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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.
81

Propriedade das normas de lançamento de esgoto / Properties of the norms of sewer release

Amigo, Nisete Augusto de January 1998 (has links)
Made available in DSpace on 2012-09-06T01:11:12Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 106.pdf: 3009480 bytes, checksum: 3073b80b6df5fc1810662a9fd636a233 (MD5) Previous issue date: 1998 / Fundação Oswaldo Cruz. Escola Nacional de Saúde Pública Sergio Arouca. Rio de Janeiro, RJ, Brasil. / As normas utilizadas na avaliaçäo de lançamento de esgotos, NT-202, DZ-205 e DZ-215, foram utilizadas, para verificar se os esgotos domésticos, portanto de origem näo industrial, realmente mantêm esta condiçäo nos dias atuais, década de 90 e com cinqüenta anos de evoluçäo da industria química. O esgoto bruto, estudado, representativo de uma populaçäo de 4000 habitantes, apresentou uma carga orgânica unitária de 98 g/hab.d, maior do que a prevista pela DZ-215, que é de 54 g/hab.d. A concentraçäo de MBAS encontrada, de 6,09 mg/l, é maior que a concentraçäo permitida pela NT-202 para o lançamento industrial, na rede de esgotos, que é de 2,0 mg/l; implica num consumo percapita de surfactante de 2,9 g/hab.d, contra 4,0g/hab.d previstos na Europa Ocidental (Painter & Zabel, 1988) e 4,5 g/hab.d em Owlwood, U.K (Holt, et al., 1995). Os metais pesquisados estäo todos abaixo dos valores preconizados pela NT-202. O cádmio foi o que registrou maior percentual comparado com limite exigido, 29 por cento , seguido igualmente do chumbo e do zinco com 18 por cento, e, ainda, a maior variaçäo percentual de crescimento do consumo percapita. Esse crescimento poderia ser uma tendência ligada ao consumo exagerado, quer por desperdício ou excesso de oferta de produtos, somado, provavelmente, ao controle inadequado desses elementos nos produtos. A relaçäo DBO/DQ, de referência para a NT-205 (FEEMA, 1991) como indicativo da necessidade de implantaçäo de sistema de pré-tratamento de controle de carga orgânica näo-biodegradável, a ser lançada na rede de esgotos, por uma atividade poluidora industrial. Essas tendências devem ser consideradas, para que se busque formas de controle aplicáveis aos esgotos domésticos, ante a expectativa de mais alteraçöes futuras. A carga industrial, pontual, pode ser devidamente controlada para näo agredir o meio ambiente, ou, aos cofres públicos, com demandas näo previstas para as ETE'S. O controle de uma carga difusa - esgoto doméstico - formada pelos mais variados produtos domissanitários, cosméticos e de higiene, exigirá, num futuro próximo, outras formas de controle, para que näo atinja valores que venha a comprometer o tratamento municipal de esgotos e o meio ambiente. / The FEEMA regulations to valuation sewers throwing, NT-202, DZ-205 and DZ-215, were used in order to verify if the domestic sewers, thus of non-industrial origin, really maintain this condition nowadays, in the ninety’s, and with fifty years of evolution of chemical industry. The raw sewer, up in this work, representative of a population of 4.000 inhabitants, presented an unitary organic load of 98 g/cap.d, larger than that expected by DZ-215, that is of 54g/cap.d. The founded MBAS concentration, of 6.09 mg/l, is larger than the NT-202 standard concentration for industrial throwing in the sewerage system, that is of 2.0 mg/l. This imply in a “per capita” surfactant consumption of 2.9 g/cap.d, against 4.0 g/cap.d foreseen in the Western Europe (Painter & Zabel, 1988) and 4.5 g/cap.d in Owlwood, U.K. (Holt, et al, 1995). The researched metals are all lower than the NT-202 standardized values. The cadmium was the one that recorded the larger percentage, compared with the required standard values, 29%, followed equally by lead and zinc with 18%, and yet, the larger percentage variation of “per capita” consumption increase. This increase could be a tendency associated to an excessive consumption, that by wastefulness or a surplus in the products supply, probably added to the inadequate control of these elements in the products. The found average relation BOD/QOD was 0.6 ± 0.17mg/l. The relation BOD/QOD was 2.3±0.7mg/l, having reached in some samples a value higher than 4:1, which value is the background to indicate the necessity of introduction of pre-treatment system (FEEMA, NT-205) as an indicative to control a non-biodegradable organic load, to be thrown in the sewerage system, by an industrial polluter activity. This tendency must be considerate in order to search control lines to be applied in domestic sewers, foreseeing further future changes. The industrial load, can be properly controlled for d’ont pollute the environment or give rise to public costs, with contests unforeseen loads for the ETE’s. The control of a diffuse load - domestic sewer - composed of the most varied household, cosmetics and hygienic products, will demand, in the near future, other lines of control, to the effect of do not reach values that could compromise the municipal sewers treatment and the environment.
82

Corpo, casa e cidade: três escalas da higiene na consolidação do banheiro nas moradias paulistanas (1893-1929) / Body, home and city: three levels of hygiene on the consolidation of the bathroom in the houses of the city of São Paulo (1893-1929)

Clarissa de Almeida Paulillo 17 May 2017 (has links)
A dissertação de mestrado trata da relação entre a implantação das redes de infraestrutura sanitária na cidade de São Paulo e a consolidação do ambiente do banheiro no espaço doméstico entre os anos 1893-1929. Como parte do processo de modernização e saneamento da capital paulista, o Estado assume em 1893 o sistema de distribuição de água e esgotos sanitários, sendo responsável pela ampla difusão dos serviços. Se a relação com a disponibilização das redes é evidente, a definição do banheiro enquanto espaço foi gradual, como se observa nas diferentes soluções para o cômodo encontradas nas plantas residenciais submetidas à municipalidade no período. O cruzamento com outras fontes documentais, relativas à abrangência da cobertura dos serviços sobre o território, aponta que as indefinições do banheiro estiveram ligadas à localização e ao padrão da moradia, revelando a influência do processo desigual de distribuição da água e esgoto na cidade. Além disso, os diferentes modelos nas residências atrelavam-se à reorientação dos costumes da população, sobretudo aos associados aos novos preceitos de higiene dos corpos e dos espaços voltados ao consumo privativo e individualizado da água. / This master degree dissertation is about the relation between the sanitary infrastructure implementation in the city of São Paulo and the consolidation of bathroom in the domestic space between the years of 1893-1929. As part of the modernization and sanitation process of São Paulo\'s capital, the State assumes in 1893 the water supply and waste disposal systems, being responsible for the development of these services. If the relation between the water and waste services is evident, the definition of the bathroom as an architectural space was gradual, as can be seen from the different solutions for this room consulted on residential plans submitted at the city council at the time. The overlapping with other documentary sources, related to the comprehensiveness of the water and waste services over the territory, indicates that the spatial indefinitions of the bathroom were related to local and typologies of houses, unveiling the influence of the unequal process of water supply and waste disposal distribution service in the city. In addition, the different types found in the houses were connected to the reorientation of the inhabitant\'s habits, above all the ones associated to the new hygiene\'s precepts of the body and the spaces for private and individualized consumption of water.
83

Desinfecção de esgotos com radiação ultravioleta : influencia da qualidade do efluente e da fotorreativação

Pires, Marco Roberto 24 June 2002 (has links)
Orientador: Jose Euclides Stipp Paterniani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-02T03:02:10Z (GMT). No. of bitstreams: 1 Pires_MarcoRoberto_D.pdf: 5271302 bytes, checksum: 360fb9a15e870769155cec24f76d1dab (MD5) Previous issue date: 2002 / Resumo: Desinfecção de esgotos com radiação ultravioleta vem sendo utilizado, principalmente, em países europeus e nos EUA. A fotorreativação dos microrganismos tem sido avaliada para determinar seu grau de interferência na desinfecção. Este trabalho teve como objetivo avaliar a radiação ultravioleta para diferentes qualidades de efluentes e estudar a fotorreativação. Foram utilizados dois reatores diferentes, sendo um com lâmpadas emersas e outro imersa. Os reatores foram testados em seis efluentes diferentes para quatro vazões diferentes para cada reator. Os coliformes totais e fecais foram analisados para avaliar a eficiência dos reatores. Ensaios de fotorreativação em condições controladas foram realizadas. De forma geral, o Reator I foi mais eficiente que o Reator TI, e a qualidade do efluente muitas vezes foi mais importante que a dose aplicada como apresentada no Ponto de Coleta 3 para coliformes fecais, em que a inativação foi maior para a vazão 4 (com menor tempo de exposição à luz) em vez de ocorrer para a vazão 1 (com maior tempo de exposição). Doses de radiação ultravioleta mais altas implicam em valores iniciais e finais de fotorreativação menores, porém para atingir o valor máximo necessita de mais tempo. Quanto maior a dose de radiação ultravioleta aplicada menor é o grau de fotorreativação; os coliformes totais tem melhor correlação para análises desta natureza quanto comparado com a E.co/i / Abstract: Disinfection of effluents with ultraviolet radiation has been used in Europeans countries and United States. The photoreactivation of microorganism have been estimated to determine the influence on the disinfection. The objective of this work had to evaluate the ultraviolet disinfection to different qualities of effluent and photoreactivation. Two different kinds of reactors were used in experimental analyzed. The reactors were tested to six different effluents for four flows. Total and fecal coliforms were analyzed to estimate the efficiency of reactors. Assays of photoreactivation were analyzed in controlled conditions. In most of case, the Reactor I was more efficient than Reactor II, and effluent quality was more important than the dose uv applied. Dose uv higher imply in initial and final values of lower photoreactivation. The total coliforms have better correlation than E.coli / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil
84

Public health impacts of storm water canals in Nelson Mandela Bay communities

Papu, Lumka January 2015 (has links)
Public health impacts of storm water canals in Nelson Mandela Bay communities
85

The end of the pipe : integrated stormwater management and urban design in the Queen’s ditch

Murdoch, Scott Philip 11 1900 (has links)
The Queen's Ditch is located three kilometers north of Comox on Vancouver Island and is roughly 1300 hectares in size. In 1998, the watershed experienced a 1 in 200-year rain event that flooded much of the lower watershed. The Regional District of Comox-Strathcona is responsible for land-use planning in the watershed and initiated an investigation into the stormwater runoff problem. This thesis is divided into two components: a planning phase to identify problems with watershed hydrology; and a design phase to illustrate urban design that manages stormwater runoff. Watershed assessments were conducted at the watershed and sub-watershed scale. Watershed assessments were descriptive and helped predict future trends in land-use change. These assessments were not able to identify site specific problems. Sub-watershed assessment was useful at quantifying and identifying stormwater problems. Planners should use sub-watershed hydrological performance to guide land-use planning decisions and assess hydrological and ecological effects of development. The planning phase provides planners with a process to prioritize candidate areas for development, conservation, and rehabilitation. The design phase compares urban design and stormwater performance standards of a proposed conventional design with a sustainable design. The goal of the sustainable design was to mimic the site's natural hydrology to help reduce off-site runoff, and to ensure adequate groundwater recharge. Objectives of the sustainable design were to preserve natural vegetation; maintain x>£ time of concentration; reduce and disconnect impervious surfaces,, and treatment first flush flows. Comparisons of conventional and sustainable designs indicate that stormwater runoff and pollution can be managed at the site level. The sustainable design provides forty-seven percent more dwelling units and exports no stormwater. The sustainable design achieves this without an expensive stormdrain infrastructure. Stormwater is managed at the site level using small infiltration depressions and swales. The design works with the natural hydrological processes of the site to generate a hydrologically sustainable design. Simulated stormwater outputs were used to test and size infiltration ponds and to assess flooding risks. The sustainable design effectively manages stormwater production, runoff, and pollution from storm events ranging from polluted first flush flows to large, flood producing rainstorms. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate
86

Estudio y modelamiento hídrico de geomanta e hidrosiembra como reemplazo de los emboquillados en la carretera Lima-Canta / Study and hydric modeling of geomanta and hydroseeding as a replacement for tipping on the Lima-Canta highway

Mazco Cahuana, Diana Elizabeth, Lecussan Urteaga, Kriss Stephanie 27 October 2020 (has links)
La presente investigación consiste en evaluar y verificar la eficiencia anti-erosiva del revestimiento denominado geomanta e hidrosiembra como reemplazo de los emboquillados de piedra, presentes en las alcantarillas ubicadas en la carretera Lima - Canta. La primera metodología es de enfoque cualitativo, elaborada en campo mediante la recolección de datos mediante fichas, las cuales describen las características de 30 alcantarillas y la verificación del tipo de suelo. Seguidamente, se procesó la información recolectada donde se identificó 08 alcantarillas que presentaban problemas de erosión debido a la falla del emboquillado, posteriormente se procedió a obtener los caudales de diseño y se verifico su dimensionamiento. La segunda metodología presenta un enfoque cuantitativo, donde se determinaron los parámetros de velocidad y esfuerzo cortante generados por el flujo en la descarga de las alcantarillas, dichos valores fueron obtenidos mediante la aplicación de modelos hidráulicos en los programas HEC-RAS e IBER. Con la finalidad de proporcionar la solución adecuada que permita asegurar la estabilidad de la estructura, los valores de velocidades y esfuerzo cortante obtenidos fueron comparados con la resistencia brindada por el emboquillado y la geomanta. Los resultados permiten determinar que el emboquillado no presenta una resistencia adecuada para la protección en la descarga de las alcantarillas a media ladera. Finalmente, se recomienda el uso de geomanta e hidrosiembra para la protección de taludes de fuerte pendiente donde descarguen alcantarillas, en lugar de emboquillados los cuales no presentan resistencias adecuadas ante las velocidades y esfuerzos de corte producidas por el flujo de agua. / The present investigation consists of evaluating and verifying the anti-erosive efficiency of the lining called geomanta and hydroseeding as a replacement for the stone mouthpieces, present in the sewers located on the Lima - Canta highway. The first methodology has a qualitative approach, prepared in the field by collecting data sheets, which describe the characteristics of 30 sewers and the verification of the type of soil. Next, the information collected was processed where 08 culverts were identified that presented erosion problems due to the failure of the mouthpiece, then the design flows were obtained and their sizing was verified. The second methodology presents a quantitative approach, where the velocity and shear stress parameters generated by the flow in the discharge of the sewers were determined; these values were obtained by applying hydraulic models in the HEC-RAS and IBER programs. In order to provide the appropriate solution to ensure the stability of the structure, the values of speeds and shear stress obtained were compared with the resistance provided by the hole and the geomanta. The results allow to determine that the emboquillado does not present an adequate resistance for the protection in the discharge of the sewers to the middle slope. Finally, the use of geomatting and hydroseeding is recommended for the protection of steep slopes where culverts discharge, instead of troughs which do not present adequate resistance to the speeds and shear stresses produced by the water flow. / Tesis
87

Advancing Understanding of Green Infrastructure Performance Through Field Measurements and Modeling

Wang, Siyan January 2020 (has links)
Urbanization has posed great challenges for environmental sustainability, human health, and wellbeing. One of these challenges is stormwater management stemming from widespread imperviousness in urban areas. For many cities, including New York City, stormwater management issues are being exacerbated by the impacts of climate change, which is increasing the frequency and intensity of wet weather flows in multiple regions of the world. In New York City, stormwater runoff is collected with wastewater sewage in a combined sewer system (CSS) that dates back to over a century ago. At the time the system was put in place, it was designed to transport a combination of storm and wastewater to local treatment plants with a capacity of about twice the dry-weather flow. With the expansion of urbanization and population growth, this outdated system is now easily overwhelmed during wet weather flow. In some areas of the City, rainfall of less than a few millimeters can cause untreated combined storm and waste water in excess of the system’s capacity (Schlanger, 2014), to be discharged directly into a nearby surface water. The combination of storm and wastewater is referred to as combined sewerage, and overflow events are referred to as combined sewer overflows (CSOs). CSOs are a leading source of local water body pollution in NYC, as well as countless other older cities in the US and abroad that operate with combined sewer systems. To solve the CSO problem, many cities, including NYC, have adopted green infrastructure (GI) plans that aim to capture stormwater locally before it can make its way into a CSS. In New York City, right-of-way bioswales (ROWBs) are composed of about 60% of the GI that has been implemented to date (The New York City Department of Environmental Protection, 2020) for stormwater management and CSO reduction. However, despite the popularity of ROWBs as a GI intervention, few research studies have focused on quantifying their hydrological performance. This can be attributed, in part, to the greater complexity of ROWB behavior in comparison to other GI interventions, such as green roofs, which have attracted wider research interest. In addition, because ROWBs are located in the public right-of-way, monitoring and measurement of the behavior of these systems also poses additional challenges. The first study in this dissertation presents three new field methods for quantifying the stormwater retention capacity of individual ROWBs. By applying the field methods at a ROWB site located in the Bronx, NYC, the influence of rainfall characteristics and the monitored soil moisture content of the ROWB on the ROWB’s hydrological performance was explored. A definition of a so-called ‘rain peaky event’ (RPE) was introduced to divide an individual storm into several sub-events. A RPE event-based empirical model for predicting the stormwater retention behavior of the ROWB was then developed based on the monitored soil moisture content of the ROWB and the rain depth recorded every 15 minutes during a storm event. This study found that the predicted stormwater retention volume per rain depth per unit drainage area of the studied ROWB, is not significantly different from that of several NYC based extensive green roofs. However, compared to the drainage area of the green roofs, which is the same as the roof’s surface area, the drainage area of the studied ROWB was about 84 times its surface area. Thus, per unit area, the ROWB was found to have significantly higher (almost two orders of magnitude) total stormwater capacity than the extensive green roofs. The second study in this dissertation assessed the applicability of the physics-based one-dimensional finite element model HYDRUS-1D, for simulating the infiltration process of a ROWB during storm events using long-term monitored soil moisture content as an input. The simulation results from the HYDRUS-1D was validated by field measurement results taken at the ROWB site located in the Bronx, NYC, and compared with the RPE event-based empirical model presented in the first study. The HYDRUS-1D model was found capable of predicting the ROWB’s cumulative stormwater retention at intervals of one minute, as well as the total retention volume of stormwater inflows into the ROWB per rain peaky event, except for events with an average stormwater inflow intensity high than 20 cm/hr. The study revealed that HYDRUS-1D has a tendency to under-predict the retention capacity of the studied ROWB for a storm with an inflow intensity high than 20 cm/hr, thus providing a lower bound on ROWB stormwater retention. The current published version of the HYDRUS-1D was also found to be erroneous when simulating the ROWB stormwater infiltration process in cases where the ROWB’s soil moisture content was close to saturation. The third study investigated the effectiveness of increased perviousness on CSO reduction and water quality improvement in NYC, toward an aim of understanding how GI implementation can improve city-wide stormwater management issues. By using the enterococci (ENT) concentration as an indicator of water quality and the runoff coefficient to represent land perviousness over an area, a random forest classification model was developed for predicting whether a water body is swimmable or not at 50 shore sites along the main waterways of NYC. The model revealed the significant contribution of land perviousness, and hence GI interventions and green space, to CSO pollution reduction for CSO-shed areas located adjacent to slower-moving waterways. For CSO-shed areas located adjacent to faster moving waterways, the influence of land perviousness was found to be negligible. The random forest classification model developed in this third study can be used as a tool for city planners and agencies as part of plans for GI implementation that focus on the optimization of local water quality, among other objectives. Overall, the research presented in this dissertation aimed to provide a deeper insight into the factors governing the hydrological performance of the most prevalent GI in NYC – namely right-of-way bioswales. In addition, the research aimed to provide insight into linkages between land perviousness and CSO pollution levels in NYC local waterways, which can be used to inform the implementation and overall performance of the entire NYC GI system.
88

Vývoj vysoce odolného kompozitu s využitím druhotných surovin a taveného čediče / Development of highly resistant composite using secondary raw materials and cast basalt

Černý, Pavel January 2019 (has links)
The diploma thesis deals with development of high resistant composite, which brings its properties closer to the melted basalt products. This fact will allow substitution of basalt elements in hostile chemical environment by newly developed material and completes its product line. High resistant composite also consists of secondary raw material in highest possible amount. Material that is being evolved carries high strength, abrasion resistance and is also resistable in hostile chemical environment.
89

Studie variant odkanalizování vybrané obce / Study of variants of sewer network of selected village

Marková, Lada January 2012 (has links)
The subject of the master's thesis is study of variants of sewer network of Nezamyslice by gravity, pressure and vacuum sewers. The proposed alternative solutions are then techno-economically evaluated.
90

Tratamento de esgotos domésticos por reator anaeróbio de fluxo ascendente e manto de lodo reator UASB / Treatment of domestic sewage by upflow anaerobic reactor and UASB reactor sludge mantle

Vieira, Sonia Maria Manso 20 February 1997 (has links)
O tratamento de esgotos é essencial à manutenção de suprimento de água nos centros urbanos em condições desejáveis à saúde pública. A carência de saneamento em nosso país mostra a necessidade de alternativas tecnológicas para o tratamento de esgotos. Na busca de novas opções, iniciou-se na CETESB em 1983, o estudo de sistemas compactos para tratamento direto de esgotos pela via anaeróbia. O reator anaeróbio de fluxo ascendente e manto de lodo (reator UASB) foi estudado em escala piloto e mostrou-se viável e eficiente, levando à necessidade de se efetuar o aumento de escala para o completo desenvolvimento da tecnologia. Um reator UASB de 120 m3 foi construído. Durante sete anos (de 1987 a 1993) funcionou sob observação, o que possibilitou o domínio da tecnologia. O sistema operou à temperatura ambiente em três períodos distintos. No primeiro período estudou-se as eficiências de remoção de matéria orgânica e a produção de gás e de lodo. Com tempo de retenção hidráulica médio de 6,5 horas, obteve-se efluente com 113 mg DQO/L, 48 mg DBO/L e 39 mg SST/L. As eficiências de remoção de DQO, DBO e SST foram respectivamente de 59, 65 e 76 por cento. A remoção de Coliformes totais e fecais ficou entre 70 e 90 por cento. Sua desinfecção através de métodos convencionais como cloração, ozonização ou radiação ultravioleta mostrou-se eficiente, a exemplo da maioria dos sistemas secundários de tratamento de efluentes. Obteve-se como fator de produção de lodo 0,2 kg ST/kg DQO da alimentação, sendo esta baixa produção de lodo uma das grandes vantagens do processo anaeróbio tendo em vista o custo e o trabalho que representam o tratamento e disposição do lodo no tratamento de esgotos. A produção de gás foi de 120 NL/kg de DQO alimentado. Efetuou-se também o acompanhamento microbiológico do lodo através de metodologia específica de acompanhamento de biomassa de biodigestores, o que possibilitou o aprimoramento dos conhecimentos da formação da biomassa no decorrer do processo. No segundo período de operação comprovou-se os resultados obtidos no primeiro período. No terceiro período de operação, apoiando-se nas técnicas de análise microbiológica da biomassa, estudou-se a partida a fim de diminuir o tempo para se atingir o regime estacionário. A utilização de inóculo não adaptado, como o lodo de esgoto de reator convencional, requer três a quatro meses para atingir o estado estacionário, com as eficiências relatadas. A partir da experiência adquirida são efetuadas recomendações e considerações para dimensionamento, partida, operação, manutenção e monitoramento para servir como guia aqueles que forem utilizar esta nova tecnologia. Após a partida o sistema apresenta reprodutibilidade, confiabilidade e estabilidade de operação. O controle do sistema, quando se trata de esgoto doméstico, é bastante simples, necessitando apenas remoção periódica de lodo, além da manutenção e limpeza. Há necessidade de remoção periódica de escuma. O dimensionamento do reator sofreu aperfeiçoamentos para melhorar a separação das três fases sólida, líquida e gasosa. Além dos critérios adotados anteriormente a partir do reator piloto de 106 L que possibilitou o estabelecimento de critérios como velocidade superficial no decantador de O,7 m3/m2/h, velocidade do líquido através da abertura inferior do decantador de 5 m3/m2/h e inclinação das paredes do decantador de 50°, observou-se que o transpasse entre a parede do decantador e do defletor de gases deve ter no mínimo 15 em para assegurar que o gás não desvie para dentro do decantador. O limite de velocidade no corpo do reator não deve ultrapassar 1 m3/m2h para garantir o acúmulo de lodo no reator. O lodo apresentou granulação com diâmetros de até 2 mm. Os processos de pós tratamento que vem sendo testados dão os polimentos necessários e adequados às diversas condições de reuso ou descarte do efluente. O sistema é hoje relativamente bastante utilizado, quando se leva em conta os parcos investimentos havidos no setor nos últimos anos. No Estado de São Paulo, a aplicação desta tecnologia foi efetuada através de um convênio entre a CETESB e o DAE-Sumaré, no Jardim Santa Maria, um loteamento de 1500 habitantes. Esse trabalho, mostrou a viabilidade de sua aplicação e comprovou os resultados obtidos, assim como várias experiências realizadas por outras instituições com processo anaeróbio também o demonstraram. No Estado do Paraná, o processo anaeróbio tem sido empregado sistematicamente para o tratamento de esgotos pela Companhia de Saneamento daquele Estado, a SANEPAR. A divulgação dessas experiências e de tantas outras existentes, deve proporcionar a confiança na tecnologia possibilitando sua expansão e a melhoria da qualidade de nossas águas. / Sewage treatment is essential to water supplying in urban nuclei with desirable conditions of public health. The lack of sanitation in our country shows the necessity of sewage treatment technologies compatible to our reality. Searching for new technologies, CETESB has started in 1983, the study of new compact anaerobic treatment systems for sewage. The UASB reactor was studied in pilot scale showing the need of scaling up for it\'s complete technological development. For this purpose a 120m3 UASB reactor was built. During seven years (from 1987 to 1993) the system worked with methodological observation, which made possible the mastering of the technology. The system operated at ambient temperature in three distinct periods. In the first one the performance of organic matter removal and the gas and sludge production were studied. The results showed effluent with 113 mg COD/L, 48 mg BOD/L and 39 mg SST/L with 6.5 hours of hydraulic retention time. The COD, BOD and SST removal performances were respectively 59, 65 and 76 per cent. The faecal and total Coliform removal showed values between 70 and 90 per cent. The effluent disinfection by conventional methods as chlorination, ozonation and ultra violet radiation has showed to be efficient, as the majority of effluent secondary treatment systems. The sludge production was 0.2 kg ST/kg COD in the feed. This low sludge production is one of the biggest advantages of the anaerobic process, in view of the costly and great disturbances that represent the sludge treatment and disposal in the sewage treatment. The gas production was 120 NL/kg COD of the feed. The biomass growth was followed by means of a microbilogical analysis specially developed for biodigesters sludge. In the second operation period the results were confirmed. In the third operation period, also followed by means of microbiological technical analysis, the shortening of the start up time was studied. It was found that starting up with unacclimatized inoculum, the stationary condition takes three to four months to be achieved, with the performances related. Based on the experience gathered, recommendations are made for system design, start up, operation, maintenance and monitoring. After the start up, the system shows reproducibility, reliability and stable operation. For essentially domestic sewage, the control system is very simple, necessitating only periodical sludge removal in addition to the maintenance activities. There is necessity of periodically scum removal. The design of the reactor was changed to improve the separation of solid, liquid and gaseous phases. Besides the design criteria described before, based on pilot scale experience, such as surface velocity in the settler area of O.7 m3/m2.h, liquid velocity in the lower aperture of the settling chamber 5 m3/m2.h with minimum HRT of four hours and slope of settling chamber walls of 50°, it was observed that it needs 15 cm in the crossing between the settler wall and the gas deflector to assure no gas deviation to the settler compartment. The maximum upflow velocity in the reactor body is 1 m3/m2.h to warrant retention of sludge in the reactor. Pellets in sludge presented up to 2 mm in diameter. Post-treatments may be necessary to give the effluent the appropriated conditions for its reuse or discharge. Today, the system is quite used in Brazil, taking in account the low investments in the sector. In the State of Sao Paulo, an example of this technology transfer is the agreement signed by CETESB and DAE-Sumaré, at \"Jardim Sta. Maria\", a small community of 1500 inhabitants. This work confirmed the results obtained and showed the feasibility of its application. Other experiences made by other institutions with anaerobic process confirmed them as well. In the State of Parana, the anaerobic process has been employed systematically for sewage treatment by the State Sanitation Company. The diffusion of this experiences and of many others existing might provide the confidence in the technology, enabling its expansion and the improvement of the quality of our waters.

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