Since the 1990s, Municipal Solid Waste Management (MSWM) has shifted to a more comprehensive approach with an emphasis on managing Municipal Solid Waste (MSW) through the whole process from generation to disposal. Meanwhile, developing countries started to alter their ways of managing wastes and engage in more efforts on waste diversion. Due to their shortage of both resources and expertise, developing countries usually refer to and learn from developed countries’ experiences in MSWM to improve their own practices. How and to what extent these experiences are helpful for developing countries remains inconclusive because significant differences are present among MSWM systems in different countries. These differences do not simply reflect the variations in regulations and resource allocation; more importantly, they reflect the variations in the underlying connections between MSWM and other social, economic, demographic, and technological conditions. Therefore, a systematic examination is needed to enhance the understanding of these differences, the reasons for these differences, and the priorities that need to be stressed in order to improve waste diversion in a particular case. A systematic model, as the framework for the comparison in this thesis, is proposed to illustrate MSMW systems. Based on the model, this thesis compares and contrasts two cases, the Regional Municipality of Waterloo (RMOW) in Canada and Dalian City in China, at multiple levels: overall stage, system components, system structures, and interactions. The results show that Dalian, compared with the RMOW, has less sufficient capacities for waste planning and implementation. Challenges in MSWM are associated with higher density of residences, difficulties in managing informal profit-driven recycling activities, insufficient and unreliable treatment capacity, insufficient multi-agent dialogues and cooperation both within the government and between the public and private sectors, and less specific, program-based public education. The majority of participants in the RMOW are more self-motivated as opposed to the majority in Dalian who are motivated more by compensations. Based on the comparison, implications and suggestions in several aspects concerning waste planning are discussed. From the systematic perspective, to improve waste diversion in Dalian requires collaborative efforts of multiple agents. The key aspect is to strengthen the relatively incompetent component in the system to improve the capacities for waste service and treatment, which are contingent on the development of waste industries. In Dalian, waste diversion should begin with limited types of wastes and gradually expand the scope, and new programs should be designed based on the existing system with cooperation of the informal sector. Meanwhile, cooperation among governmental divisions and between public and private sectors need to be promoted by encouraging multi-agent dialogues and improving information transparency. Program promotion also needs to be more specific in instructions and to address both pro- environmental attitudes and service quality and convenience. Finally, scavenging at landfill sites should be discouraged in order to protect scavengers from the detrimental working environment.

Stainless steel – zirconium alloys were developed by the US Department of Energy Laboratories as metallic waste forms for noble metal fission products. This thesis evaluates iron–zirconium–rhenium alloys to establish a technical basis for using metal waste form alloys for technetium-99 immobilization. Rhenium is used as a surrogate for Tc-99 since Tc is not naturally available and Re is metallurgically similar to Tc. The iron-zirconium system has two eutectic compositions, Fe-15 wt % Zr and Zr- 16 wt% Fe. Ten test samples were successfully cast in yttrium oxide crucibles at 1600°C, half near each eutectic composition, with Re amounts varying from 2.5 to 12.5 weight percent. A scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDS) capability was employed to determine the phase structure and phase composition of each sample. Iron rich samples were found to form up to three phases, with the rhenium content favoring the intermetallic phases: 1) an Fe solid solution phase, 2) an FeZr2-type intermetallic with 11 wt % or less Re, and 3) a second intermetallic with about 18 wt % Re. Zirconium rich samples formed as many as five distinct phases: 1) a Zr solid solution phase, 2) a Zr3Fe-type intermetallic with as much as 13 wt% Re, 3) a rhenium-zirconium intermetallic, 4) another Fe-Zr intermetallic with very little Re, and 5) a Fe-Re intermetallic. Potentiostatic and potentiodynamic electrochemical tests were performed using sulfuric acid to evaluate the corrosion resistance of each sample. These tests found that the zirconium rich samples were very corrosion resistant but became increasingly susceptible at higher rhenium concentrations. The iron rich samples were not very resistant to corrosion under the test conditions; there was no notable trend in corrosion behavior related to the introduction of rhenium.

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Stainless steel - zirconium alloys were developed by the US Department of Energy Laboratories as metallic waste forms for noble metal fission products. This thesis evaluates iron-zirconium-rhenium alloys to establish a technical basis for using metal waste form alloys for technetium-99 immobilization. Rhenium is used as a surrogate for Tc-99 since Tc is not naturally available and Re is metallurgically similar to Tc. The iron-zirconium system has two eutectic compositions, Fe-15 wt % Zr and Zr- 16 wt% Fe. Ten test samples were successfully cast in yttrium oxide crucibles at 1600°C, half near each eutectic composition, with Re amounts varying from 2.5 to 12.5 weight percent. A scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDS) capability was employed to determine the phase structure and phase composition of each sample. Iron rich samples were found to form up to three phases, with the rhenium content favoring the intermetallic phases: 1) an Fe solid solution phase, 2) an FeZr2-type intermetallic with 11 wt % or less Re, and 3) a second intermetallic with about 18 wt % Re. Zirconium rich samples formed as many as five distinct phases: 1) a Zr solid solution phase, 2) a Zr3Fe-type intermetallic with as much as 13 wt% Re, 3) a rhenium-zirconium intermetallic, 4) another Fe-Zr intermetallic with very little Re, and 5) a Fe-Re intermetallic. Potentiostatic and potentiodynamic electrochemical tests were performed using sulfuric acid to evaluate the corrosion resistance of each sample. These tests found that the zirconium rich samples were very corrosion resistant but became increasingly susceptible at higher rhenium concentrations. The iron rich samples were not very resistant to corrosion under the test conditions; there was no notable trend in corrosion behavior related to the introduction of rhenium.

Thesis (Ph.D.) -- University of Texas at Arlington, 2009.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 213-216). Also available in electronic version. Access restricted to campus users.

Titel: Waste Management – Förbättringsförslag av återvinningsprocessen inom hemelektronikbranschen. Bakgrund: I en bransch som kännetecknas av snabb teknologisk utveckling är det viktigt att se till att de produkter som kommer ut på marknaden också tas om hand på ett bra sätt i slutet av sitt funktionella liv. Hur ser återvinningsprocessen hos företagen ut idag och vad kan göras för att minska de växande problem som framkommer i samband med den ökade konsumtionen? Genom att granska fenomenet Waste Management avser uppsatsen angripa slöseri i logistikflödet och finna förbättringar av dagens återvinningsprocess av uttjänta hemelektronikprodukter. Syfte: Uppsatsens syfte är att kartlägga återvinningsprocessen inom branschen för hemelektronik i syfte att identifiera potentiella förbättringsåtgärder med det samhällsekonomiska målet att uppnå ett större returflöde i logistiksystemet ur ett företagsperspektiv. Metod: Studien utgår från en kvalitativ forskningsmetod som gjorts baserat på en flerfallsstudie. Primärdata har samlats in genom semi-strukturerade besöksintervjuer och asynkrona individuella intervjuer online utifrån ett bekvämlighetsurval. Studien intar ett positivistiskt synsätt och det vetenskapliga angreppssättet är abduktivt. Analysen utgörs enligt en mönsterjämförelse med avseende på produkttyper, kompensation och information till kund. Slutsats: Författarna kommer efter analys av funktionsflödesschema och mönsterjämförelse fram till ett antal punkter för förbättring vilka kan leda till ökad andel återvunna EOL-produkter. Dessa är; införande av ett fast returcenter, omhändertagande av ett större produktsortiment, föra statistik över returer, tydligare information till kund och kompensation för inlämnade produkter. Författarna kommer även fram till att det råder stora skillnader i hur man i dagsläget arbetar med Waste Management inom de olika företagen, där vissa företag är mer ambitiösa än andra. Företagen har mycket att lära av varandra och inom samtliga studerade företag finns något att förbättra.

The rapid growth of urban areas in Malaysia has led to an increase in the generation and complexity of its municipal solid waste. The amount of municipal solid waste generated is estimated to be 8 million tonnes per year by the end of 2000. Realising the problem, this research was conducted to analyse quantitatively experiences learned from the United Kingdom (UK) upon the success through their municipal solid waste management system set-up which includes enforcement, legislation, economic instruments, education, institutions involved and other related issues. In order to achieve that, comparative studies were conducted between United Kingdom and Malaysian practices which included selected local councils, namely Dundee City Council (DCC) in the UK and Majlis Perbandaran Petaling Jaya (MPPJ) and Dewan Bandaraya Kuala Lumpur (DBKL) both in Malaysia to identify and how to overcome the problems. Apart from the above objectives, this research suggests that: The most effective environmental solution is to reduce the generation of waste through reduction; Where further reduction is not practicable, products and materials can sometimes be used again, either for the same or a different purpose that is through re-use; Failing to do that, value should be recovered from waste, through recycling, composting or energy recovery from waste; Only if none of the above offer an appropriate solution should waste be disposed of This is the best hierarchy for Malaysia to adapt in its future municipal solid waste management strategy. In conclusion, this research showed that Malaysia's municipal solid waste management system and strategy have to be developed in term of its legislation and policy, the enforcement system, guidelines and target to be achieved and education as the key in developing awareness and knowledge.

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

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