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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.
91

Concepção e estudo de uma unidade compacta para tratamento preliminar de esgoto sanitário composta por separador hidrodinâmico por vórtice e grade fina de fluxo tangencial / Designing and study of a compact unit for sewage preliminary treatment made up of a hydrodynamic vortex separator and a tangential flux fine screen

Gustavo Silva do Prado 15 September 2006 (has links)
Atualmente, existe uma tendência entre os projetistas brasileiros de valorizar a etapa de tratamento preliminar em projetos de novas estações de tratamento de esgoto (ETE). Neste ensejo foi concebido, construído e estudado um protótipo, em escala plena, de uma unidade composta de separador hidrodinâmico por vórtice (SHV) – empregado como desarenador – e grade fina cilíndrica de fluxo tangencial. Estudos acerca da hidrodinâmica da unidade, fundamentados em ensaios de estímulo-resposta com traçador (sal de cozinha) e simulações computacionais do padrão de escoamento em software de dinâmica dos fluidos computacional, demonstrou que ao se operar a unidade com taxas de aplicação superficial (TAS) de 764 'M POT.3'/'M POT.2'd; 1.146 'M POT.3'/'M POT.2'd e 1.528 'M POT.3'/'M POT.2'd o regime de macro-mistura do padrão de escoamento que se desenvolve no SHV aproximou-se do plug-flow, porém com certo grau de mistura que diminuiu com o aumento da TAS. Nesta pesquisa, foram desenvolvidos dois métodos um para determinação da concentração de areia no esgoto sanitário e outro para determinação da distribuição granulométrica dos grãos dessa areia. Ambos foram empregados na avaliação de desempenho da unidade de tratamento preliminar desenvolvida, que foi realizada na estação elevatória de ETE Jardim das Flores do município de Rio Claro, SP. Durante esta fase da pesquisa, o SHV demonstrou enorme potencialidade na remoção de areia para as TAS de 764 'M POT.3'/'M POT.2'd; 1.146 'M POT.3'/'M POT.2'd e 1.528 'M POT.3'/'M POT.2'd, porquanto, além de não remover significativamente matéria orgânica particulada (medida em termos de concentração de sólidos suspensos voláteis) presentes no esgoto sanitário, a unidade atingiu eficiências de remoção de grãos de areia de tamanho maior ou igual a 200 'mü'm entre 85% e 95%. Entretanto, a grade fina cilíndrica de fluxo tangencial (auto-limpante) revelou-se inviável. / Currently, there is a trend among the brazilian designers of valorizing the preliminary treatment in recently designed wastewater treatment plants (WWTP). In this context, a full scale prototype of a unit made up of a hydrodynamic vortex separator (HVS) – applied as a degritter – and a tangential flux fine screening was designed, built and evaluated. Research about the hydrodynamic of the prototype, based on stimulus-response essays with a salt tracer (sodium chloride) and computational simulations of the flow pattern using the computational fluid dynamic (CFD) software, showed that the macro mixture regime of the flow was similar to a plug-flow when the unit was operated with superficial loading rates (SLR) of 746 'M POT.3'/'M POT.2'd; 1.146 'M POT.3'/'M POT.2'd and 1.528 'M POT.3'/'M POT.2'd, however, the flow presented a certain mixture degree that reduced with the SLR increase. In this research, two methods were developed: one for the determination of grit concentration in sewage and another one for the assessment of grit grading. Both methods were used on the evaluation of the HVS prototype efficiency, which was carried out at Jardim das Flores WWT, in the city of Rio Claro, SP. During this phase of the research, the HVS presented a great potential for grit removal when the SLR of 746 'M POT.3'/'M POT.2'd; 1.146 'M POT.3'/'M POT.2'd and 1.528 'M POT.3'/'M POT.2'd were applied; for the reason that, besides not significantly removing the particulate organic matter present in sewage (measured as volatile suspended solids), the unit achieved grit removal efficiencies in the range of 85% to 95% for grit equal to or large than 200 'mü'm. However, the tangential flux cylindrical fine screening (self cleaning) did not reveal feasibility.
92

Evaluación de la calidad del concreto hidráulico usando agregado fino marginal en el proyecto rehabilitación y mejoramiento de la carretera DV. Imperial – Pampas

Paredes Carrasco, Alexander Edward, Guillen Herrera, Edson Rodolfo January 2015 (has links)
Para la presente investigación de tesis desarrollada entre los distritos de Imperial y Pampas, provincia de Tayacaja, en el departamento de Huancavelica, se tiene como unidad de análisis a 60 muros de contención, donde se aplicó criterios muestréales de 23 muros f´c 210 kg/cm2. Como resultados alcanzados se logró elaborar concreto hidráulico de calidad usando agregado fino marginal con el cual se pudo satisfacer los parámetros de resistencia y durabilidad. Para demostrar la durabilidad se realizaron distintos ensayos; los que no cumplieron con las especificaciones de la norma EG-2000 fueron el de Equivalente de arena MTC E 114, Material que pasa el Tamiz N°200 MTC E 202 y Análisis granulométrico por tamizado ASTM C 136, por lo cual se efectuaron análisis más rigurosos como: el ensayo de Valor de azul de metileno y el ensayo de Análisis petrográfico macroscópico y microscópico en agregados para concreto ASTM C 295, donde se obtuvo como resultado que la arena no presenta elementos activos en su composición, lo que quiere decir que ante las condiciones ambientales de la zona estos elementos no se expanden ni se contraen y adicionalmente como medida de control se diseñó la mezcla de concreto hidráulico con aditivo incorporador de aire AirMix-200. Del mismo informe petrográfico se concluyó que la composición principal del agregado es la caliza, la cual es materia prima para la elaboración del cemento, que de alguna manera adicional ayuda a cumplir satisfactoriamente el parámetro de resistencia. Así mismo quedó demostrado que a través de ensayos a compresión no confinada de testigos de concreto, se alcanzó resistencias superiores a lo requerido en la norma EG-2000. Research for this thesis developed between the districts of Imperial and Pampas, Tayacaja province, in the department of Huancavelica, it has the analysis unit 60 retaining walls, where 23 sample criteria applied walls f´c 210 kg/cm2. Results obtained are as elaborate hydraulic concrete achievement of marginal quality using fine aggregate with which it was able to satisfy the parameters of strength and durability. To demonstrate the durability various tests were performed; those who do not comply with the specifications of the EG-2000 were rule the sand equivalent MTC E 114, passes what material the sieve No. 200 MTC E 202 and sieve analysis ASTM C 136, here by which they were made Analysis More rigorous like: The test value of methylene blue and testing of macroscopic and microscopic petrographic analysis in paragraph aggregate concrete ASTM C 295, where it resulted the sand without presents elements active in their composition, which means they say to the area Environmental Conditions These elements do not expand or contract and additionally as a control measure of self-design hydraulic concrete mix with entraining admixture AirMix-200 air. Same petrographic report concluded that the composition of the director of aggregate is limestone, which is a raw material for the production of cement, which in some additionally helps one perform satisfactorily resistance parameter. Also it demonstrated that one through essays of unconfined compressive concrete witness, higher strengths than required was reached in the EG-2000 standard.

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