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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.
191

The independent trash collectors

Miller, Larry D. January 1971 (has links)
This thesis is a study of the occupational group consisting of the independent trash collectors in Center Township of Delaware County, Indiana. It represents an attempt to discover who the individuals are who comprise this group and what characteristics they have as trash collectors.This thesis explores the attitudes of the independent collectors toward the public, their attitudes regarding the public’s conception of them, and the collectors’ attitudes toward their work. The views these men hold regarding their future and the future of their business are also examined. This thesis also discusses the equipment which the collectors own and use and surveys the present situation and future developments likely in the trash business.
192

Solid waste management strategy in Hong Kong country parks /

Chan, Ping-kwong, Richard. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references (leaves 78-80).
193

The characteristics and impacts of landfill leachate from Horotiu, New Zealand and Maseru, Lesotho

Mohobane, Thabiso. January 2008 (has links)
Thesis (M.Sc. Environmental Science)--University of Waikato, 2008. / Title from PDF cover (viewed April 24, 2009) Includes bibliographical references (p. 138-147)
194

Environmental health policy implementation in Hong Kong a study of cleansing services in the Urban Services Department /

Woodhead Loo, Wing-ping, Marina. January 1986 (has links)
Thesis (M.Soc.Sc.)--University of Hong Kong, 1986. / Also available in print.
195

"Skarrelling" : a socio-environmental history of household waste in South Africa

King, Giorgina F. J. 04 1900 (has links)
Thesis(MA)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: This study excavates a century’s worth of the history of household waste in South Africa, from 1890-1996. It shows that waste history is entangled with histories of disease and poor sanitation, advances in technology, the impact of war, environmental concerns and – perhaps above all – shifting socio-economic circumstances. Using a socio-environmental analytical framework, this analysis of waste history unearths empirical archival data and oral testimony, to contextualise themes of gender, race, class and nationalism in order to place rubbish within the wider historical debates in South Africa. This study uses Rubbish Theory and Broken Windows Theory as well as concepts of “Othering” and the “Sanitation Syndrome” to explore the role of waste in the construction of racial identities and perceptions. This thesis shows that Apartheid should not be seen as a watershed within this waste history, but rather as a continuation of colonial ideas of cleanliness that helped to perpetuate racist stereotypes. This study argues that the lack of waste services in “locations” during this time helped to contribute to the perception of the urban African as the unsanitary Other. The state and civic societies fostered gender roles, which (coupled with wartime nationalist propaganda) helped in shaping waste behaviour promoted by the National Anti-Waste Organisation (NAWO) during the Second World War (WWII). In the years after WWII, the threats of wartime shortages and enthusiastic solutions suggested to municipalities to “end the waste problem” were thwarted by the spread of the landfill as an even more convenient disposal method. The implementation of Apartheid, especially the Group Areas Act (No 41 of 1950) and the rise of consumer society, led to increasingly divergent experiences of waste for urban Africans and whites. The thesis uses a case study of the Devon Valley Landfill community outside of Stellenbosch. This ethnographic history explores notions of the “Subaltern” in order to give this history a human face. The diachronic analysis of this community offers a lens into ideas of “ordentlikheid” (decency), “weggooi mense” (throwaway people) and how these waste-pickers experience the environment in which they live. / AFRIKAANSE OPSOMMING: Hierdie studie grawe ’n eeu se geskiedenis van huishoudelike afval in Suid-Afrika op, van 1890-1996. Dit toon dat die geskiedenis van afval verweef is met geskiedenisse van siekte en swak sanitasie, tegnologiese vooruitgang, die impak van oorlog, omgewingskwessies en – dalk bowenal – veranderende sosio-ekonomiese omstandighede. Deur middel van ’n sosio-omgewings-analitiese raamwerk ontgin hierdie analise empiriese argiefdata en mondelingse getuienis om temas van geslag, ras, klas en nasionalisme te kontekstualiseer ten einde afval binne die breër historiese debatte in Suid-Afrika te plaas. Die studie gebruik Afval-teorie en Gebreekte Vensters-teorie sowel as begrippe van “Othering” en die “Sanitasie-sindroom” om die rol van afval in die totstandkoming van rasse-identiteite en -persepsies te ondersoek. Die tesis toon dat Apartheid nie as ’n waterskeiding in hierdie afval-geskiedenis gesien moet word nie, maar eerder as ’n voortsetting van koloniale idees oor higiëne wat gehelp het om rasse-stereotipes te perpetueer. Die studie argumenteer dat die gebrek aan afvalverwyderingsdienste in “lokasies” in die tyd bygedra het tot die persepsie van die stedelike Afrikaan as die onhigiëniese Ander. Die staat en burgerlike samelewings het geslagsrolle gekweek, wat (tesame met oorlogtydse nasionalistiese propaganda) gehelp het met die vestiging van afval-gedrag wat bevorder is deur die National Anti-Waste Organisation (NAWO) gedurende die Tweede Wêreldoorlog. In die jare na dié oorlog is die bedreigings van oorlogtydse tekorte en die entoesiastiese oplossings wat vir munisipaliteite aanbeveel is om die “afvalprobleem te beëindig”, gefnuik deur die toenemende gebruik van stortingsterreine as ’n selfs geriefliker afvalverwyderingsmetode. Die implementering van Apartheid, veral die Groepsgebiedewet (No. 41 van 1950) en die opkoms van die verbruikersamelewing, het gelei tot toenemend uiteenlopende ervarings van afval onder stedelike Afrikane en wit mense. Die tesis maak gebruik van ’n gevallestudie van die gemeenskap van die Devonvallei-stortingsterrein buite Stellenbosch. Hierdie etnografiese geskiedenis verken denkbeelde van die “Ondergeskikte” om ’n menslike gesig aan die geskiedenis te gee. Die diakroniese analise van die gemeenskap is ’n venster op idees van “ordentlikheid”, “weggooimense” en hoe hierdie afvalontginners die omgewing waarin hulle woon, beleef.
196

Refuse collection management practices in the Buffalo City Municipality

Damane, Mcebisi January 2012 (has links)
The ineffective and inefficient management and collection of municipal solid waste is a significant problem in cities of many developing countries. South Africa as a developing country is also faced with the same problem. Buffalo City Municipality with its fast growing urban population is not immune from the problem. Due to continuing population growth, urbanisation, industrialisation and higher consumption levels which started after the demise of the previous legislations which stifled the advancement of black communities, the generation and management of municipal solid waste in developing countries is likely to worsen. The uncollected waste and rampant littering generates pollution and poses risks to human health and the environment. Regulations guiding the treatment and the disposal of waste are not followed to the letter by authorities. There are no measures in place to ensure that the environment is sustained, and even if there are they are not fully implemented. This affects municipalities negatively in various aspects. Tourism that is known to boost ailing and weak local economies is affected. Properties are devaluated and potential developers turn their backs on municipalities that are not well managed. It is the low-income communities that suffer the brunt of the inefficiency and poor service delivery. This status quo is not acceptable eighteen years after the attainment of democracy and the adoption of the Constitution in South Africa. This study analyses the challenges and factors that cause Buffalo City Municipality (BCM) not to deliver services efficiently and successfully in respect of waste management. It also attempts to check alternatives and solutions as gathered from other cities in a similar predicament. Municipalities are encouraged to adopt Local Economic Development (LED) principles and establish public- public partnerships and private- public partnerships thereby utilizing communities in refuse collection and waste management.
197

Techno-economic analysis of a gasification system using refuse-derived fuel from municipal solid waste

Adefeso, Ismail Babatunde January 2017 (has links)
Thesis (Doctor of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2017. / The search for alternatives to fossil fuel is necessary with a view to reducing the negative environmental impact of fossil fuel and most importantly, to exploit an affordable and secured fuel source. This study investigated the viability of municipal solid waste gasification for a fuel cell system. Potential solid fuels obtained from the study in the form of refuse-derived fuel (RDF) had high heating value (HHV) between 18.17 MJ/Kg - 28.91 MJ/Kg with energy density increased from 4142.07 MJ/m3 to 10735.80 MJ/m3. The molecular formulas of RDF derived from Ladies Smith drop-off site, Woodstock drop-off site and an average molecular formula of all thirteen municipal solid waste (MSW) disposal facilities were CH1.43O1.02, CH1.49O1.19, and CH1.50O0.86 respectively. The comparative ratios of C/H were in the range of 7.11 to 8.90. The Thermo Gravimetric Analysis showed that the dehydration, thermal decompositions, char combustions were involved in the production of gaseous products but flaming pyrolysis stage was when most tar was converted to syngas mixture. The simulation of RDF gasification allowed a prediction of the RDF gasification behaviour under various operating parameters in an air-blown downdraft gasifier. Optimum SFR (steam flowrate) values for RDF1, RDF2 and RDF3 were determined to be within these values 2.80, 2.50 and 3.50 and Optimum ER values for RDF1, RDF2 and RDF3 were also determined to be within these values 0.15, 0.04 and 0.08. These conditions produced the desired high molar ratio of H2/CO yield in the syngas mixture in the product stream. The molar ratios of H2/CO yield in the syngas mixture in the product stream for all the RDFs were between 18.81 and 20.16. The values of H2/CO satisfy the requirement for fuel cell application. The highest concentration of heavy metal was observed for Al, Fe, Zn and Cr, namely 16627.77 mg/Kg at Coastal Park (CP), 17232.37 mg/Kg at Killarney (KL), 235.01 mg/Kg at Tygerdal (TG), and 564.87 mg/Kg at Kraaifontein (KF) respectively. The results of quantitative economic evaluation measurements were a net return (NR) of $0.20 million, a rate of return on investment (ROI) of 27.88 %, payback time (PBP) of 2.30 years, a net present value (NPV) of $1.11 million and a discounted cash flow rate of return (DCFROR) of 24.80 % and 28.20 % respectively. The results of the economic evaluations revealed that some findings of the economic benefits of this system would be viable if costs of handling MSW were further quantified into the costs analysis. The viability of the costs could depend on government responsibility to accept costs of handling MSW.
198

The attitudes of the residents and the municipality of Thulamahashe in the Limpopo Province of South Africa towards waste management

Mathebula, N. P. January 2006 (has links)
Thesis (MPA.) --University of Limpopo, 2006 / Refer to the document
199

Contract and strategic network design for reverse production systems

Pas, Joshua W. January 2008 (has links)
Thesis (Ph. D.)--Industrial and Systems Engineering, Georgia Institute of Technology, 2008. / Committee Co-Chair: Ammons, Jane C.; Committee Co-Chair: Realff, Matthew J.; Committee Member: Griffin, Paul M.; Committee Member: Peoples, Robert; Committee Member: Thomas, Valerie.
200

Plastic waste gasification using a small scale IR reactor : experimental and modelling analysis

Guyemat Mbourou, Sarah Marielle January 2016 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016. / The generation of municipal solid waste has increased significantly due to the exponential population growth and it has become a global issue. Gasification technology, an alternative method for waste treatment is a thermochemical process where carbon-based material are exposed to an environment deprived in oxygen, was used for this project. The aim of this thesis is to study the gasification of plastic waste which is a potential alternative energy source using infrared heaters. To achieve this goal, fundamental studies have been numerically and experimentally conducted for an infrared gasifier and subsequently establishing the temperature profile for gasification using a small scale reactor. A detailed study on low density polyethylene was conducted using Infrared Spectrometry and thermal decomposition techniques such as Thermogravimetry and Differential Scanning Calorimetry were performed to establish the temperature at which plastic pellets sample used for this research gasify. The gasification behaviour of pelletized low density polyethylene (plastic pellets) was tested and three case studies were done to evaluate the most suitable temperature profile for the reactor to gasify the low density polyethylene at high temperature for less amount of time. Subsequently, the reactor model was simulated and results validate the use of reactor at an optimum temperature of 800 °C for a gasification process with less residue content. The reactor designed for this research is fully functional and validates the temperature behaviour predicted during simulation. The experimental results show infrared heaters are suitable for gas production using this gasification process.

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