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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.
21

The Role of Local Knowledge in planning and managing urban solid waste: the tale of two (2) West African Cities, Accra and Kumasi, Ghana

Demanya, Benoit Klenam 28 January 2007 (has links)
Ongoing and potential developments with regards to solid waste management have raised concerns about well being in African cities. There is also growing concern among environmental managers, scientists, and the public that the pace and scale of human activities may lead to adverse environmental and health impacts. These concerns have been worsened by two factors: (1.) That all attempts so far made at dealing with the present situation of solid waste handling in African cities have either failed or only met with moderate success; and, (2.) There is significant economic, spiritual and cultural value placed on the city's development in Africa, therefore, a deterioration in its environment spells further difficulties for improving conditions of development. To date however, very little research has been conducted on the role local knowledge has to play in managing urban solid waste in the context of African cities. This study is a contribution on this topic, using case study cities of Accra and Kumasi in Ghana, West Africa where it was found that local knowledge plays a role not only in the day-to-day decision making of the actors involved, but also in the management of solid waste activities through, the employment of appropriate technology, the creation of awareness around local waste practices, education, adherence to norms and beliefs, and also in stopping littering and encouraging proper waste practices.
22

Municipal Solid Waste Management in an urban area of China: Case studies of Shanghai, China and Linköping, Sweden.

Yang, Cha January 2011 (has links)
With the rapid and large increase of waste quantities, China, surpassed the USA as the world’s largest municipal solid waste (MSW) generator since 2004. The phenomena and critical issues of MSWM in China inspired this paper to investigate and analyse the MSWM in an urban area of China. Comparing with the increasing rates of MSW generation, little has been done concerning the municipal solid waste management (MSWM). Not only the local government and authorities are responsible for the MSWM, but also the individuals are playing a significant role in MSWM. An integrated waste management system should be built in order to improve the holistic MSW system and reduce the waste production. The aim of the study is to investigate and analyse the current status and problems of MSWM in an urban area of China and to analyse to what extent a viable reduction of the MSW can be implemented and management systems to be improved in the near future. In this study, two case studies of Shanghai and Linköping are employed and compared to explore the challenges and potentials for improving the MSWM system in China. The result indicated that inadequate facilities and infrastructure, less advanced technology, insufficient public participation, low awareness of environmental protection, problems in policy and laws are the major barriers for the improvement of MSWM. Involving international environmental cooperation activities, planning a sustainable and comprehensive policy and framework for MSWM, introducing economic incentive approaches, promoting the capacities of waste management technologies, raising public environmental awareness are believed to be viable solutions to improve the MSWM system in China.
23

Examining solid waste management issues in the City of Bryan

Arekere, Dhananjaya Marigowda 12 April 2006 (has links)
Economic aspects of household recycling behavior and attitudes in City of Bryan are examined to improve solid waste management policies in the city. Using survey data collected by mail and personal interviews, residents’ attitudes towards solid waste management are analyzed, in general, and specifically, the factors influencing recycling behavior examined using logistic regression. In addition, three alternative policies are presented to respondents. First, support for an additional drop-off recycling center (Policy I) is examined. Second, WTP for two different recycling programs, curbside recycling service (Policy II), and curbside recycling with a drop-off recycling center (Policy III), as a function of socio-economic factors thought to influence WTP are computed using contingent valuation method, an indirect valuation tool. Finally, preference for a particular policy among the three alternatives presented to the residents of Bryan is explored. Because of the different data collection modes and assumptions on the bid prices two logit models are estimated to examine recycling behavior, and Policy I and two multinomial logit models for the most preferred policy, whereas four logit models are estimated for Policy II and III. The estimated models are similar both within the Policies and between the Policies in terms of the affects of variables, significance of coefficients, and consistency with previous studies indicating a potential set of factors that can be used to explain WTP for recycling services. Bryan residents that are female, white, employed, have higher incomes, have children, own a house, and are self-perceived environmentalists tend to recycle more. Similarly, males, nonwhites, older respondents, students, non-environmentalists and non-recyclers are more likely to support an additional drop-off center. WTP for Policy II is positively influenced by males, whites, respondents who are employed, low-income respondents, environmentalists, non-recyclers, and those who support Policy I. In comparison, WTP for Policy III is positively influenced by females, whites, respondents who are employed, younger respondents, environmentalists, non-recyclers, and those who support Policy I. In the case of both Policies I and II, the bid price negatively influences WTP as expected. While the WTP for Policy II is slightly higher than the estimated cost of a curbside recycling service ($2.50), the WTP for Policy III is lower than the estimated cost. No consistent pattern emerges across most of the coefficients and the four possible alternatives, three proposed policies and the current situation. However, probabilities computed using the multinomial logit results is the highest for Policy II, followed by either Policy III or no change to the existing solid waste management policy.
24

Sustainable municipal solid waste management: A qualitative study on possibilities and solutions in Mutomo, Kenya

Selin, Emma January 2013 (has links)
This report investigates the possibilities and solutions for a sustainable municipal solid waste management in the community of Mutomo, situated in Kitui County, Kenya. The aim was to formulate an action plan to start reaching for a sustainable development in the waste sector, with citizen participation. Specific research questions were to find requests and ideas from the community members. Also, how the Swedish solid waste management system is built up in order to find potential good examples. Qualitative methods for data collection were used both in-depth interviews and focus group discussions conducted. Data collection was done with the help of an interpreter; interviewing guides and a recording device were used. The data was transcribed and thematic analysis done using NVivo. The interviews and discussions resulted in many requests and ideas regarding solid waste management. In brief; a legal dumping site, health education of the advantages of managing waste and the disadvantages if not, increase of public dustbins, increase of people employed for waste collection, an organized system for trade of waste and improved future planning of the town by the local authorities. To conclude, if a sustainable development within the waste sector is to be initiated, the local authorities have to take action and shoulder their responsibility. Improved collaboration between them and the public health office, community members and private stakeholders is essential. The proposed action plan is a good tool to use when initiating this work and would be created through co-operation with residents in Mutomo.
25

A systems approach to community engaged integrated solid waste management in Todos Santos Cuchumatan, Guatemala

Marshall, Rachael 11 January 2013 (has links)
Solid waste management (SWM) is a growing problem in developing countries around the world. In Guatemala, indigenous communities, which are predominantly rural and remote, are particularly hard hit by a lack of basic SWM services. Todos Santos, situated in the Cuchumatanes mountain range of northwestern Guatemala, is one such community. As projects developed, planned, and implemented from 'the top down' continue to be ineffective, the literature provides little insight about remote communities' perspectives on exactly what issues SWM creates, influences, and exacerbates, and how they might respond to these concerns themselves. Using a participatory systems approach, this study investigated the systemic structures and behaviours that maintain and exacerbate SWM challenges in Todos Santos, and where key places (leverage points) to intervene in the system may exist. The study presents a wide selection of locally appropriate SWM solutions to target these leverage points in the form of four future scenarios These scenarios act as a step-wise implementation plan for gradual implementation in the community, each building upon the previous, ultimately reaching a community-defined vision for SWM.
26

Análise do gerenciamento dos resíduos sólidos domiciliares do município de Ilha Solteira - SP /

Pereira, Gracely Ortega Tavares. January 2011 (has links)
Orientador: Luzenira Alves Brasileiro / Banca: Dib Gebara / Banca: Leonardo de Barros Pinto / Resumo: A eficiência da gestão dos resíduos sólidos domiciliares gera impactos diretamente no bem- estar de toda a população do município, mas em especial nas pessoas que trabalham com a coleta, separação e comercialização dos materiais recicláveis. O objetivo desta dissertação é analisar as partes integrantes do sistema de gerenciamento de resíduos sólidos domiciliares do município de Ilha Solteira - SP, desde a geração dos resíduos sólidos nas residências até a sua destinação final em aterros e/ou separação e comercialização pela cooperativa de materiais recicláveis do município. A pesquisa foi dividida em três etapas. A primeira etapa consistiu em realizar um levantamento de dados sobre a destinação dos resíduos sólidos domiciliares no município de Ilha Solteira - SP. A segunda etapa consistiu em entrevistar os munícipes com o objetivo de levantar qual é o tamanho da parcela da população que realiza a separação dos materiais recicláveis, como estes são acondicionados e quais os materiais que são separados. E a terceira etapa foi a caracterização gravimétrica dos resíduos sólidos domiciliares destinados ao aterro sanitário, segundo o método de quarteamento. A pesquisa forneceu resultados sobre a redução da vida útil do aterro sanitário, a quantidade de materiais com valor econômico que está sendo desperdiçado no aterro e a renda que deixa de ser gerada para as pessoas diretamente envolvidas com a comercialização dos materiais recicláveis. Com os resultados obtidos nesta pesquisa, a municipalidade que opera e gerencia os resíduos sólidos terá informações que poderão subsidiar o planejamento e as ações de curto, médio e longo prazo; no sentido de melhorar a eficiência e as condições econômica, ambiental e social do sistema de gestão dos resíduos sólidos domiciliares de Ilha Solteira - SP / Abstract: The efficient management of solid waste directly impacts the welfare of the entire population of the city, but especially those working with the collection, separation, and marketing of recyclable materials. The objective of this dissertation is to study the integral parts of the management system of solid waste in the city of Ilha Solteira-SP, from the generation of solid waste in the home until its final destination in landfills and/or separation and the cooperative for marketing recyclable materials of the city. The research will be divided into three phases. The first step will be to conduct a survey of preliminary data on the allocation of household solid waste in the city of Ilha Solteira-SP. The second stage is to interview the townspeople in order to discover what portion of the population carries out the separation of recyclable materials, wich of these are wrapped and which materials are separated. The third step performed is gravimetric characterization of household solid waste destined for the landfill, using methods of quartering. From the results obtained in this research, the municipality that operates and manages the solid waste will have information that could support the planning and the actions in short, medium and long term, to improve the efficiency and effectiveness of economic, environmental, and social management system for solid waste Ilha Solteira - SP. It will be known: the amount of materials with economic value that are being wasted in the landfill, as well as an estimate of the remaining service life of the landfill, and the income that is not generated for the people directly involved with the marketing of recyclable materials / Mestre
27

Estudo da separação e aproveitamento da parte metálica e de óxidos presentes no resíduo gerado no corte de rochas ornamentais. / Study of separation and reuse of metallic part and present oxides in residue generated in ornamental rocks cutting.

Eduardo Junca 30 November 2009 (has links)
Este trabalho tem como objetivo o estudo do reaproveitamento da parte metálica e a caracterização dos óxidos presente no resíduo de granito gerado na etapa de desdobramento. Inicialmente, foi feita a caracterização química e física do resíduo através de análise química, difração de raios-X, microscopia eletrônica de varredura e análise granulométrica. Após a caracterização do resíduo, foi dado inicio aos processos para a recuperação do Fe metálico que envolveram: separação magnética, mesa concentradora e ciclonagem. A separação magnética foi realizada em três etapas: a primeira onde se utilizou um separador magnético a úmido de alta intensidade, onde foi utilizado apenas o campo magnético remanescente do equipamento. Na segunda etapa, onde o material magnético obtido na primeira etapa foi submetido a uma nova separação magnética manual utilizando um imã de terras raras. Na terceira etapa, o material magnético obtido com o imã de terras raras foi submetido a uma separação magnética manual com um imã ferrítico. Nos ensaios de mesa concentradora, foram realizadas variações na inclinação da mesa, freqüência de oscilação e vazão de água de lavagem. Já nos ensaios de ciclone, o parâmetro variado foi à pressão de alimentação. Foram realizadas variações nos parâmetros dos equipamentos com o intuito de se aperfeiçoar e definir os melhores parâmetros para a recuperação do Fe metálico. Após cada ensaio, foi realizada a análise química volumétrica para a determinação do teor de Fe metálico obtido em cada produto. Pelos resultados obtidos, o método de separação magnética foi a que apresentou os melhores resultados, sendo possível a obtenção de um concentrado ferroso com 93% de Fe metálico e um concentrado granítico com 0,6% de Fe metálico. Já nos ensaios de mesa concentradora, o melhor resultado obtido foi um concentrado ferroso com apenas 13,7% de Fe metálico, e nos ensaios de ciclone foi possível à obtenção de um produto com apenas 7,2% de Fe metálico. A partir do concentrado ferroso e granítico obtido na separação magnética foi realizada a caracterização através de microscopia eletrônica de varredura, difração de raios-X e análise granulométrica. A partir do concentrado ferroso obtido, foram produzidos briquetes com uso de 2% de cal hidratada como aglomerante. Foram realizados testes de resistência mecânica a verde e a seco nos briquetes produzidos. Foi obtido uma resistência mecânica a verde de no máximo 1,02 kN e a seco de no máximo 3,59 kN. / The aim of this work is to study the reuse of the metallic part and the characterization of oxides present in the waste from granite sawing. First, the chemical and physical characteristics of the waste were analyzed by chemical analysis, X-ray diffraction, scanning electron microscopy and size analysis. Procedures for the metallic iron recovery (magnetic separation, concentrator table, and cyclonic separation) were performed after the waste characterization. Magnetic separation was performed in three phases. First, using a high intensity wet magnetic separator, which only the remaining magnetic field of equipment was utilized. In the second phase, the magnetic material obtained in first phase was subjected to a new manual magnetic separation using rare earth magnets. In a third phase, magnetic material obtained with rare earth magnets was subjected to manual magnetic separation using ferrite magnets. In the experiments of concentrator table, were carried out changes in table inclination, oscillation frequency and wash water flow. For cyclone tests, the varied parameter was the water supply pressure. Variations in equipment parameters were performed in order to improve and decide the best parameters for recovery of metallic iron. After each experiment, volumetric chemical analysis was performed to determine the metallic iron content of each product. The results show that the magnetic separation method had the best results since it is possible to obtain a ferrous concentrated with 93.0 wt. % metallic iron and granite concentrated with 0.6 wt. % metallic iron. While for concentrator table tests, the best result presented a ferrous concentrated with only 13.6 wt. % metallic iron; and for cyclone tests, a product with only 7.2 wt. % of metallic iron was obtained. Ferrous and granite concentrated from magnetic separation were characterized by scanning electron microscopy, X-ray diffraction and size analysis. Using the obtained ferrous concentrated, briquettes were produced with 2 wt. % hydrated lime as binder. Produced briquettes were tested using dry and wet mechanical strength test. Wet mechanical strengths of up to 1.02kN were obtained, and a maximum of 3.59kN was registered to dry mechanical strength.
28

NON-INVASIVE CHARACTERIZATION OF UNSATURATED ZONE TRANSPORT IN DRY COAL ASH DUMPS: A CASE STUDY OF TUTUKA, SOUTH AFRICA

Muchingami, Innocent I. January 2013 (has links)
Doctor Scientiae / The management of the large volumes of solid wastes produced as coal combustion residue is of particular concern due to the presence of leachable metals and salts which may constitute a long term environmental risk and potential contamination of both surface and groundwater systems of the surrounding environment. In order to implement an efficient monitoring scheme and to assess the impact of the ash dump on the hydrologic system, a thorough knowledge on the migration of solutes fluxes in dry ash dumps as well as the controls on the transport of these solutes to the underlying groundwater system is required. The conventional methods which have been widely used for such applications are centred on extracting and analysing several samples from observation wells are drilled on the dump. This has however created a potentially hazardous situation as the installation of monitoring wells may result in the creation of new fluid pathways and results in further migration of leachates. Nevertheless, non–invasive characterization has often been useful in the determination of subsurface hydraulic properties and is a key step towards the solution of real-life problems in hydrology, hydrogeology and soil science. In contaminant transport non-invasive methods have often proved to be an efficient tool as compared to traditional drilling and sampling techniques which in most cases results in the creation of preferential flow paths and do not allow for the space and time resolution needed for the monitoring of hydrological and environmental processes. In this context, this study seeks to develop a generic conceptual model for the ash dump through the use of non-invasive geophysical techniques and numerical modelling techniques at the Tutuka Ash dump, Mpumalanga South Africa. Changes in electrical resistivity were used correlate changes in moisture contents during moisture and salt leachate ingression in ash dumps with a sufficient accuracy. A determination of the suitability of Archie‘s law to describe the relationship between electrical resistivity and solute transport ash medium was achieved through empirical laboratory experiments. Electrical resistivity tomography was then used as an appropriate tool for the elucidation of potential flow paths and brine dispersion in the ash dump. The flow rates through the ash dump were estimated by considering the rate of brine injection and the distance travelled by the brine plume over the time spanned in time lapse infiltration experiments. Additional geophysical profiles managed to show the lithostratigraphy of underlying hydro-geology, thereby ensuring that the knowledge of the geology can be established without the application of any intrusive methods. To ensure that development of the conceptual model of the unsaturated zone transport of the ash dump was developed with sufficient accuracy, numerical models were also used to describe solute transport in the vadose zone. The HYDRUS2D numerical package was used simulate the flux dynamics within the unsaturated zone of the coal ash medium, so as to develop a conceptual understanding of water flow and salt transport through the unsaturated zone of the coal ash medium. The results from the study suggested a conceptual solute transport model that consists of a two layers. The upper layer represented the unsaturated zone of the ash dump which was the source of any potential contaminant transport that could be of concern. The lower layer describe the underlying the subsurface environment to the ash dump which include the soil zone, the shallow aquifer and the deep fractured rock aquifer. To enable this conceptualisation, results from the numerical simulations and geophysical interpretations of the electrical resistivity profiles were the critical components for optimising the site-specific subsurface water flow and solute transport processes, as well as producing the most acceptable conceptualisation of the ash dump system that could be used in hazard assessment and mitigation against potential groundwater pollution. The conceptual models developed in this study proposed an explanation on impact of the ash dump to the hydro-geologic and the eco-hydrologic environment by proposing a scenario of contamination of the underling ash dump and the existing. In this regard, the study managed to provide important scenarios that may be necessary during mitigation procedures for both the ash dump and the wetland. Key words: non-invasive, coal ash, time lapse, electrical resistivity tomography, numerical models, HYDRUS2D, conceptual model.
29

CRITICAL EVALUATION OF LEACHATE CLOGGING POTENTIAL IN GRAVITY COLLECTION SYSTEMS AND MANAGEMENT SOLUTIONS

Unknown Date (has links)
Leachate clogging in the Leachate Collection System (LCS) due to chemical precipitations and biofilms produced by microbial activities is a common phenomenon in any Municipal Solid Waste (MSW) landfill. This study focuses on quantifying the factors that impact the micro-environment of leachate; and microbial activities that help the precipitates to form and attach to the LCS. It also evaluates the performance of operational changes that have been implemented or the potential alternatives and recommends the possible measures to reduce the severity of clogging. A field scale side-by-side pipe network, and several laboratory setups were used in this study. Calcite is identified to be the predominant phase present in the precipitates using XRD/XRF analysis which, concur with the previous studies. Microbial growth and activities enhance the precipitation of CaCO3 in LCS. Clogging in LCS pipes can be controlled if not eliminated by continuous monitoring along with frequent cleaning with physiochemical processes. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
30

Integrated solid waste management model: the case of Central Ohio district

Prawiradinata, Rudy Soeprihadi 18 June 2004 (has links)
No description available.

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