosagem, tempo de contato, alcalinidade, aplicação conjunta com peróxido de hidrogênio, quantidade de ozônio consumida e oxidação de matéria orgânica. O estudo proposto foi executado por meio de: (a) estudos preliminares; (b) testes preliminares; (c) experimento I, empregando ozônio sem variação da alcalinidade afluente; (d) experimento II, empregando ozônio com variação da alcalinidade afluente; (e) experimento III, empregando ozônio combinado com peróxido de hidrogênio sem variação da alcalinidade afluente; (f) verificação da desinfecção; (g) análise crítica dos resultados. Fez-se comparação entre os parâmetros de análise, a dosagem de ozônio consumida e o tempo de contato e entre a qualidade do efluente ozonizado e os critérios de qualidade para reuso de efluentes, permitindo chegar as seguintes conclusões: (i) a maior parte do teor de ozônio consumido durante a ozonização é consumido nos primeiros 5 minutos; (ii) o consumo de ozônio pode ser melhor entendido analisando-se a variável dose instantânea aplicada de ozônio; (iii) o comportamento da transferência de ozônio é influenciado por três fatores: hidrodinâmica do reator, quantidade de ozônio, disponível para reagir e características do efluente; (iv) a variação no pH indica o grau de oxidação atingido no processo; (v) a presença de nitrato favorece a oxidação;(vi) a ozonização é um processo muito eficiente para desinfetar efluentes. A inativação de coliformes totais e fecais atingiu 7,51 e 6,98 Log, respectivamente; (vii) a massa de ozônio por tempo regula a taxa de remoção de DQO enquanto a dose média, a eficiência de remoção de DQO; (viii) Com o consumo de 32,46 +/- 8,19 mg/L de ozônio em 25 minutos de ozonização chegou-se a remoção média de DQO e Turbidez de 48,33 mais ou menos 2,90% e 89,22 +/- 0,35%, respectivamente; (ix) a adição de peróxido de hidrogênio melhorou significativamente a eficiência de remoção de DQO e de carbono. Sem adicionar o peróxido de hidrogênio, precisou-se de 25 minutos de ozonização para se atingir cerca de 25% de remoção de DQO; enquanto que, adicionando peróxido de hidrogênio na razão O3/H2O2 de aproximadamente 0,30, este tempo foi de apenas 10 minutos e a remoção de carbono total dobrou de valor; (x) o efluente ozonizado deve passar por tratamento adicional antes de ser lançado no corpo receptor ou ser reusado. / In this research an experimental study of the potentiality of employment of the ozonization was accomplished after anaerobic treatment, in what refers the dose, time of contact, alkalinity, application combined with hydrogen peroxide, amount of consumed ozone and oxidation of organic matter. The proposed study was executed by means of: (a) preliminary studies; (b) preliminary tests; (c) experiment I, using ozone without variation of the affluent alkalinity; (d) experiment II, using ozone with variation of the affluent alkalinity; (and) experiment III, using ozone combined with hydrogen peroxide without variation of the affluent alkalinity; (f) verification of the disinfection; (g) critical analysis of the results. The results were analyzed by means of graphs, it was make itself comparison among analysis parameters, transferred ozone dose and time of contact and among quality of ozonized effluent and quality criterion for effluent reuse. Permitting arrive the following conclusions: (i) the most of the content of consumed ozone during the ozonization is consumed in the first 5 minutes; (ii) the consumed ozone can be better understood analyzing itself the variable applied instant ozone dose; (iii) the behavior from the ozone transference is influenced by three factors: hydrodynamic of the reactor, quantity of ozone available to react and characteristics of the effluent; (iv) the change in pH shows the reached rank of oxidation in the process; (v) the presenceof nitrate favors to oxidation; (vi) the ozonization is a very efficient process to disinfect effluent. The inativation of total and fecal coliforms reached 7,51 and 6,98 Log, respectively; (vii) the mass of ozone controls the rate of COD removal while the medium dose controls the efficiency of COD removal; (viii) with the consumption of ozone of 32,46 +/- 8,19 mg/L in 25 minutes of ozonization, it arrived COD and turbidity medium removals of 48,33 +/- 2,90% and 89,22 +/- 0,35%, respectively; (ix) the addition of hydrogen peroxide improved significantly the efficiency of COD and carbon removal. Without adding hydrogen peroxide, it was needed 25 minutes of ozonization to reach about 25% of COD removal; while that, adding hydrogen peroxide in reason O3/H2O2of approximately 0,30, this time was only 10 minutes and total carbon removal double; (ix) the ozonized e to be submitted an additional treatment before of its discharge in the surface water or its reused.
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Proposta de um modelo de gestão integrada de águas urbanas em escala de lote residencial: alcances e limitações / Proposal for a model of integrated management of urban water scale of residential lot: scope and limitationsRicardo Camilo Galavoti 24 February 2012 (has links)
Esta pesquisa teve como objetivo principal o desenvolvimento de contribuições de natureza técnica para uma proposta de política pública visando a criação de um novo modelo de gestão de águas urbanas, por meio do desenvolvimento e implantação, em escala de lote residencial, de um sistema de gestão integrada da drenagem seletiva e aproveitamento de águas pluviais, e reúso de esgotos sanitários tratados, denominado \"Sistema de Drenagem e Reúso Inteligente\" (SiDRI). A pesquisa foi realizada em um sítio experimental peri- urbano, chamado de Lote Experimental Peri-Urbano, provido de cobertura de telhas de zinco, e os dados resultantes comparados com dados gerados em estudo prévio realizado em outros dois sítios experimentais urbanos, a saber: Laboratórios de Apoio ao Ensino de Graduação-1 e 2 (LAEGs-1 e 2), na área 1 do Campus-1 da USP de São Carlos, respectivamente providos de: telhas prensadas à base de embalagens longa vida recicladas (LAEG -1); e Cobertura Verde Leve CVL (LAEG-2). Para o manejo das águas urbanas em escala de lote residencial foram considerados dois tipos principais de contribuições: 1) Águas advindas de esgotamento sanitário, tratadas em uma fossa séptica biodigestora (FSB) modelo EMBRAPA, e 2) Águas pluviais, captadas e tratadas em um Sistema de Aproveitamento de Águas Pluviais (SAP), cuja concepção básica foi a mesma para os três sítios experimentais. Foram realizadas para o Telhado de Zinco seis séries amostrais consecutivas, para seis eventos de precipitação, em sete pontos de amostragem do SAP, e analisadas 38 (trinta e oito) variáveis de qualidade de água físico-químicas e biológicas. A análise dos resultados, comparada aos demais telhados, sugeriu, face à legislação pertinente, um aproveitamento predominantemente para fins não- potáveis, e desde que mediante prévia desinfecção das águas pluviais. Para a FSB, 15 campanhas de amostragem foram realizadas alternadamente, cujos resultados apontaram uma possibilidade ainda limitada de reuso para o esgoto tratado. Apesar dos resultados do presente estudo indicarem que o novo modelo de gestão de águas urbanas requer adequações, oferecem uma possibilidade de solução para desafios antigos e atuais na gestão das águas urbanas, tendo fornecido elementos para a configuração de uma nova política pública aqui chamada de \"Política Nacional de Gestão de Águas Urbanas\", a qual apresenta interfaces com políticas anteriores, como a Lei das Águas. / This research aimed as its main goal the development of contributions to a proposal for a public policy to the creation of a new urban waters management model, through the development and establishment, at urban lot scale, of an integrated selective drainage system and rainwater use, and reuse of treated domestic sewage, named \"Smart Drainage and Reuse System\" (SD&RS). The research was accomplished at an experimental peri-urban site, named Peri-Urban Experimental Lot, provided by a cover of zinc roof tiles, and its resulting data compared to data generated on a previous study accomplished at another two experimental sites, namely: Undergraduate Learning Support Laboratory-1 and 2 (LAEGs-1 and 2), respectively provided of: compressed tiles made of recycled long-life milk packaging (LAEG-1); and extensive green roof (LAEG-2). For handling of urban waters in residential lot scale, two main types of contribution were considered: 1) Waters from sanitary sewers, treated in a Septic Cesspool Biodigester (SCB) EMBRAPA Model, and 2) Rainwater, collected and treated in a Rainwater Use System (RUS), whose basic conception was the same for the three experimental sites. For the zinc roof, 6 (six) successive sampling series were performed, for 6 (six) rainfall events, in 7 (seven) sampling points of the Rainwater Use System (RUS), and 38 (thirty-eight) physicochemical and biological water quality variables were analysed. The results analysis, compared to the other roofs, suggested, according to the related regulations, a predominant use to non-potable purposes, and since previous rainwater disinfection. For the SCB, 15 (fifteen) alternated sampling series were performed, whose results indicated a still limitated reuse possibility for sanitary sewage. Despite of the results of the present study indicated that the new urban waters management model requires suitability, they offer a possibility of solution to old and actual challenges in urban waters management, since they provided elements for the design of a new public policy named here \"Urban Waters Management Federal Policy\", which presents interfaces with previous policies, like the Water Law.
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Pathogen Removal in Natural Wastewater Treatment and Resource Recovery Systems: Solutions for Small Cities in an Urbanizing WorldVerbyla, Matthew Eric 17 November 2015 (has links)
Sanitation, renewable energy, and food security are among the most pressing global development needs of the century, especially for small cities with rapid population growth. Currently, 53% of the world’s population either lacks access to improved sanitation or discharges fecal waste to the environment without treatment. Furthermore, 80% of food consumed in developing regions is produced by 500 million small farms, and while many of them are still rain-fed, irrigated agriculture is increasing. The post-2015 Sustainable Development Goals, recently adopted by the United Nations, include targets to address the water-energy-food nexus. Wastewater reuse in agriculture can be an important solution for these goals, if it is done safely. Globally, 18 – 20 million hectares of agricultural land are irrigated with wastewater, but much is untreated, unregulated, or unsanctioned, causing concerns and uncertainty about health risks.
There is a need to better understand pathogen removal in natural and non-mechanized wastewater treatment systems, such as waste stabilization ponds (WSPs) and upflow anaerobic sludge blanket (UASB) reactors, which are commonly used in small cities and towns. Riverbank filtration (RBF) is also a natural technique used by farmers in developing countries to treat surface water polluted with untreated sewage, but pathogen removal in these systems has seldom been assessed in developing countries. The focus of this dissertation is on pathogen removal in natural and non-mechanized wastewater treatment and reuse systems, to evaluate the health implications of water reuse for irrigation, with the following three objectives: 1) assess the current understanding of virus removal in WSP systems through a systematic review of the literature; 2) measure the removal of viruses and their association with particles in systems with WSPs, UASB reactors, or both; and 3) assess the fate and transport of pathogens and fecal indicators in wastewater treatment systems with direct and indirect reuse for irrigation to estimate microbial risks.
To advance the understanding of virus removal in WSP systems, a comprehensive analysis of virus removal reported in the literature from 71 different WSP systems revealed only a weak to moderate correlation of virus removal with theoretical hydraulic retention time (HRT). For each log10 reduction of viruses a geometric mean of 14.5 days of retention was required, but the 95th percentile of the data analyzed was 54 days. Also, whereas virus-particle association and subsequent sedimentation has been assumed to be an important removal mechanism for viruses in WSPs, the literature review revealed a lack of evidence to confirm the validity of this assumption.
The association of human adenovirus (AdV) with wastewater particles was assessed in five full-scale wastewater treatment systems in Bolivia, Brazil, and the United States (two with only WSPs, two with a UASB reactor and WSPs, and one with only UASB reactors). A mesocosm study was also conducted with WSP water from one of the full-scale systems, and some samples were also analyzed for pepper mild mottle virus (PMMoV), F+ coliphage, culturable enterovirus (EV), norovirus (NoV), and rotavirus (RV). Results indicate that WSPs and UASB reactors affect virus-particle associations in different ways, which may differ for different viruses. In UASB reactor effluent, PMMoV was more associated with particles <180 >µm, showed no indication of settling in subsequent ponds, and appeared to degrade in pond sediments after 5 days. In contrast, AdV in UASB reactor effluent was associated with small and large particles, and in subsequent ponds, particle-associated AdV showed evidence of possible settling or more rapid decay at the water surface. AdV and culturable EV were also more volumetrically-concentrated in UASB reactor sludge than they were in untreated sewage, WSP water, UASB effluent, and WSP sediments, indicating that the reactors may cause these viruses to become entrapped and concentrated in granular sludge. Some viruses may be removed in the sludge, but others exit the reactors in solution and attached to particles. The resuspension of pellets from centrifuged UASB reactor sludge samples in an eluant buffer indicated reversible AdV association with granular sludge, but some associations with particles in solution may not be reversible.
The fate and transport of pathogens and fecal indicators was assessed in Bolivia for two WSP systems with direct reuse for irrigation, and one on-farm RBF system used to treat surface water polluted by untreated sewage. In the WSP systems, despite HRTs of 10 days, pathogen and fecal indicator removal was generally ≤1-log10, possibly due to overloading and short-circuiting from sludge accumulation. The RBF system provided removals on the order of 2-log10 for protozoan parasites, 3-log10 or more for viruses, and 4-log10 or more for bacteria. The use of RBF also reduced cumulative estimated health burdens associated with irrigated lettuce. Irrigation of lettuce with untreated river water caused an estimated disease burden that represents 37% of the existing burden from acute diarrhea in Bolivia; when RBF was used, this decreased to only 1.1%, which is not epidemiologically-significant, and complies with the World Health Organization guidelines. Ratios of concentrations of microorganisms in irrigation water to their respective concentrations in soil or crops were calculated, to assess transfer from irrigation water to soil or crops. These ratios (with units mL g-1) were generally < 0.1 mL g-1 for coliphage, between 1 and 100 mL g-1 for Giardia and Cryptosporidium, and generally between 100 and 1,000 mL g-1 for helminth eggs. Higher ratios could indicate more efficient transfer from water to soil or crops, longer persistence in soil or on crops, or slower leaching away from soil or crops.
The results from this research demonstrate that pathogen removal in full-scale natural wastewater treatment systems happens via complex mechanisms that vary with respect to pathogen type, treatment systems configuration, and other environmental and operational parameters. Future research and innovation efforts should focus on the use of a combination of natural and non-mechanized technologies, surface-flow systems (e.g., WSPs) and subsurface systems (e.g., RBF), applied at both semi-centralized (e.g., wastewater treatment plant) and decentralized levels (e.g., on farms), to evaluate how this affects the efficiency and resiliency of pathogen removal. Also, future research is needed to further elucidate reasons for the observed differences in virus-particle associations in natural wastewater treatment systems.
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Water quality dynamics in an experimental serial-use raceway and its effects on growth of South African abalone, Haliotis midaeNaylor, Matthew Aubrey January 2012 (has links)
An understanding of species specific water quality requirements is essential for efficient production of aquaculture products, an aspect not well documented for the land-based culture of the South African abalone, Haliotis midae. In order for the industry to remain competitive in international markets, efficient use of water supplies and the development of water reuse technology is needed. This study assessed the changes in water quality between tanks in a tiered serial-use raceway in relation to accumulated biomass and water flow and estimated the flow index (FI) (L h⁻¹ kg⁻¹) at which growth becomes significantly affected. The effect of dietary protein level, supplementation of pure oxygen and addition of sodium hydroxide (NaOH⁻) on water quality and fundamental production parameters in the serial-use raceways was also assessed. The serial-use raceways were used as a tool to create a range of water quality conditions at which the growth, feed conversion ratio (FCR) and condition factor (CF) of "cocktail" size (60 – 70 mm) H. midae could be monitored. The metabolic activity of the abalone resulted in a deterioration in water quality between tanks in series. pH (r² = 0.99; p < 0.001) and dissolved oxygen concentration (r² = 0.99; p < 0.001) were positively correlated with flow index (pH = 7.38 FI°·°² ; dissolved oxygen = 6.92 FI°·°⁴), while free ammonia nitrogen (FAN) (r² = 0.99, p < 0.001) and nitrite (NO²⁻ - N) (r² = 0.93, p < 0.001) were negatively correlated with flow index (FAN = 8.02 FI⁻°·⁷¹). Nitrite concentrations increased over time indicating colonisation of Nitrosomonas bacteria on the basket surfaces. A flow index of 7.2 – 9.0 L h⁻¹ kg⁻¹ was estimated as the minimum to avoid significant reductions in weight and shell length gain and increases in FCR values. Total ammonia nitrogen (TAN) and FAN concentrations were significantly correlated to dietary protein (P) (t = 6.63, p < 0.0001 and t = 6.41, p < 0.0001, respectively) and flow index (t = 5.42, p < 0.0001 and t = 3.9, p < 0.0002, respectively) and could be estimated using the models TAN = 9.73 P – 110.3 log (FI), and FAN = 0.132 P – 1.10 log (FI). Mean FAN concentrations were 67 and 41 % lower in tanks fed a diet containing 22 and 26 % protein respectively, when compared to tanks fed a 33 % protein diet. Supplementation with pure oxygen (103 ± 8 % saturation) improved shell length gain (t = 3.45, p = 0.026) in abalone exposed to high FAN (2.43 ± 1.1 μg L⁻¹) and low pH (7.6 ± 0.13), relative to a treatment with no oxygen supplementation (92 ± 6 % saturation). Addition of a sodium hydroxide solution resulted in elevated mean pH in treatment raceways when compared to control raceways. The increased pH resulted in significantly higher weight gain (g abalone⁻¹) (F₁·₁₂ = 4.51; p = 0.055) and shell length gain (mm abalone⁻¹) (F₁·₁₂ = 4.56; p = 0.054) at an α-error level of < 5.5 %. In two trials, weight gain and shell length gain were significantly correlated to pH (p < 0.001), and multiple regression of pH, dissolved oxygen and FAN consistently revealed pH to be the best predictor of growth. It is therefore suggested that decreasing pH is the first limiting water quality variable for abalone in serial-use raceways. As a decrease in water pH is linked to respiration by the abalone and subsequent increase in dissolved carbon dioxide (CO₂) concentration, future studies should examine the effects of CO₂ on H. midae metabolic rate, calcification rate and health. The results of this study will contribute toward our understanding of the specific water quality requirements for H. midae in commercial aquaculture systems, and influence the design and management procedures for abalone water reuse systems.
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Bioprocess development for removal of nitrogenous compounds from precious metal refinery wastewaterManipura, Walappuly Mudiyanselage Janakasiri Aruna Shantha Bandara January 2008 (has links)
Removal of nitrogenous compounds from precious metal refinery (PMR) wastewater is important in terms of avoiding eutrophication (environmental protection), metal recovery (increased overall process efficiency and value recovery) and reuse of treated water (maximum use of natural resources). Extreme pH conditions (4 to 13 depending on the wastewater stream), high chemical oxygen demand (> 10,000 mg/I), numerous metals and high concentrations of those metals (> 20 mg/l of platinum group metals) in the wastewater are the main challenges for biological removal of nitrogenous compounds from PMR wastewater. Nitrogenous compounds such as NH₄⁺-N and N0₃-N are strong metal ligands, which make it difficult to recover metals from the wastewater. Therefore, a bioprocess was developed for removal of nitrogenous compounds from carefully simulated PMR wastewater. A preliminary investigation of metal wastewater was carried out to determine its composition and physico-chemical properties, the ability to nitrify and denitrify under different pH conditions and denitrification with different carbon Source compounds and amounts. Even at pH 4, nitrification could be carried out. A suitable hydraulic retention time was found to be 72 hours. There was no significant difference between sodium acetate and sodium lactate as carbon sources for denitrification. Based on these results, a reactor comparison study was carried out using simulated PMR wastewater in three types of reactors: continuously stirred tank reactor (CSTR), packed-bed reactor (PBR) and airlift suspension reactor (ALSR). These reactors were fed with 30 mg/l of Rh bound in an NH₄⁺ based compound (Claus salt: pentaaminechlororhodium (III) dichloride). Total nitrogen removal efficiencies of > 68 % , > 79 % and > 45 % were obtained in the CSTR, PBR and ALSR, respectively. Serially connected CSTR-PBR and PBR-CSTR reactor configurations were then studied to determine the best configuration for maximum removal of nitrogenous compounds from the wastewater. The PBR-CSTR configuration gave consistent biomass retention and automatic pH control in the CSTR. Ammonium removal efficiencies > 95 % were achieved in both reactors. As poor nitrate removal was observed a toxicity study was carried out using respirometry and the half saturation inhibition coefficients for Pt, Pd, Rh and Ru were found to be 15.81, 25.00, 33.34 and 39.25 mg/l, respectively. A mathematical model was developed to describe the nitrogen removal in PMR wastewater using activated sludge model number 1 (ASMl), two step nitrification and metal toxicity. An operational protocol was developed based on the literature review, experimental work and simulation results. The optimum reactor configuration under the set conditions (20 mg/I of Rh and < 100 mg/I of NH₄⁺-N) was found to be PBR-CSTR-PBR process, which achieved overall NH₄⁺-N and N0₃⁻-N removal efficiencies of > 90 % and 95 %, respectively. Finally, a rudimentary microbial characterisation was carried out on subsamples from the CSTR and PBRsecondary. It was found that the CSTR biomass consisted of both rods and cocci while PBRsecondary consisted of rods only. Based on these experimental works, further research needs and recommendations were made for optimisation of the developed bioprocess for removal of nitrogenous compounds from PMR wastewater.
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Onsite greywater reuse as a water conservation method: a case study of Lepelle-Nkumpi Local Municipality, Limpopo Province of South AfricaMashabela, Karabo January 2015 (has links)
Thesis (MSc. (Geography and Environmental Science)) -- University of Limpopo, 2015. / Fresh water is a finite and vulnerable resource, essential to sustain life, development and the environment. Growth in population and economic activities have contributed to water scarcity, which is a frequent challenge in rural and township communities in South Africa. This study aimed at investigating onsite greywater reuse as a water conservation method in Lepelle-Nkumpi local municipality, Limpopo province. The study described the socio-economic characteristics, assessed the accessibility and availability of water supply, and ascertained the coping mechanisms for water scarcity as well as the perceptions and reuse of greywater. Four percent respondents each were selected from two settlements, namely, Mashite village and Lebowakgomo township (Zone F). Mashite village had a population size of 5314 people (1231 households) and Lebowakgomo Zone F had 5903 people and (1924 households). A systematic random sampling method was used to select the required households from the two settlements. Both open and close ended questionnaires were used. A Geographical Positioning System was also used to collect the absolute location of available taps in the study area. Data collected were analysed using SPSS version-22 and Arc GIS 10.1.
The study found out that the socio-economic characteristics of importance on onsite greywater reuse included highest qualification, household size and employment status, but they varied in these two areas. In Mashite village the majority of the respondents went to secondary school (59%) as compared to Lebowakgomo Zone F where the majority (72%) attained tertiary qualification. Household size mean in Mashite is 6.18 as compared to Lebowakgomo Zone F (2.77). Sixty four percent of respondents in Mashite village were unemployed, whereas in Lebowakgomo 69% were employed. Water usage in the two areas differed; in Mashite village where they use less water (250 to 840 litres) as compared to Lebowakgomo Zone F, where more water is used (5900 to 8001 litres). In Mashite village, 87% of the respondents could not access water due to inaccessibility of taps and unavailability of water as compared to Lebowakgomo zone F (100%). It was also found that the Mashite community sometimes go for a period of two to three months without tap water whereas in Lebowakgomo water was comparatively regular. As a result both communities resorted to rainwater harvesting and greywater reuse. Seventy six percent (76%) of respondents in Mashite village and 30% of the respondents in
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Lebowakgomo Zone F harvested rainwater as a coping mechanism of water scarcity. Perceptions of greywater reuse were higher (76%) in Lebowakgomo Zone F compared to Mashite village (49%). A higher percentage of Mashite village respondents (98%) reuse greywater compared to Lebowakgomo Zone F respondents (59%). Both areas use greywater as water conservation method. These results reinforce the potential of domestic greywater reuse as an alternative for freshwater requirement. Greywater reuse as a water conservation method especially in villages can be used to alleviate the extent of water scarcity. / National Research Foundation (NRF)
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