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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.
51

Management, disposal and recycling of waste organic solvents in Hong Kong /

Lau, Kin-wah. January 1998 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 106-111).
52

Logística de resíduos da construção civil atendendo à resolução CONAMA 307. / The logistic of construction waste according to CONAMA 307 resolution.

Ricardo Basile Pucci 18 May 2006 (has links)
O Resíduo de Construção e Demolição (RCD), devido ao seu volume, gera um alto impacto ambiental, social e econômico, trazendo assim a preocupação crescente sobre sua gestão. Essa gestão sempre foi responsabilidade do poder público. Porém, com a Resolução 307 do Conselho Nacional do Meio Ambiente (CONAMA), de 05 de julho de 2002, ela foi transferida para os geradores de resíduos, que devem segregar o resíduo em quatro classes diferentes e encaminhá-las para reciclagem ou deposição final. Assim, este trabalho propõe uma metodologia, baseada no enfoque sistêmico e em técnicas de pesquisa operacional, para tratar o problema de gestão de resíduos da Construção Civil, em conformidade com a Resolução CONAMA 307. A metodologia proposta compreende a elaboração de um Plano de Gestão de Resíduos que contemple a fase de projeto, minimizando a geração de resíduos; a segregação e o transporte do resíduo gerado dentro da obra; e a sua destinação final, incluíndo o controle da segregação e deposição do resíduo gerado. No trabalho são comparadas duas obras, uma onde não houve nenhuma forma de gestão sobre o resíduo e outra onde o Plano de Gestão proposto foi aplicado. Além disso, foi feito um modelo de simulação utilizando o programa de computador Arena 7.0, utilizado para avaliação do impacto do Plano em diversos cenários de geração, segrega ção e transporte dos resíduos. Como resultado do trabalho apresenta-se um Plano de Gestão de Resíduos que possui viabilidade econômica, social e ambiental, além de ser legalmente adequado, para ser usado por profissionais do setor público e privado no tratamento e gestão do resíduo gerado em suas obras. / The Construction and Demolition Waste (C&DW), because of its high volume, brings high environmental social and economical impacts, therefore the worries about its management has grown. This management has always been responsibility of the governments. But with the Resolution 307 of CONAMA (Brazilian Environmental National Council) of July 22nd, 2002, it was transferred to the waste producer, which has to segregate it in four different categories and ship it to be recycled or disposed properly. The proposal is to create a method, based on system approach and operations research, to deal with C&DW management, respecting Resolution 307 guidelines. The proposed method encompasses the creation of a Waste Management Plan, whichconsiders the aspects of the project, to minimize waste generation; the segregation and transport within the construction site; and the final destination of the waste, including a method to control its segregation and shipping. Two construction sites were considered, one that did not have any kind of waste management and one on which the Management Plan was implemented. In addition, it was developed a simulation model using the computer software Arena 7.0, to analyze the Plan under different scenarios of generation, segregation and shipping of construction waste. As a result, a Plan of C&DW Management was proposed and validated, which is economic, social and environmental feasible and legally adequate, to be used by public and private professionals when dealing with the C&DW of their constructions.
53

Gesso reciclado = avaliação de propriedades para uso em componentes / Recycled gypsum plaster : properties evaluation for components use

Pinheiro, Sayonara Maria de Moraes 12 May 2011 (has links)
Orientador: Gladis Camarini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-19T09:22:14Z (GMT). No. of bitstreams: 1 Pinheiro_SayonaraMariadeMoraes_D.pdf: 17416977 bytes, checksum: 40dd09aaf2b35647ee390d580feb5859 (MD5) Previous issue date: 2011 / Resumo: A busca pela viabilidade técnica e econômica da reciclagem de resíduos na cadeia produtiva da construção civil vem atender às novas necessidades do setor de promover um crescimento econômico integrado às necessidades sociais e ambientais. O gesso é um material construtivo de ampla aplicação no setor. O processo produtivo é relativamente simples e envolve baixo custo energético em relação a outros aglomerantes. A reversibilidade de suas reações de transformação possibilita a reciclagem do material, o que aumenta a possibilidade de reintegração no processo produtivo, minimizando os impactos ambientais de produção. As indústrias produtoras de componentes de gesso, na sua maioria, são formadas por empresas de pequeno porte, onde o resíduo gerado, na maioria das vezes, é disposto de forma irregular, sem controle e estimativa de volume. Esse resíduo é considerado pelas Resoluções 307/2002 e 431/2011 do CONAMA, como resíduo de Classe "B", resíduos recicláveis para outras destinações, sendo grande o seu potencial de reciclagem. As pesquisas científicas na área ainda são incipientes. Faz-se necessária uma investigação detalhada do resíduo e do material reciclado. Nesse sentido, o presente trabalho, por meio da adoção de um processo simples de reciclagem, composto das etapas de moagem e calcinação do resíduo de gesso de fundição, analisou as características químicas, microestruturais e as propriedades físicas e mecânicas dos gessos reciclados em ciclos consecutivos. Analisou também a influência do uso de aditivos nesses materiais. A análise dos resultados mostrou a viabilidade da reciclagem do resíduo de gesso e a necessidade de estudos mais específicos para que o gesso reciclado adquira o desempenho necessário para a aplicação no setor de componentes para a construção civil / Abstract: The search for technical and economical feasibility of waste recycling in the productive construction chain meets the new needs of the sector to promote an integrated development with economical, social and environmental needs. Gypsum plaster is a widely material used in civil construction. The productive process is relatively simple and it involves low energy costs compared to other binders. The reactions reversibility enables the recycling of the material, which increases the possibility of being reintegrated to the productive process as well as decrease environmental production impact. The gypsum components industries are formed by small companies, where the wastes are usually disposed incorrectly, without any control or estimate of volume. The waste is considered by Resolutions 307/2002 and 431/2011 from CONAMA as Class "B" which should be destined for recycling. Scientific research in this area is still incipient. It is necessary further investigations of this waste as a recycled material. In this way, the current research adopted a simple recycling process which produced a recycled gypsum plaster that was analyzed by its chemical and microstructures characteristics, as well as the physical and mechanical properties. The recycled plaster was obtained from consecutive cycles. The influence of using a superplasticizer in recycled plaster has been also analyzed. The results showed the feasibility to recycling the gypsum wastes, as well as the need of specific studies in order to allow the recycled gypsum plaster achieve the necessary performance to be applied for components in construction / Doutorado / Arquitetura e Construção / Doutor em Engenharia Civil
54

Materiály na bázi pěnového skla z druhotných surovin / Materials based on the foam glass of secondary raw materials

Hons, Oto January 2012 (has links)
In the theoretical part of diploma thesis basic knowledge about glass are given (materials, production process, a brief overview of glass products for construction industry) and statistics of waste production, primarily with an emphasis on various types of waste glasses were also mentioned. The following chapters of the thesis are focused on waste glass processing technologies. Various studies about the application of waste or recycled glass in manufacturing of building materials are summarized. In the practical part of diploma thesis were suggested appropriate secondary raw materials that were used to prepare materials based on thermally modified glass foam. In the practical part of the thesis was carried out a set of experiments and analysis, including evaluation in terms of the proposed alternative fillers and materials made of them.
55

Análisis de las propiedades mecánicas de los bloques de concreto de albañilería elaborados con partículas de vidrio y papel reciclado, Chota 2022

Gonzales Saldaña, Jordan Stuar January 2024 (has links)
El objetivo de la presente investigación es evaluar las propiedades mecánicas de los bloques de concreto de albañilería elaborados con partículas de vidrio y papel reciclado. Para ello, la muestra fue seleccionada de forma no probabilística por conveniencia, compuesta por 192 bloques de concretos fabricados con adiciones del 0%, 3%, 6%, y 9%. Los resultados obtenidos en absorción disminuyeron de 8.69% a 4,94%, 3,398% y 3,52% respectivamente. Sin embargo, el alabeo aumentó entre 1,7mm y 1,8mm, mientras que la resistencia a compresión (f'c) aumentó de 73Kg/cm2 a 75kg/cm2, 82kg/cm2 y 77kg/cm2, respectivamente. De manera similar, la resistencia a compresión axial (f'm) aumentó de 87.04Kg/cm2 a 91,22kg/cm2, 94,45kg/cm2 y 92,80kg/cm2, y la resistencia a compresión diagonal (V'm) aumentó de 8.43 Kg/cm2 a 8,90kg/cm2, 9,70kg/cm2 y 9,70kg/cm2. El costo de fabricación de las unidades de albañilería mostró una reducción progresiva de 0.60USD a 0,57USD, 0,55USD y 0,53USD costos de los bloques con adiciones. También se determinó que la adición óptima de estos materiales en la mezcla de concreto en términos de costo y resistencia es del 9% (vidrio + papel), resultando en resistencias a compresión de 77kg/cm2, 92.8kg/cm2 y compresión diagonal de 9.70kg/cm2, con un costo de 0.53USD por unidad. En conclusión, se puede asegurar que la adición de partículas de vidrio y papel reciclado en la producción de bloques de concreto influye positivamente en las propiedades físicas y mecánicas de los bloques. Además, permite una reducción de los costes de fabricación, lo que supone un importante ahorro para los constructores. / The objective of this research is to evaluate the mechanical properties of masonry concrete blocks made with glass particles and recycled paper. For this, the sample was selected in a non-probabilistic way for convenience, consisting of 192 concrete blocks manufactured with additions of 0%, 3%, 6%, and 9%. The results obtained in absorption decreased from 8.69% to 4.94%, 3.398% and 3.52% respectively. However, warpage increased between 1.7mm and 1.8mm, while compressive strength (f'c) increased from 73Kg/cm2 to 75kg/cm2, 82kg/cm2 and 77kg/cm2, respectively. Similarly, the axial compressive strength (f'm) increased from 87.04Kg/cm2 to 91.22kg/cm2, 94.45kg/cm2 and 92.80kg/cm2, and the diagonal compressive strength (V'm) increased from 8.43 Kg/cm2 to 8.90kg/cm2, 9.70kg/cm2 and 9.70kg/cm2. The manufacturing cost of the masonry units showed a progressive reduction from USD 0.60 to USD 0.57, USD 0.55 and USD 0.53 costs of the blocks with additions. It was also determined that the optimal addition of these materials in the concrete mix in terms of cost and resistance is 9% (glass + paper), resulting in compressive strengths of 77kg/cm2, 92.8kg/cm2 and diagonal compression of 9.70. kg/cm2, with a cost of 0.53USD per unit. In conclusion, it can be ensured that the addition of glass particles and recycled paper in the production of concrete blocks positively influences the physical and mechanical properties of the blocks. In addition, it allows a reduction in manufacturing costs, which represents significant savings for builders.
56

Acoustic and Thermal Properties of Recycled Porous Media

Mahasaranon, Sararat January 2011 (has links)
This thesis is concerned with developing porous materials from tyre shred residue and polyurethane binder for acoustic absorption and thermal insulation applications. The resultant materials contains a high proportion of open, interconnected cells that are able to absorb incident sound waves through viscous friction, inertia effects and thermal energy exchanges. The materials developed are also able to insulate against heat by suppressing the convection of heat and reduced conductivity of the fluid locked in the large proportion of close-cell pores. The acoustic absorption performance of a porous media is controlled by the number of open cells and pore size distribution. Therefore, this work also investigates the use of catalysts and surfactants to modify the pore structure and studies the influence of the various components in the chemical formulations used to produce these porous materials. An optimum type and amounts of catalyst are selected to obtain a high chemical conversion and a short expanding time for the bubble growth phase. The surfactant is used to reduce the surface tension and achieve a homogenous mixing between the solid particulates tyre shred residue, the water, the catalyst and the binder. It is found that all of the components significantly affect the resultant materials structure and its morphology. The results show that the catalyst has a particularly strong effect on the pore structure and the ensuing thermal and acoustical properties. In this research, the properties of the porous materials developed are characterized using standard experimental techniques and the acoustic and thermal insulation performance underpinned using theoretical models. The important observation from this research is that a new class of recycled materials with pore stratification has been developed. It is shown that the pore stratification can have a positive effect on the acoustic absorption in a broadband frequency range. The control of reaction time in the foaming process is a key function that leads to a gradual change in the pore size distribution, porosity, flow resistivity and tortuosity which vary as a function of sample depth. It is shown that the Pade approximation is a suitable model to study the acoustic behaviour of these materials. A good agreement between the measured data and the model was attained. / Ministry of Science and Technology of Thailand; Naresuan University, Phitsanulok, Thailand,
57

Resíduos de coco, acerola e caju para produção de carvão ativado

Ricardo Vandré Trótski Oliveira Silva 25 February 2015 (has links)
Com o crescimento das atividades industriais e da população, aumentam também a quantidade de resíduos gerados que ocasiona problemas ambientais. No Brasil, produtor de bens na agroindústria, os problemas causados pelo acúmulo e destinação inadequada dos resíduos sólidos é de grande porte. A partir dessa problemática são criados mecanismos que incentivam a reutilização e reciclagem dos resíduos. É buscando desenvolver tecnologia inédita de matérias-primas alternativas que se produziu carvão ativado a partir de resíduos de coco, acerola e caju. Primeiramente coletou-se a fibra-de-coco seco e bagaços/cascas de acerola e do caju para posterior preparação desse material através da impregnação com ZnCl2, da ativação química e da realização de um teste de avaliação da eficiência do carvão. Foi produzido carvão ativado com todas as amostras, onde a aplicação na amostra de água coletada no rio Capibaribe (perto do túnel Chico Science), Recife, Pernambuco, apresentou redução da turbidez em 97,3 % usando o tratamento com 25 % de fibra-de-coco + 75 % de caju. / With the growth of industrial activities and population, also increases the amount of generated waste which causes environmental problems. In Brazil, a major producer of goods in the agricultural industry, the problems caused by the accumulation and improper disposal of solid waste are large. From this problematic, mechanisms that encourage the reuse and recycling of waste are created. It is seeking to develop new technology of alternative raw materials that are produced activated carbon from coconut waste, barbados cherry and cashew. Primarily, the collection of fiber-to-dry coconut and cake/shells from barbados cherry and cashew for later preparation of this material by impregnation with ZnCl2, chemical activation and conducting an evaluation test coal efficiency. The result, within all samples, was an activated carbon where the application in the water sample collected from the Capibaribe River (near Chico Science tunnel), Recife, presented a decrease in turbidity in 97.3% using treatment with 25% fiber- coconut + 75% cashew.
58

Resíduos de coco, acerola e caju para produção de carvão ativado

Silva, Ricardo Vandré Trótski Oliveira 25 February 2015 (has links)
Made available in DSpace on 2017-06-01T18:20:45Z (GMT). No. of bitstreams: 1 ricardo_vandre_trotski_oliveira_silva.pdf: 610833 bytes, checksum: 744d83d7588313cd4ff2b78eb59399bf (MD5) Previous issue date: 2015-02-25 / With the growth of industrial activities and population, also increases the amount of generated waste which causes environmental problems. In Brazil, a major producer of goods in the agricultural industry, the problems caused by the accumulation and improper disposal of solid waste are large. From this problematic, mechanisms that encourage the reuse and recycling of waste are created. It is seeking to develop new technology of alternative raw materials that are produced activated carbon from coconut waste, barbados cherry and cashew. Primarily, the collection of fiber-to-dry coconut and cake/shells from barbados cherry and cashew for later preparation of this material by impregnation with ZnCl2, chemical activation and conducting an evaluation test coal efficiency. The result, within all samples, was an activated carbon where the application in the water sample collected from the Capibaribe River (near Chico Science tunnel), Recife, presented a decrease in turbidity in 97.3% using treatment with 25% fiber- coconut + 75% cashew. / Com o crescimento das atividades industriais e da população, aumentam também a quantidade de resíduos gerados que ocasiona problemas ambientais. No Brasil, produtor de bens na agroindústria, os problemas causados pelo acúmulo e destinação inadequada dos resíduos sólidos é de grande porte. A partir dessa problemática são criados mecanismos que incentivam a reutilização e reciclagem dos resíduos. É buscando desenvolver tecnologia inédita de matérias-primas alternativas que se produziu carvão ativado a partir de resíduos de coco, acerola e caju. Primeiramente coletou-se a fibra-de-coco seco e bagaços/cascas de acerola e do caju para posterior preparação desse material através da impregnação com ZnCl2, da ativação química e da realização de um teste de avaliação da eficiência do carvão. Foi produzido carvão ativado com todas as amostras, onde a aplicação na amostra de água coletada no rio Capibaribe (perto do túnel Chico Science), Recife, Pernambuco, apresentou redução da turbidez em 97,3 % usando o tratamento com 25 % de fibra-de-coco + 75 % de caju.
59

Automação de reator de hidrogênio para alimentação de motogerador em geração distribuida /

Junges, Rodrigo Santos January 2019 (has links)
Orientador: Dionízio Paschoareli Júnior / Resumo: Resumo / Doutor
60

Fertilidade do solo, nutrição e crescimento de plantas de eucalipto ao longo de 46 meses após aplicação de lodo de esgoto / Soil fertility, plant nutrition and growth of eucalyptus after 46 months of sewage sludge application

Maldonado, Carlos Alberto Baca 23 October 2009 (has links)
Objetivou-se avaliar o efeito da aplicação de lodo de esgoto, com ou sem adubo nitrogenado e, ou, fosfatado, sobre os atributos químicos do solo e o crescimento e nutrição de plantas de eucaliptos até aos 46 meses após aplicação do resíduo. Em dezembro de 2004 foi estabelecido um experimento de campo com quatro doses de lodo de esgoto (0; 7,7; 15,1 e 23,1 t ha-1, base seca, equivalentes a 0, 50, 100 e 150% do recomendado, com base no critério do N), nitrogênio (0; 46,9; 95,1 e 142 kg ha-1, equivalentes a 0, 33, 67 e 100% do N recomendado) e fósforo (0; 27,7; 53,6 e 84 kg ha-1, equivalentes a 0, 33, 67 e 100% do P2O5 recomendado), em esquema fatorial 4x4x4, com confundimento e duas repetições. Devido ao baixo teor de potássio no lodo, foi aplicado 188 kg ha-1 de K2O (100% do recomendado) em todas as parcelas. Foram realizadas coletas de solo aos 4, 14, 21 e 34 meses após a aplicação do lodo, nas camadas de 0-0,10; 0,10-0,20 e 0,20-0,40 m de profundidade, exceto aos 4 meses que foi feita até 90 cm de profundidade. Nas amostras coletadas aos 4 e aos 34 meses foram realizadas análises de pH em CaCl2, N-total, P (resina), Ca, Mg e K trocáveis, acidez total e matéria orgânica. Aos 14, 21 e 34 meses foram determinados o N-amoniacal e N-nitrato pelo método Kjeldahl. Teores extraíveis de Cu, Fe, Mn, Zn foram obtidos pelo método do DTPA e teores semitotais, por solubilização ácida (HNO3 + HCl), em forno microondas, sendo os elementos quantificados por espectrometria de massa com plasma (ICP-MS). Análises de amostras de folhas foram feitas aos 4 e 43 meses, de amostras de folhedo, trimestralmente e de amostras de serapilheira, aos 46 meses após aplicação do lodo, para determinar macro e micronutrientes. A decomposição do folhedo (método de bolsas de decomposição) foi avaliada aos 45, 90, 160, 230 e 300 dias. A altura e o diâmetro na altura do peito das árvores foram medidos aos 6, 9, 12, 18, 24, 33 e 44 meses após plantio, e, então, determinado o volume de madeira. Os resultados obtidos foram avaliados por modelos de superfície de respostas, em função das doses de lodo, nitrogênio e fósforo. As doses de lodo promoveram melhorias nos atributos de fertilidade do solo. Os teores de C-orgânico e de P, K, Ca e Mg trocáveis aumentaram na camada de 0 a 10 cm de profundidade. Os teores de Cu, Fe, Mn e Zn, extraíveis e semitotais, aumentaram nas camadas até 40 cm de profundidade. Os teores de C-orgânico aos 34 meses foram superiores aos teores obtidos aos 4 meses, enquanto que os valores de pH diminuíram. Os teores de N total e amoniacal aumentaram com as doses de lodo e de fertilizante nitrogenado, com maior acúmulo na camada de 0-10 cm. Não foi observado potencial de lixiviação de N-NO3-. As doses de lodo aumentaram os teores de N e de P nas folhas do eucalipto, assim como o adubo nitrogenado e fosfatado, respectivamente, mantendo teores adequados nas folhas recém-maduras do eucalipto. Os teores de Cu, Mn, Fe e Zn nas folhas de eucalipto foram aumentadas com as doses de lodo e se correlacionam com teores desses metais extraídos do solo com DTPA. O estudo de superfície de resposta, permitiu constatar que a aplicação de lodo, com base na dose recomendada pelo critério do N, pode propiciar a redução de 33% no uso do adubo fosfatado e 100% do adubo nitrogenado, sem prejuízos ao crescimento e à nutrição do eucalipto, com aumento da produtividade de madeira / This study aimed to evaluate the effect of sewage sludge, with or without mineral nitrogen and phosphate fertilizer on the soil chemical properties, nutrition and growth of Eucalyptus plants up to 46 months after sewage sludge application. Therefore, in December 2004 was established a field experiment with four doses of sewage sludge (0, 7.7, 15.1 and 23.1 t ha-1, dry base), N (0, 46.9; 95.1 and 142 kg ha 1) and phosphorus (0, 27.7, 53.6 and 84 kg ha-1 P2O5), in a randomized block design in factorial design 4x4x4 with two repetitions. Due to low content of potassium (K) in the sewage sludge was applied 188 kg ha-1 K2O in all plots. Samples of soil were collected at 4, 14, 21 and 34 months after sludge application, from the 0-0.10, 0.10-0.20 and 0.20-0.40 m layers, except at 4 months which was made up to 0.90 m depth. Samples collected at 4 and 34 months were analyzed for pH in CaCl2 0.01 mol L-1, total N, available P (resin), Ca, Mg and K contents, total acidity and organic matter. At 14, 21 and 34 months were determined ammonia-N and nitrate-N by the Kjeldahl method. Extractable Cu, Fe, Mn and Zn were obtained using the DTPA solution, and semi-total levels dissolution by acid (HNO3 + HCl), in a microwave oven, and analyzed by ICP-MS (inductively coupled plasma mass spectrometer. Analysis of leaf samples were made at 4 and 43 months, samples of leaf litter, quarterly and litter at 46 months after sludge application, to determine macro and micronutrients. The decomposition of leaf litter (method of decomposition bags) was evaluated at 45, 90, 160, 230 and 300 days. The height and diameter at breast height (DBH) of trees were measured at 6, 9, 12, 18, 24, 33 and 44 months after planting, and then determined the volume of wood. The results were evaluated by surface models of responses, depending on the sludge doses, nitrogen and phosphorus. The growth of the plants was adjusted by growth curves. The sludge application promoted improvements in the attributes of soil fertility. The content of organic C and P, K, Ca and Mg increased in the 0 to 10 cm depth. The contents of Cu, Fe, Mn and Zn, extractable and semitotals increased in layers up to 40 cm depth. The levels of organic C to 34 months were higher than levels found at 4 months, while the pH decreased. The levels of total N and ammonia increased with doses of sludge and fertilizer, with higher accumulation at 0-10 cm. There was no potential leaching of N-NO3-. Both the sludge as fertilizer applied increases the levels of N and P of eucalyptus leaves, maintaining appropriate levels in recently matured leaves. The Cu, Mn, Fe and Zn in eucalyptus leaves were increased with sludge doses and are correlated with concentrations of DTPA metals extracted from soil. The response surfaces study, allowed to prove that the application of sludge, based on the recommended dose by the N criterion, can provide a 33% reduction in the phosphate fertilizer and 100% of nitrogen fertilizer, without damage to the eucalyptus nutrition and growth, with increase wood productivity.

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