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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.
1

Impact of recirculation on landfill leachate quality

Ochieng' Otieno, Frederick A. January 1989 (has links)
No description available.
2

The Evolution of a Municipal Solid Waste Disposal System: A Design Case Study

Love, Osborne Raymond 07 1900 (has links)
A record of the design evaluation of a municipal solid waste disposal system has been made. The record was arranged chronologically on a process basis. The author had presented his analyses of the design influences. Emphasis has been put on the major influences. Observations and analyses of a more general nature, plus personal views of the case study method are also given. Recommendations for further study of this project are provided in a test proposal outline for the system. / Thesis / Master of Engineering (ME)
3

Characterizing the Municipal Solid Waste Stream in Denton, Texas

Brady, Patricia D. 08 1900 (has links)
Forty-two commercially collected dumpsters from Denton’s Municipal Solid Waste Stream were emptied, sorted and weighed to characterize the material types and make preliminary recycling policy recommendations. The general composition of Denton’s solid waste stream was not significantly different from the composition of the nation’s solid waste stream. Fifty-eight percent of the observed waste stream was recyclable. Paper made up the largest portion of recyclable materials and the "grocery" source category had more paper than any of the other five categories. Based on these findings, an incrementally aggressive approach is recommended to reduce certain types of wastes observed in the waste stream. This would include a Pay-As-You-Throw Program followed by an Intermediate Processing Center that can be converted to a Materials Recovery Facility.
4

Application of Stochastic Decision Models to Solid Waste Management

Wright, William Ervin 08 1900 (has links)
This research applies stochastic decision tree analytical techniques to a decision of the type a small community may face when choosing a solid waste disposal system from among several alternatives. Specifically targeted are those situations in which a community finds itself (1) lying at or near the boundary of a central planning area, (2) in a position to exercise one of several disposal options, and (3) has access to the data base on solid waste which has been systematically developed by a central planning agency. The options available may or may not be optimal in terms of total cost, either to the community or to adjacent communities which participate in centrally coordinated or jointly organized activities. The study suggests that stochastic simulation models, drawing upon a data base developed by central planning agencies in cases where local data are inadequate or not available, can be useful in evaluating disposal alternatives at the community level. Further, the decision tree can be usefully employed to communicate results of the analysis. Some important areas of further research on the small community disposal system selection problem are noted.
5

The effect of corporate environmental investments on shareholder value in selected JSE SRI listed mining companies

Chitepo, Kevin Tinashe January 2017 (has links)
Thesis (M.COM. (Accounting)) -- University of Limpopo, 2017 / Corporate environmental investments have traditionally been deemed to be an unnecessary cost to companies because of perceived or no significant return on investment. However, recent literature is highlighting financial benefits accruing from environmental investments. This study investigates the relationship between corporate environmental investment and shareholder value. The study uses the stakeholder and legitimacy theory to define the company‟s engagement with its external society and environment. From that perspective, the study examines the effect of corporate environmental investment on carbon emissions, hazardous solid waste disposal and company share price. Panel data multiple regression was used to investigate the relationship between the variables under study. Findings show a significant positive relationship between investment in carbon emissions and share price while there is an insignificant negative relationship between investment in hazardous solid waste and share price. The study contributes to the notion that reducing the environmental footprint generates positive shareholder gains by bringing new evidence from the South African mining industry. Further studies can be performed with company profitability as a measure of financial performance and further in a different sector such as manufacturing.
6

Reservoir screening criteria for deep slurry injection

Nadeem, Muhammad January 2005 (has links)
Deep slurry injection is a process of solid waste disposal that involves grinding the solid waste to a relatively fine-grained consistency, mixing the ground waste with water and/or other liquids to form slurry, and disposing of the slurry by pumping it down a well at a high enough pressure that fractures are created within the target formation. This thesis describes the site assessment criteria involved in selecting a suitable target reservoir for deep slurry injection. The main goals of this study are the follows: <ul> <li>Identify the geological parameters important for a prospective injection site</li> <li>Recognize the role of each parameter</li> <li>Determine the relationships among different parameters</li> <li>Design and develop a model which can assemble all the parameters into a semi-quantitative evaluation process that could allow site ranking and elimination of sites that are not suitable</li> <li>Evaluate the model against several real slurry injection cases and several prospective cases where slurry injection may take place in future</li> </ul> The quantitative and qualitative parameters that are recognized as important for making a decision regarding a target reservoir for deep slurry injection operations are permeability, porosity, depth, areal extent, thickness, mechanical strength, and compressibility of a reservoir; thickness and flow properties of the cap rock; geographical distance between an injection well and a waste source or collection centre; and, regional and detailed structural and tectonic setup of an area. Additional factors affecting the security level of a site include the details of the lithostratigraphic column overlying the target reservoir and the presence of overlying fracture blunting horizons. Each parameter is discussed in detail to determine its role in site assessment and also its relationship with other parameters. A geological assessment model is developed and is divided into two components; a decision tree and a numerical calculation system. The decision tree deals with the most critical parameters, those that render a site unsuitable or suitable, but of unspecified quality. The numerical calculation gives a score to a prospective injection site based on the rank numbers and weighting factors for the various parameters. The score for a particular site shows its favourability for the injection operation, and allows a direct comparison with other available sites. Three categories have been defined for this purpose, i. e. average, below average, and above average. A score range of 85 to 99 of 125 places a site in the ?average? category; a site will be unsuitable for injection if it belongs to the ?below average? category, i. e. if the total score is less than 85, and the best sites will generally have scores that are in the ?above average? category, with a score of 100 or higher. One may assume that for sites that fall in the ?average? category there will have to be more detailed tests and assessments. The geological assessment model is evaluated using original geological data from North America and Indonesia for sites that already have undergone deep slurry injection operations and also for some possible prospective sites. The results obtained from the model are satisfactory as they are in agreement with the empirical observations. Areas for future work consist of the writing of a computer program for the geological model, and further evaluation of the model using original data from more areas representing more diverse geology from around the world.
7

Avaliação do risco à saúde da população vizinha às áreas de disposição final de resíduos sólidos urbanos: o aterro sanitário como cenário de exposição ambiental / Health risk assessment to population who lives near a municipal solid waste disposal site: the landfill as the environmental exposure scenery

Azevedo, Mônica de Abreu 16 January 2004 (has links)
O presente estudo visou ao desenvolvimento de um estudo epidemiológico do tipo transversal para a avaliação do risco para a saúde da população residente próxima a uma área de disposição final de resíduos sólidos urbanos. O levantamento dos dados foi realizado no bairro de Perus, na cidade de São Paulo, SP, vizinho ao aterro sanitário Bandeirantes. O aterro Bandeirantes recebe diariamente cerca de 6.000 toneladas de resíduos sólidos do tipo Classe II e III. O aterro ocupa uma área total de 1.400.000 m2, contendo aproximadamente 33 milhões de toneladas de resíduos dispostos. Os riscos para a saúde pública foram avaliados junto à população de estudo, 972 crianças na faixa etária de 1 a 5 anos incompletos, residente próxima ao aterro Bandeirantes. A área de estudo foi dividida em faixas distantes de 500 m do limite do aterro, para a definição das condições de exposição. Os indicadores de saúde utilizados foram: as prevalências de enfermidades diarréicas e parasitárias e os índices antropométricos. Na área de estudo, foi realizado um levantamento da qualidade ambiental, com intuito de relacionar os impactos ambientais, ocasionados pela prática de disposição final considerada, aos indicadores de saúde empregados. Os resultados obtidos, pela realização deste estudo, permitiram concluir que há relações estatisticamente significativas entre as exposições pesquisadas e os indicadores de saúde empregados. / This work had the objective to develop an epidemiological study, using a transversal design, to evaluate the health risk to people who lives near a municipal solid waste disposal site. The study was accomplished at bairro de Perus, in the city of São Paulo - SP, Brazil, near to the Bandeirantes landfill site. The Bandeirantes landfill receives daily around 6,000 tons of Class II and III solid waste types. The landfill occupies a total area of 1,400,000 m2, containing around 33 millions of tons of disposed waste. The public health risks were evaluated among 972 children, of one to five years old, who live near the Bandeirantes landfill. The studied area was divided in distant lines of 500 meter from the landfill limit to define the exposure conditions. The used health indicators were: diarrhoeal, intestinal parasite prevalence and nutritional status. In the studied area, an environmental quality survey was accomplished with the intentions of relating the environmental impacts occasioned by the solid waste disposal to the used health indicators. The obtained results made it clear to conclude that the there are statistical associations between the researches environmental exposures and the used health indicators.
8

Reservoir screening criteria for deep slurry injection

Nadeem, Muhammad January 2005 (has links)
Deep slurry injection is a process of solid waste disposal that involves grinding the solid waste to a relatively fine-grained consistency, mixing the ground waste with water and/or other liquids to form slurry, and disposing of the slurry by pumping it down a well at a high enough pressure that fractures are created within the target formation. This thesis describes the site assessment criteria involved in selecting a suitable target reservoir for deep slurry injection. The main goals of this study are the follows: <ul> <li>Identify the geological parameters important for a prospective injection site</li> <li>Recognize the role of each parameter</li> <li>Determine the relationships among different parameters</li> <li>Design and develop a model which can assemble all the parameters into a semi-quantitative evaluation process that could allow site ranking and elimination of sites that are not suitable</li> <li>Evaluate the model against several real slurry injection cases and several prospective cases where slurry injection may take place in future</li> </ul> The quantitative and qualitative parameters that are recognized as important for making a decision regarding a target reservoir for deep slurry injection operations are permeability, porosity, depth, areal extent, thickness, mechanical strength, and compressibility of a reservoir; thickness and flow properties of the cap rock; geographical distance between an injection well and a waste source or collection centre; and, regional and detailed structural and tectonic setup of an area. Additional factors affecting the security level of a site include the details of the lithostratigraphic column overlying the target reservoir and the presence of overlying fracture blunting horizons. Each parameter is discussed in detail to determine its role in site assessment and also its relationship with other parameters. A geological assessment model is developed and is divided into two components; a decision tree and a numerical calculation system. The decision tree deals with the most critical parameters, those that render a site unsuitable or suitable, but of unspecified quality. The numerical calculation gives a score to a prospective injection site based on the rank numbers and weighting factors for the various parameters. The score for a particular site shows its favourability for the injection operation, and allows a direct comparison with other available sites. Three categories have been defined for this purpose, i. e. average, below average, and above average. A score range of 85 to 99 of 125 places a site in the ?average? category; a site will be unsuitable for injection if it belongs to the ?below average? category, i. e. if the total score is less than 85, and the best sites will generally have scores that are in the ?above average? category, with a score of 100 or higher. One may assume that for sites that fall in the ?average? category there will have to be more detailed tests and assessments. The geological assessment model is evaluated using original geological data from North America and Indonesia for sites that already have undergone deep slurry injection operations and also for some possible prospective sites. The results obtained from the model are satisfactory as they are in agreement with the empirical observations. Areas for future work consist of the writing of a computer program for the geological model, and further evaluation of the model using original data from more areas representing more diverse geology from around the world.
9

Análise das estimativas de emissão de metano por aterros sanitários em projetos de MDL no Brasil. / Analysis of the methane emissions estimation by Solid Waste Disposal Sites in Brazilian CDM projects.

Thiago Augusto Pimenta Viana 05 April 2012 (has links)
Para a maioria dos municípios brasileiros, a instalação de um aterro sanitário é um desafio, sendo uma das dificuldades o custo elevado. Existem algumas formas de mitigar estes custos e uma delas é através do mercado de emissões. Com planejamento prévio suficiente, é possível queimar o metano gerado através da degradação do resíduo, podendo resultar em benefícios para o aterro tanto através do aproveitamento (geração de energia ou venda direta) quanto recebimento de algum tipo de certificado de emissões negociável. Incluído neste planejamento prévio suficiente está a realização da estimativa ex-ante de emissão de metano para saber previamente qual será o aproveitamento mais indicado e a eventual receita oriunda da queima. Quando analisados os projetos de MDL feitos em aterros sanitários, pode ser notado que estas estimativas são muitas vezes mal feitas, gerando valores estimados muito acima do realmente observado durante a operação. Este erro acarreta uma perda de credibilidade deste tipo de projeto, já que o número esperado é raramente alcançado. Existem alguns fatores que contribuem para esta discrepância de valores, sendo problemas operacionais (como exemplo podem ser citados deficiência no sistema de captura do biogás e problemas na captação e recirculação de lixiviado) e de modelagem (utilização de valores de entrada experimentais obtidos sob situações muito diferentes das encontradas nos aterros brasileiros, por exemplo) os possíveis principais vilões. Este trabalho visa apresentar e discutir os principais problemas na realização de estimativas prévias de emissão de metano em aterros sanitários utilizando projetos brasileiros de MDL registrados e que estejam atualmente emitindo créditos de carbono como base para analisar a qualidade das estimativas feitas atualmente. Além disto, busca-se também entrevistar profissionais da área para tentar obter diferentes pontos de vista sobre esta questão. Fica claro que os valores estimados, de um modo geral, são entre 40 e 50% superiores aos observados. Metade dos especialistas aponta problemas operacionais diversos como os principais contribuintes desta diferença, mas problemas na modelagem parecem influenciar decisivamente na realização das estimativas. A utilização de valores de entrada no modelo precisa ser criteriosamente analisada e devem ser utilizados números obtidos através de pesquisas que representem a realidade do aterro em questão. / Most of the Brazilian municipalities find the installation of a Solid Waste Disposal Site a challenge due to the high investment needed. There are some ways to mitigate these costs, including emissions trading. With previous planning, it is possible to burn the methane produced by the decomposition of the waste, resulting in benefits for the landfill by either the simple use of the gas (generating electricity or directly selling the gas) or the revenues from negotiations of emissions certificates. Included in previous planning is the ex-ante estimation of the methane produced by the landfill in order to know beforehand how to make the best use of the biogas and the amount of revenues that can be obtained from this use. When the CDM projects developed in landfills are analyzed, it can be noticed that these estimations generally are poorly made, resulting in estimated values far above the real methane production. This mistake results in a credibility loss by this type of project, since the expected number is rarely achieved. There are some factors that contribute to this difference in values, being operational problems (such as deficiency in the biogas capture and problems in the collection and recirculation of the leachate) and modeling problems (such as the use of input values obtained from experiments in laboratories under different situations from the ones found in Brazilian landfills) the major issues. The present work aims to present and discuss the main problems in estimating ex-ante the methane produced by landfills, using Brazilian CDM projects that are registered and issuing carbon credits as sources to analyze the quality of estimations currently being made. Additionally, experts in landfills and estimations are interviewed in order to obtain different points of view. It is clear that the estimated values, in general, are between 40 and 50% higher than observed during the operation of the landfill. Half of the experts point operational problems as the main contributors, however modeling problems seems to have a decisive influence in estimations. The use of input values must be carefully analyzed and must be used numbers obtained through researches that represent the reality of the landfill in question.
10

O desafio do gerenciamento dos resíduos sólidos industriais no Rio Grande do Sul frente à legislação ambiental : um estudo para o setor metalmecânico

Cavalli, Cléo January 2015 (has links)
O presente trabalho se propôs a analisar um conjunto de empresas do setor metalmecânico, de maneira a verificar possíveis variações no cenário da disposição final dos Resíduos Sólidos Industriais (RSI) após a publicação da Política Nacional de Resíduos Sólidos (PNRS). Foram entrevistadas 22 empresas do setor metalmecânico e 6 Aterros e Centrais de Disposição Final, todas com localização no estado do Rio Grande do Sul. A seleção das empresas deu-se através do estabelecimento de alguns critérios, e estas foram subdividas em 3 amostras: Amostra A (empresas do setor metalmecânico que deixaram de enviar RSI para disposição final antes de 2010), Amostra B (empresas do setor metalmecânico que deixaram de enviar RSI para disposição final no período entre os anos de 2010 e 2014, ou que ainda continuam destinando resíduos para disposição final até a data da pesquisa) e Amostra C (aterros e centrais de disposição final). O procedimento metodológico consistiu na aplicação de um instrumento de coleta de dados através de entrevistas presenciais ou por telefone com profissionais da área ambiental de cada empresa. Os dados foram coletados entre os meses de outubro/2014 a abril/2015 e limitaram-se ao período entre os anos de 2010 a 2014. Os resultados estão apresentados em dois capítulos, sendo que o primeiro refere-se a uma análise global segmentado por amostra de empresa, e o segundo é dedicado às empresas da Amostra B. Os principais resultados encontrados nas empresas da Amostra B apontam reduções no envio dos RSI para disposição final, principalmente dos resíduos classe I, e pode-se verificar um aumento de envio dos classe II. Na Amostra C foi possível verificar uma expressiva diminuição no recebimento dos resíduos classe I e por outro lado, aumento dos resíduos classe II, até o ano de 2013. Os principais fatos que justificam este cenário de disposição final no Estado, referem-se a publicações legais, como a Portaria nº 16 da FEPAM/RS que proíbe o envio de resíduos com características de inflamabilidade para disposição final e também a preocupação com a não geração de passivos ambientais. / The purpose of this study was to analyze the possible variations on the of Industrial Solid Waste (ISW) disposal scenario from metal-mechanic companies after the publication of the National Solid Waste Policy (NSWP). 22 companies from metal-mechanic sector and 6 landfills/final disposal plants were interviewed, all those in the state of Rio Grande do Sul - Brazil. Criteria were established for companies selection in which have been subdivided into three samples: Sample A (metal-mechanic companies that stopped sending ISW before 2010), Sample B (metal-mechanic companies stopped sending ISW in the period between 2010 and 2014, or that are still sending waste for disposal until the date of the survey) and Sample C (landfills and final disposal plants). The used methodology was the application of a survey instrument through professional interviews or by telephone in the environmental departments of each company. Data were collected between the months of 2014, October to 2015, April and limited to the period of 2010 to 2014. The presented results are in two chapters. The first relates to a comprehensive analysis segmented by each company of the sample, and the second is dedicated to the Sample B companies. The main results in Sample B companies indicate ISW shipping reductions for disposal, mainly of the hazardous waste, and there is a increasing shipment of non-hazardous waste. In the Sample C was verified a significant decreasing in the receipt of hazardous waste and, in the other hand, a increasing of non-hazardous waste by the year 2013. The main facts which justify this disposal scenario in the state, refers to the legal publications, like FEPAM/RS no 16 Administrative Rule that prohibits the flammability waste disposal as well the concern about environmental liabilities non generation.

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