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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.
261

Avaliação da viabilidade do reúso de água para recarga de aquíferos na região metropolitana de São Paulo / Viability evaluation of water reuse to aquifer recharging at São Paulo metropolitan area

Marina Westrupp Alacon Rayis 06 June 2018 (has links)
Região Metropolitana de São Paulo, onde a disponibilidade hídrica foi classificada como \"Crítica\", durante os anos de 2014 e 2015 ocorreu um período de seca que originou a denominada \"crise hídrica\", agravando a situação dos mananciais que abastecem a região. Os estudos sobre mudanças climáticas demonstram não ser um fenômeno isolado e, diante disso, a adoção de tecnologias para reúso de água é essencial para aumentar a disponibilidade hídrica de locais que enfrentam cenários de escassez, como a RMSP. A recarga de aquíferos com efluentes tratados para reúso de água é uma técnica que, se adotada corretamente, pode trazer benefícios como o aumento do volume de água subterrânea disponível para a população. Para estudo da tecnologia, buscou-se como referência as plantas de Shafdan (Israel), Atlantis (África do Sul), Sabadell (Espanha), Adelaide (Austrália), avaliando principalmente os processos de tratamento, métodos de recarga e características qualitativas dos efluentes utilizados para recarga de aquíferos. Foram consultadas as legislações de Estados Unidos e da Espanha sobre o assunto e, com base nestas referências, foram adotados os seguintes requisitos de qualidade do efluente para recarga de aquíferos: sólidos suspensos (35 mg/L), carbono orgânico dissolvido (125,0 mg/L), DBO5,20 (25,0 mg/L), nitrato (25,0 mg/L) e Escherichia coli (1000 UFC/100 mL). A partir dos estudos de caso e das legislações, foi definido que o requisito mínimo de tratamento para recarga é o tratamento terciário para remoção de nitrogênio. Foi avaliada a replicabilidade desta técnica na Região Metropolitana de São Paulo através de comparativos entre os requisitos definidos e as características do efluente e da água de reúso produzida na RMSP em quatro cenários: legislação aplicável ao lançamento de efluentes tratados, características do efluente tratado a nível secundário de uma das ETEs da RMSP, características da água de reúso produzida na RMSP para usos urbanos e características da água de reúso produzida para uso industrial na planta Aquapolo. Verificou-se que atualmente apenas a água de reúso produzida no Aquapolo é submetida a tratamento terciário e atende aos requisitos qualitativos para recarga adotados neste trabalho. O custo de operação de um sistema de produção de água de reúso e recarga de aquíferos foi estimado em US$ 1,41/m³, valor superior à tarifa de água potável comercializada para residências na RMSP, atualmente US$ 0,75/m³. Concluiu-se que há potencial para adoção da tecnologia de recarga de aquíferos com água de reúso na RMSP, visto que há tecnologia disponível para produzir água de reúso na qualidade requerida. Ainda assim, é necessária a avaliação da hidrogeologia local antes de praticar a recarga. Em relação ao custo, o valor da tarifa de água potável vigente é expressivamente menor quando comparado ao valor caso a tecnologia proposta nesse trabalho fosse implantada. Entretanto, deve-se avaliar a importância da adoção de alternativas para disponibilização de água para a população. Ou seja, mesmo que em primeira vista seja mais onerosa, esta técnica é uma oportunidade para obtenção de água para diversos usos em situações de extrema seca, quando o valor da água passa a ser inestimável. / In the São Paulo metropolitan region, where water availability was classified as \"critical\", during the years of 2014 and 2015 there was a period of drought that led to the \"water crisis\", aggravating the situation of the water sources that supply the region. Studies on climate change demonstrate not be an isolated phenomenon and, given this, the adoption of technologies for reuse of water is essential to increase the water availability in areas facing drought situations, like SPMR. The aquifer recharge with treated wastewater to water reuse is a technics that, if properly implemented, can bring benefits as increasing the volume of groundwater available to the population. For the study of the technology, the reference plants were Shafdan (Israel), Atlantis (South Africa), Sabadell (Spain), Adelaide (Australia), survey the treatment processes, recharge methods and qualitative characteristics of effluents to aquifer recharge. The legislation of the United States and Spain was consulted and, based on these references, the following aquifer recharge effluent quality requirements were adopted: suspended solids (35 mg/L), organic solved carbon (125,0 mg/L), BOD5,20 (25,0 mg/L), nitrate (25,0 mg/L) e Escherichia coli (1000 UFC/100 mL). From the case studies and legislation, it was defined that the minimum treatment requirement for recharge is the tertiary treatment for nitrogen removal. The replicability of this technics in the Metropolitan Region of São Paulo was survey through comparisons between the defined requirements and the characteristics of the effluent and the reuse water produced in the RMSP in four scenarios: applicable legislation to treated effluents discharge, effluent characteristics at secondary level treated, reuse water produced in the SPMR for urban uses and characteristics of the reuse water produced for industrial use in Aquapolo. It was verified that currently only the reuse water produced in Aquapolo is subjected to tertiary treatment and meets the qualitative requirements for recharge adopted in this study. The operating cost of a reuse and aquifer recharge water production system was estimated at US$ 1,41 / m³, which is higher than the drinking water tariff traded for residences in the RMSP, currently US$ 0,75 / m³. It was concluded that there is potential for the adoption of recharge water reuse technology in the RMSP, because the technology is available there to produce reuse water in the required quality. Nevertheless, it is necessary to study the local hydrogeology before the recharge. About cost, the value of the current drinking water tariff is significantly lower when compared to the value in case the technology proposed in this work was implemented. However, the importance of adopting alternatives for water availability to the population should be study. That is, even if it is more expensive at first sight, this technique is an opportunity to obtain water for various uses in situations of extreme drought, when the water value becomes inestimable.
262

Reuso de água residuária tratada na irrigação da cultura do pimentão (Capsicum annun L.) / Treated wastewater reuse in the irrigation of pepper culture (Capsicum annun L.)

Anamaria de Sousa Duarte 02 February 2007 (has links)
A reutilização de efluentes domésticos tratados para fins agrícolas pode favorecer o desenvolvimento de uma determinada região, particularmente nos casos de escassez de água. Os benefícios econômicos que o reuso pode proporcionar estão relacionados ao aumento da área cultivada e da produtividade agrícola, decorrente do aporte de nutrientes encontrados nestas águas. O objetivo desta pesquisa foi avaliar os efeitos do reuso de efluente doméstico tratado na irrigação de pimentão, visando produzir frutos adequados para consumo humano, e aumentar o rendimento da cultura em relação ao rendimento obtido usando água potável. Foram avaliadas características físicas, químicas e microbiológicas do efluente tratado, da água potável utilizada e do solo usado no cultivo. Também se avaliou o efeito do elemento nitrogênio fornecido pelo efluente e suas implicações no estado nutricional das plantas, nas medidas de crescimento, na produção de matéria seca e no rendimento da cultura, bem como as características microbiológicas dos frutos produzidos. Esse estudo foi realizado no período de Maio a Setembro de 2005, com uma variedade de pimentão. O delineamento experimental foi aleatorizado em esquema fatorial 4x2, sendo quatro tipos de água e dois níveis de adubação, e 12 repetições para cada tratamento. Foi possível concluir que a água residuária apresentou boas qualidades físicas, químicas e microbiológicas, não alterou significativamente os teores de macro e micronutrientes do solo nem provocou aumento na contaminação microbiológica desse, sendo, portanto, adequada para irrigação da cultura do pimentão. Além disso, o N mineral necessário para as plantas foi suprido parcialmente pela concentração de nitrogênio contido na água residuária usada. Exceto para o fósforo, as plantas cultivadas com água residuária apresentaram teores adequados de macro e micronutrientes no tecido foliar, e, na presença de N mineral, não houve alterações significativas na matéria seca da plantas. Entretanto, na ausência do fertilizante nitrogenado, a água residuária propiciou um incremento significativo dessa variável. O diâmetro de colo das plantas e sua altura foram maiores com o uso de água residuária do que com uso de água potável, além de proporcionar um aumento de 60% no rendimento dos frutos. Os frutos produzidos no experimento foram aceitáveis para o consumo, de acordo com os padrões recomendados pela Resolução n.º 12 de 02/01/2001 da Agência Nacional de Vigilância Sanitária – ANVISA, sendo de qualidade microbiológica superior aos frutos comercializados, principalmente em relação aos coliformes totais. / The use of treated wastewater for agricultural irrigation can improve the development of a particular region, particularly if such region suffers from water scarcity problems. Some of the economic benefits achieved with wastewater reuse are the increase of the cultivated area and agricultural productivity due to the richness of nutrients found at the sewage. However, the reuse of untreated sewage can cause environmental and health problems, which can be avoided if the sewage is used in a safe manner. This work aims to provide an analysis of the effects of treated wastewater reuse in pepper plants, in order to produce fruits for human consumption and to increase plant productivity when compared to potable water irrigation. In this research it was assessed the physical, chemical and microbiological characteristics of the treated effluent, the tap water and the cultivated soil. It was also assessed the effect of the nitrogen element found in wastewater and its implications on the plants nutrition, growth measures, dry matter production and yield crop, as well as the microbiological characteristics of the produced fruits. This research was carried out from May to September 2005 and it was cultivated one variety of pepper. The experimental design was randomized in a 4 x 2 factorial scheme (four water types and two fertilization levels) and twelve repetitions. By the end of the experiment it was possible to conclude that the effluent presented adequate physical, chemical and microbiological quality for pepper plants irrigation, and, in general, did not significantly change the concentration of macronutrients and micronutrients of the cultivated soil, neither the microbiological contamination, which makes it suitable for pepper plants irrigation. Furthermore, the plant nutritional need of N-mineral was partially supplied by the nitrogen concentration found in the effluent used for irrigation. With exception of the phosphorus, all plants presented adequate concentrations of macronutrients and micronutrients on the tissue of the leaf, when irrigated with wastewater, and when using N-fertilizer, no changes were observed in the production of dry matter of the plants. However, when N-fertilizer was absent, there was an increase of this variable when using wastewater irrigation. The height and steam diameter of the plants irrigated with wastewater were bigger than those irrigated with tap water, and the fruit yield increased in almost 60%. The fruits yielded in this research are suited for human consumption according to the resolution No 12 dated 02/11/2001 of the "Agência Nacional de Vigilância Sanitária – ANVISA", and presented presented a better microbiological quality in comparison to the commercially available fruits, primarily due to the total coliforms.
263

Caracterização microbiológica, parasitológica e físico-química da água de lavagem de filtros recirculada em ETA de ciclo completo = Microbiological, parasitological and physico-chemical characterization of filter backwash water recirculated in full cycle WTP / Microbiological, parasitological and physico-chemical characterization of filter backwash water recirculated in full cycle WTP

Canale, Ivan, 1977- 11 April 2014 (has links)
Orientador: Cassiana Maria Reganhan-Coneglian / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-26T04:53:56Z (GMT). No. of bitstreams: 1 Canale_Ivan_M.pdf: 7288933 bytes, checksum: 93678fbce9055e79b05000fd1cab8c23 (MD5) Previous issue date: 2014 / Resumo: Estações de Tratamento de Água (ETA) de ciclo completo. Como o volume de ALF pode representar de 3 a 6% do volume de água tratada produzido na ETA, existe interesse cada vez maior no tratamento desse efluente para fins de recirculação junto com a água bruta aduzida à ETA. Entretanto, existe uma preocupação de que essa água residuária possa conter matéria orgânica, sólidos totais, metais, carbono orgânico, precursores de trihalometanos, cistos/oocistos de protozoários ou outras impurezas concentradas durante o processo de filtração. Este trabalho de pesquisa tem como objetivo caracterizar com base em parâmetros físico-químicos, microbiológicos e parasitológicos a água de lavagem de filtros gerada e recirculada na ETA Capim Fino, em Piracicaba / SP - Brasil. Foram avaliadas 12 amostras da água bruta do manancial que abastece a ETA (rio Corumbataí), ALF bruta, ALF clarificada (com o uso de polímeros auxiliares ou por simples sedimentação) e água filtrada da ETA. Para caracterização da ALF foram analisados os parâmetros físico-químicos: cloro residual, cor, turbidez, pH, alumínio solúvel, sólidos totais fixos, sólidos totais voláteis, sólidos sedimentáveis, carbono orgânico total e o potencial de formação de trihalometanos; os parâmetros microbiológicos: coliformes totais, Escherichia coli; e os protozoários patogênicos: Giardia spp. e Cryptosporidium spp. O monitoramento da ALF bruta apontou como principais características físico-químicas deste efluente elevados teores de turbidez, alumínio, carbono orgânico total, sólidos totais (fixos e voláteis), sólidos sedimentáveis e potencial de formação de THM. A clarificação da ALF com polímero aniônico possibilitou a redução na concentração dos diversos constituintes analisados. Giardia spp. foi detectada na água bruta (cinco resultados positivos e concentração de cistos variando de <LMD a 75,0 cistos/litro) e na ALF clarificada (dois resultados positivos e concentração de 50 cistos/litro). A pré-cloração realizada na ETA, bem como o uso de água tratada (clorada) para lavagem dos filtros garantiu praticamente ausência de E. coli na água de lavagem. A avaliação da água filtrada da ETA apresentou resultados em conformidade com a Portaria 2914/2011 (padrão de potabilidade) do Ministério da Saúde, com exceção da turbidez, onde foram observados quatro resultados acima do limite de 0,5 NTU estabelecido pela Portaria (1,53, 0,54 , 0,59 e 0,74 NTU), o que pode indicar um transpasse de partículas no efluente filtrado nos primeiros minutos seguintes à lavagem dos filtros. Não foram detectados E. coli ou protozoários na água filtrada. Diante do fato que a recirculação da ALF clarificada junto com a água bruta está ocorrendo numa vazão de 60 L/s, que corresponde a 4,5% da vazão de água bruta (1300 L/s) e de forma intermitente, provavelmente não deverão ocorrer efeitos indesejáveis ao processo de tratamento ou o comprometimento da qualidade da água tratada. Com intuito de precaução, é importante que seja dada toda a atenção ao tratamento (clarificação) da ALF antes da recirculação, para redução da turbidez a níveis mínimos possíveis e que a recirculação do efluente clarificado seja realizada na vazão de 4,5% ou menor / Abstract: Filter backwash water (FBWW) is the largest liquid waste generated in a conventional water treatment plant (WTP). As the volume of FBWW can represent from 3 to 6% of the volume of treated water produced in the WTP, there is an increasing interest in treatment and recycling of this effluent with raw water adducted to WTP. But FBWW would contain concentrated organic matter, total solids, metals, organic carbon, trihalomethanes (THM) precursors, cysts/oocysts of protozoa and other impurities which could be a concern. This research aims to characterize FBWW generated and recirculated in Capim Fino WTP in Piracicaba / SP - Brazil by physico-chemical, microbiological and parasitological analyses. Twelve samples of raw water from the river that supplies the WTP (Corumbataí river), raw FBWW, clarified FBWW (using auxiliary polymers or simple sedimentation) and filtered water were collected and evaluated. The physico-chemical parameters were: residual chlorine, color, turbidity, pH, soluble aluminum, total fixed and volatile solids, settleable solids, total organic carbon and THM potential formation; microbiological parameters: total coliforms and Escherichia coli; and pathogenic protozoa Giardia spp. and Cryptosporidium spp. Monitoring the raw FBWW pointed as the main physicochemical characteristics high levels of turbidity, aluminum, total organic carbon, total solids (fixed and volatile), sedimentary solids and THM potential formation. Clarification of FBWW with anionic polymer resulted in a reduction in the concentration of the various parameters. Giardia spp. was found in raw water (five positive results and cyst concentration ranging from <Minimum Detection Limit to 75 cysts/liter) and in clarified FBWW (two positive results, concentration of 50 cysts/liter). The pre-chlorination performed in the WTP and the use of treated water (chlorinated) for washing the filters virtually assured absence of E. coli in the FBWW. The filtered water were in compliance with the Brazilian drinking water standards, with the exception of turbidity. Four samples were above the maximum limit of 0.5 NTU (1.53, 0.54, 0.59 and 0.74 NTU), which may indicate a passage of particles in the first minutes after the washing of the filters. E. coli and protozoa were not detected in the filtered water. Because of the recirculation of clarified FBWW is mixed with raw water at a flow of 60 L/s, which corresponds to 4.5% of the flow of raw water (1300 L/s) and intermittently, it is probable that no undesirable effects would occur in the treatment and in the quality of the drinking water. It is important that full attention is given to treatment (clarification) of FBWW before recirculation to reduce turbidity to the minimum levels that are possible and that the recirculation of clarified effluent is conducted at a flow rate of 4.5% or less / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
264

Usos da água na indústria sucroalcooleira = estudo de caso / Water uses in the sugar and ethanol industry : a case study

Ribeiro, Fabíola Maria Gonçalves 19 August 2018 (has links)
Orientador: Carlos Gomes da Nave Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-19T19:25:17Z (GMT). No. of bitstreams: 1 Ribeiro_FabiolaMariaGoncalves_M.pdf: 4448670 bytes, checksum: 4f3fe46bb1701ffda93bc20a87a024fa (MD5) Previous issue date: 2011 / Resumo: A história do homem na Terra tem como marca principal a alteração do equilíbrio dinâmico dos ecossistemas, resultando num processo crescente de degradação ambiental. O uso da água, demandada para o desenvolvimento das diferentes atividades que garantem a produtividade econômica e o bem estar social, acarretou num consumo cada vez maior desse recurso natural como se fosse abundante e infinito. A escassez de recursos hídricos é uma realidade, inclusive no Brasil, tornando-se necessário desenvolver estratégias para o adequado gerenciamento desse recurso. Nesse contexto, o uso racional da água deve ser estimulado, tendo no reuso e reciclagem formas de mitigar a captação e consumo de água, favorecendo o aumento da oferta e contribuindo para a sustentabilidade. A indústria sucroalcooleira se caracteriza pelo uso intensivo de água, verificando-se nas usinas de açúcar, com destilaria anexa, um uso médio da ordem de 22 m³/t cana total. Esse valor não reflete os volumes captados ou consumidos, uma vez que o setor vem adotando práticas de gestão ambiental e de recursos hídricos, com ênfase ao reuso da água. O objetivo deste trabalho foi identificar os usos da água em duas unidades de produção de açúcar e etanol, localizadas na UGRHI 10, com distintas disponibilidades hídricas nos trechos dos rios onde se encontram instaladas e, o quanto a prática do reúso alterará a captação, lançamento e consumo de água, avaliando os consequentes valores a serem pagos pela cobrança pelo uso desse recurso natural. Como resultado principal teve-se que, na Unidade I, com o fechamento do circuito de água da fabricação de açúcar, ocorrido em 2009, o uso médio de água sofreu uma redução de 43%, ou seja, de 23 m³/t cana total para 13,2 m³/t cana total. Na Unidade II, onde a prática do reúso é melhor consolidada, o uso médio foi de 4,5 m³/t cana total. Nessa Unidade, com a adoção da limpeza a seco, ocorreu uma redução de 75% no volume de água utilizado nessa etapa. Verificou-se ainda que a prática do reúso de água no processo produtivo permitiu um abatimento significativo nos valores pagos pela cobrança pelo uso da água. Na Unidade I essa redução foi de 55 %, enquanto que na Unidade II foi de 86 %. Com os resultados obtidos apontam-se ganhos ambientais e financeiros associados às práticas de uso racional da água / Abstract: The history of the man on Earth is marked by the alteration of the ecosystems dynamic equilibrium, resulting in an increasing of environmental degradation process. The water use, demanded for the development of different activities to ensure economic productivity and social welfare, has led to a growing consumption of that natural resource as if it were abundant and infinite. Scarcity of water resources is a reality, also in Brazil, becoming necessary to develop strategies for proper management of this resource. In this context, the rational use of the water must be encouraged, having in the reuse and recycling ways to mitigate the collection and consumption of water, favoring the increase of supply and contributing to the sustainability. The sugar and ethanol industry is characterized by intensive water use, checking on sugar plants with attached distillery an average use of about 22 m³/t total sugarcane. This value does not reflect the collected or consumed volumes, since the sector has been adopting environmental and water resources management practices, with emphasis on the water reuse. The aim in this study was to identify water uses in two plants manufacturing of sugar and ethanol, installed in Water Resources Management Unit 10, with distinct water availability in the stretches of rivers where they are installed and, how the practice of reuse of water will change the collection, discharge and consumption of water, evaluating the resulting values to be paid by charging for the use of this natural resource. As main result was that in Unit I, with the closing of the water circuit of sugar manufacturing, which occurred in 2009, the average water use was reduced by 43%, i.e., from 23 m³/t total sugarcane, to 13,2 m³/t total sugarcane. In Unit II, where the reuse practice is better consolidated, the average use was 4,5 m³/t total sugarcane. In this Unit, with adoption of dry cleaning, occurred a reduction of 75% in volume of water used in this step. It was also verified that the practice of water reuse in the productive process allows a significant reduction on the amount of water charging. In Unit I, this reduction was 55%, while in Unit II it was 86%. With the results obtained point to environmental and financial gains associated with water rational use practices / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
265

Avaliação da toxicidade de efluente sanitário tratado e condicionado para aplicação na agricultura, utilizando Allium cepa, Daphnia similis e Vibrio fischeri, como organismos-teste / Toxicity assessment of treated sanitary effluent for application in agriculture, using Allium cepa, Vibrio fischeri and Daphnia similis as test organisms

Torres, Danila de Leone França e Freitas 21 August 2018 (has links)
Orientador: Alexandre Nunes Ponezi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-21T07:25:38Z (GMT). No. of bitstreams: 1 Torres_DaniladeLeoneFrancaeFreitas_M.pdf: 2036503 bytes, checksum: 068ab775d9c675592e34d0bfdd2ca1e9 (MD5) Previous issue date: 2012 / Resumo: O uso de efluente tratado na agricultura irrigada constitui uma alternativa adequada para a preservação de mananciais, além de ser uma importante fonte de nutrientes. No entanto, os riscos de toxicidade devem ser avaliados. Testes ecotoxicológicos apresentam-se como uma ferramenta apropriada, devido à sensibilidade dos organismos e sua ampla aceitação por órgãos governamentais e científicos. O objetivo do presente estudo foi avaliar a toxicidade aguda na fotobactéria marinha Vibrio fischeri e no microcrustáceo Daphnia similis (CE50) e do potencial citotóxico, genotóxico e mutagênico em Allium cepa (cebola) de um efluente sanitário tratado usado para irrigação. Os ensaios foram realizados no efluente bruto e nos tratados utilizados para irrigação: anaeróbio e pos-tratamento anaeróbio (nitrificado). Os resultados evidenciaram que o efluente bruto, apresentou uma maior variação dos valores de CE50 para ambos os organismos. O efluente anaeróbio apresentou um efeito tóxico agudo maior para V. fischeri que para D. similis. Já o nitrificado (pos-tratamento anaeróbio) apresentou uma toxicidade aguda menor para ambos os organismos testados. Na avaliação das aberrações cromossômicas em A. cepa, os efluentes tratados apresentaram uma redução do potencial citotóxico (p<0,05) em relação ao efluente bruto. Pode-se concluir que os testes escolhidos foram adequados para o monitoramento do efluente. Recomenda-se que o uso de efluente tratado na agricultura seja realizado de forma regrada, atentando para os padrões de Boas Práticas Agrícolas (GAP) e de toxicidade. Além disso, em escala real é necessário um estudo de monitoramento periódico que avalie impactos a longo prazo, incluindo testes de toxicidade crônica / Abstract: The use of the treated effluent in agriculture has proven to be an important alternative, since its preservation of water and its potential as source of nutrients, with low potential for negative impact on the environment. However, toxicity remains an important issue. Ecotoxicological tests are appropriate tools to evaluate the toxicity of effluents. The aim of this study was to evaluate acute toxicity on marine bacteria Vibrio fischeri, on micro crustacean Daphnia similis (EC50) and on Allium cepa (onion) (assessment of cytotoxic, mutagenic and genotoxic potencial) in treated sanitary effluent used for irrigation. We tested the raw effluent, and in its treatments, used for irrigation: anaerobic and anaerobic posttreatment (nitrified). Our results showed that the raw effluent had a greater variation of EC50 for both organisms, due to an intrinsic variability of its composition. The anaerobic effluent had a greater acute toxic effect on V. fischeri than for D. similis. Yet, the nitrified (anaerobic post-treatment stage) showed a lower toxicity for both tested organisms. We found a reduction in the citotoxical potential in A. cepa as compared to the raw efluente. We concluded that the tests chosen were adequate for monitoring the effluent since the organisms showed adequate sensitivity. It is therefore suggested that the use of treated wastewater in agriculture should be standardized, noting Good Agricultural Practices (GAP) and toxicity stardards. Furthermore for larger scale assumption it is necessary a periodic monitoring study to assess long term impacts, including chronic toxicity tests / Mestrado / Saneamento e Ambiente / Mestra em Engenharia Civil
266

Uso de água e análise exergética na produção integrada de etanol de primeira e segunda geração a partir da cana-de-açúcar / Water use and exergetic analysis in the integrated production of first and second generation ethanol from sugarcane

Mosqueira Salazar, Klever Joao 20 August 2018 (has links)
Orientadores: Silvia Azucena Nebra de Pérez, Joaquim Eugênio Abel Seabra / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T18:24:46Z (GMT). No. of bitstreams: 1 MosqueiraSalazar_KleverJoao_M.pdf: 3838720 bytes, checksum: c2f6132a9e3da195a47d32604b8252c3 (MD5) Previous issue date: 2012 / Resumo: A produção e o consumo de biocombustíveis têm aumentado rapidamente nos últimos anos, no entanto, esse crescimento tem levantado questões a respeito da sua sustentabilidade. Uma nova configuração da produção de biocombustíveis, chamados de segunda geração, a partir principalmente de resíduos agroindustriais como o bagaço de cana-de-açúcar, se apresenta como uma solução frente àquelas questões, ao aumentar a produção com o mesmo volume de recursos. Não obstante, a sua sustentabilidade no que diz respeito ao uso da água ainda precisa ser comprovada, devido a que o consumo de água na fase industrial é considerado um ponto crítico decorrente do seu aumento durante o processo de hidrólise, ao se desenvolver este em soluções com baixas concentrações de sólidos. Assim, este estudo objetiva a avaliação de alguns aspectos da sustentabilidade da produção integrada de etanol de primeira e segunda geração a partir da cana-de-açúcar para diferentes cenários, comparada ao processo convencional, através do impacto no consumo de água por litro de combustível produzido, e mediante uma análise exergética do processo visando determinar a influência deste processo nos custos exergéticos dos produtos da planta. Foi realizado um inventário dos consumos de água por cada processo durante a produção de etanol, e identificou-se ainda o potencial de reúso dos efluentes visando a redução da captação externa de água. Os resultados revelaram que mesmo com a introdução do novo processo, através de adequadas medidas de reúso como o fechamento de circuitos de água, e o tratamento dos novos efluentes na produção integrada, produzindo inclusive biogás, é possível atingir patamares de captação de água muito próximos aos já existentes no atual setor sucroalcooleiro. Por outro lado, desde a visão da termodinâmica, quando considerados como produtos o etanol anidro e a eletricidade excedente no processo convencional, foi alcançada uma eficiência de segunda lei igual a 28%, enquanto no processo integrado, considerando ademais ao biogás como produto, foram atingidos maiores desempenhos na gestão dos recursos com valores na faixa de 35 a 37% devido ao aumento da produção de etanol e eletricidade excedente. Adicionalmente, foram encontrados aumentos entre 13,5% e 10,2% nos custos exergéticos do etanol anidro durante a produção integrada, decorrente principalmente das maiores irreversibilidades geradas na caldeira com o aumento da produção de vapor / Abstract: Production and consumption of biofuels have been growing rapidly in the last few years; however, this rapid growth has raised questions regarding its sustainability. A new configuration of biofuel production, the so called second generation biofuels, mainly produced from agroindustrial residues such as sugarcane bagasse, appears as a solution to those issues, increasing production with the same amount of resources. Nevertheless, its sustainability relative to water use has still to be proven; because of water use in industrial stage is considered critical, due to its increase during the hydrolysis process, which occurs in solutions with low concentrations of solids. Thus, this study aims the assessment of some sustainability topics of the integrated production of first and second generation ethanol from sugarcane compared to the conventional process, through the impact on consumption of water per liter of fuel produced, and by an exergy analysis of the process to determine its influence in the exergetic cost of the main plant's products. It was perfomed an inventory of water consumption by each process during ethanol production and it was even identified the potential of effluents for recycling in order to reduce water withdrawal. Results showed that considering the introduction of the new process, and through appropriate procedures of reuse, such as closing water circuits and treatments of new effluents from integrated production, producing even biogas, it is possible to achieve water withdrawals close enough to those existing in current ethanol plants. Moreover, from the thermodynamic point of view, considering ethanol and surplus electricity as the major products in the conventional process, it was obtained a second law efficiency equal to 28%, while in the integrated process, when considering biogas also as a product, it was reached a greater performance in resources management with values in the range of 35 to 37% owing to the larger ethanol and surplus electricity production. Additionally, increases between 13,5 and 10,2% in the exergetic costs of anhydrous ethanol in the integrated production were found mainly due to irreversibilities generated in the boiler for steam production / Mestrado / Planejamento de Sistemas Energeticos / Mestre em Planejamento de Sistemas Energéticos
267

Optimising the use of small-scale greywater treatment plants in South Africa

Natha, Shaym 26 June 2015 (has links)
M.Ing. (Civil Engineering) / To relieve the extreme pressure placed on overburdened water and wastewater infrastructure, the reuse of light wastewater was identified as a possible source of water supply for non-potable applications. The light wastewater discharge intercepted on-site can be recycled, treated and thereafter distributed to fixtures for agricultural, sanitation and gardening based activities. Sources for this light wastewater stream includes bathroom showers, bath tubs, hand wash basins including that of kitchens, laundry and washing machine outflows of recyclable quality. This type of re-usable water is called greywater (GW). This on-site re-use concept has potential to offer greater potable water savings if correctly implemented. For the purpose of this research, this particular type of waste stream excluding the kitchen and laundry discharge was the water source considered for the supply to this greywater treatment plant (GWTP). In 2009, the Water Research Commission (WRC) funded a greywater pilot study in a joint venture between the University of Witwatersrand (WITS) and the University of Johannesburg (UJ). Over the last few years, this project had progressed with new outcomes each year. The pilot GWTP at Unit 51, Student Town, UJ in Auckland Park was used for the purpose of this study. The selected reuse application for the GW effluent was for toilet flushing. GW was supplied to two toilets in a residential student complex housing 16 female and male students i.e. 8 students on each floor. The highlights of the WRC study included: a lack of satisfactory treatment efficiency and a well-defined protocol to address the problems associated with the slightly poor quality of effluent produced (i.e. unpleasant odours, greyish appearance and the unacceptable microbial count). Determining and addressing the user perceptions and user education about GW usage, respectfully, was a significant component in the successful management of the project. In this report, a practical evaluation of three crucial components of the GWTP was completed. These three components viz. treatment efficiency, user perceptions and quality standards, were common aspects of concern for existing decentralised GWTP’s within residential or small commercial stands.
268

Modeling the Extent of Virus Removal in Waste Stabilization Ponds to Support Reuse of Wastewater

Vannoy, Kelly James 17 March 2016 (has links)
Waste stabilization ponds (WSPs) are one of the most prevalent types of domestic wastewater treatment technologies employed worldwide, and global stressors such as urbanization, population growth, climate change, and water scarcity have increased the demand for reusing treated wastewater. The safe reuse of treated wastewater in agriculture can ease water scarcity, aid in food production, and reduce environmental degradation from the discharge of wastewater effluent to surface waters. The ability to predict virus concentrations in wastewater effluent is an important criterion for determining whether wastewater is suitable for discharge to the environment or for reuse in agriculture. However, many uncertainties remain about virus removal efficiency in WSPs and there is currently no mechanistic or empirical model that reliably predicts virus removal in WSPs. The overall objective of this thesis research was to model the extent of virus removal in individual waste stabilization ponds to support the reuse of wastewater. A literature review was used to create a database of estimated apparent virus removal rate coefficients (Kv,app) in three different WSP types (anaerobic, facultative, and maturation ponds). The database consisted of 249 paired influent and effluent concentrations of enteric viruses or bacteriophages from 44 unique WSP systems, comprised of 112 individual WSPs from 19 different countries. Apparent virus removal rate coefficients (Kv,app) were calculated for each individual WSP using the following three mathematical models from reactor theory: complete mix, plug flow, and dispersed flow. Pearson’s correlation analysis was used to determine correlations between Kv,app values and the following design, operational, and environmental parameters: solar radiation, air temperature, pond depth, hydraulic retention time (HRT), and virus loading rates. The median Kv,app values were greater for anaerobic ponds than for facultative and maturation ponds; however, Kv,app values in facultative and maturation ponds had more significant correlations with design, operational, and environmental parameters. Additionally, Kv,app values appear to be significantly different for various types of enteric viruses and bacteriophages. Alternative multiple linear regression equations were developed to predict Kv,app values using the design, operational, and environmental parameters as explanatory variables. Analysis of variance (ANOVA) tests were used to select the most appropriate multiple linear regression equations with the least amount of explanatory variables. The most appropriate plug flow and dispersed flow multiple linear regression equations for predicting Kv,app values included air temperature and HRT as explanatory variables. The results indicate that the plug flow regression equation was able to better predict Kv,app values (R2 = 0.38) than the dispersed flow regression equation (R2 = 0.24) in facultative and maturation ponds based on the dataset. However, both the dispersed flow and plug flow models had R2 values of approximately 0.84 when they were used to predict effluent virus concentrations in facultative and maturation ponds based on the dataset. According to this research, the plug flow regression equation is recommended for predicting apparent virus removal rate coefficients in WSPs. However, a multi-model approach that utilizes both the plug flow and dispersed flow models may yield a more robust mathematical model that can improve WSP design, reliably predict virus removal in WSPs, and ultimately be used to support wastewater reuse.
269

Water demand management : a case study of the Kingdom of Bahrain

Al-Maskati, Hana January 2011 (has links)
This research used an Integrated Water Resource Management approach to investigate how Water Demand Management (WDM) measures at government, utility and end-user levels could contribute to providing sustainable water supply to Bahrain, which is in an arid to semiarid region. The main driver for this research was the supply-driven orientation favoured by policy makers and practitioners in Bahrain with little consideration for demand management. This leads to a high estimated gross per capita consumption 525 l/c/d as of 2010. There was also a need to investigate the institutional environment for managing water resources and delivering sustainable water supply to Bahrain. The research adopted a case study methodology which included qualitative analysis of interviews and documents from the water authority, and quantitative analysis of questionnaire surveys and pilot studies. The research adopted a cross-sectional approach to the analysis of activities associated with WDM practice in Bahrain. All findings and conclusions were evaluated/validated using surveys distributed to water experts and customers. Based on their feedback, findings and conclusions were revised. The main finding of this research was that the tariff is highly subsidized by the government and there is no encouragement for water savings. The low tariff leads to low revenue which in turn affects the budget allocated to the relevant departments and units at the Electricity and Water Authority (EWA). This impacts negatively on their activities. It was found that there is no effective strategy for integrated water resources management; there is a high level of Non Revenue Water (NRW) (38%); and limited reuse of grey water and water use saving devices. In addition there is a lack of public awareness and understanding of the benefits of WDM among all levels of society including professionals and water supply providers. The research concluded that improving water use efficiency in Bahrain should be a priority due to the current high water supply costs. There is a need for proper legislation that enforces the use of WDM; establishment of a national WDM committee with the Water Resources Directorate, and for water resource professionals to follow WDM oriented policies. The research proposed six areas to be further investigated to achieve more efficient use of water: (a) Water tariff reform to recover full water supply costs; (b) institutional reform through activating and enforcing Water Resources Council roles; (c) promoting public awareness about WDM and its benefits; (d) reducing non revenue water; (e) applying positive economic sliding scale incentives for customers who reduce their water consumption.
270

Impact of Sludge Layer Geometry on the Hydraulic Performance of a Waste Stabilization Pond

Ouedraogo, Faissal Romaric 28 June 2016 (has links)
Improving the hydraulic performance of waste stabilization ponds (WSPs) is an important management strategy to not only ensure protection of public health and the environment, but also to maximize the potential reuse of valuable resources found in the treated effluent. To reuse effluent from WSPs, a better understanding of the factors that impact the hydraulic performance of the system is needed. One major factor determining the hydraulic performance of a WSP is sludge accumulation, which alters the volume of the pond. In this study, computational fluid dynamics (CFD) analysis was applied to investigate the impact of sludge layer geometry on hydraulic performance of a facultative pond, typically used in many small communities throughout the developing world. Four waste stabilization pond cases with different sludge volumes and distributions were investigated. Results indicate that sludge distribution and volume have a significant impact on wastewater treatment efficiency and capacity. Although treatment capacity is reduced with accumulation of sludge, the latter may induce a baffling effect which causes the flow to behave closer to that of plug flow reactor and thus increase treatment efficiency. In addition to sludge accumulation and distribution, the impact of water surface level is also investigated through two additional cases. Findings show that an increase in water level while keeping a constant flow rate can result in a significant decrease in the hydraulic performance by reducing the sludge baffling effect, suggesting a careful monitoring of sludge accumulation and water surface level in WSP systems.

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