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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

A feasibility study on treated effluent re-use in Hong Kong

Ho, Wai-yee, Stephenie., 何慧怡. January 2003 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
82

A study of the applications of recycling rainwater in Hong Kong

Tse, Pak-wing., 謝柏榮. January 2004 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
83

Economic feasibility of selective adjustments in use of salvageable waters in the Tucson region, Arizona.

DeCook, K. James(Kenneth James),1925- January 1970 (has links)
Water in the Tucson region is a limited resource. Ground water has been developed in the past as a primary source of water to supply all uses, and the present possibility emerges that the output products of this system of uses can be salvaged and combined with the primary source for further use. A water-salvage industry is conceived in which the outputs of water uses, augmented by storm runoff, become the inputs to the industry; water treatment is the main activity of the industry; and water of improved levels of quality is its principal output. The regional sources of salvageable water are defined as 1) domestic-industrial effluents from the metropolitan sewage collection and disposal system, 2) domestic and industrial effluents from isolated locations, called discrete sources, and 3) storm runoff from both urban and non-urban watersheds. At the 1970 level the available quantity of such waters is estimated to be in excess of 35,000 acre-feet per year and increasing. Historically, only the first of these classes of water has been salvaged and reused in the Tucson region, and then only for irrigation of fiber, field, and forage crops. The current level of treatment technology is adequate to upgrade the quality of any or all of these salvageable waters to the requirements of additional agricultural as well as recreational and industrial uses. What needs to be determined is the degree of economic feasibility of allocating the salvaged waters to these uses under the prevailing institutional constraints. The selected types of potential uses in the water reuse subsystem are industrial uses as represented by power plants and by mining and milling operations, the recreational uses of urban fishing and boating activities and park irrigation, and agricultural uses in the form of irrigation of field and forage crops, cotton, orchard, and produce. Each of the classes of use is embodied in an industry which realizes a net return to the water input. An urban recreation survey indicates, for example, that under maximum intensity of use the net returns to water for fishing and boating might be as much as $500 per acre-foot. The objective relative to all uses is to maximize aggregate net returns to water from the combined supply, and the measure of effectiveness is a net benefit function representing the difference between gross benefit and incremental cost for water in each activity. The available salvaged waters are substituted incrementally for ground water in the total regional water supply function. Calculated numerical examples of allocation of combined supplies, in a linear programming format with restraining institutional conditions, demonstrate that under optimal allocation the treated municipal-industrial effluent would be used to some extent to serve not only agricultural but recreational and industrial uses. This result is attributable in part to the condition that the metropolitan water agencies bear the obligation of primary and secondary treatment at no direct cost to the user. Under benefit maximization this effluent also could serve a significant part of the water needs of the remote mining operations; under existing institutional arrangements, however, this industry is minimizing cost by pumping from the nearest available ground-water source. Preliminary calculations indicate that structural adjustments involving construction of new facilities in the Tucson region for the utilization of salvaged waters could be economically justified, their feasibility being highly sensitive to the extent of use for urban recreational activities.
84

Reutilização da água de resfriamento do mosto em uma cervejaria nacional /

Mendes Junior, Antonio Aparecido. January 2019 (has links)
Orientador: Zacarias Xavier de Barros / Banca: Rogério Lopes Vieites / Banca: Juliana Arruda Ramos / Banca: Pricila Veiga dos Santos / Banca: Igor Otávio Minatel / Resumo: A água é um recurso natural indispensável para todos os seres vivos presentes no planeta Terra. A utilização deste recurso natural engloba os mais variados processos produtivos, como a agricultura, pecuária, indústrias entre outros. Com o passar dos anos, esse recurso vem ficando cada vez mais raro, por isso a necessidade da preservação natural vem ganhando mais espaço. Com o aumento da população mundial ao longo das décadas, observa-se uma grande reestruturação no aspecto produtivo, onde o homem foi obrigado a desenvolver novas técnicas de produção, para assim, alcançar um aumento na produção e na produtividade de alimentos e matérias-primas. Nesse sentido, tornou-se uma realidade a utilização de grandes quantidades de água nos processos de produção. Com isso fica claro que a única maneira de obter-se um crescimento sustentável é a partir de processos de produção que utilizem o mínimo de água possível para a elaboração de seus produtos. Nesse estudo, analisou-se a quantidade de água utilizada no processo produtivo de uma cervejaria. Assim, o presente trabalho teve por objetivo geral demonstrar e quantificar a utilização da água nos processos produtivos para a fabricação de cerveja, através do mapeamento dos processos de produção, utilizando como ferramenta a elaboração de um fluxograma de processo, para assim desenvolver formas de diminuir o consumo de água no processo de produção. Já o objetivo específico se baseou na avaliação entre o fluxograma de processo existente na in... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The water is an indispensable natural resource for all living beings present on planet Earth. The use of this natural resource goes from this all productive processes, encompassing agriculture, livestock and industries among others. With the passing of the years this resource is becoming more and more in short supply, with that the need of the natural preservation has been gaining more space. With the increase of the world population over the decades, there is a great restructuring in the productive aspect, where man was forced to develop new production techniques, in order to achieve an increase in the production and productivity of food and raw materials. In this sense, the use of large amounts of water in the production processes has become a reality. This makes it clear that the only way to achieve sustainable growth is from production processes that use as little water as possible to produce their products.In this study, the amount of water used in the production process of a brewery was analyzed. The aim of the present work was to demonstrate and quantify the use of water in the production processes for brewing, through the mapping of the production processes, using as a tool the elaboration of a process flow diagram, in order to develop ways of reducing water consumption in the production process. The specific objective is based on the evaluation between the process flow diagram in the industry and the process flow developed with the improvements in water consumption. The hypothesis that guides this study is that in the production process of a Brazilian brewery, to produce 1 liter of the finished product, lager beer, from 8 liters of water are used. It is observed, a great consumption of water for the manufacture of this product highly consumed by the Brazilians. The results are based on the analysis of the beer production flow chart based on the production process. The results show that in ... / Doutor
85

Reuso de água na lavagem de veículos. / Water reuse for carwash.

Morelli, Eduardo Bronzatti 07 June 2005 (has links)
O presente trabalho apresenta, em primeiro lugar, um levantamento bibliográfico sobre a conceituação de “reuso de água" em todas as suas modalidades. A seguir, uma análise da situação atual desta prática na Região Metropolitana de São Paulo, apresentando estudos em andamento na Companhia de Saneamento Básico do Estado de São Paulo – Sabesp e os aspectos relativos à elaboração de legislação específica sobre o assunto no país. Dando ênfase à reutilização das águas para lavagem de veículos, apresenta o que já existe nesta área no Brasil. Descreve alguns sistemas de tratamento que propiciam a recirculação do efluente proveniente da lavagem de veículos, citando suas etapas, processos utilizados, vantagens e desvantagens. São apresentados dados técnicos relativos à implantação, funcionamento e manutenção de sistemas de reuso, observados em visitas técnicas a uma empresa de transporte de passageiros e a alguns postos de lavagem de automóveis, localizados na cidade de São Paulo. Por fim recomendam-se dois tipos de sistemas para recirculação de água proveniente da lavagem de veículos. Um desenvolvido com recursos próprios, baseado em processos de floculação e sedimentação e outro adquirido de empresa especializada que utiliza o processo de flotação. Chegando-se a conclusão de ser possível a reciclagem e o reúso de águas em empresas deste ramo de atividade, ou similares, conforme a necessidade de aplicação, reduzindo-se de 70 a 80% os custos com a água de lavagem dos veículos, adequando processos e contribuindo para a preservação do meio ambiente. / The present work presents, in the first place, a bibliographical survey on the conceptualization of "water reuse" in all its modalities. To follow, an analysis of the current situation of this practice in the São Paulo´s Metropolitan Region, presenting studies in progress in the Companhia de Saneamento Básico do Estado de São Paulo - Sabesp and the relative aspects in the Legislation on the subject in the country. It describes some of the treatment systems that make possible the recirculation of the effluent deriving from car wash, citing its stages, used processes, advantages and disadvantages. There are some technical information about the implamentation, functioning and maintenance of systems of reuse, observed in technical inspections to a company of transport of passengers and to some ranks of car wash stations, located in the city of Sao Paulo. In conclusion, there is the possibility of recycling and reusing the waters in companies in this line of activity, or similar, as the necessity of application, reducing costs (70 – 80%), adjusting processes and contributing to the preservation of the environment. Finally, two types of systems are recommended for water recirculation deriving from car wash.
86

Reúso de água em sistemas aeroportuários utilizando o processo de ultrafiltração. / Water reuse in airport systems using ultrafiltration process.

Rodrigues, Luana Di Beo 20 August 2012 (has links)
O intenso crescimento populacional associado à demanda excessiva de água, principalmente em grandes centros urbanos, tem comprometido de forma significativa os recursos hídricos tornando-os escassos em muitas regiões. Frente a este cenário a adoção de medidas que proporcionem a conservação da água nas diversas atividades nas quais ela é utilizada é de grande relevância. Neste contexto, medidas como o uso racional e a prática do reúso de água são opções que devem ser consideradas para combater a escassez induzida. No caso do reúso de água é possível utilizar efluentes, tratados ou não, como fonte alternativa às demandas para usos menos restritivos, preservando a água de melhor qualidade para aplicações mais nobres, como o consumo humano. Assim, neste trabalho foi avaliada a viabilidade técnica da utilização de efluentes secundários submetidos ao tratamento complementar por membranas de ultrafiltração, do tipo fibra oca, para atendimento de demandas não potáveis em sistemas aeroportuários. O estudo foi desenvolvido através da operação de uma unidade piloto de membranas, instalada na saída do sistema de esgotamento sanitário do Aeroporto Internacional de São Paulo/Guarulhos Governador André Franco Montoro. Por meio de ensaios específicos as condições ótimas de operação foram estabelecidas, pressão de 0,9 bar (90 kPa), frequência de retrolavagem de 40 minutos e frequência de limpeza de 200 h, sendo que a taxa de recuperação de água no sistema permaneceu em torno de 70%. O desempenho do sistema em relação à remoção de contaminantes foi avaliado verificando-se as porcentagens de remoção de Cor, Turbidez, DBO5,20, DQO, Carbono Orgânico Dissolvido, Absorbância de radiação UV (254 nm) e Coliformes Termotolerantes, obtendo-se remoções de 89%, 99%, 70%, 78%, 80%, 36% e 100%, respectivamente. Com base nos resultados das análises foi possível concluir que a água produzida pelo sistema de membranas apresenta potencial para atender aos seguintes usos não potáveis: irrigação de áreas verdes, descargas em bacias sanitárias e mictórios, lavagem de pitas e reserva para combate a incêndios. Como a água produzida pelo sistema de membranas apresentou concentrações elevadas de Nitrogênio Amoniacal, Fosfato e Matéria Orgânica recomenda-se um estudo mais detalhado da estação de tratamento biológico, antes de utilizar para atender a esse fim. / The excessive demand for water associated with intense population growth, principally in large urban centers, has significantly compromised water resources and transformed the situation in many regions to a scarcity status. Faced with this scenario, it is of great relevance to adopt measures that promote the conservation of water, through various activities and uses. In this context, rational water use and water reuse are measures that should be considered to tackle the induced shortage. In the case of water reuse, it is possible to use effluents, treated or untreated, as an alternate source for uses that have less stringent quality standards. This in turn, preserves the higher quality water for more demanding water uses, such as human consumption. In this study, we evaluated the technical feasibility of the use of secondary effluents, subjected to ultrafiltration membrane treatment (hollow fiber), to meet the non-potable demands of airport systems. The study was conducted with a pilot plant membrane, installed and operated at the sewage system discharge at the International Airport of São Paulo/Guarulhos Governor André Franco Montoro. Specific tests were conducted to establish optimum operation conditions: 0.9 bar (90 kPa) of pressure, a backwash frequency of 40 minutes, a cleaning frequency of 200 hours, and a recovery rate maintained around 70%. The system performance with respect to contaminant removal was evaluated by determining the percent removal of color, turbidity, BOD5, 20, COD, dissolved organic carbon, UV Absorbance (254 nm), and coliform, which yielded removals of 89%, 99%, 70%, 78%, 80%, 36%, and 100%, respectively. Based on analysis results, it was concluded that the water produced by the membrane system has the potential to supply the following non-potable uses: irrigation of green areas, discharges in toilets and urinals, floor washing, and firefighting reserves. As the water produced by the membrane system had high concentrations of ammoniacal nitrogen, phosphate, and organic matter, a more detailed study is recommended before using the effluent in cooling towers.
87

Viabilidade de reúso de efluente tratado em indústria de galvanoplastia /

Rocha, Luana Cristina Pereira. January 2019 (has links)
Orientador: Gustavo Henrique Ribeiro da Silva / Banca: Luiz Antonio Daniel / Banca: Ana Flávia Vieira Pontes de Moraes / Resumo: O aumento da demanda de água para as diversas atividades humanas, associado à alteração da qualidade das águas por fontes poluidoras diversas, dentre elas as indústrias, tem comprometido de forma significativa o potencial de uso dos recursos hídricos, tornando-os escassos em muitas regiões ou requerendo maiores investimentos e novas tecnologias para a sua utilização. O entendimento deste cenário tem subsidiado a adoção de medidas que contemplam os preceitos da sustentabilidade, onde o uso racional e o reúso de águas aparecem como estratégias de grande relevância. Quanto ao reúso de águas, inclui-se a reutilização de efluentes, tratados ou não, para atendimento de usos menos restritivos, favorecendo a conservação da água, bem como preservando o recurso de melhor qualidade para os usos que as requerem. Desta forma, neste trabalho foi avaliada a viabilidade do reúso direto planejado de efluentes, originados em processos de galvanoplastia e submetidos ao tratamento complementar por membrana de osmose reversa, como insumo no processo produtivo de lavagem de peças. O estudo foi desenvolvido em uma indústria localizada em Botucatu, São Paulo, através da operação de uma unidade-piloto de osmose reversa de um estágio, com módulo de membrana tipo enrolada em espiral, sem recirculação. Durante o experimento, para avaliação do desempenho operacional do sistema e da eficiência de remoção de contaminantes, foram realizadas quatro campanhas de coletas, totalizando 173 amostras. O desempenho... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increase of water demand for the different human activities, associated to the quality deterioration by several pollution sources, among them, industries, has significantly been undermined the potential of water resources, making them scarce in many regions or requiring greater investments and new technologies for its use. The comprehension of this scenario has subsidized the adoption of measures to take account sustainability principles, where the rational use and reuse of water appear as high relevance strategy. About the water reuse, it includes the wastewater reuse, treated or not, to meet less restrictive uses, promoting the water conservation, as well as preserving the best quality resource for its intended uses. In this way, has been evaluated in this work the feasibility of the planned direct reuse of the wastewater, from electroplating process and submitted to complementary reverse osmosis treatment, used as an input in parts washing process. The study was developed in an industry located in Botucatu city, São Paulo, through the operation of a one-stage reverse osmosis pilot-unit with spiral-wound membrane module, without recirculation. Along the experiment, to assess the operational performance system and its contaminants removal efficiency as well, four collection campaigns were conducted, totaling 173 samples. Operational performance of the reverse osmosis was evaluated through the following variables: permeate flow, concentrate flow, permeate flux, recovery, ... (Complete abstract click electronic access below) / Mestre
88

Organic binder mediated Co3O4/TiO2 heterojunction formation for heterogeneous activation of Peroxymonosulfate

Kapinga, Sarah Kasangana January 2019 (has links)
Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2019. / A shortage of water has resulted in the need to enhance the quality of wastewater that is released into the environment. The advanced oxidation process (AOP) using heterogeneous catalysis is a promising treatment process for the management of wastewater containing recalcitrant pollutants as compared to conventional processes. As AOP is a reliable wastewater treatment process, it is expected to be a sustainable answer to the shortage of clean water. AOP using heterogeneous catalysis based on Co3O4 particles and PMS, in particular has been found to be a powerful procedure for the degradation and mineralization of recalcitrant organic contaminants. In addition, due to the growing application of Co3O4 in lithium batteries, large quantities of these particles will be recovered as waste from spent lithium batteries, so there is a need to find a use for them. Although this method has received some promising feedback, challenges still need to be addressed, such as the toxicity of cobalt particles, the poor chemical and thermal stability and particle aggregation, and the prompting of lower catalytic efficiency in long haul application. Furthermore, the removal of the catalyst after the treatment of pollutants is also an issue. In order to be applicable, a novel catalyst must be produced requiring the combination of Co3O4 with a support material in order to inhibit cobalt leaching and generate better particle stability. From the available literature, TiO2 was found to be the best support material because it not only provides a large surface area for well dispersed Co3O4, but it also forms strong Co-O-Ti bonds which greatly reduced cobalt leaching as compared to other support materials. Moreover, it also greatly encourages the formation of surface Co–OH complexes, which is considered a crucial step for PMS activation. Therefore, the issues cited above could be avoided by producing a Co3O4/TiO2 heterojunction catalyst.
89

Reúso de água: proposta principiológica para desenvolvimento de disciplina legal no Brasil / Reuse of water: proposal for development principled legal discipline in Brazil

Daniel Roberto Fink 06 February 2003 (has links)
A água é um bem essencial à vida. Por meio de sua utilização, a humanidade ao longo dos séculos vem desenvolvendo suas atividades econômicas, sociais e culturais. Mais recentemente a água se torna importante também para manutenção de ecossistemas e da vida, independentemente de estar ligada ao homem. Contudo, a água vem sofrendo duros golpes em sua qualidade e quantidade. O crescimento populacional desorganizado, provocando demandas crescentes por água potável e a poluição hídrica, são fatores que têm contribuído para sua escassez e piora de sua qualidade. A racionalização da utilização dos recursos naturais, passou a ser uma componente aguda na gestão ambiental e, em especial, dos recursos hídricos. Práticas ligadas à reutilização de recursos, como reciclagem de resíduos e reúso de água, cada vez mais ganham a pauta ambiental. O reúso de água se apresenta, assim, como alternativa para minorar a quantidade de água captada e minimizar o descarte de esgotos e efluentes. O reúso pode ocorrer nos vários usos múltiplos de recursos hídricos: abastecimento público, lazer, geração de energia, navegação, afastamento de esgotos, recarga de lençol freático, atividades esportivas, usos urbanos, agricultura e processos industriais. Há riscos na utilização de água de reúso. Há necessidade de regramentos para balizar esses usos e evitar efeitos negativos, em especial à saúde pública. O Direito positivo, por meio do exercício da competência legislativa do Estado, tem contribuição a dar no estabelecimento de regras condicionadoras do reúso. Essas regras devem, antes, estar baseadas em princípios capazes de orientar todo um conjunto de normas, gerais ou específicas, que venham num futuro regular o tema de reúso de água. presente trabalho pretende apontar alguns desses princípios. / Water is an essential asset. The human kind, using it during the last centuries, has been developing many economical, social and cultural activities. Nowadays, water has also become important for the maintenance of life and the ecosystems. 7 Connected or not to mankind. Water is undergoing severe damage, though. The unorganized population growth creates a crescent need for drinking water. On the other hand, the hidrical pollution caused by this uncontrolled growth has also contributed for the lack of amount and quality of the water. The rationalization of the usage of the natural resources has become an important component regarding environmental administration, specially the rationalization of hydrae resources. Practices such as the reutilization, recycling and the reuse of water are being more and more considered. The reuse of water itself is the alternative to reduce the amount of captured water and to minimize the dumping of sewer. The reuse may occur through many different hydria resources public supply, leisure, energy generation, navigation, shoving off the sewer, reloading the ground water, sports activities, urban usage, agricultural and industrial processes. There are some risks in working with the reuse of water, though. There is a need to create rules to establish this use and to avoid the negative effects it may cause, especially regarding the public health. The law, under the competence of the legislative state has to contribute to establish rules to regulate the reuse of water. These rules shall, above all, be based on principles which are capable to guide the whole set of principles, either specific or general, that might regulate the theme of water reuse in the near future. This is the purpose of this work.
90

Tecnologias de reúso aplicadas ao abastecimento de água potável e industrial da Baixada Santista / Reuse technologies applied to the drinking water and industrial supply of Baixada Santista

Santos, Carlos Lopes dos 22 December 1992 (has links)
Nesta tese, é apresentada uma revisão bibliográfica de reuso potável indireto e reuso industrial. Examina-se na prática dois estudos de caso, um de reuso industrial e um de reuso potável com aplicação para a Baixada Santista. O de reuso industrial refere-se ao projeto de fornecidmento de água oriunda da represa Billings, que com pequeno tratamento é oferecida às indústrias de Cubatão para fins não nobres como por exemplo, refrigeração, aquecimento a vapor, rega de jardins, abatimento de material particulado. etc. Quanto ao de reuso potável a apresentação se faz através de experimentos de laboratórios, examinando-se trihalometanos (THM) e o poder desinfetante de alguns produtos químicos após passagem da água por carvão ativado granular e outros tratamentos, e suas consequências na rede de abastecimento de água. Concluiu-se que o melhor ponto de instalação da captação para o abastecimento de água industrial fica entre os canais de fuga da usina Henry Borden, em Cubatão, por seu melhor desempenho econômico e pela possibilidade de atendimento no futuro a outras indústrias. Ainda, se comprovou a eficiência do carvão ativado granular na remoção dos precursores de THM e o baixo poder desinfetante da cloramina. / There is in this thesis, a small literature revision about the matter, mainly about indirect potable reuse and industrial reuse. In the practical part they are examined in two cases, industrial reuse and potable reuse, both for the Santos Basin. In the Industrial Reuse, there is a project to distribute industrial water to Cubatão industries, using water from Billings after a small treatment. This water is to be used in refrigeration of steel or to boil water to obtain steam or put in solid material to avoid air pollution, etc. In Potable Reuse, there are many laboratory experiences about THM and desinfection by many chemical products and their consequences in distribuition of water. In conclusion, the best place for ínstalation of the collection of water is located between the Henry Borden Power Plant Channels, in Cubatão, for it\'s superior economic performance and for the possibility to support other industries in the future. It has already confirmed the efficiency of the granular activated carbon to remove THM precursors and its inability to desinfect ammonia chlorine.

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