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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.
31

The bio-disposal of lignocellulose substances with activated sludge

Qi, Bing Cui 03 1900 (has links)
Thesis (PhD)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Lignocellulose is the principal form of biomass in the biosphere and therefore the predominant renewable source in the environment. However, owing to the chemical and structural complexity of lignocellulose substrates, the effective and sustainable utilization of lignocellulose wastes is limited. Many environments where lignocellulose residues are ordinarily stored can be highly acidic (e.g. landfills), and under these circumstances biodegradation of the lignocellulose is slow and unhygienic. Owing to the metabolic activities of the micro-organisms, the initially acidified habitats rapidly undergoes self-neutralization. A number of pathogenic bacteria (coliforms and Salmonella sp.) are present during this slow degradation process and it is therefore imperative to improve the efficiency and hygienic effects of the biodegradation of the lignocellulose. Although the fundamentals of biodegradation of lignocellulose have been widely investigated, many issues still need to be resolved in order to develop commercially viable technology for the exploitation of these waste products. For example, owing to the complex, heterogeneous structure of lignocellulose, the degree of solubilization, modification and conversion of the different components are not clear. Likewise, the overall anaerobic degradation of lignocellulose is not understood well as yet. In this study, the emphasis was on the promotion of solid anaerobic digestion of lignocellulose wastes for environmental beneficiation and waste reutilization. The degradation of lignocellulose in landfill environments was first simulated experimentally. Once the microbial populations and the degradation products of the system were characterized, the promotion of anaerobic digestion by use of activated sludge was studied. This included acidogenic fermentation, as well as recovery of the methanogenic phase. Moreover, special attention was given to the further disposal of humic acids or humic acid bearing leachates formed in the digestive system, since these acids pose a major problem in the digestion of the lingocellulose. With ultrasonication, approximately 50% of the lower molecular weight fraction of humic acids could be decomposed into volatile forms, but the higher molecular weight fraction tended to aggregate into a colloidal form, which could only be removed from the system by making use of ultrasonically assisted adsorption on preformed aluminium hydroxide floes. This was followed by an investigation of the microbial degradation of humic acids and the toxicity of these acids to anaerobic consortia. Further experimental work was conducted to optimize the biological and abiological treatment of lignocellulose in an upflow anaerobic sludge blanket (DASB) reactor fed with glucose substrate. The humic acids could be partially hydrolysed and decomposed by the acid fermentative consortia of the granules in the DASB reactor. Finally, solid mesothermophilic lignocellulose anaerobic digestive sludge can be viewed as a humus-rich hygienic product that can improve the fertility and water-holding capacity of agricultural soil, nourish plants and immobilize heavy metals in the environment as a bioabsorbent. / AFRIKAANSE OPSOMMING: Lignosellulose is die hoofbron van biomassa in die biosfeer en is daarom ook die belangrikste hernubare bron in die omgewing. As gevolg van die chemiese en strukturele kompleksiteit van lignosellulose substrate, is die doeltreffende en volhoubare benutting van lignosellulose afval egter beperk. Die suurgehalte van die omgewings waar lignosellulose reste gewoonlik gestoor word, soos opvullingsterreine, kan hoog wees en onder hierdie omstandighede is die biodegradasie van die lignosellulose stadig en onhigiënies. As gevolg van die metaboliese aktiwiteite van die mikro-organismes ondergaan die aanvanklik aangesuurde habitatte vinnig self-neutralisasie. 'n Aantal patogeniese bakterieë (koliforme en Salmonella sp.) is deurgaans gedurende dié stadige natuurlike proses teenwoordig en dit is dus van die grootste belang om die effektiwiteit en die higiëne van die bioafbreking van die lignosellulose-substraat te verhoog. Alhoewel die grondbeginsels van die bioafbreking van lignosellulose reeds wyd ondersoek is, moet verskeie probleme nog opgelos word ten einde kommersieel haalbare tegnologie te ontwikkel vir die ontginning van afvalprodukte. Byvoorbeeld, as gevolg van die komplekse, heterogene struktuur van lignosellulose, is die graad van solubilisering en die modifikasie en omskakeling van verskillende komponente nog onduidelik. Net so word die algehele anaerobiese afbreking van lignosellulose ook nog nie ten volle verstaan nie. In hierdie ondersoek het die klem geval op die bevordering van soliede anaerobiese digestie van lignosellulose afval vir omgewingsverbetering en die benutting van die afval. Die afbreking van lignosellulose in opvullingsterreine is eers eksperimenteel gesimuleer. Nadat die mikrobiese populasies en die afbrekingsprodukte gekarakteriseer is, is die bevordering van anaerobiese digestie deur die gebruik van geaktiveerde slyk bestudeer. Dit het asidogeniese fermentasie ingesluit, sowel as herwinning van die metanogeniese fase. Spesiale aandag is gegee aan die verdere verwerking van humus sure en humussuurbevattende legate wat in die digestiewe stelsel gegenereer is, aangesien die sure probleme veroorsaak het met die vertering van die lignosellulose. Met ultrasoniese straling is nagenoeg 50% van die lae-molekulêre massafraksie van die humussure ontbind in vlugtige vorm, maar die hoë-molekulêre massafraksie het geneig om in 'n kolloïdale vorm te aggregeer, wat slegs uit die stelsel verwyder kon word deur middel van ultrasonies ondersteunde adsorpsie op voorafgevormde aluminiumhidroksiedvlokkies. Dit is gevolg deur 'n ondersoek na die mikrobiese afbreking van humus sure en die toksisiteit van die sure ten opsigte van anaerobiese konsortia. Verdere eksperimentele werk is gedoen ten opsigte van die biologiese en abiologiese behandeling van lignosellulose in 'n opwaartsvloeiende anaerobiese slikkombersreaktor (OASK) gevoer met glukosesubstrate. Die humus sure kon gedeeltelik gehidroliseer en ontbind word deur die suurgistende konsortia van die granules in die OASK reactor. Ten slotte kan die vaste termofiliese-mesofiliese anaerobiese lignosellulose verteringslik ook gesien word as 'n humusryke higiëniese produk wat die vrugbaarheid en die waterhoudende vermoë van landbougrond kan verhoog, plante kan voed en kan funksioneer as bioabsorbeerder van swaarmetale in die omgewing.
32

Measuring laminar burning velocities

Marshall, Stephen P. January 2010 (has links)
The laminar burning velocity of a fuel is the rate of normal propagation of a 1D flame front relative to the movement of the unburned gas. This is a fundamental property of a fuel that affects many aspects of its combustion behaviour. Experimental values are required to validate kinetic simulations, and also to provide input for models of flashback, minimum ignition energy and turbulent combustion. Burning velocity affects burn duration and consequently power output in spark ignition engines. Burning velocities are affected by pressure, temperature, equivalence ratio, residuals, additives, and stretch rates. The constant volume vessel has been used as it is considered both the most versatile and accurate method of measuring laminar burning velocities. An existing combustion vessel and oven were refurbished and new systems built for fuel injection, ignition, experiment control, data acquisition and high speed schlieren photography. An existing multi-zone model was used to allow calculation of burning velocity from pressure and schlieren data, allowing the user to select data uncorrupted by heat transfer or cellularity. A twelve term correlation for burning velocity was validated using methane modelling data. The chosen data from all the experiments was then fitted to the correlation. Methane, n-butane, n-heptane, iso-octane, toluene, ethylbenzene and ethanol were tested over a wide range of initial pressures (0.5, 1, 2 and 4 barA), temperatures (289-450 K) and equivalence ratios (0.7-1.4). For liquid fuels, tests with real residuals at mole fractions of up to 0.3 were also conducted. Stoichiometric mixture tests were performed at two initial temperatures (380 and 450 K) and the same four initial pressures. For mixtures of iso-octane and ethylbenzene, percentage volumes of 12.5, 25, 50 and 75% iso-octane were tested. It was found that the the percentage of iso-octane affected burning velocity non-linearly. For iso-octane/ethanol, a single 50:50% mixture was tested.
33

Statistické modely pro kapitálové modely pojišťoven / Statistical models for capital models of insurance companies

Švagerková, Lýdia January 2011 (has links)
This work deals with the topic of lapse rate modelling in the field of Life Insurance. First, the theoretical apparatus is established: the linear models and their extension, generalized linear models. Furthermore, we describe the process of model selection and evaluation. In the second part of this work we describe the influence of various individual as well as macroeconomical parameters on the lapse rate. We summarize the findings of previous works in this field. The last part introduces models in statistical software R based on generalized linear models and describes the process of their selection and evaluation. Outputs from these models are interpreted and compared to the ratio analysis results.
34

Fytoextrakce benzodiazepinů z vodných roztoků / Phytoextraction of Benzodiazepines from Water Solutions

Grasserová, Alena January 2019 (has links)
Abstract, key words The aim of this thesis was to perform a phytoextraction experiment with benzodiazepines chlordiazepoxide, diazepam, alprazolam and bromazepam on corn plant (Zea mays). After 14 days of growing of sterile cultivation, new medium (Murashige and Skoog) contaminated with benzodiazepine was added. The starting concentration of benzodiazepine was 10 mg · l-1. After every 24 hours, a sample of medium was collected. The actual concentration of benzodiazepine was measured on HPLC with UV detection. Extractable residues were also analysed to find out whether the benzodiazepine is being translocated to the upper parts of the plant. The same HPLC conditions were used for these samples. The greatest phytoextraction efficiency (the amount of drug extracted by 1 gram of biomass in 24 hours) was observed for chlordiazepoxide, followed by bromazepam, alprazolam and diazepam respectively. The extractable residues analysis confirmed the translocation to the upper parts of the plant for every of the benzodiazepines tested. That indicates a threat for the animals through the food chain contamination. Key words: phytoremediation, phytoextraction, benzodiazepines, extractable residuals, HPLC.
35

Problemática dos metais e sólidos no tratamento de água (estação convencional de ciclo completo) e nos resíduos gerados / not available

Barroso, Marcelo Melo 29 April 2002 (has links)
O aumento da demanda de água potável e por conseqüência dos resíduos gerados, tem levado a indústria da água no Brasil, composto por aproximadamente 7500 ETAs, a deparar-se com dispendiosos ônus técnicos e financeiros no gerenciamento destes resíduos. Os sólidos, e, inclusive metais são os principais constituintes dos resíduos gerados durante o tratamento de água, sejam nos decantadores ou filtros. A compreensão da produção dos metais e sólidos em um ETA, assume grande importância. Apresenta-se neste estudo, os aspectos que envolvem a presença de metais e sólidos no tratamento de água. Realizou-se a avaliação dos metais nas diferentes etapas do tratamento de água. Realizou-se a avaliação dos metais nas diferentes etapas do tratamento, assim como a estimativa de produção de sólidos suspensos totais e em metais em uma ETA convencional que utiliza como coagulante sulfato de alumínio. Para tanto foram coletadas amostras de água de diferentes etapas do tratamento (captação, coagulação, floculação/sedimentação, filtração e estabilização final) e dos resíduos de decantadores e água de lavagem dos filtros ETA/São Carlos-SAAE. Os metais foram determinados em espectrofotômetro de absorção atômica, com pré-concentração de metais em coluna de troca iônica (resina catiônica fortemente ácida). A liberação de material dissolvido foi observada, ao longo das unidades de tratamento; parcela dos sólidos dissolvidos liberados são constituídos de metais dissolvidos ressolubilizados e/ou não removidos. Entretanto, tais afirmações são passíveis de estudos complementares. Na água tratada foram verificadas concentrações de chumbo, acima do limite de 10 &#956/L estabelecido pelo Padrão de Potabilidade, Portaria nº 1469/2000. A partir do balanço de massa e de análises realizadas nos resíduos estimou-se a produção diária de sólidos e de metais, e verificou-se retenção, nos decantadores, principalmente da fração particulada dos metais. A adição de produtos químicos contribuiu com cerca de 37% dos sólidos produzidos na ETA/São Carlos. / The increase in the demand for drinking water and consequently in the generated residues, has taking the Brazilian industry of water, composed of approximately 7500 WTPs, to come across high technical and financial costs in the management of these residues. Metals and solids are the main constituents of the residues generated during the water treatment, either in the sedimentation tank or in filters. Thus the understanding of the production of metals and solids in a WTP is of assumes great importance. This study presents the aspects that involve the presence of metals and solids in the water treatment. The evaluation of the metals in different stages of the treatment, as well as the estimate of the production of solids and metals in a conventional ETA using aluminum sulfate as coagulant have been carried out. Samples of water were collected in different stages of the treatment (raw water, coagulation, flocculation/sedimentation, filtration and finished water) from sludge coagulant and filter backwash waters of WTP/São Carlos-SAAE. The metals were determined in spectrophotomic of atomic absorption, with pre-concentration of metals in column ofionic change (strongly acid resin cationic). The release of dissolved material was observed, along the units of treatment; part of the relesead dissolved solids is constituted by ressolubilized and/or removed dissolved metals. However, such statements are susceptible to complementary studies. In the treated water lead concentrations were verified, above the limit of 10 &#956g/L established by the Standard for Drinking Water, nº 1469/2000. From the mass balance and the analyses accomplished in the residues the daily production of solids and metals, was estimated and retention of mainly particulate fraction of metals was verified, in sedimentation tanks. The addition of chemical products contributed with approximately 37% of the solids produced at WTP/São Carlos.
36

Efeitos do recebimento do lodo da estação de tratamento de água pelo sistema de tratamento de esgoto por lodo ativado em bateladas e aeração prolongada do município de Juquitiba - SP. / Effects of the accepting water treatment plants (WTP) residuals at wastewater treatment plant (WWTP) using SBR activated-sludge process with extended aeration in the city of Juquitiba, SP.

Sundefeld Júnior, Gilberto Carlos 09 May 2007 (has links)
Existem algumas diferentes soluções técnicas de engenharia para a finalidade de tratamento e disposição final dos resíduos gerados em ETA\'s aplicáveis aos diferentes sistemas de tratamento de água. Porém, depara-se com estações consolidadas sem os sistemas de tratamento da fase sólida, onde nem sempre a melhor solução para o tratamento é a mais econômica ou ainda, é a possível de ser implantada. Com isso propôs-se neste estudo avaliar a capacidade da estação de tratamento de esgotos receber os resíduos da ETA, da cidade de Juquitiba - SP, via rede coletora de esgotos, uma vez que existe na ETE o sistema de tratamento dos sólidos ali gerados. Este estudo teve como objetivo verificar as transformações do fósforo e do nitrogênio ao longo do sistema de esgotos, verificar as variações das concentrações de DBO, DQO e sólidos em suspensão, assim como verificar se é possível a manutenção de um equilíbrio consistente controlado pela idade do lodo. A estação de tratamento de água produz resíduos que resultariam em um acréscimo médio de 133 mg/L de sólidos no esgoto e ao longo deste estudo atingiu-se 74 mg/L. Esta contribuição representou, aproximadamente, uma situação em que o porte da ETA é o dobro da ETE receptora dos resíduos. Como conseqüência as concentrações dos sólidos em suspensão totais nos reatores biológicos aumentaram em média 15% e no efluente tratado 73%, ainda a produção de lodo biológico aumentou a ordem de 40%. Ocorreu a diminuição da concentração de fósforo total no efluente tratado da ETE em 29% e 51% para os reatores 1 e 2, respectivamente e da concentração de fósforo solúvel em 74% e 79% para os reatores 1 e 2, respectivamente. Ocorreu a diminuição da remoção média de NKT em 18% e na remoção média de N-NH3 em 13%. Ocorreu, ainda, a diminuição da remoção dos parâmetros DBO e DQO em 4% após o lançamento do lodo da ETA no sistema de esgotos. Pode-se então admitir que ETE\'s pelo processo de lodo ativado com aeração prolongada e com reatores seqüenciais em bateladas são adequados para o recebimento de lodo proveniente de ETA\'s, desde que projetada para atender a essa função complementar, especialmente no que se refere às unidades de desidratação de lodo. / There are different technical engineering solutions for the treatment and final disposal of water treatment plants (WTPs) residuals. Discharge of WTP residual to a wastewater treatment plant (WWTP) is a technical solution in evidence. Therefore, the purpose of this study was to evaluate the capacity of the WWTP using sequencing batch reactor (SBR) activated-sludge process (with two reactors named reactor 1 and 2) in the city of Juquitiba, State of São Paulo, to receive the WTP residuals by gravity sanitary sewers. For this purpose the following points were checked: phosphorous and nitrogen transformations in the sewer systems, variations in BOD , COD and suspended solids (SS) concentrations and the possibility of maintaining a consistent balance system controlled by solids retention time. There was an average increase of 74 mg of suspended solids per liter in incoming sewage by the discharge of WTP residuals to sanitary sewers. Suspended solids concentrations in the biological reactors increased 15 percent in average and 73 percent in the final effluent. Production of waste activated-sludge increased by 40 percent. There was a decrease of 29 percent and 51 percent of total phosphorus concentration in the effluent in reactors 1 and 2, respectively, and of 74 percent and 79 percent of soluble phosphorus concentration in reactors 1 and 2, respectively. Total Kjeldahl nitrogen removal efficiency was reduced by 18 percent and ammonia nitrogen removal efficiency by 13 percent. BOD and DQO parameters for efficiency removal showed a decrease of 4 percent after the discharge of WTP residual to sanitary sewers. In view of these results it can be admitted that WWTPs using sequencing batch reactor activated-sludge process are suitable to receive WTP residuals since adequately designed for this complementary function.
37

Ocorrência de sólidos e metais na água tratada e nos resíduos gerados em ETA convencional de ciclo completo com descargas diárias / Solids and metal occurrence in the drinking water in the residuals generated in conventional WTP of complete cycle with daily discharge

Souza, Francisco Gláucio Cavalcante de 14 July 2004 (has links)
Neste trabalho, foram levantados dados sobre o tratamento da água e os resíduos gerados nos decantadores e filtros da ETA Fonte Luminosa, localizada em Araraquara, que é do tipo convencional com decantadores de alta taxa, objetivando-se obter parâmetros sobre a qualidade e quantidade dos resíduos gerados na ETA referida. Foram analisados e relacionados fatores relevantes na geração e composição destes resíduos, tais como: consumo de produtos químicos, procedimentos operacionais e qualidade da água bruta. O trabalho foi dividido em três etapas. Na primeira, foi realizada a caracterização física e operacional da ETA Fonte Luminosa através de visitas e levantamento de dados históricos da água afluente à estação, da água tratada, dos produtos químicos e dos dados operacionais da estação no período de 2001 a 2003. Na segunda etapa, realizou-se a caracterização qualitativa da água nas diversas etapas do tratamento em termos de pH, cor aparente, turbidez e sólidos; nos resíduos originados nos decantadores e filtros, também, foi realizada a caracterização qualitativa (DQO, nitrogênio total, fosfato total, pH, cor aparente, turbidez e sólidos) e quantitativa (medida e estimada com o emprego de balanço de massas) dos. A ultima etapa, foi a avaliação da ocorrência de metais (Fe, Cd, Zn, Ni, Cu, Pb, Cr e Mg) na água ao longo do tratamento e nos resíduos. Os processos e as operações empregadas no tratamento influenciaram diretamente na qualidade e na quantidade dos resíduos. No período observado, os resultados indicaram grande semelhança entre os resíduos gerados nos decantadores de alta taxa e filtros da ETA Fonte Luminosa. Notou-se grande divergência entre os resíduos gerados em decantadores convencionais (ETA São Carlos) e de alta taxa (descargas diárias). Observou-se a ocorrência de chumbo, níquel e cromo total na água tratada em valores acima do Padrão de Potabilidade fixado pela Portaria nº 518/MS de 25/03/2004. / In this work, it was made a data survey about the water treatment and the residuals generated in the settling tanks and filters from the Fonte Luminosa WTA located at Araraquara-SP, a conventional type WTA with high rate settling tanks; aiming to obtain parameters about the quality and quantity of residuals generated at this WTA. The relevant parameters in the residuals generation and composition, like the chemical consume, the operational proceedings and the raw water quality, were evaluated and related to each other. The work was divided in three stages. In the first, it was made the physic and operational characterization from the Fonte Luminosa WTA by means of visits and historical data surveys from the water that enters the WTA, the treated water, the chemicals used and the operational data from the period of 2001 to 2003. In the second stage, it was made a qualitative characterization from the water in several stages of the treatment, with the parameters: pH, apparent color, turbidity and solids; to the residuals generated in the settling tanks and filters, it was also made the qualitative characterization with the parameters: COD, total nitrogen, total phosphate, pH, apparent color, turbidity and solids; and it was made a quantitative characterization for these residuals (measured and estimated by the mass balance). The last stage was the evaluation of the occurrence of metals (Fe, Cd, Zn, Ni, Cu, Pb, Cr and Mg) in the total water treatment and in the residuals. The processes and operations applied in the water treatment have a direct influence in the quality and quantity of the generated wastes. In the observed period, the results show a great similarity between the wastes generated in the high rate settling tanks and filters from this WTA. It was observed a great difference between the residuals generated in conventional settling tanks (São Carlos WTA) and high rate settling tanks (daily discharge). It was observed the occurrence of lead, nickel and chrome in the treated water, with values bigger than the ones fixed by the Portaria nº 518/MS from 03/25/2004 to a drinking water.
38

Efeitos do recebimento do lodo da estação de tratamento de água pelo sistema de tratamento de esgoto por lodo ativado em bateladas e aeração prolongada do município de Juquitiba - SP. / Effects of the accepting water treatment plants (WTP) residuals at wastewater treatment plant (WWTP) using SBR activated-sludge process with extended aeration in the city of Juquitiba, SP.

Gilberto Carlos Sundefeld Júnior 09 May 2007 (has links)
Existem algumas diferentes soluções técnicas de engenharia para a finalidade de tratamento e disposição final dos resíduos gerados em ETA\'s aplicáveis aos diferentes sistemas de tratamento de água. Porém, depara-se com estações consolidadas sem os sistemas de tratamento da fase sólida, onde nem sempre a melhor solução para o tratamento é a mais econômica ou ainda, é a possível de ser implantada. Com isso propôs-se neste estudo avaliar a capacidade da estação de tratamento de esgotos receber os resíduos da ETA, da cidade de Juquitiba - SP, via rede coletora de esgotos, uma vez que existe na ETE o sistema de tratamento dos sólidos ali gerados. Este estudo teve como objetivo verificar as transformações do fósforo e do nitrogênio ao longo do sistema de esgotos, verificar as variações das concentrações de DBO, DQO e sólidos em suspensão, assim como verificar se é possível a manutenção de um equilíbrio consistente controlado pela idade do lodo. A estação de tratamento de água produz resíduos que resultariam em um acréscimo médio de 133 mg/L de sólidos no esgoto e ao longo deste estudo atingiu-se 74 mg/L. Esta contribuição representou, aproximadamente, uma situação em que o porte da ETA é o dobro da ETE receptora dos resíduos. Como conseqüência as concentrações dos sólidos em suspensão totais nos reatores biológicos aumentaram em média 15% e no efluente tratado 73%, ainda a produção de lodo biológico aumentou a ordem de 40%. Ocorreu a diminuição da concentração de fósforo total no efluente tratado da ETE em 29% e 51% para os reatores 1 e 2, respectivamente e da concentração de fósforo solúvel em 74% e 79% para os reatores 1 e 2, respectivamente. Ocorreu a diminuição da remoção média de NKT em 18% e na remoção média de N-NH3 em 13%. Ocorreu, ainda, a diminuição da remoção dos parâmetros DBO e DQO em 4% após o lançamento do lodo da ETA no sistema de esgotos. Pode-se então admitir que ETE\'s pelo processo de lodo ativado com aeração prolongada e com reatores seqüenciais em bateladas são adequados para o recebimento de lodo proveniente de ETA\'s, desde que projetada para atender a essa função complementar, especialmente no que se refere às unidades de desidratação de lodo. / There are different technical engineering solutions for the treatment and final disposal of water treatment plants (WTPs) residuals. Discharge of WTP residual to a wastewater treatment plant (WWTP) is a technical solution in evidence. Therefore, the purpose of this study was to evaluate the capacity of the WWTP using sequencing batch reactor (SBR) activated-sludge process (with two reactors named reactor 1 and 2) in the city of Juquitiba, State of São Paulo, to receive the WTP residuals by gravity sanitary sewers. For this purpose the following points were checked: phosphorous and nitrogen transformations in the sewer systems, variations in BOD , COD and suspended solids (SS) concentrations and the possibility of maintaining a consistent balance system controlled by solids retention time. There was an average increase of 74 mg of suspended solids per liter in incoming sewage by the discharge of WTP residuals to sanitary sewers. Suspended solids concentrations in the biological reactors increased 15 percent in average and 73 percent in the final effluent. Production of waste activated-sludge increased by 40 percent. There was a decrease of 29 percent and 51 percent of total phosphorus concentration in the effluent in reactors 1 and 2, respectively, and of 74 percent and 79 percent of soluble phosphorus concentration in reactors 1 and 2, respectively. Total Kjeldahl nitrogen removal efficiency was reduced by 18 percent and ammonia nitrogen removal efficiency by 13 percent. BOD and DQO parameters for efficiency removal showed a decrease of 4 percent after the discharge of WTP residual to sanitary sewers. In view of these results it can be admitted that WWTPs using sequencing batch reactor activated-sludge process are suitable to receive WTP residuals since adequately designed for this complementary function.
39

Ocorrência de sólidos e metais na água tratada e nos resíduos gerados em ETA convencional de ciclo completo com descargas diárias / Solids and metal occurrence in the drinking water in the residuals generated in conventional WTP of complete cycle with daily discharge

Francisco Gláucio Cavalcante de Souza 14 July 2004 (has links)
Neste trabalho, foram levantados dados sobre o tratamento da água e os resíduos gerados nos decantadores e filtros da ETA Fonte Luminosa, localizada em Araraquara, que é do tipo convencional com decantadores de alta taxa, objetivando-se obter parâmetros sobre a qualidade e quantidade dos resíduos gerados na ETA referida. Foram analisados e relacionados fatores relevantes na geração e composição destes resíduos, tais como: consumo de produtos químicos, procedimentos operacionais e qualidade da água bruta. O trabalho foi dividido em três etapas. Na primeira, foi realizada a caracterização física e operacional da ETA Fonte Luminosa através de visitas e levantamento de dados históricos da água afluente à estação, da água tratada, dos produtos químicos e dos dados operacionais da estação no período de 2001 a 2003. Na segunda etapa, realizou-se a caracterização qualitativa da água nas diversas etapas do tratamento em termos de pH, cor aparente, turbidez e sólidos; nos resíduos originados nos decantadores e filtros, também, foi realizada a caracterização qualitativa (DQO, nitrogênio total, fosfato total, pH, cor aparente, turbidez e sólidos) e quantitativa (medida e estimada com o emprego de balanço de massas) dos. A ultima etapa, foi a avaliação da ocorrência de metais (Fe, Cd, Zn, Ni, Cu, Pb, Cr e Mg) na água ao longo do tratamento e nos resíduos. Os processos e as operações empregadas no tratamento influenciaram diretamente na qualidade e na quantidade dos resíduos. No período observado, os resultados indicaram grande semelhança entre os resíduos gerados nos decantadores de alta taxa e filtros da ETA Fonte Luminosa. Notou-se grande divergência entre os resíduos gerados em decantadores convencionais (ETA São Carlos) e de alta taxa (descargas diárias). Observou-se a ocorrência de chumbo, níquel e cromo total na água tratada em valores acima do Padrão de Potabilidade fixado pela Portaria nº 518/MS de 25/03/2004. / In this work, it was made a data survey about the water treatment and the residuals generated in the settling tanks and filters from the Fonte Luminosa WTA located at Araraquara-SP, a conventional type WTA with high rate settling tanks; aiming to obtain parameters about the quality and quantity of residuals generated at this WTA. The relevant parameters in the residuals generation and composition, like the chemical consume, the operational proceedings and the raw water quality, were evaluated and related to each other. The work was divided in three stages. In the first, it was made the physic and operational characterization from the Fonte Luminosa WTA by means of visits and historical data surveys from the water that enters the WTA, the treated water, the chemicals used and the operational data from the period of 2001 to 2003. In the second stage, it was made a qualitative characterization from the water in several stages of the treatment, with the parameters: pH, apparent color, turbidity and solids; to the residuals generated in the settling tanks and filters, it was also made the qualitative characterization with the parameters: COD, total nitrogen, total phosphate, pH, apparent color, turbidity and solids; and it was made a quantitative characterization for these residuals (measured and estimated by the mass balance). The last stage was the evaluation of the occurrence of metals (Fe, Cd, Zn, Ni, Cu, Pb, Cr and Mg) in the total water treatment and in the residuals. The processes and operations applied in the water treatment have a direct influence in the quality and quantity of the generated wastes. In the observed period, the results show a great similarity between the wastes generated in the high rate settling tanks and filters from this WTA. It was observed a great difference between the residuals generated in conventional settling tanks (São Carlos WTA) and high rate settling tanks (daily discharge). It was observed the occurrence of lead, nickel and chrome in the treated water, with values bigger than the ones fixed by the Portaria nº 518/MS from 03/25/2004 to a drinking water.
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Tratamento eletroquímico de esgotos sanitários / Electrochemical Treatment for Municipal Sewage

Formentini, Diana Fatima 28 February 2012 (has links)
Made available in DSpace on 2017-07-10T15:14:44Z (GMT). No. of bitstreams: 1 Diana Formentini.pdf: 3787958 bytes, checksum: 0c6f648ab36ecd404919056defc52426 (MD5) Previous issue date: 2012-02-28 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Basic sanitation is a public service with the most deficiency in infrastructure in Brazil, in particular the service of collection and treatment of sewage followed by collection services and waste treatment. The scenary of sanitation in Brazil, especially in the big cities, it becomes increasingly costly and challenging because the population is increasingly concentrated in urban areas. In this regard, it is necessary to adopt minimization and water conservation programs, and the implementation of decentralized treatment systems such as compact units which require a smaller area and offer similar performance. Another concern in the area of sanitation is about the removal efficiency of compounds present in small concentrations in sewage treatment plants as medicines for human and veterinary use, as well as beauty and personal care products. This study aimed to evaluate the efficiency of the electrochemical process (electrocoagulation and electro-oxidation) with three different electrodes (aluminum, iron and graphite) for COD removal in sewage and estimate the energy consumption. Evaluate the electro-oxidation in sewage for the degradation of two drugs (diclofenac and clofibric acid). The aluminum electrodes were more efficient for COD removal and achieved efficiency up to 80% for most of the tests performed. Iron electrodes achieved similar result, but it gives residual color in the effluent. Aluminum electrodes save energy compare with iron and graphite electrodes. The electrochemical process is a promising technique for removal pharmaceutical compounds used in this research. / A maior deficiência do Brasil na área de serviços públicos e infraestrutura é o saneamento básico, em especial o serviço de coleta e tratamento de esgotos sanitários, seguido do serviço de coleta e tratamento de resíduos sólidos. A situação do saneamento básico no Brasil, principalmente nos grandes centros urbanos, torna-se cada vez mais onerosa e desafiadora já que a população está cada vez mais concentrada nas áreas urbanas. Nesse sentido, faz-se necessária a adoção de programas de minimização e conservação de água, além da implantação de sistemas de tratamento descentralizados, como, por exemplo, unidades compactas de tratamento que exigem menor área e oferecem igual desempenho. Outra preocupação na área do saneamento diz respeito à eficiência deremoção de compostos presentes em pequenas concentrações nas estações de tratamento de esgotos como fármacos de uso humano e veterinário, bem como produtos de beleza e higiene pessoal. Dentro desse contexto, o presente trabalho teve como objetivo avaliar a eficiência do Processo Eletroquímico (Eletrocoagulação e Eletro-oxidação) em esgoto sanitário para remoção de DQO, utilizando eletrodos de alumínio, ferro e grafite e estimar o consumo de energia para cada sistema. Avaliou-se ainda o uso da Eletro-oxidação em esgoto sanitário para degradação de dois fármacos (diclofenaco sódico e ácido clofíbrico). A eletrocoagulação com eletrodos de alumínio mostrou-se mais eficiente para remoção de DQO, obtendo eficiências acima 80% para a maioria dos ensaios realizados. Os eletrodos de Ferro apresentaram eficiência semelhante, entretanto, forneceram coloração residual ao efluene final. Os eletrodos de alumínios requerem menor consumo de energia. O processo eletroquímico mostrou-se uma técnica promissora para remoção de determinados compostos farmacêuticos que não sofrem remoção ou degradação pelas técnicas convencionais.

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