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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.
31

Environmental Systems Analysis Tools as Decision-Support in Municipal Solid Waste Management : LCA in Sweden, Estonia and Lithuania

Johnson, Amanda January 2013 (has links)
In order to deal with the mounting issue of Municipal Solid Waste (MSW) in a way that is in line with sustainable development and Integrated Solid Waste Management (ISWM) a systems approach is necessary.This approach can practically be integrated into the MSW decision-making process through Life Cycle Thinking(LCT) and environmental systems analysis tools such as Life Cycle Assessment (LCA). This paper is written within the context of the RECO Baltic 21 Tech (RB21T) project which aims to improve waste management practices in 12 countries in the Baltic Sea Region. The main aim of this paper is to investigate the extent to which LCA is used as decision-support in MSW management in Sweden, Estonia and Lithuania. The use of LCA is examined on a national level as well as on a local or regional level based on relevant literature and a set of interviews conducted in each country. According to the results the use of LCA as decision-support in MSW management is very limited in Estonia and Lithuania whilst it is already a well-established tool in Sweden. Most of the LCA efforts in the Baltic States have been conducted in connection with foreign projects and investments,such as RB21T. Although an actual LCA might not always be applied in Sweden, LCT is prevalent in MSW management both on a national and local level. In order for LCA to be better integrated into MSW management this paper argues that there is a need for increased knowledge, data, more user-friendly LCA-tools andstrengthening regional partnerships for further transfer of knowledge between countries.
32

The Analysis of PCDD and PCDF Emissions from the Cofiring of Densified Refuse Derived Fuel and Coal

Moore, Paul, 1962- 08 1900 (has links)
The United States leads the world in per capita production of Municipal Solid Waste (MSW), generating approximately 200 million tons per year. By 2000 A.D. the US EPA predicts a 20% rise in these numbers. Currently the major strategies of MSW disposal are (i) landfill and (ii) incineration. The amount of landfill space in the US is on a rapid decline. There are -10,000 landfill sites in the country, of which only 65-70% are still in use. The Office of Technology Assessment (OTA) predicts an 80% landfill closure rate in the next 20 years. The development of a viable energy resource from MSW, in the form of densified Refuse Derived Fuel (dRDF), provides solutions to the problems of MSW generation and fossil fuel depletions. Every 2 tons of MSW yields approximately 1 ton of dRDF. Each ton of dRDF has an energy equivalent of more than two barrels of oil. At current production rates the US is "throwing away" over 200,000,000 barrels of oil a year. In order to be considered a truly viable product dRDF must be extensively studied; in terms of it's cost of production, it's combustion properties, and it's potential for environmental pollution. In 1987 a research team from the University of North Texas, in conjunction with the US DOE and Argonne National Laboratory (ANL), cofired over 550 tons of dRDF and bdRDF with a high sulfur Kentucky coal in a boiler at ANL. This work examines the emission rates of polychlorinated dioxins (PCDDs) and furans (PCDFs) during the combustion of the dRDF, bdRDF, and coal. Even at levels of 50% by Btu content of dRDF in the fuel feedstock, emission rates of PCDDs and PCDFs were below detection limits. The dRDF is shown to be an environmentally acceptable product, which could help resolve one of the major social and environmental problems facing this country today.
33

Manufacturer [Sic] of Densified-Refuse Derived Fuel (d-RDF) Pellets and Methods for the Determination of d-RDF Pellet Densities

Attili, Bassam Saleem 12 1900 (has links)
There are 150 million tons of Municipal Solid Waste (MSW) annually produced in the United States, which is approximately equivalent to 150 million barrels of oil. MSW production is inexhaustible, and is increasing on an annual per capita basis of approximately three per cent. After controlling the moisture and adding a binder, the combustible portion of MSW was converted to pellets. The objects of this project were to 1) evaluate the binder, 2) prepare the pellets, and 3) evaluate the pellets with regard to density. The manufacture of pellets was conducted at the Naval Air Station, Jacksonville, Florida. The evaluation of the binders and the pellets was done at North Texas State University (NTSU). There were three procedures for measuring the density. The first, using water displacement, was from the American Society for Testing and Material (ASTM). The second, using wax coating, was also from ASTM. The third, using sharply-cut cylindrical pellets, was developed at NTSU.
34

Diagnóstico e sistematização de estratégias para a gestão dos resíduos domiciliares aplicáveis a políticas de planejamento urbano. / Diagnosis and systematization of strategies for the management of household waste applicable to urban planning policies.

Tierno, Ricardo 04 April 2017 (has links)
No início deste século são inúmeros os desafios que tangem à gestão dos resíduos sólidos urbanos nos municípios brasileiros. Os índices de geração aumentam a cada ano, os serviços de coleta e transporte não são universalizados, os índices de tratamento e valorização ainda são incipientes e muitos municípios utilizam formas ambientalmente inadequadas para a disposição final dos resíduos sólidos, mesmo depois do Decreto Federal nº 7.404/2010, que regulamentou a Política Nacional dos Resíduos Sólidos. As cidades, como principais polos atratores do consumo de insumos e geradores de resíduos sólidos urbanos, constituem, por sua vez, o ambiente principal onde se realiza grande parte das atividades inerentes ao gerenciamento de resíduos sólidos. Portanto, as condições de desenvolvimento urbano, estabelecidas pelas políticas urbanas e seus instrumentos, influenciam diretamente na qualidade, desempenho e eficiência do gerenciamento de resíduos sólidos, principalmente daqueles de origem domiciliar. O objetivo principal deste estudo foi desenvolver uma abordagem integrada entre o planejamento urbano e os serviços de gerenciamento de resíduos domiciliares, investigando e analisando elementos e aspectos comuns, para propor estratégias sistematizadas no âmbito dos instrumentos urbanísticos, com vistas à eficientização e qualificação desses serviços e dos espaços urbanos utilizados. Após realizar a caracterização das etapas do gerenciamento dos resíduos sólidos urbanos, identificou-se oito estratégias que poderiam ser introduzidas no âmbito do planejamento urbano. Em seguida, procedeu-se a um estudo de caso, uma área urbana sujeita à adensamento populacional e verticalização, localizada no bairro do Belenzinho, zona leste do município de São Paulo, onde, por meio da construção de cenários, simulou-se a aplicação das estratégias de planejamento urbano. Por fim, pode-se concluir que, em função das estratégias propostas, seria possível alcançar benefícios em relação à gestão dos resíduos domiciliares, justificando, portanto, a aplicabilidade dessas diretrizes em políticas de planejamento urbano aplicáveis a situações urbanas similares. / There are, today, numerous challenges regarding the management of solid waste in Brazilian cities. Regarding household waste, which is the subject of this study, generation rates increase each year, collection and transportation services are not universalized, treatment and valuation rates are still incipient, and many cities use environmentally inappropriate forms for final disposal of the waste, even after Federal Decree No. 7,404 / 2010, which regulated the National Policy on Solid Waste, established by Federal Law No. 12,305 of August 2, 2010. Cities, as the main poles attracting consumption of inputs and generators of solid waste of household origin, constitute the main environment where great parts of the solid waste management activities are carried out. Therefore, urban development conditions, established by urban policies and their instruments, directly influence the quality, performance and efficiency of waste management. The main objective of this study was to develop an integrated approach between urban planning and solid waste management services, investigating and analyzing common elements and aspects, proposing systematized strategies within urban planning instruments, with a view to the efficiency and qualification of these services and urban spaces used. After characterizing the stages of urban solid waste management, eight (8) strategies were identified that could be introduced in urban planning. The next step refers to a case study that took place in an urban area with population densification and verticalization, located in the neighborhood of \"Belenzinho\", in the eastern zone of the city of São Paulo, where urban planning strategies were simulated through the construction of specific scenarios. Finally, we can conclude that, according to the proposed strategies, it would be possible to achieve benefits regarding the management of household waste to justify the applicability of these strategies in urban planning policies applicable to similar urban situations.
35

Análise de sistemas de gestão de resíduos sólidos urbanos em municípios a partir da experiência das cidades de São Leopoldo/Brasil e Zurique/Suíça

Ghesla, Pamela Lisie 27 February 2012 (has links)
Submitted by CARLA MARIA GOULART DE MORAES (carlagm) on 2015-04-06T18:51:25Z No. of bitstreams: 1 PamelaLisieGhesla.pdf: 3329936 bytes, checksum: e4b91de032281838a99464b512fd963a (MD5) / Made available in DSpace on 2015-04-06T18:51:25Z (GMT). No. of bitstreams: 1 PamelaLisieGhesla.pdf: 3329936 bytes, checksum: e4b91de032281838a99464b512fd963a (MD5) Previous issue date: 2012-02-27 / UNISINOS - Universidade do Vale do Rio dos Sinos / Banco Santander / Banespa / O papel das administrações municipais na gestão dos resíduos sólidos gerados pelas comunidades tem se mostrado complexo e muitas vezes ineficiente, em razão da execução dos serviços de maneira emergencial e constantes mudanças em sua estrutura. Ciente das dificuldades do poder público em realizar a gestão de forma a atender os aspectos técnicos, ambientais e financeiros, o presente trabalho baseou-se no estudo de caso de São Leopoldo (Brasil) e Zurique (Suíça). O objetivo foi analisar a gestão dos resíduos sólidos urbanos nas duas cidades, propondo ações de intervenção e que auxiliem os gestores em suas decisões. Através das informações coletadas em entrevistas aplicadas aos órgãos responsáveis de cada cidade, foram caracterizadas as operações gerenciais, sendo criado um Mapeamento de Fluxo de Resíduos para visualização dos dados e comparação dos sistemas. Foi possível perceber que, apesar de São Leopoldo e Zurique possuírem semelhança em área territorial, executam a gestão de seus resíduos de formas distintas. Constatou-se positivamente que os dois municípios possuem coleta seletiva e destinam adequadamente seus resíduos, porém a qualidade dos processos em São Leopoldo é inferior a Zurique, acarretando em menor volume de materiais reinseridos na cadeia de produção e aumentando o volume de resíduos enviado ao aterro sanitário. Em contrapartida, o modelo de gestão de Zurique é mais oneroso, principalmente em relação à incineração, mas seu sistema de cobrança e comercialização de energia acaba envolvendo mais a população e custeando as operações. A pesquisa revelou pontos que podem ser melhorados nas duas cidades, o que pode servir futuramente de base de informações para outros municípios. Também auxiliou no entendimento de que cada etapa gerencial possui suas particularidades, que devem ser planejadas e controladas, pois a qualidade final da gestão é alcançada com base no somatório de todas as operações. / The role of municipalities in the solid waste management currently generated by the communities, has proved complex and often inefficient when the chosen model is executed in an emergency way or when constant changes happen. Aware about the difficulties faced by municipalities in implement the management attending the technical, environmental and financial features, this paper was based on a case study of Sao Leopoldo (Brazil) and Zurich (Switzerland). The objective was to analyze the municipal solid waste management in the two cities, proposing actions and interventions that assist managers in their decisions. Using the informations collected in interviews applied to responsible agencies, each operational step was characterized, was also created a Waste Stream Mapping for data visualization and comparison of systems. The results allowed seeing even that Sao Leopoldo and Zurich have similar area, they have different system for solid waste management. It was noted positively that the two municipalities have selective collection and send their waste to final destination properly, but the quality of processes in Sao Leopoldo is lower than Zurich, resulting in a smaller volume of material re-inserted in the chain of production and increasing the volume of waste sent to landfill. In other way, the management model of Zurich is more expensive, especially about incineration, but the billing system and energy trading involves the people and pay the operations. The research showed some points that can be improved in the two cities, which can be on future a basis for other municipalities. It also supported the understanding that each step has its management peculiarity, that must be planned and controlled, because the final quality of management is attained by all operations together.
36

Estudo comparativo de processos de gaseificação de resíduos sólidos urbanos no Brasil. / Sem título em inglês.

Araújo, Ramires Menezes da Silva 21 June 2016 (has links)
Os resíduos sólidos urbanos (RSU) no Brasil são na grande maioria direcionados para aterros e lixões a céu aberto, onde ocupam grandes áreas, geram transtornos relacionados ao trafego aéreo, emitem gases responsáveis pelo efeito estufa sem o devido reaproveitamento energético. Como alternativa para a minimização do passivo ambiental causado pelos RSUs e potencial reaproveitamento energético propõe-se um estudo comparativo de processos de gaseificação desses resíduos em diferentes meios gaseificantes. A modelagem e simulação dos processos foram feitas aplicando-se o método de minimização da energia livre de Gibbs não estequiométrica. Considerou-se a quantidade de resíduo sólido urbano destinado da sub-região de Campo Limpo - São Paulo - e a sua composição representativa expressa pelo método ultimate-analysis. O processo de gaseificação foi implementado em simulador de processo e o estudo se concentrou nas etapas do processo de gaseificação, investigando-se a ação dos seguintes meios gaseificantes: ar, vapor e mistura ar e vapor. Os principais resultados analisados foram a composição do produto da gaseificação e o potencial energético do produto. / The major destiny of Municipal Solid Waste (MSW) in Brazil is landfill. These sites occupy large areas; most of them are open, being simply disposal areas. This situation causes several problems ranging from greenhouse gases to air traffic jeopardizing. The use of MSW in energy generation addresses these problems, once it is one of most promising solutions to MSW treatment. This work is the study of gasification from the energy potential. It was carried out through minimization of Gibbs energy in a process simulator. The MSW considered was the one from area of Campo Limpo in São Paulo city. Its composition was expressed by ultimate analysis. The use of different gasification agents included air, steam and their mixtures was analyzed. The results were HHV and composition of generated gases.
37

Municipal solid waste disposal in developing countries : a case study of Wa Municipality, Ghana

Bowan, Patrick A. January 2018 (has links)
Municipal solid waste management (MSWM) is a global challenge and the situation is worse in urban areas of developing countries due to ineffective disposal systems. In many industrialised countries, waste minimisation and recycling/reuse policies have been introduced to reduce the amount of waste generated, and increasingly, alternative waste management practices to waste disposal on land have been implemented to reduce the environmental impacts of MSWM. Nevertheless, research and MSWM in most developing countries have largely concentrated on waste collection. This doctoral study investigates how planning and decision-making for MSW disposal in developing countries with similar circumstances and MSW problems to Ghana can be improved, using the Wa Municipality as a case study. It established the baseline scenario of MSW disposal and examined MSW disposal management and operational performances. The methodology and research design for the study was a descriptive and interpretive case study that was analysed through both qualitative and quantitative research methods. The key research findings indicate that the current state of MSW disposal management performance in Ghana does not present an enabling environment for effective MSW disposal. Also, the present MSW disposal practices in the case study area and Ghana in general consist of some waste collection, transportation and open dumping, where the entire amount of waste is open dumped without pre-treatment. Evaluation of MSW disposal operational performance through modelling and scenario analysis showed that open dumping/landfilling of waste creates copious health effects (0.0001519 lbs/year on average), whereas, MSW disposal in an integrated solid waste management (ISWM) system optimises the minimisation of health effects (-0.0005812 lbs/year on average). The study developed and validated a framework for the improvement of planning and decision-making for MSW disposal, which can easily be applied in the context of developing countries. Also, the developed framework provides a theoretical standpoint for the concept of MSW disposal in ISWM. Appropriate MSW disposal treatment technologies based on the developed framework could be applied to ameliorate the impacts of MSW disposal in Ghana and other developing countries.
38

Exploratory Study of Waste Generation and Waste Minimization in Sweden

Kuslyaykina, Dina January 2013 (has links)
The current thesis presents an exploratory study on municipal solid waste generation and minimization in Sweden, with a focus on their connection to basic socio-economic parameters. The fundamental goal of the study is to investigate into correlations and interdependencies between waste generation, waste minimization and basic socio-economic characteristics on municipal level, and to search for models for explanation of waste management parameters through socio-economic factors. Theoretical background involves reasoning on the role of municipal waste management in sustainable development, and extensive analysis of framework, legislation and organization of municipal solid waste management in Sweden. Practical part presents correlation analysis of data, which proved that socio-economic parameters do not explain differences in waste management performance of Swedish municipalities; however they are closely connected to differences between municipalities in aspect of presence of waste-related data.
39

Substantive and procedural equity in environmental planning: A case example of planning thermal treatment facilities for municipal solid waste in the Province of Ontario, Canada

Antadze, Nino 03 July 2013 (has links)
Over the last few decades, thermal treatment of municipal solid waste (MSW) has been strongly opposed in North America. The reasons for public opposition are complex and could vary from community to community. Typically, public antagonism towards thermal treatment option is clearly revealed during the planning process of energy-from-waste facilities. Concepts such as NIMBY (Not In My Back Yard) have become synonymous with the siting of MSW thermal treatment facilities. Given the highly controversial nature of such projects, effective organization and conduct of the municipal planning process is of high importance. The literature suggests that public opposition can be fuelled by the perception of unfair outcome and unfair planning process. Therefore, the equity dimension of the planning process has gained importance. This research explores the planning processes surrounding the development of thermal treatment plants for MSW in the province of Ontario, Canada by focusing on the equity dimension. The research aims to reveal the role and the nature of substantive equity, procedural equity, and cost and time efficiency, as well as the role of contextual elements in planning processes. Additionally, the research intends to provide recommendations on the effective incorporation of the equity dimension into the waste management planning processes. Through a review of the literature on planning controversial facilities with a focus on waste disposal plants, it was revealed that the clear delineation of substantive and procedural equity as well as the identification of the main elements that fall under these notions are absent. Different studies present various elements of substantive and procedural equity, but they fall short in consolidation and analysis of linkages among the elements. In addition, it was revealed that the study of the contextual elements in relation to substantive and procedural equity has been quite limited. Three research questions were identified that were informed by two assumptions derived from the consulted literature. To answer the research questions, three cases of planning thermal treatment plants in Ontario were investigated using qualitative research methods. The first case studied the Halton region thermal treatment project that was initiated in 2006 but was soon dropped without reaching the stage of full environmental assessment. The second case study focused on the Niagara-Hamilton thermal treatment project that was a joint effort between the city of Hamilton and the regional municipality of Niagara to find a local solution to the waste problem. An environmental assessment was conducted; however, before its completion the parties decided to stop the project and concentrate on other waste management alternatives. Finally, the third case studied the Durham-York thermal treatment project that underwent a full environmental assessment process and is currently close to completion. This research contributes towards expanding the conceptual discourse about the role of equity in planning waste disposal facilities with a particular emphasis on thermal treatment plants. More specifically, the thesis contributes towards delineating the notions of substantive and procedural equity and distinguishing their elements. It introduces the notion of context and explores those contextual elements that influence substantive and procedural equity during planning processes for thermal treatment facilities. As a result, the thesis develops a comprehensive analytical framework that consolidates the major elements that fall under the domains of substantive equity, procedural equity, and context that have previously been dispersed in the literature. In addition, the research establishes linkages among the elements within each domain and across domains. Based on the findings of the case studies, the notion of distributional equity is reconsidered. Whereas the distributional aspect of the equity dimension is undoubtedly important, the thesis concludes that the substantive equity should go beyond the locational aspect of planning. The existence of cross-domain linkages and their importance and diversity confirms that the notion of equity should be studied and discussed in broader terms which acknowledge not only procedural or distributional issues, but also contextual elements and efficiency questions. The existing scholarship places particular emphasis on locational considerations (siting) and procedural issues; however, it fails to present a comprehensive and multidimensional view of equity and explain how this is embedded within the broader context. This research is an attempt to present equity with all its diversity and complexity and build a foundation upon which further work in this direction can be conducted. More broadly, this research contributes to the better understanding of the perceptions and motivations behind public opposition towards infrastructure projects, and particularly waste management facilities. Given the complex nature of public opposition phenomenon, the research addresses the need to build an in-depth understanding of public motivations and perceptions that shape attitudes towards proposed projects.
40

Sustainability of Municipal Solid Waste Management in Nigeria : A Case Study of Lagos

Agbesola, Yetunde January 2013 (has links)
Waste generation is an unavoidable product of man’s activities, however, sustainable management of such waste is a challenge faced in many countries today. Nigeria, a developing country in Africa, has been in a quandary of how to efficiently manage the municipal solid waste its population generates. Many states in the country lack adequate plans and infrastructure required for efficient and sustainable management of municipal solid waste. For Lagos, the most populous and popular state in Nigeria, the problem is further compounded by its rather large and still increasing population. In this research, Lagos is taken as a case study; the extant trend for solid waste handling in households, trends in the formal and informal sector as regards solid waste management from household collection to final disposal are focused upon. Many countries, particularly the developed ones, have employed options in the waste management hierarchy for sustainable management of their municipal solid waste and the blend of options employed is usually highly dependent on local factors. Following the waste management hierarchy, possible options for sustainable municipal solid waste management in Lagos are discussed. It is concluded that waste reduction, reuse, recycling and composting are potential management options for the state. Landfilling will remain an important option for final disposal but reliance on this method could be significantly reduced if management options are exploited to the maximum in a sustainable solid waste management structure.

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