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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.
11

Prefeasibility Study for a Waste-to-EnergyApplication in Gauteng Province, South Africa

Subasinghe, Gayan January 2013 (has links)
Waste-to-Energy concept becomes increasingly popular from the perspectives of the waste management and alternative energy. South Africa, which is a country heavily dependent on the fossil fuel, can explore the opportunities of Waste-to-Energy in order to deal with increasing amount of waste generated while reducing what is deposited at non-engineered landfills, thereby increase the renewable energy share. This prefeasibility study attempts to identify Waste-to-Energy potentials in Gauteng provinceso as to develop a Waste-to-Energy facility under the new renewable Independent Power Producer procurement programme of South Africa. The analysis identifies abundant Wasteto-Energy incineration and landfill gas opportunities linked with municipal solid waste in twomunicipalities. The prefeasibility study further evaluates environmental, socio-economic aspects of Waste-to-Energy initiative. The financial viability of a Waste-to-Energy incineration facility with the Feed-in-Tariff proposed by the government of South Africa isalso detailed analysed.
12

Actions and improvements in waste management : A comparison between Halmstad University, Sweden and UNIVATES, Brazil

Holmberg, Hanna, Järnstedt, Nina-Maria January 2014 (has links)
No description available.
13

A comparison of uncertainty analysis methods for the modeling of land disposal of petroleum exploration and production waste /

Choong, Peng Kee, January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 79-80). Also available via the Internet.
14

Inhibition of methane production by ammonia nitrogen in the anaerobic digestion of poultry manure

Mohr, Nancy Ann. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 76-77).
15

E-waste management policies and consumers disposal : A comparative case-study between Milan and Paris / Politiques de gestion des DEEE et comportement de recyclage des citoyens-consommateurs : une étude de cas comparative entre Milan et Paris

Capurso, Isabella 01 December 2014 (has links)
L'objectif général de cette thèse est de tirer des enseignements sur les facteurs qui impactent l'acte de tri des DEEE des consommateurs à l'échelle urbaine. Enquêter sur le geste de tri à l'échelle urbaine signifie contribuer au débat scientifique concernant la gouvernance de déchets en ville, qui est un thème très important du fait du rôle que les espaces urbains jouent aujourd'hui en tant qu'acteurs clés de la transition vers un développement durable. En particulier, en adoptant une approche multi-échelle et transdisciplinaire, la thèse est construite comme une étude de cas comparative entre Milan et Paris, où la mise en oeuvre de la filière des DEEE est analysée et les comportements de tri des consommateurs sont interprétés. L'objectif global de l'étude n'est pas seulement de mettre l'accent sur les liens entre la dimension macro des politiques de gestion et celle des comportements individuels et sociaux, mais aussi de comprendre quelle est la configuration prise par les différents acteurs impliqués dans la gestion des DEEE et quelles sont les points faibles et forts de la chaîne. Cette réflexion devait fournir des clés de lecture utiles pour nous permettre de suggérer des méthodes alternatives de gestion des DEEE en ville ainsi que des pistes de réflexion pour encourager le bon tri des DEEE par les citoyens-consommateurs. / The overall objective of this thesis is to draw insights about the factors that impacts the act of WEEE disposal by consumers at urban scale. Investigate such issue at the urban scale means contributing to the scientific debate concerning the governance of waste in the cities, which is a very important topic because of the role that urban areas now play as key actors in the transition to sustainable development goals. In particular, by adopting a multi-scalar and cross-disciplinary approach, the analyzed and the related consumer disposal behaviour is interpreted. The overall objective of the study is not to focus on the links between the macro dimension of management policies and those of individual and social behaviours, but alsi to understand what is the configuration taken by the different actors involved in the management of WEEE and what are the strengths and weaknesses of the chain. The discussion should provide useful key-readings to frame alternative methods of management of WEEE on urban scale as well as useful insights to foster citizens consumers' proper disposal.
16

Chemical Recycling of Poly(ethylene terephthalate): Effects of Mechanical Stress and Radiation Damage on Hydrolysis

Zhang, Tongjie 10 May 2020 (has links)
Finding an effective recycling process for oceanic plastic waste is increasingly important to address environmental pollution. Plastic waste is a bountiful and sustainable resource for energy production and chemical recycling. Polyethylene terephthalate (PET), one of the most common commercialized polymers, is promising to be recycled by hydrolysis. The objective of this work was to study the effects of mechanical stress and radiation damage on PET structure and hydrolysis reactivity. Ball-milling and photo-damaging pretreatments were carried out to imitate the environmental degradation in the ocean environment. An evident decrease in crystallinity with increasing ball-milling time was observed. This decrease in crystallinity caused by fractures of chemical bonds induced by photoaging and ball-milling treatments were investigated. PET was hydrolyzed into ethylene glycol (EG) and terephthalic acid (TPA) at 200°C in tube hydrolysis reactors without catalysts. EG and TPA were recovered after PET depolymerization. Thermogravimetric analysis and Fourier-transform infrared spectroscopy indicated that the recovered TPA was purified. Qualitative and quantitative analysis of TPA and EG were performed by using UV-Visible spectrophotometer and High-Performance Liquid Chromatograph (HPLC) separately. At 200 ℃, the conversion rate of fresh and ball-milled PET samples was improved from 16-18% with a one-hour reaction time compared to 87-91% with a two-hour reaction time. This depolymerization behavior supported that the conversion rate of PET was increased with increasing reaction time at the same temperature. The experiment results, however, showed PET conversion, TPA yield, and EG yield did not improve after ball-milling and photo-damaging treatment. After retention time of 1 hour, PET conversions, yields of TPA, yields of EG of various PET samples were 16.5±1.5%, 11.5±1.5% and 0.70 ± 0.20%, respectively. Mechanical treatment and radiation damage did not affect PET reactivity significantly in this experiment. Two main reasons were discussed to explain this result. The effect of radiation damage and mechanical stress was obscured by the more dominant reaction condition, temperature. The pretreatments in this experiment were not strong enough to affect PET reactivity. Based on the current results, recommendations for the hydrolysis temperature, potential catalysts, and more robust pretreatment methods were provided for further outlook of studying environmental effects on PET hydrolysis.
17

The theory of wasting assets with reference to the regulation and pricing of gold in the South African gold mining industry

Boyle, Georgina Ann 29 September 2023 (has links) (PDF)
The main aim of this thesis is to present and critically analyse the theory of wasting assets with regard to extractive mineral industries in general and to the pricing and regulation of gold . ii'" particular. Furthermore, to consider the contention that the. price of minerals {such as gold) has been "too low11 in the current generation and that market forces have· led to a 11 too rapid11 depletion of these · resources. The argument that H is the government's duty to intervene and extend the lives of the mines is· also queried •. A detailed examination of the South African· gold mining taxation formula attempts to show how this type of· government intervention (in the for in of .a sliding scale taxation formula) results in uneconomic act ions by mine owners and non-optimal extraction patterns of the resource The contention is put forward that, given certain considerations, market ibrces should lead to the most optimal use of an exhaustible resource where property rights exist and are def inable0 Unlike common property resources, such as the fisheries, where market .forces fail to make the most optimal use of the resource, government intervention is unjustified The scope of the paper is intended to cover both the underlying theory of wasting assets and to relate this theory to gold in part icu1 ar., The determinants of the gold price will be considered as well as the effects of government intervention via· the gold mining taxation formula on the South· African gold mining industry. Hence, the thesis is divided into two sections: "Theoretical 11 and "Gold and Gold Mining". With regard to the method of paper - Literature. from as far back ,· as 1931 regarding .the theory of wasting assets, was collected and .analysed. The information for the section on 11 Gold and Gold Mining" was collected from the various organisations involved in the industry, notably the Chamber of Mines _and the Mineral Engineering Department . . 9f the University of the Witwatersrand. Information regarding the Gold Mining Taxation and Lease Formulae was obtained from the various Government Reports that have been printed since the introduction of the Mining Taxation. Act No. 6 in 1910
18

Bridging science and society in the debate over high temperature incineration of PCBs

MacGuire, Frances January 1995 (has links)
No description available.
19

Informing Municipal Planning: Lessons Learned from the Development of a By-Product Waste Exchange in Toronto, Ontario.

Wilson, Tessa January 2013 (has links)
Municipal Solid Waste Management (MSWM) is becoming an increasing challenge for municipal authorities due to global increases in waste quantities. Other challenges include; changes in waste composition and increasing concern for the environment. As cities continue to grow, so too will the waste. The management of waste therefore becomes critical to municipal planning. Health and sanitation, aesthetics, minimization of pollution and the monitoring of critical resources are just some of the reasons municipalities must manage and control solid waste. Using the Toronto Pearson Eco Business Zone as a case study, this thesis explores how waste (by-product) exchanges might inform municipal planning and how waste exchanges could advise planners and academics in managing growing amounts of municipal waste. The Toronto Pearson Eco Business Zone is a developing Eco Industrial Park which utilizes theories and concepts of ecology and resource recovery to reduce waste. Utilizing a qualitative research approach, data was obtained from businesses throughout the Park to develop a waste exchange database. The results of this study suggest that the application of concepts underlying Eco Industrial Parks such as a by-product exchange program can assist to drive resource recovery and sustainable waste management practices. However, users of the exchange are highly uneducated or unaware of the links between waste and resources. This was made evident by the fact that companies were more inclined to continue the practice of revenue recycling over the sustainable approach as offered by the exchange. This conclusion suggests that although a waste exchange can help to drive resource recovery, increased education and awareness through mandatory regulations could help to drive resource recovery even further. For the greater success of waste management in Canada, the Government should take action to regulate the planning and organization of waste exchanges in industrial and surrounding areas. The Pearson Eco-Business by-product exchange suggests that cities should not be planned without consideration of solid waste and resource recovery therefore suggesting that concepts related to Eco-Industrial parks should be applied to all municipal and city planning moving forward.
20

Informing Municipal Planning: Lessons Learned from the Development of a By-Product Waste Exchange in Toronto, Ontario.

Wilson, Tessa January 2013 (has links)
Municipal Solid Waste Management (MSWM) is becoming an increasing challenge for municipal authorities due to global increases in waste quantities. Other challenges include; changes in waste composition and increasing concern for the environment. As cities continue to grow, so too will the waste. The management of waste therefore becomes critical to municipal planning. Health and sanitation, aesthetics, minimization of pollution and the monitoring of critical resources are just some of the reasons municipalities must manage and control solid waste. Using the Toronto Pearson Eco Business Zone as a case study, this thesis explores how waste (by-product) exchanges might inform municipal planning and how waste exchanges could advise planners and academics in managing growing amounts of municipal waste. The Toronto Pearson Eco Business Zone is a developing Eco Industrial Park which utilizes theories and concepts of ecology and resource recovery to reduce waste. Utilizing a qualitative research approach, data was obtained from businesses throughout the Park to develop a waste exchange database. The results of this study suggest that the application of concepts underlying Eco Industrial Parks such as a by-product exchange program can assist to drive resource recovery and sustainable waste management practices. However, users of the exchange are highly uneducated or unaware of the links between waste and resources. This was made evident by the fact that companies were more inclined to continue the practice of revenue recycling over the sustainable approach as offered by the exchange. This conclusion suggests that although a waste exchange can help to drive resource recovery, increased education and awareness through mandatory regulations could help to drive resource recovery even further. For the greater success of waste management in Canada, the Government should take action to regulate the planning and organization of waste exchanges in industrial and surrounding areas. The Pearson Eco-Business by-product exchange suggests that cities should not be planned without consideration of solid waste and resource recovery therefore suggesting that concepts related to Eco-Industrial parks should be applied to all municipal and city planning moving forward.

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