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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

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

Prawiradinata, Rudy Soeprihadi, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xvii, 264 p.; also includes graphics, maps (some col.) Includes bibliographical references (p. 236-244). Available online via OhioLINK's ETD Center
12

Composting as a tool for waste management in Hong Kong /

Cheung, Wai-ping, Clara. January 2000 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2000. / Includes bibliographical references.
13

Avfallsminimering av fraktionen brännbart i IKEA Göteborg

Svensson, Ellen, Hedlund, Frida January 2008 (has links)
<p> </p><p>IKEA of Sweden decided to set a target to keep the amount of waste low, by minimizing the amount of combustible waste to 8% of the total waste amount. IKEA Gothenburg has been having troubles with the target, since their amount of combustible waste has been twice and trice as much as the goal.</p><p>Research have been done by interviews, questionnaire, random controls in the recycling area, IKEA’s own environmental education (E-learning) and observations of the everyday work. These researches have lead to a couple of suggestions and ideas.</p><p>Issues that have been discussed is mainly the possibilities of changing and improving of the recycle area, engagement within the management as well as the staff, responsibility distribution and to make the profits in economics and environment visible.</p><p> </p> / <p> </p><p>IKEA Sverige har satt upp mål om att hålla avfallsnivån så låg som möjligt, genom att andelen brännbart avfall maximalt får vara 8% av den totala avfallsmängden. IKEA Göteborg har haft problem, då halten av deras brännbara avfall har legat på det dubbla respektive tredubbla i de båda varuhusen.</p><p>Genom en grundlig undersökning, med hjälp av intervjuer, enkäter, stickprovskontroller i ÅVC, miljöutbildning (E-learning) samt observationer av det dagliga arbetet har en rad förslag och slutsatser dragits. Bland annat diskuteras möjligheterna till förändrat och förbättrat upplägg i ÅVC, engagemang hos ledning och personal, ansvarsfördelning, utbildning samt synliggörning av ekonomiska och miljömässiga vinster.</p><p> </p>
14

Temperature and physical modelling studies of open windrow composting

Irvine, Richard John January 2002 (has links)
There is a growing demand for sustainable forms of waste management due to both legislative pressures (e.g. the European Union Landfill Directive (99/31/EC)) and increasing public awareness of environmental issues. Composting of biodegradable waste materials to produce a stabilized beneficial multi-functional product (compost) is being widely promoted. Currently, the most popular method of composting is the open windrow method, whereby the mixed and shredded feedstocks are arranged in long rows termed windrows and turned on a regular basis. During the process the waste material is subject to aerobic exothermic microbial decomposition. Commercial composting operations suffer from the problem that much of the processing is performed using empirical approaches. Improved understanding of the composting process based on scientific methodology is required to allow composting to develop its potential as an economic, safe and reliable method of sustainable waste management. This study used a series of large scale windrow-based seasonal field trials employing urban green waste as a feedstock, to investigate in unprecedented detail the temperature trends and patterns of behaviour within such structures. In addition physical-chemical profiling was undertaken. It demonstrated that windrow temperature development is not uniform in either a spatial or temporal sense. Temperature variation is a key feature of composting. All regions of typical windrows exhibited thermophilic and mesophilic temperature zones throughout the composting process. There was little seasonal variation. Sustained high temperatures were most widespread in the core regions at a height of around lm. Thus, these areas should not be favoured during temperature assessment to avoid bias results. It was demonstrated that current methods of temperature assessment are inadequate. It is suggested that greater numbers of data points are collected at varying positions and instead of simply calculating overall mean temperature that individual trends are plotted. The use of temperature frequency distribution histograms and cumulative temperature plots is additionally advised. Increased windspeed (greater than approximately 15MPH) was demonstrated to be a major factor preventing the development and sustaining of thermophilic temperatures within windrows. It is recommended that commercial composters routinely assess windspeed and direction. Changes in organic matter content, bulk density and pH provided an indication of the composting process in the long term but lacked the sensitivity of temperature measurement. Surveying using electronic tacheometry allowed changes in windrow shape and volume to be assessed. The field trial data allowed a novel physical compost model to be developed, based upon open windrow composting of urban green waste. Existing models are based on in-vessel composting systems and are technically flawed in certain key aspects. The model successfully simulated the initial stages of windrow composting, which was proven by experimentation and comparison with field trial data. The use of low level internal feedstock heating was demonstrated to be a viable method of stimulating natural enhanced microbial activity. A non- insulated model windrow and the employment of an environmental simulation system allowed the natural relationship between windrow and external environment to be modelled. The importance of such a model to the compost scientist and waste manager is highlighted. The study showed that it is possible to successfully physically model the open windrow composting process.
15

Waste policy formulation and implementation : recycling and landfill

Greaves, Christopher January 1994 (has links)
This thesis considers recycling as one option to improve the environmental performance of industry in the UK. A systems approach is used to identify objectives and capabilities of legislative and industrial agencies and to analyse issues in the broad context of waste policy formulation and implementation which spans both constituencies. It is shown that regulatory change to empower industrialists as decision takers is limited by a shortage of recycling infrastructure in the UK. Although well resourced firms are developing progressive waste policies in house, other firms are less well equipped to respond to regulatory pressures in a manner that is congruent with legislative objectives. An innovative option to develop recycling facilities for construction wastes at a landfill site is assessed, considering the roles of construction firms, skip hauliers and waste managers. An investigation is conducted into the practices employed by construction firms that influence wastes arising and likely changes to such practices. It is shown that pressures on construction firms are leading to some improvements to waste streaming that favour the recycling option. A spatial model of landfill catchment is used to estimate the elasticity of the volume of a given waste type delivered to a landfill site with respect to prices charged at the site and competing facilities. The option to recycle a substantial fraction of construction waste is compared with the null option of continuing to landfill waste without pre-treatment using a comparative cost benefit model. This model shows that, in the case of construction waste, benefits due to extending the working life of a landfill pit can be more significant than revenue effects for waste managers. Whether these benefits justify the costs of recycling is shown to be dependent on characteristics of particular landfill sites and
16

Towards the sustainable management of electronic waste in Nigeria: South Africa as a model

Okukpon, Irekpitan January 2015 (has links)
Includes bibliographical references / The trade in and management of electronic waste in Nigeria is significant because of the volumes of e-waste generated from second-hand electrical and electronic equipment (EEE) imports. Current and future e-waste discourse advocate the need for, not only an effective legislative approach, but also a sustainable approach towards e-waste management, best encapsulated through a concept known as the 'Extended Producer Responsibility (EPR)' approach. The EPR approach, which is based on the Polluter Pays Principle (PPP) places legal, financial, informative and physical(including environmental) responsibility on producers of EEE, from 'cradle-to-cradle.'The thesis groups this classification into a general term - the 'EPR Matrix,' which is utilised throughout the thesis to analyse the realistic implementation and enforcement of these responsibilities on a producer in a developing country context. Although the shipment of e-wastes between developed and developing countries is regulated under the Basel Convention 1989 and the Bamako Convention 1991, both treaties, however, do not prohibit it. The efforts of Conference of Parties (CoP) to both Conventions reveal a cognizant change in perception which is aligned with the ideals of the EPR approach to e-waste management. The realistic implementation of this approach in a developing country context is investigated, because the importer, rather than the producer is the key actor in the EEE chain. The identification of this circumstance requires that the EPR approach be extended to include the importer and other actors in the EEE chain, sharing applicable responsibilities proposed by the EPR Matrix. The thesis explores the legitimacy of this premise, by evaluating the relative success of mandatory and voluntary EPR schemes on e-waste in South Africa. Although empirical investigation reflected in the thesis reveals that voluntary industry approaches on e-waste are effective and complementary to the regulatory model, this thesis also identifies a three-tier voluntary model for effective e-waste management in South Africa, and the scope of its application. Current e-waste legislation in Nigeria reflects the adoption of the EPR approach, but in essence, the provisions are ineffective, with the absence of requisite institutions to implement its provisions. This thesis suggest that Nigerian e-waste legislation be reconsidered, with a formalization of informal e-waste markets to reflect a more resolute approach towards illegal e-waste imports and management. The certainty of a successful, and effective EPR approach in Nigeria requires a synergy of both voluntary and mandatory approaches to e-waste in that jurisdiction, and an extension of the EPR concept to include other stakeholders in industry - producers, importers, retailers, consumers and government. This thesis thus recommends the adoption of both voluntary and mandatory approaches to e-waste management in Nigeria, including an institutionalized approach, which requires the establishment of collection centres for e-waste recycling, the establishment of an EEE registry/database and proper regulation of the informal sector.
17

An assessment of the potential for waste minimisation in small and medium size enterprises in South Africa

Coleman, Ann E January 1994 (has links)
Against a background of a chemical engineering degree and a few years of industrial experience, I undertook this M.Sc. degree with the conviction that chemical engineering skills have a unique role to play in addressing environmental problems of pollution generated by industrial activity. Moreover, given that, of industrial activity, it is chemical processing industries (CPI) and mining industries which are the major contributors to generation of waste, hazardous waste in particular, it is appropriate that the chemical engineering profession, which populates such industry activities, should assume such responsibility. In response to increasingly vociferous demands for more stringent environmental control over industrial activity, and regulatory compliance with stricter constraints on emissions of pollutants, there is a tendency to rely on readily available end-of-pipe solutions to resolve environmental management problems. This strategy is embodied in current practices in South Africa at effluent treatment- and landfill disposal facilities. Yet this is a costly solution in the long term, with implications for increasing operating costs, investment costs for development of new facilities, as well as closure and potential liability costs for old facilities. Furthermore, this strategy fails to address problems of resource depletion and the potential for resource recovery from materials considered to be "waste". Waste minimisation offers an alternative waste management strategy which seeks to reduce the generation of waste before end-of-pipe management is required, and to recover resources for reuse, thereby reducing resource consumption. The Department of Environment Affairs in the South African government has recommended that there should be research in the application of waste minimisation. While clearly there is a need for fundamental research into particular technological problems (such research is being undertaken at some institutions), the approach I adopted was to investigate potential for effecting meaningful waste minimisation solutions using procedures and techniques which constitute popular waste minimisation assessment methodologies. I focused specifically on small and medium scale industry operators which traditionally do not employ chemical engineering skills and which need a practical tool to improve in-house environmental management capability.
18

Waste farm: a productive landscape for integrated waste management

Mashazhu, Mabasa January 2015 (has links)
In 2010 the city of Cape Town partnered with the Department of Environmental Affairs to initiate a project to investigate and evaluate the possible re-opening and licensing of Historic and Old landfill sites. The project to reassess these landfill sites is due to the fact that the three main operating landfill sites in Cape Town are nearing capacity. This calls for the city to re-imagine its waste management infrastructure. Meanwhile, within the urban areas of Cape Town, there exists a network and constellations of informal waste pickers working in conjunction with buy-back centres and recyclers to form an economically, environmentally and socially sustainable solution that diverts volumes of recyclable waste from landfills. These informal waste pickers contribute to filling in a gap within the formal recycling system but there is no infrastructure supporting these individuals on whom the formal recycling industry depends on. Most of the waste pickers sleep 'on the streets' with little access to amenities such as water, toilets and washing facilities. The spaces they occupy/sleep make it hard to store their pickings and hence they are forced to sell as soon as they collect. It also forces them to make multiple trips to the buy-back centres whom they are always at the mercy of, particularly when the ever changing price of recyclable waste is low. This project aims at creating a productive landscape that uses waste as a vehicle to enhance the livelihoods of informal waste pickers and encourage local communities to see the economic and environmental value of recycling waste. By providing secure storage and sorting, safe/hygienic sleeping and cleaning spaces coupled with social and productive areas; the project seeks to unlock the potential of recycling using a suitable architectural intervention that is self-sustaining.
19

Implementation of waste to energy systems in metropolitan America

January 2012 (has links)
0 / SPK / specialcollections@tulane.edu
20

The environmental politics of the international waste trade

Strohm, Laura A., January 1991 (has links)
Thesis (Ph. D.)--Fletcher School of Law and Diplomacy, 1991. / VIta. Includes bibliographical references (leaves 220-231.).

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