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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.
391

Skarreling for Scrap: a case study of informal waste recycling at the Coastal Park landfill in Cape Town

Huegel, Christoph Peter January 2013 (has links)
Magister Artium - MA / A widespread phenomenon on dumpsites in the developing world, subsistence waste picking is also a common practice at the city-owned Coastal Park Landfill (CPL) in Muizenberg. Poor unemployed people from the townships of Capricorn, Vrygrond and Hillview, situated at the foot of the tip ―skarrel for scrap‖ every day. The word skarreling is an Afrikaans term meaning to rummage or scrabble, scuttle or scurry. Thus, if one talks of ―skarreling for scrap‖, it generally refers to poor people trying to eke out a living by looking for recyclables in the waste that can be put to personal use or turned into money. In the two decades since the transition to democracy, South Africa and the City of Cape Town (CCT) have formulated a number of framework and subordinate policies which express their commitment to sustainable development (SD). SD aims to achieve a balance between its three components, economic, environmental and social sustainability. Thus, SD is not only about increased economic efficiency and stability, while at the same time reducing pollution and handling natural resources more thoughtfully; it is also about promoting social equity by reducing poverty and empowering the poor. This study is guided by the assumption that waste pickers in developing countries play an important part in recycling efforts, and that recycling in turn is an integral component of SD, which is the guiding principle of South African policy-making. In an ideal scenario – as implicitly promised by the policies on SD – the management of solid waste should pursue the economic and environmental goals of SD by promoting recycling and should be aligned with the goal of creating sustainable livelihoods. However, the reality in the CCT is a different one. Landfill skarreling in the CCT, and particularly at CPL, is accompanied by conflict and a criminalisation of the skarrelaars. The CCT decided to phase out landfill salvaging in 2008, and subsequently has put a lot of effort into keeping skarrelaars away from its landfills. The implications of this decision – job losses for poor people and a potential increase in crime – have not been thought through. There is thus a dysfunctional triangular relationship around waste recycling in the CCT, leading to tensions between (1) the City‘s commitment to SD; (2) 5 its approach towards recycling (as part of solid waste management) in policy and practice; and (3) the livelihoods of the poor in adjacent townships. In the CCT the goals of SD are undermined by the City‘s recycling strategies, with adverse effects for the livelihoods of the people who live off skarreling. There are several causes for this disjuncture between policy and reality. The first has to do with ignorance on the side of the policymakers. They seem to be badly informed about the extent and nature of skarreling, perhaps assuming that this activity is performed only by a few people who need quick cash for drugs. The second cause can be attributed to the neoliberal macro-policies pursued in South Africa, as well as to the global competition between cities for investment. This neoliberal urbanism leads cities like Cape Town to re-imagine themselves as ―world (-class) cities‖, in which poor waste pickers are perceived as a disturbing factor. In the CCT, this goes hand in hand with an approach reminiscent of the apartheid mindset, which saw the need to control poor, black (and potentially unruly) people. The dissertation therefore focuses on the core themes of sustainable development, (urban) neoliberalism, and informality in combination with a case study of the informal waste pickers at the chosen landfill site. Writing from a political studies angle, this study is framed as a policy critique: it argues that the policies around SWM ignore South African realities, and that the SD policies and their implementation lack coherence. Moreover, the conflict between the skarrelaars and the CCT at the CPL is rooted in inadequate national and local legislation which does not acknowledge the role of informal waste pickers in SWM and aims at excluding rather than including them. If waste pickers were supported in their recycling efforts in both policy and practice, this would be a win-win situation for the state/city (economic benefits and less crime), the skarrelaars (regular employment and incomes) and the environment (less waste buried on landfills). The case study is primarily designed as a qualitative study, but also includes quantitative elements as it attempts a first quantification of the extent and nature of skarreling at the CPL site, one of only three operating dumpsites in Cape Town. The aim on the one hand is to estimate the contribution of the skarrelaars to waste reduction (and therefore to sustainability) in the City, especially since the waste they collect is not buried on the landfill, thereby prolonging the operational life span of the landfill. The other aim is to assess the role of the skarrelaars as an economic factor in the township, in particular the question of how important the incomes generated from skarreling are for their individual livelihoods and for the community as a whole.
392

Waste Management in the Mekong Delta : Characterisation and evaluation of organic waste

Andersson, Daniel January 2017 (has links)
This degree project investigated landfills that takes care of municipal solid waste in an area around the Mekong delta, namely An Giang province, Vietnam. The main objective for this study was to provide basic work in order to create a discussion with the local food markets to separate the household’s food waste from the rest. Such a discussion is possible to create through collaboration with local authorities and inform or guide stakeholders on how waste management can be improved, out of existing knowledge from Sweden. Therefore, this study aims to illuminate and give knowledge for improvements in questions regarding efficiency, organisation, participation, recycling and opportunities associated with a more efficient waste management system.Since a significant percentage of the household waste generated in Long Xuyen City, An Giang province are organic, the opportunity to convert organic waste into soil amendments was examined. Leachate from one of the landfills in the area was also analysed in order to get further understanding for its composition, focusing on organic parameters. / Det här examensarbetet undersökte deponier som tar hand om hushållsavfall i ett område runt Mekongdeltat, närmare bestämt An Giang provinsen, Vietnam. Det främsta målet för den här studien var ett ge underlag till att skapa en diskussion med lokala matmarknader för att få dem att separera hushållens matavfall från övrigt avfall. En sådan diskussion är möjlig att skapa genom samarbete mellan lokala myndigheter och att informera eller vägvisa intressenter om hur avfallshanteringen kan förbättras, ut ifrån befintlig kunskap från Sverige. Därför fokuserar den här studien på att förklara och ge kunskap för förbättringar i frågor rörande effektivitet, organisation, deltagande, återvinning och möjligheter associerade med ett mer effektivt avfallshanteringssystem. Eftersom en stor andel av hushållsavfallet som genereras i Long Xuyen, An Giang-provinsen är organiskt, undersöktes möjligheten att konvertera organiskt avfall till jordförbättringsmedel. Lakvatten analyserades från en av deponierna i området för att få en djupare förståelse för dess sammansättning, med fokus på organiska parametrar.
393

Cr (VI)-Containing electri furnace dust and filter cake: characteristics, formation, leachability and stabilisation

Ma, Guojun 18 October 2006 (has links)
In South Africa, the ferrochromium industry produces approximately 100,000 t bag house filter dust and slurry, while the stainless steel industry produces 24,000 t of dust annually [17,39]. The toxic substances in these wastes potentially pose a threat to the environment and human health, especially Cr (VI) due to its toxic, carcinogenic, highly soluble and strongly oxidizing properties. Therefore, the existence and treatment of wastes from stainless steel and ferrochrome production remain a challenge and an issue of concern. The increase of environmental legislation globally and the trend towards sustainable development are drives for alternatives to landfill. In the present thesis, the characteristics, formation mechanisms, leachability and stabilisation of the Cr (VI)-containing electric furnace dust and filter cake were investigated using various techniques such as XRD, XRF, TG/DTA, XPS, SEM-EDS, FT-IR, Raman spectrometer and UV/Vis spectrometer. The electric furnace dust and filter cake are very fine particles. Stainless steel dust forms by the entrainment of charge materials, evaporation or volatilisation of elements and ejection of slag and metal by spitting or the bursting of gas bubbles. It was found that ferrochrome dust is formed by the ejection of slag and metals droplets from the electrode hole, the entrainment of charge materials, vaporisation as well as the formation and precipitation of compounds from vaporised species in the off-gas duct. Filter cake contains crystal phases (CaF2 and CaSO4 ) and metal rich amorphous phases. It is formed due to super saturation and precipitation. Leaching experiments on the wastes showed that Cr (VI) rapidly leaches out by distilled water. Bricks were produced by mixing wastes (stainless steel plant dust, ferrochrome dust and filter cake) and clay. The optimum sinter parameter was found to be 1100oC and 5 hours for a 50wt% SPD-50wt% AS mixture in the brick. The leachability of Cr(VI) is strongly influenced by the mass%CaO/mass%SiO2 ratio and alkali metal oxides content in the wastes. The emission factors from the stabilised wastes (SPD, FCD1, FCD2 and FC) are similar to those reported for the cement industry. Semi-dynamic leaching tests indicated that the predominant leaching mechanisms of chromium species are initial surface wash-off followed by matrix diffusion. / Thesis (PhD (Metallurgical Engineering))--University of Pretoria, 2007. / Materials Science and Metallurgical Engineering / unrestricted
394

Právní nástroje odpadového hospodářství / Legal instruments of waste management

Humpálová, Šárka January 2017 (has links)
The purpose of my thesis is primarily to describe the system of the waste management instruments and their role in the environmental protection and to analyse if the system is working well and is able to reach the outlined binding goals in the future. Due to the planned legislative changes the attention is paid to the individual sources of law. Although I focused more on the national law, I did not forget to mention the international and European law either. In the partial conclusions and in the finale of the thesis itself I summarize and generalize acquired knowledge and try to indicate some of the weak spots in the waste legislation.
395

A Novel Computational Approach for the Management of Bioreactor Landfills

Abdallah, Mohamed E. S. M. January 2011 (has links)
The bioreactor landfill is an emerging concept for solid waste management that has gained significant attention in the last decade. This technology employs specific operational practices to enhance the microbial decomposition processes in landfills. However, the unsupervised management and lack of operational guidelines for the bioreactor landfill, specifically leachate manipulation and recirculation processes, usually results in less than optimal system performance. Therefore, these limitations have led to the development of SMART (Sensor-based Monitoring and Remote-control Technology), an expert control system that utilizes real-time monitoring of key system parameters in the management of bioreactor landfills. SMART replaces conventional open-loop control with a feedback control system that aids the human operator in making decisions and managing complex control issues. The target from this control system is to provide optimum conditions for the biodegradation of the refuse, and also, to enhance the performance of the bioreactor in terms of biogas generation. SMART includes multiple cascading logic controllers and mathematical calculations through which the quantity and quality of the recirculated solution are determined. The expert system computes the required quantities of leachate, buffer, supplemental water, and nutritional amendments in order to provide the bioreactor landfill microbial consortia with their optimum growth requirements. Soft computational methods, particularly fuzzy logic, were incorporated in the logic controllers of SMART so as to accommodate the uncertainty, complexity, and nonlinearity of the bioreactor landfill processes. Fuzzy logic was used to solve complex operational issues in the control program of SMART including: (1) identify the current operational phase of the bioreactor landfill based on quantifiable parameters of the leachate generated and biogas produced, (2) evaluate the toxicological status of the leachate based on certain parameters that directly contribute to or indirectly indicates bacterial inhibition, and (3) predict biogas generation rates based on the operational phase, leachate recirculation, and sludge addition. The later fuzzy logic model was upgraded to a hybrid model that employed the learning algorithm of artificial neural networks to optimize the model parameters. SMART was applied to a pilot-scale bioreactor landfill prototype that incorporated the hardware components (sensors, communication devices, and control elements) and the software components (user interface and control program) of the system. During a one-year monitoring period, the feasibility and effectiveness of the SMART system were evaluated in terms of multiple leachate, biogas, and waste parameters. In addition, leachate heating was evaluated as a potential temperature control tool in bioreactor landfills. The pilot-scale implementation of SMART demonstrated the applicability of the system. SMART led to a significant improvement in the overall performance of the BL in terms of methane production and leachate stabilization. Temperature control via recirculation of heated leachate achieved high degradation rates of organic matter and improved the methanogenic activity.
396

Obchodovatelná povolení v odpadovém hospodářství / Tradable permits in Waste Management

Mačková, Markéta January 2010 (has links)
In this diploma thesis is being explored the possibility of using tradable permits in waste management as an efficient tool for motivating and guiding market participants. Waste in the world each year is increasing and burdensome for the economy in terms of the cost of disposal or storage, and for the environment in terms of expanding the number of landfills. The European Union has set mandatory guidelines through a specific quantitative value of natural resources in the field of waste management, which Member States are obliged to respect. These include a minimum percentage return and recycling of packaging materials, or the maximum amount of biodegradable waste that can be stored in landfills. The Directive also set the exact dates of compliance with those commitments. The goal of the diploma thesis is to critically analyze existing knowledge and experience in using tools of tradable permits. On the economic analysis follows the discussion options for wider application of this instrument in the regulation of waste management.
397

Planning and Valuation of Investment Project - MSW Incinerator in Banska Bystrica / Planning and Valuation of Investment Project - MSW Incinerator in Banska Bystrica

Lúčanský, Igor January 2014 (has links)
The Master Thesis outlines planning and valuation of solid waste incinerator with energy recovery. The focus of due diligence, made before valuation, is on the assessment of the input data in regard to current and future market situation. The beginning of the thesis explains the valuation process with methods used later on. The two subsequent parts describe respectively current market situation and define data for valuation process made in Excel sheet attached. Before concluding the outcomes are compared with other possibilities with changes in financing structure.
398

Evaluation and proposed development of the municipal solid waste management system in Mexico City

Escamilla Garcia, Pablo Emilio January 2015 (has links)
The work reported involves the evaluation of technologies and management systems applied to Municipal Solid Waste (MSW). The study focuses on Mexico City, which with a population of approximately 9 million inhabitants and an estimated daily generation of 13,000 tonnes of waste, is encountering extreme waste management issues. The structures and public policies designed to provide waste management services have proved inadequate in relation to high rates of population growth and intensive business activities. The significant increase in demand has led the government of Mexico City to base public services on rudimentary techniques using obsolete equipment. The research approaches the problem through the analysis of several different aspects: (1) a comprehensive literature review of waste management including technologies and legal frameworks; (2) a general overview of the main demographic, geographic and economic aspects of Mexico City; (3) an extensive analysis of historic and future waste generation profiles and composition of waste in Mexico City; (4) an evaluation of the current status of the waste management system, including programmes, plans, facilities and infrastructure; and (5) a comparative study of the waste management system of Mexico City and the systems of selected international cities. The evaluation resulted in the identification of the following significant issues: (1) limitations in legislation related to waste management and environmental laws; (2) high population growth and increasing business activity, which contribute escalating generation of MSW; (3) ineffective public policies focused on waste management; (4) significant gaps in low levels of recycling activities; (5) obsolescence of equipment, infrastructure and facilities; (6) lack of diversification in treatment methods for MSW; and (7) failure to exploit market opportunities in the waste management sector. In addition to the evaluation of the system in Mexico City, the analysis of waste management systems in selected international cities allowed the author to identify key factors in order to develop integrated proposals. The analysis highlighted significant aspects including: legal frameworks, the participation of the private sector, waste hierarchy, and guiding principles for plans and programmes. The information enabled the design of a proposed development plan of a comprehensive waste management system in Mexico City through two main proposals. Firstly, an integrated programme for waste management in Mexico City was developed to provide feasible long-term strategies in the field of waste management. The specific objectives, goals, actions, responsibilities and time scales were defined in order to provide concrete activities under specific fields of operation. Secondly, a project to obtain funding for technology transfer structured according to technical, market and economic studies, was elaborated. The guide is aimed to exemplify an investment project through the analysis of a feasibility study related to generation of energy from biogas in a controlled landfill in Mexico City. The process may be adapted to the acquisition of technology in different sectors of the waste management process.
399

Irradiated graphite waste : analysis and modelling of radionuclide production with a view to long term disposal

Black, Greg January 2014 (has links)
The University of Manchester Greg BlackThesis submitted for the degree of Doctor of EngineeringIrradiated Graphite Waste: Analysis and Modelling of Radionuclide Production with a View to Long Term Disposal23rd June 2014The UK has predominantly used graphite moderator reactor designs in both its research and civil nuclear programmes. This material will become activated during operation and, once all reactors are shutdown, will represent a waste legacy of 96,000 tonnes [1]. The safe and effective management of this material will require a full understanding of the final radiological inventory. The activity is known to arise from impurities present in the graphite at start of life as well as from contamination products transported from other components in the reactor circuit. The process is further complicated by radiolytic oxidation which leads to considerable weightloss of the graphite components. A comprehensive modelling methodology has been developed and validated to estimate the activity of the principle radionuclides of concern, 3H, 14C, 36Cl and 60Co. This methodology involves the simulation of neutron flux using the reactor physics code WIMS, and radiation transport code MCBEND. Activation calculations have been performed using the neutron activation software FISPACT. The final methodology developed allows full consideration of all processes which may contribute to the final radiological inventory of the material. The final activity and production pathway of each radionuclide has been researched in depth, as well as operational parameters such as the effect of changes in flux, fuel burnup, graphite weightloss and irradiation time. Methods to experimentally determine the activity, and distribution of key radionuclides within irradiated graphite samples have been developed in this research using a combination of both gamma spectroscopy and autoradiography. This work has been externally validated and provides confidence in the accuracy of the final modelling predictions. This work has been undertaken as part of the EU FP7 EURATOM Project: CARBOWASTE, and was funded by the Office for Nuclear Regulation.
400

The effect of legislation on informal waste salvaging and salvagers on official landfill site : the case study of Weltevreden (Polokwane)

Thaba, Makgafela Richard 01 August 2012 (has links)
M.A. / In present-day society, solid waste can no longer be treated as a non-valuable resource. Municipal waste produced from residential and commercial sources has become an economic resource for the poor on landfill sites. Urban poor, rural-urban migrants and urban-urban migrants are the ultimate symbol of the informal economy on landfill sites. These migrants have identified waste as an economic resource to extract a livelihood. In their presence on landfill sites, South Africa has introduced waste management policies which endorse the notion of sustainable development. Sustainable development is the notion through which South Africa shapes and parallels its environmental directive to avoid destruction and depletion of natural resources. Sustainable development is a theoretical framework adopted by this study to evaluate the effect of legislation on informal waste salvagers and waste salvaging. Waste salvaging is often frowned upon and neglected by local municipal authorities who are constitutionally mandated to ensure preservation of natural resources. Amongst other things, local municipalities need to recreate economic opportunities and curb the unemployment rate. Furthermore, South African municipalities deliberated during the tabling of the Polokwane Declaration to reduce waste disposal by 50% in 2012 through waste recycling and waste minimisation. In the absence of employment opportunities, local municipalities in South Africa are continually faced with the dilemma of incorporating informal waste salvaging into their waste management directives. This study uses Weltevreden landfill site in Polokwane as a case study to evaluate the effects of legislation on informal waste salvaging. A waste management and sustainability framework towards career waste salvagers was developed as a paradigm to incorporate elements of sustainable livelihood approach. The framework allowed the study to comprehend the synergy and the discords that waste management directives in South Africa unravel on informal waste salvaging. Furthermore, this led to the procreation of a model to unlock the economic potential of waste in South African municipalities. The model recognises the elements of waste management directives such as National Environmental Management Act, 1998 (Act No.107 of 1998) and National Environmental Management: Waste Act, 2008 (Act No. 59 of 2008). Despite that, the model resonates on the promulgations made in the Waste Act, 2008 (Act No. 59 of 2008) on informal waste salvaging. This study intends to evaluate the extent to which contemporary waste management directives in South Africa support waste salvaging within the three pillars of sustainable development, namely economic, social and environmental. However, this research hypothesises that waste management directives in South Africa fail to support the three pillars of sustainable development. In light of the hypothesis, this research has identified waste salvagers, waste Thaba Makgafela Richard iii management officials and the public as instrumental respondents to evaluate perceptions and challenges linked to the informal waste economy. A desktop review of available regulatory instruments informed recommendations and the model procreated in this study. The key lessons are highlighted and followed in Chapter 7 which provides analytical conclusions and recommendations for all the chapters.

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