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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.
51

Sustainability in municipal solid waste management in Bamenda and Yaounde, Cameroon

Achankeng, Eric January 2004 (has links)
In Cameroon, and most other developing countries, the problem of inefficient municipal solid waste management ( MSWM ) is endemic. This is easily identified by persistent heaps of uncollected waste found on street sides or ubiquitous illegal dumps. This thesis examines the sustainability of MSWM in Cameroon using two contrasting city cases of Yaoundé ( 1.5m people ) and Bamenda ( 300 000 people ). As major contributions the thesis generates the much - needed basic original data, critically examines and compares the sustainability of MSWM in both cities ' systems, evaluates the environmental impacts and uses these findings to suggest valuable research, policy and strategic - planning recommendations needed to make both systems, and others in similar situations, sustainable. To achieve these goals multiple triangulated methods were used. In Bamenda, where reliable basic data are non - existent, solid waste from sampled households was collected and analysed for generation rates, quantities and characteristics. In both cities questionnaire were administered to sampled household units selected from four stratified quarters. The survey questions addressed waste management issues and sustainability indicators that were needed to study, compare and evaluate the systems within the wider concept of the waste management hierarchy. The statistical programme for social sciences ( SPSS ) computer software was used to analyse the survey results. Field observations, interviews and a review of secondary sources complemented the data. New findings show that Bamenda city generates 120 - 160 tonnes of municipal solid waste daily ( 0.40-0.54 kg per capita ), 76 % of which is biodegradable and 24 % non - biodegradable. About 90 % of all solid waste comes from households. Bamenda Urban Council ( BUC ) regularly covers only 1 / 20th of the city area and collects and transports 20 - 30 tonnes of waste from its skips, accounting for only 17 - 25 % of the total daily waste generation. The waste is disposed of at an uncontrolled dump on the Mezam River flood plain. The citizens illegally dump the rest. Skips are crucial to the system but their total capacity and access are grossly inadequate ( 37m ³ over 28 sites ), with a further 465m ³ needed. Citizens move an average of 105 m to waste disposal sites. This suggests a sustainable inter - skip distance of 210 m for Bamenda city, far from the present 700 m. Yaoundé ' s daily per capita MSW generation rate is estimated at 0.79 kgs or 1200 tonnes for the entire city, three - quarters of which is biodegradable. Only one - third of the city area is regularly served with about 40 - 50 % ( ~ 540 tonnes ) of the waste collected and disposed of at the sanitary landfill on the Nfoulou River valley. Total available skip capacity is 1440m ³ with 3048m ³ lacking. The primary waste disposal average distance is 87 m. Yaoundé and Bamenda cities are unique in physical conditions and status but neither is able to deal adequately with the increasing waste generation rates, quantities and varieties that are driven by rapid urban population growth, spatial expansion and improved affluence and consumption among selected groups. Yaoundé ' s management has an edge over Bamenda ' s in terms of performance rates but leaves behind five times more uncollected and illegally dumped waste than Bamenda. Though Yaoundé ' s system is private and Bamenda ' s is public, both systems apply the same conventional approach that concentrates on imported technologies while neglecting waste prevention, recycling, safe disposal, involvement and integration of citizens and other stakeholders. This limited and monopolistic approach makes the system unworkable and equally creates huge environmental and health - related problems present at all the stages of the waste management cycle. Government devolves the waste function to urban councils but centralises funds and power. Its waste policies are limited, fragmented and confusing. The garbage tax law yields only 5 % in Bamenda and 7 % in Yaoundé, making both cities rely heavily on extra financial support from Cameroon and abroad. In all, neither city in the study demonstrates sustainability in any aspects of its MSWM system. The existing systems are not sustainable. A new system based on an integrated sustainable model operated within the context of good urban governance is proposed. This model accommodates the uniqueness of cities and is recommended for other cities in the country, Africa and the developing world. / Thesis (Ph.D.)--School of Social Sciences, 2004.
52

The use of recycled concrete in construction

Fung, Wing-kun. January 2005 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
53

Analysis of chemical and physical processes during the pyrolysis of large biomass pellets /

Chan, Wai-chun Ricky. January 1983 (has links)
Thesis (Ph. D.)--University of Washington, 1983. / Vita. Bibliography: leaves 169-182.
54

Dynamics of technological innovation systems : the case of biomass energy /

Negro, Simona O. January 2007 (has links)
Univ., Diss.--Utrecht, 2007.
55

A comprehensive study of recycled concrete aggregates as a drainable base layer for pavements

Bosquez, Juan. January 2009 (has links)
Thesis (Ph.D.) -- University of Texas at Arlington, 2009.
56

Thermochemical conversion of biomass into fuels and chemicals /

Sukhtankar, Samir A. January 2003 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 104-105). Also available on the Internet.
57

Thermochemical conversion of biomass into fuels and chemicals

Sukhtankar, Samir A. January 2003 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 104-105). Also available on the Internet.
58

Characterization of cement-kiln-dust stabilized base/subbase aggregate /

Zhu, Jianhua, January 1998 (has links)
Thesis (Ph. D.)--University of Oklahoma, 1998. / Includes bibliographical references (leaves 215-221).
59

Large-scale laboratory and in-situ field tests on cemented rubber chips (rubber-soil) as pavement sub-base /

Cheung, Kwai Wah. January 2003 (has links)
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.
60

Enzymatic hydrolysis of cellulosic fiber

Rao, Swati Suryamohan. January 2009 (has links)
Thesis (M. S.)--Chemical Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Banerjee Sujit; Committee Member: Deng Yulin; Committee Member: Haynes Danny. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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