Thesis (M. Sc.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 176-181).

Thesis (M. Sc.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 77-82).

Thesis (M. Phil.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 115-120).

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 278-283). Available also in a digital version from Dissertation Abstracts.

Thesis (M.Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaf 63-64). Also available in print.

Thesis (M.P.A.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 124-126). Also available in print.

Thesis (M.S.)--State University of New York at Binghamton, Department of Geological Sciences and Environmental Studies, 2008. / Includes bibliographical references.

Poverty and unemployment in the rural areas of the Eastern Cape is forcing thousands of vulnerable people into waste picking. There is growing recognition that waste re-claimers contribute to the local economy, to public health and to environmental sustainability. However, they often face low social status, tragic living and working conditions, and little support from local governments. The waste reclaimers of the Raymond Mhlaba Municipal area are unemployed, experiencing a poorer quality of life and feeling even more socially and economically excluded from the rest of society because of the “limitations” on landfill salvaging currently. Moreover, they have developed feelings of resentment and anger that have resulted in defiant acts of trespassing and theft. This social development study highlights the implications of landfill closure for waste salvagers in Raymond Mhlaba Local Municipality. Landfilling has been the main method for municipal waste disposal in Raymond Mhlaba Local Municipality. To combat the effects of uncontrolled release of landfill gases, the uncontrolled release of leachate that may affect water quality many landfills in the Eastern Cape are being considered for close down and for rehabilitation. To consider as well is the socio-economic backlog and anticipated population growth in the province, which means that landfill salvaging will continue to be an important source of revenue for the poor and homeless. This research used observation, semi-structured one-on-one interviewing, focus group interviewing and questionnaires as well as conducted a review of waste management policy-related documents and secondary data analysis in this qualitative research to analyse the social and the economic impacts. The research found that waste reclaimers in the Raymond Mhlaba Local Municipality area disagreed with the closure of the Fort Beaufort landfill because of what the researcher assumed to be a lack of general environmental awareness and because of their vulnerability to poverty. Research findings also highlight that waste reclamation can be considered as a viable option to minimize waste at landfills and waste reclaimers have shown an increasing interest and commitment to being trained formally to continue reclamation work. This study has suggested disadvantages in rural landfill closure, without feasible alternatives. Focus must move away from extending waste collection and closing down landfills and instead improve final disposal and initiating minimisation- recycling programs as part of their strategies through the formation of waste cooperatives. This research suggests formalizing and controlling waste recovery to cater for the immediate and most basic needs of the poor. The recommendations will hopefully influence thinking about waste management policy planning and implementation in general, and be of service to furthering Raymond Mhlaba Local Municipality achieve goals of sustainable employment creation and poverty alleviation.

Made available in DSpace on 2014-10-09T12:41:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:33Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Thesis (DTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017. / The process of anaerobic digestion (AD) is one of the most cost-effective and environmentally sustainable technologies to treat wastewater in the agricultural sector. In South Africa, in some industries in the agricultural sector, such as the poultry industry in particular, slaughterhouses have the highest consumption of potable water, culminating in the production of a large quantity of high strength wastewater. This high consumption of potable water has become a concern in South Africa due to water scarcity and reduced rainfall attributed to global warming, including weather changes. Furthermore, the generation of a large volume of wastewater poses environmental pollution concerns. The wastewater from poultry slaughterhouses can be quite easily treated to a suitable quality for reuse, using various bioreactor systems that utilise low cost anaerobic digestion processes. However, as this wastewater contains a high quantity of biodegradable organic matter – with the primary pollutants being proteins, blood, fats, oil and grease (FOG) – selecting a suitable anaerobic reactor configuration (up-flow vs down-flow) plays an important role in achieving high reactor performance. In this study, both the up-flow, (i.e. Expanded Granular Sludge Bed Reactor) and the down-flow (i.e. Static Granular Static Granular Bed Reactor), were studied to quantitatively determine their performance in treating poultry slaughterhouse wastewater. Firstly, the feasibility of treating poultry slaughterhouse wastewater with an up-flow Expanded Granular Sludge Bed Reactor (EGSB) coupled with anoxic and aerobic bioreactors was investigated at an HRT of 7 (168 hr), 4 (96 hr) and 3 (72 hr) days using organic loading rates of 0.5, 0.7 and 1.0 gCOD/L.day. The averaged tCOD removal for the EGSB reactor was 40%, 57% and 55%, respectively, at the various OLRs and HRTs investigated. The overall tCOD removal of the system (EGSB-anoxic/aerobic) at high OLR of 1.0 gCOD/L.day was increased to 65%. The redundant performance of the up-flow EGSB reactor was attributed to the periodical sludge washout experienced during its operation due to high FOG and TSS concentrations in the influent. Due to the periodic sludge washout, the reactor required continuous re-inoculation resulting in the EGSB being operated for a short period (i.e. 26 days). As a result of such system deficiency, it was recommended that to improve the performance of the up-flow EGSB reactor in treating poultry slaughterhouse wastewater, a pre-treatment system – such as a Dissolved Air Floatation system (DAFs) or a FOG skimmer – is required to reduce the FOG and total suspended solids (TSS) load prior to the wastewater fed to the EGSB. This will minimise system failure and the need for a continuous re-inoculation of the system (see Appendix C for improved operation strategy of the EGSB reactor). Furthermore, a system redesign was recommended, thus the use of the SGBR. Secondly, after the EGSB system evaluation, the performance of a down-flow system (i.e. SGBR) for the new design, the following were deemed appropriate for improved system (SGBR) design: 1) reduced HRT for high wastewater treatment through-put rates; 2) the ability to adequately treat the wastewater with higher organic loading rates; and 3) reduction of the plant footprint by using a membrane filtration system (i.e. a single process unit) to effectively reduce process requirements needed for the anoxic/aerobic bioreactors (i.e. n=2 process unit) used with the EGSB. Similarly, for large-scale operations, it is advisable to have a backwash system to adequately handle declogging processes (i.e. these systems modifications were evaluated in the SGBR). The SGBR, coupled with an ultra-filtration (UF) membrane system, was then investigated for treating the poultry slaughterhouse wastewater at an HRT of 55 hrs and 40 hrs, including average OLRs of 1.01 and 3.14 gCOD/L.day, respectively. The average maximum performance of the SGBR in terms of tCOD, TSS and FOG removal was > 90% at the OLRs and HRTs investigated. The UF membrane system used as a post-treatment system further yielded a system performance improvement for tCOD, TSS and FOG of 64%, 88% and 60%, respectively. The overall performance of the combined system (SGBR and UF membrane system) in terms of tCOD, TSS and FOG removal was 98%, 99.8% and 92.4%, respectively. The highest performance for the down-flow SGBR was attributed to its ability to retain granulated sludge in the reactor while maximizing the digestion of the organic matter fed into the reactor, even at higher OLRs. Furthermore, for effective declogging, the implementation of a periodic backwash system to effectively remove dispersed fine sludge particles in the underdrain and excessive suspended solids entrapment was observed to ease the system operational deficiencies.