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Avalia??o da efici?ncia da remo??o de mat?ria org?nica e microbiol?gica de tr?s sistemas de lagoas de estabiliza??o em s?rie na Grande Natal-RN: Beira Rio, Jardim Lola I e Jardim Lola IIVale, Milton Bezerra do 30 November 2006 (has links)
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Previous issue date: 2006-11-30 / Waste stabilization ponds are the main technology in use for domestic sewage treatment in Rio Grande do Norte State (RN), northeast Brazil. The are around 80 systems, constructed mainly by municipal city halls, being series comprised by a primary facultative pond followed by two maturation ponds the most used configuration. Due to problems related with the production and destination of sludge and generation of bad odors, the designers have avoided the use of anaerobic lagoons. The majority of systems are rarely monitored to verify their efficiencies and to get new project parameters for future designing. This work has as purpose to make a diagnosis of efficiency of three series of waste stabilization pond series (WSPS) of Jardim Lola 1, Jardim Lola 2 and Beira Rio, located in the North Zone of the city of the Natal/RN, treating domestic raw sewage, on the removal of organic matter and thermotolerant coliform, comparing the operational conditions of the systems this inside of the bands foreseen in the project, through parameters BOD5, QOD, thermotolerant coliforms, dissolved oxygen, pH, temperature, ammoniac nitrogen, total and suspended solids. The work was carried through in the WSPS, all constituted by a primary facultative pond followed by two maturation ponds. Socioeconomic characteristics of population are predominantly low and all the plants are very near of the contributing basins. The series were monitored from of May the November of 2002, totalizing 20 collections of grab samples of raw sewage and ponds effluents between 8:00 and 9:50 h. The main aspect to be detached by the results was the great concentration of organic matter (BOD and COD) and microorganisms the raw sewage which were around two times more concentrated than those values foreseen one in project. Considering all series the highest removals of organic matter were observed in system Beira Rio (84 and 78% of BOD and COD, respectively), which presented high hydraulic detention time (TDH = 89 days). On the other hand, Jardim Lola 1 and Jardim Lola 2 presented a much lower values of HDT (36 days and 18 days respectively) and their removals of BOD and COD were the same (76% and 60%, respectively). The Beira Rio WSPS, was the most efficient verified in relation to solids and ammonia, proving the great influence of the operational variables such as HDT and applied surface organic loadings on the performance of pond series. Although the treatment plants have reached efficiencies of thermotolerant coliforms around 99,999%, the concentrations in the final effluent can be considered very high for launching in aquatic bodies, particularly those produced by Jardim Lola 1 and Jardim Lola 2 series / O sistema de lagoas estabiliza??o ? o tipo de tratamento de esgoto dom?stico mais utilizado no Estado do Rio Grande do Norte, contando com 80 sistemas, constru?dos principalmente pelas prefeituras municipais, sendo o sistema de lagoas em s?rie constitu?das de lagoa facultativa prim?ria seguida de lagoas de matura??o um dos mais utilizados. Devido aos problemas relacionados com a produ??o e destino de lodo e gera??o de maus odores, os projetistas t?m evitado o uso de lagoas anaer?bias. Vale salientar que tais sistemas de lagoas comumente n?o s?o monitorados de forma adequada para verificar suas efici?ncias e obter dados para futuros projetos. Este trabalho tem como finalidade fazer um diagn?stico da efici?ncia de tr?s s?ries de lagoas de estabiliza??o na grande Natal, Jardim Lola 1, Jardim Lola 2 e Beira Rio, na remo??o de mat?ria org?nica e coliformes termotolerantes e, verificar se as condi??es operacionais dos sistemas esta dentro das faixas previstas no projeto, atrav?s dos par?metros DBO5, DQO, coliformes termotolerantes, oxig?nio dissolvido, pH, temperatura, nitrog?nio amoniacal, s?lidos totais e suspensos. Os sistemas estudados s?o constitu?dos por uma lagoa facultativa prim?ria seguida de duas lagoas de matura??o, que atendem a uma popula??o predominante de baixa renda a qual est? bem pr?xima da esta??o de tratamento de esgoto. As tr?s ETE s foram monitoradas no per?odo de maio a novembro de 2002, totalizando 20 coletas de amostras pontuais de esgoto bruto e efluentes das lagoas entre 8:00 e 9:50 h. Os principais aspectos a serem destacados no monitoramento foram a grande concentra??o de mat?ria org?nica e microrganismos nos esgoto brutos afluentes em rela??o ao previsto em projeto. Considerando toda a s?rie as maiores remo??es de mat?ria org?nica ocorreram no sistema Beira Rio (84 e 78% de DBO e DQO, respectivamente), que apresentava um TDH de 89 dias enquanto que os sistemas de Jardim Lola 1 e 2 eram de 36 dias e 18 dias respectivamente, foram determinadas remo??es semelhantes de DBO (76%) e de DQO em torno de 60%. O sistema Beira Rio tamb?m foi o mais eficiente na remo??o de s?lidos e de nitrog?nio amoniacal, comprovando a grande influ?ncia das vari?veis operacionais tais como tempo de deten??o hidr?ulica e carga org?nica aplicada, no desempenho dos sistemas de tratamento. Embora as esta??es de tratamento tenham atingido efici?ncias de coliformes termotolerantes em torno de 99,999%, as concentra??es nos efluentes finais podem ser consideradas muito elevadas para lan?amento em corpos aqu?ticos, particularmente as de Jardim Lola 1 e 2
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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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Indicadores microbiológicos de tratamento conjugado de lixiviado de aterro sanitário e esgoto sanitário em lagoas de estabilização rasasOliveira, Alinne Gurjão de 22 February 2013 (has links)
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Previous issue date: 2013-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Treatment conjugate landfill leachate and sewage is widely used for reducing the
concentration leachate pollutants. Stabilization ponds are the simplest processes,
low cost and maintenance, used as alternatives for wastewater treatment. This study
aimed to characterize the microbial community present in conjugate treatment in
natura of landfill leachate and sewage in stabilization ponds. The experimental
system was designed, and monitored at the Experiment Station Biological Sewage
Treatment (EXTRABES) State University of Paraiba, Campina Grande - PB, Brazil (7
° 13'11'' South, 35 ° 52 '31'' West and 550 m above sea level), consisting of four
shallow stabilization ponds in series: a facultative pond, followed by three maturation
ponds. A daily, the necessary volume of the substrate, from mixing 1% of landfill
leachate, in natura, more 99% sewage, used for feeding the series of stabilization
ponds. The average removal efficiency of thermotolerant coliforms and helminth eggs
was 99.78% and 100%, respectively. The average concentration of the algal mass
expressed as chlorophyll was 1032.6 ug / L. 29 taxa were identified phytoplankton
included in six taxonomic classes: Cyanobacteria, 8 genres; Chlamydophyceae, 8
genres; Chlorophyceae, 9 genres; Euglenophyceae, 4 genres; Bacillariophyceae, 3
genres, and Zignemaphyceae, 1 gender. / O tratamento conjugado de lixiviado de aterro sanitário e esgoto sanitário é
amplamente utilizado para redução da concentração de poluentes dos lixiviados.
Lagoas de estabilização são os processos mais simples, de baixo custo e
manutenção, utilizados como alternativas para tratamento de águas residuárias. O
presente trabalho objetivou caracterizar a comunidade microbiana presente no
tratamento conjugado de lixiviado de aterro sanitário in natura e esgoto sanitário em
lagoas de estabilização. O sistema experimental foi projetado, construído e
monitorado nas dependências físicas da Estação Experimental de Tratamentos
Biológicos de Esgotos Sanitários (EXTRABES) da Universidade Estadual da
Paraíba, Campina Grande PB, Brasil, (7°13 11 Sul, 35°52 31 Oeste e 550 m
acima do nível do mar), constituindo-se de quatro lagoas de estabilização rasas em
série, sendo uma lagoa facultativa, seguida de três lagoas de maturação. Foi
preparado diariamente, o volume necessário de substrato, a partir da mistura de 1%
de lixiviado de aterro sanitário, in natura, mais 99% de esgoto sanitário, utilizado
para a alimentação da série de lagoas de estabilização. A eficiência média de
remoção de coliformes termotolerantes e ovos de helmintos foi de 99,78% e 100%,
respectivamente. A concentração média da massa de algas expressa em clorofila a
foi de 1032,6 ug/L. Foram identificados 29 táxons fitoplanctônicos incluídos em seis
classes taxonômicas: Cyanobacteria, 8 gêneros; Chlamydophyceae, 4 gêneros;
Chlorophyceae, 9 gêneros; Euglenophyceae, 4 gêneros; Bacillariophyceae, 3
gêneros; e Zignemaphyceae, 1 gênero.
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UtilizaÃÃo de Reatores AerÃbios como PÃs-Tratamento de Lixiviado Antigo Tratado por Lagoas de EstabilizaÃÃo / Use of Aerobic Reactors as Post-Treatment of leachate by Old Treaty Stabilization PondsAntonio Lima Farias Filho 03 August 2010 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Os sistemas de lagoas de estabilizaÃÃo, bastante presentes em aterros sanitÃrios normalmente nÃo sÃo suficientes para o atendimento aos padrÃes ambientais de descarte de lixiviado tratado em Ãguas superficiais. Este trabalho avaliou o emprego das tecnologias aerÃbias do tipo reator aerado submerso (RAS) e reator em batelada seqÃencial (RBS) como opÃÃes de pÃs-tratamento para lixiviado antigo prÃ-tratado em lagoas de estabilizaÃÃo. A coleta do lixiviado se deu na saÃda da Ãltima lagoa de estabilizaÃÃo do sistema de tratamento de lixiviado (duas anaerÃbias em sÃrie, seguidas de uma facultativa) localizadas no Aterro SanitÃrio Metropolitano Oeste (ASMOC), municÃpio de Caucaia, RegiÃo Metropolitana de Fortaleza, estado do CearÃ. Inicialmente foi realizada uma caracterizaÃÃo fÃsico-quÃmica do lixiviado efluente e verificaÃÃo do atendimento aos padrÃes de descarte. O RAS foi operado em cinco fases, sendo divididas entre esgoto sintÃtico e lixiviado, este Ãltimo testado com e sem diluiÃÃo. Avaliou-se o efeito da adiÃÃo de fonte externa de carbono, etanol, para a fase em que o reator era alimentado com lixiviado sem diluiÃÃo. O RBS foi confeccionado em acrÃlico, em formato cilÃndrico, com um volume Ãtil de 5,0L, sendo inicialmente estudado o tempo de operaÃÃo de cada ciclo de 24 horas. Posteriormente, foram avaliados no RBS os tempos totais de ciclo de 12 e 48 horas, alÃm do efeito da adiÃÃo de etanol no desempenho do reator. Os reatores foram instalados no LaboratÃrio de Saneamento (Labosan) do Departamento de Engenharia HidrÃulica e Ambiental (DEHA) da Universidade Federal do Cearà (UFC). Eles foram operados na faixa mesofÃlica, com temperatura ambiente prÃxima de 27ÂC. Em relaÃÃo ao lixiviado tratado, os valores encontrados na caracterizaÃÃo fÃsico-quÃmica confirmam a recalcitrÃncia e complexidade do lixiviado, indicando que apenas as lagoas de estabilizaÃÃo, nÃo atendem plenamente os padrÃes de descarte. A presenÃa de compostos recalcitrantes e tÃxicos no lixiviado afluente ao RAS durante um dos perÃodos de investigaÃÃo causou diminuiÃÃo na remoÃÃo de DQO, mostrando efeito inibitÃrio nos microrganismos presentes no inÃculo. Entretanto, em outra fase de investigaÃÃo, tanto o RAS quanto o RBS se mostraram eficientes e estÃveis na remoÃÃo de DQO e nitrogÃnio amoniacal, mesmo tratando lixiviado sem diluiÃÃo. A adiÃÃo de etanol como fonte externa de carbono foi benÃfica para suprir as necessidades metabÃlicas microbianas, fazendo aumentar tanto a eficiÃncia global do RAS e RBS em termos de remoÃÃo de matÃria orgÃnica (DQO), assim como na estabilidade operacional dos mesmos. O RAS e o RBS foram tambÃm bastante eficientes no processo de nitrificaÃÃo. O estudo no RBS com os tempos de ciclo de 12, 24 e 48 h revelaram que nÃo houve diferenÃa entre os tempos em relaÃÃo à remoÃÃo dos constituintes analisados, fazendo com que se considerasse 12 h como tempo Ãtimo de ciclo, de forma a minimizar os custos com volume do reator e tempo de aeraÃÃo. Como conclusÃo geral do experimento pode-se dizer que o tratamento biolÃgico aerÃbio, tanto utilizando reatores aerados submerso (RAS) quanto reatores em batelada seqÃencial (RBS), pode ser considerado uma boa alternativa para o pÃs-tratamento de lixiviado antigos provenientes de sistemas de lagoas de estabilizaÃÃo, mas ainda requer adequaÃÃes operacionais ou associaÃÃes com processos fÃsico-quÃmicos ou de oxidaÃÃo avanÃados para o enquadramento de todos os constituintes. / The system of stabilization ponds, which is often present in landfills, is usually not efficient to meet environmental standards for disposal of treated leachate on surface waters. This study evaluated the use of submerged aerated reactor (SAR) and sequencing batch reactor (SBR) as post-treatment options for old leachate pre-treated in waste stabilization ponds. The leachate collection took place at the outflow of the last stabilization pond of the treatment system (two anaerobic em series, followed by a facultative pond) located in West Metropolitan Landfill (ASMOC), Caucaia municipality, metropolitan region of Fortaleza, Cearà state. A physical-chemical characterization of the leachate effluent was performed to verify the compliance to reach disposal standards. The SAR was operated in five phases, being divided between synthetic wastewater and leachate, the latter tested with and without dilution. We evaluated the effect of adding an external carbon source, ethanol, for the phase in which the reactor was fed with leachate without dilution. SBR was made of acrylic, in a cylindrical shape with a working volume of 5.0 L and the total time cycle of 24 hours was initially studied. The total time cycles of 12 and 48 hours were also evaluated in the SBR performance, as well as the effect of adding ethanol as carbon source. The reactors were installed at the Laboratory of Sanitation (Labosan) of the Department of Hydraulic and Environmental Engineering (DEHA), Federal University of Cearà (UFC). They were operated in the mesophilic range, with temperature near 27  C. Regarding the treated leachate, the physical-chemical characterization confirmed its recalcitrance and complexity, indicating that only the stabilization ponds did not fully meet the standards of disposal. The presence of recalcitrant and toxic compounds in the leachate influent to the SAR during the investigation period decreased COD removal, showing an inhibitory effect on the microorganisms present in the inoculum. However, in another research phase, both the SAR and SBR were stable and efficient on COD and ammonia removals, even when undiluted leachate was used. The addition of ethanol as external carbon source was beneficial to meet the microbial metabolic needs, increasing both the overall efficiency of SAR and SBR in terms of organic matter removal (COD) and operational stability. The SAR and SBR were also quite efficient in the nitrification process. The study with SBR with cycle times of 12, 24 and 48 h showed no considerable difference amongst the constituent removals, so that 12 h was considered as optimal time cycle in order to minimize the costs with reactor volume and aeration time. As a general conclusion of the experiment we can say that the aerobic biological treatment, using either submerged aerated reactor (SAR) or sequencing batch reactors (SBR), can be considered a good alternative for post-treatment of old leachate pre-treated in stabilization ponds, but still requires operational adjustments and associations with physical-chemical or advanced oxidation processes for accomplish all discharge standards.
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Desempenho de estações de tratamento de esgoto: uma análise de sistemas de lagoas de estabilização de pequeno e médio porte integrada à avaliação da qualidade dos corpos hídricos na UGRHI 12 - Baixo Pardo/Grande / Performance of wastewater treatment plants: an analysis of small and medium wastewater treatment pond systems integrated with evaluation of water bodies quality in UGRHI 12 - Baixo Pardo/GrandeLetícia Franco Leonel 02 September 2016 (has links)
Apesar dos avanços nos índices de coleta e tratamento de esgotos no Estado de São Paulo, ainda existem incertezas sobre a efetividade dos sistemas de tratamento existentes, uma vez que são escassas as informações sobre o desempenho das ETEs em operação no país. Por meio da aquisição e análise de dados de desempenho do sistema, é possível a avaliação do cumprimento da legislação ambiental e a melhoria das condições operacionais, reduzindo, efetivamente, o impacto do lançamento sobre os recursos hídricos. Nesse sentido, o presente trabalho teve como objetivo avaliar estatisticamente o desempenho de lagoas de estabilização - tecnologia de tratamento mais utilizada no Estado de São Paulo - localizadas na UGRHI 12 - Baixo Pardo/Grande, todas com vazão de projeto inferior a 300 L/s, utilizando dados de automonitoramento fornecidos pelos prestadores de serviço. A avaliação compreendeu um período de 10 anos (2005 a 2014) e abrangeu desde os projetos das lagoas até a caracterização dos dados afluentes e efluentes das ETEs, incluindo também o impacto do lançamento dos esgotos tratados nos corpos receptores e a qualidade dos corpos d\'água em escala de bacia hidrográfica, utilizando os dados da rede de monitoramento da CETESB na UGRHI 12. O desempenho das ETEs foi avaliado quanto aos parâmetros DBO, DQO, CT, E. coli, SS, N-amoniacal e P-total, considerando tanto as faixas típicas apontadas na literatura, como o atendimento aos padrões de lançamento e qualidade. Os dados disponibilizados foram bastante heterogêneos, apresentando, em sua maioria, periodicidades de amostragem variáveis e interrupções no monitoramento, o que impediu, em alguns casos, a realização de uma análise mais consistente. As concentrações afluentes de matéria orgânica foram mais elevadas do que os valores usuais expressos na literatura, sendo a causa mais provável o baixo consumo de água aliado ao tipo de amostragem praticado (amostragem simples). De maneira geral, o desempenho das lagoas, considerando as eficiências médias de remoção de DBO e DQO, ficou dentro do esperado, o que não foi suficiente, contudo, para garantir percentuais elevados de conformidade com a legislação do estado de São Paulo, os quais resultaram abaixo de 80% na maioria das ETEs. Quanto às concentrações nos esgotos tratados, o desempenho ficou aquém do esperado, o que implicou no lançamento de efluentes com concentrações elevadas de matéria orgânica, embora de acordo com os padrões de lançamento pelo critério da eficiência de remoção. A avaliação do corpo receptor mostrou que, mesmo se tratando de vazões relativamente baixas, tais lançamentos foram capazes de impactar os cursos d\'água, notadamente aqueles com baixas razões de diluição. Finalmente, em escala de bacia hidrográfica, verificou-se que, nos corpos d\'água da UGRHI 12, ainda permanecem percentuais elevados de desconformidade para P-total e E. coli, contribuindo para esse cenário tanto as fontes de poluição pontuais como as difusas. / Despite advances in wastewater collection and treatment indicators in São Paulo state, there are still uncertainties about the effectiveness of existing treatment systems, since they is little information on the performance of WTPs operating in the country. Throughout the acquisition and analysis of system performance data, it is possible to evaluate the compliance with environmental legislation and improve operating conditions, effectively reducing the impact of the discharge on water resources. In this sense, the present study aimed to evaluate statistically the performance of stabilization ponds - wastewater treatment technology most widely used in São Paulo state - located in UGRHI 12 - Baixo Pardo/Grande, all of them with design flow rates below 300 L/s, using self-monitoring data given by the service providers. The evaluation comprised a period of 10 years (2005-2014), including from the projects of the ponds to the characterization of WTPs influent and effluent data, also incorporating the impact of treated wastewater release in receiving bodies and the quality of water bodies in watershed scale, using the data from CETESB\'s monitoring network in UGRHI 12. The performance of the WTPs was evaluated for BOD, COD, total coliforms, E. coli, suspended solids, ammonia and total phosphorus, considering the typical ranges mentioned in the literature and compliance with discharge and water quality standards. The provided data were quite heterogeneous, most of them presenting variable sampling periodicities and interruptions in monitoring, sometimes hindering a more consistent analysis. The influent\'s concentrations of organic matter were higher than the usual values expressed in the literature, which was most likely caused by low water consumption combined with the type of sampling practiced (single sampling). In general, the ponds\' performance, considering the average BOD and COD removal efficiencies, was as expected, however, such values weren\'t enough to ensure high percentage of compliance with São Paulo\'s environmental legislation, since the percentages were below 80% in most WTPs. Regarding the concentrations in treated wastewater, the performance was less than expected, which resulted in the discharge of effluents with high concentrations of organic matter, even though they were in compliance with discharge standards by the removal efficiency criterion. The evaluation of the receiving stream showed that, even consisting of relatively low flow rates discharges, such releases were able to impact the water bodies, especially those with low dilution ratio. Finally, in watershed scale, it was found that, in UGRHI 12 water bodies, there are still high percentages of non-conformity for total phosphorus and E. coli, contributing to this scenario both point and non-point sources of pollution.
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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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Evolu??o da biodegradabilidade da mat?ria org?nica em um sistema de lagoas de estabiliza??oMeneses, Carla Gracy Ribeiro 13 June 2006 (has links)
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Previous issue date: 2006-06-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Waste stabilization ponds (WSP) have been widely used for sewage treatment in hot climate regions because they are economic and environmentally sustainable. In the present
study a WSP complex comprising a primary facultative pond (PFP) followed by two maturation ponds (MP-1 and MP-2) was studied, in the city of Natal-RN. The main
objective was to study the bio-degradability of organic matter through the determination of the kinetic constant k throughout the system. The work was carried out in two phases. In the first, the variability in BOD, COD and TOC concentrations and an analysis of the relations between these parameters, in the influent raw sewage, pond effluents and in specific areas inside the ponds was studied. In the second stage, the decay rate for organic matter (k) was determined throughout the system based on BOD tests on the influent sewage, pond effluents and water column samples taken from fixed locations within the ponds, using the mathematical methods of Least Squares and the Thomas equation. Subsequently k was estimated as a function of a hydrodynamic model determined from the dispersion number (d), using empirical methods and a Partial Hydrodynamic Evaluation (PHE), obtained from tracer studies in a section of the primary facultative pond corresponding to 10% of its total length. The concentrations of biodegradable organic
matter, measured as BOD and COD, gradually reduced through the series of ponds, giving overall removal efficiencies of 71.95% for BOD and of 52.45% for COD. Determining the
values for k, in the influent and effluent samples of the ponds using the mathematical method of Least Squares, gave the following values respectively: primary facultative pond
(0,23 day-1 and 0,09 day-1), maturation 1 (0,04 day-1 and 0,03 day-1) and maturation 2 (0,03 day-1 and 0,08 day-1). When using the Thomas method, the values of k in the influents and effluents of the ponds were: primary facultative pond (0,17 day-1 and 0,07 day-1), maturation 1 (0,02 day-1 and 0,01 day-1) and maturation 2 (0,01 day-1 and 0,02 day-1). From the Partial Hydrodynamic Evaluation, in the first section of the facultative pond corresponding to 10% of its total length, it can be concluded from the dispersion number
obtained of d = 0.04, that the hydraulic regime is one of dispersed flow with a kinetic constant value of 0.20 day-1 / Lagoas de estabiliza??o t?m sido utilizadas para tratamento de efluentes em regi?es de clima quentes apresentando viabilidade econ?mica e ambiental. No presente
trabalho foi estudado um sistema de lagoas de estabiliza??o, na cidade do Natal, constitu?do por uma lagoa facultativa prim?ria (LFP) seguida de duas lagoas de matura??o
(LM1 e LM2) e tem como objetivo o estudo da biodegradabilidade da mat?ria org?nica atrav?s da determina??o da constante cin?tica k ao longo deste sistema. O trabalho foi baseado em duas etapas: na primeira foi estudada a variabilidade da concentra??o da DBO,
DQO e COT e an?lise das rela??es entre esses par?metros, no afluente, efluente e em ?reas dentro das lagoas. Na segunda etapa foi determinada a constante de biodegrada??o da
mat?ria org?nica k inicialmente ao longo do sistema (afluentes, ?reas e efluentes), utilizando os m?todos matem?ticos dos M?nimos Quadrados e Thomas. Em seguida, k foi avaliado em fun??o do modelo hidrodin?mico determinado atrav?s do n?mero de dispers?o (d), pelos m?todos emp?ricos e pela Avalia??o Parcial Hidrodin?mica (APH), realizada por
meio de tra?agem na lagoa facultativa prim?ria, em uma faixa correspondente a 10 % do comprimento total da lagoa. Na avalia??o dos par?metros analisados, durante o
monitoramento, as concentra??es da mat?ria org?nica biodegrad?vel, medida pela DBO e DQO, foram, gradativamente, reduzidas entre os afluentes e efluentes do sistema, apresentando uma efici?ncia 71,95 % para DBO e de 52,45 % para DQO. Na determina??o da constante cin?tica k, pelos m?todos matem?ticos, considerando o M?todo dos m?nimos quadrados, temos os seguintes valores de k no afluente e efluente das lagoas: facultativa prim?ria (0,23 dia-1 e 0,09 dia-1), matura??o 1 (0,04 dia-1 e 0,03 dia-1) e matura??o 2 (0,03 dia-1 e 0,08 dia-1) e pelo m?todo de Thomas os valores de k no afluente e efluente das
lagoas s?o: facultativa prim?ria (0,17 dia-1 e 0,07 dia-1), matura??o 1 (0,02 dia-1 e 0,01 dia-1) e matura??o 2 (0,01 dia-1 e 0,02 dia-1). Atrav?s da Avalia??o Parcial Hidrodin?mica, na faixa correspondente a 10% do comprimento total da lagoa facultativa prim?ria, pode-se
concluir que, pelo numero de dispers?o encontrado (d = 0,04) o escoamento ? do tipo disperso e a constante cin?tica apresenta um valor de 0,20 dia-1
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