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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.
41

Provision of sewage services a case study of the trading fund established in the Drainage Services Department /

Hon, Chi-keung. January 1997 (has links)
Thesis (M.P.A.)--University of Hong Kong, 1997. / Includes bibliographical references. Also available in print.
42

Investigation into the denitrification of high strength landfill leachate using pine bark and raw and composted commercial garden refuse as a carbon source : column studies /

Browne, A. J. Unknown Date (has links)
Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010. / Full text also available online. Scroll down for electronic link.
43

Systems modelling of municipal solid waste collection operations /

Wilson, Bruce Gordon. January 2001 (has links)
Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references. Also available via World Wide Web.
44

Sewage wastewater management in South Africa

Eddy, Linda Joanne 06 December 2011 (has links)
M.Sc. / The South African Water Act (Act 54 of 1956) was promulgated in 1956. Section 21 of this Act required the permitting of all effluent dischargers, including sewage works. The General and Special Standards were subsequently published in the Government Gazette in 1984 in accordance with this Act, which set effluent discharge quality limits for such discharges. This was the Uniform Effluent Standard approach. However, this approach did not take into account the assimilative capacity of the receiving water, or limitations thereof. This resulted in a decrease in the water quality in the nations' water resources (DEAT 1999). The White Paper on Water Policy in South Africa was published by the Department of Water Affairs and Forestry in 1997. This paper identified this concern and suggested a change in the way water quality was managed in the country. The National Water Act (Act 36 of 1998) was subsequently promulgated in 1998, and provided the tool to effect these changes. This Act adopted the Receiving Water Quality Objectives (RWQO) approach. This approach takes into account the impacts on the receiving water as well as the impacts on other water users. This mini-thesis compared SA legislation regulating the discharge of wastewater, and more specifically sewage effluent, into the environment, by comparing it to first world legislation performing the same function. The effectiveness of the implementation of the SA legislation was also investigated. This study concluded that the promulgation of the National Water Act of 1998 (Act 36 of 1998) brought SA legislation on par with first world trends. This is an advanced piece of legislation, the effects of which are only now beginning to be felt. Much of the changes required by this Act are still being initiated and may take years to fully implement. Most dischargers still have valid permits issued in terms of the Water Act of 1956 (Act 54 of 1956), and these permits must be replaced by licenses issued in terms of the National Water Act of 1998 (Act 36 of 1998). An important conclusion from this study is that the legislation is not prescriptive in terms of specifying discharge license conditions, but instead allows the relevant authority, the Department of Water Affairs and Forestry to adjust the stringency of such licenses to suite the degree of impacts resulting from such discharges. Discharge licenses are therefore very site-specific and tailored to suite the type of discharge and impacts on the receiving water and other water users. In this way the requirements of all water users, including the aquatic ecosystem of the receiving water body, are taken into account, and protected. One suggested improvement to the SA legislation however, is to regulate industrial dischargers to sewer using national legislation. This is currently regulated by the by-laws of the relevant local authority, but is often insufficient to protect the sewage works and ensure the proper functioning of these works, which is largely dependant on the quality of raw sewage intake. Further research is required to determine the impact of industrial dischargers to sewer, and investigate how to regulate such discharges using national legislation. This study additionally assessed the implementation of SA legislation and the effectiveness of control over sewage dischargers. Enforcement of this legislation is not necessarily uniform, since much of the responsibility to enforce discharge permits and licenses lie with various officials within the Department of Water Affairs and Forestry. One way to ensure uniformity would be to require regular auditing by higher levels and management within this Department. Another important aspect of enforcement of these permits and licenses is that all permit and license holders, including Local Authorities, should be treated in the same way.
45

The Evolution of a Municipal Solid Waste Disposal System: A Design Case Study

Love, Osborne Raymond 07 1900 (has links)
A record of the design evaluation of a municipal solid waste disposal system has been made. The record was arranged chronologically on a process basis. The author had presented his analyses of the design influences. Emphasis has been put on the major influences. Observations and analyses of a more general nature, plus personal views of the case study method are also given. Recommendations for further study of this project are provided in a test proposal outline for the system. / Thesis / Master of Engineering (ME)
46

Profile of corporate disposal : evidence from the UK market

Assadi, Gholam Hossein January 1999 (has links)
Owners wishing to sell their business have a number of alternative exit routes. In a UK context, they may opt for a public sale of their shares either through the London International Stock Exchange, main market or on the AIM. Alternatively, they may choose a private sale route i.e. MBO or trade sale. This study aims to investigate the connection between the financial characteristics of firms and their choice of exit route. In particular company capital structure and valuation measures are used to discriminate between alternative exit routes and explain the rationale and factors for such segmentation in the market for corporate control. This research uses a discriminatory model to classify the preferred type of realisation route for a firm based on its financial characteristics. A classificatory accuracy better than that obtained by chance provides evidence of some segmentation of alternative disposal routes. A further aim is to consider the role of the large corporate finance advisory industry, which obtains large fees for their proficiency in disposal in the correct market. An attempt has therefore been made to see whether particular types of companies are suited to particular markets on the basis of their financial characteristics and whether this corresponds to actual outcome. We also investigate and evaluate the opportunity cost of misclassification both by the models and by the advisors. The results, in general, suggest that size and capital structure emerge as important discriminators. However, growth and working capital management were also found to contribute in discriminating between the suitability of particular companies for given exit routes. Our investigation demonstrates that discriminant (and logistic regression) models can assign cases to particular markets on the basis of financial attributes at above chance frequency and substantial valuation differences between the various markets are evident. Attention is also given to the opportunity costs involved in differences between indicated and chosen exit route. The results show that out-performing as well as under-performing misclassification errors occur and that the status of advisor seems to play a discussible role.
47

Performance and characteristics of biogranules in thermophilic UASB reactors

劉偉藻, Lau, Wai-cho, Ivan. January 1996 (has links)
published_or_final_version / Civil and Structural Engineering / Master / Master of Philosophy
48

Reduced domestic water use

Bohac, Charles E. January 1975 (has links)
Domestic waste water from toilets, showers, garbage grinding, and kitchens was characterized in terms of waste concentration and volume in order to formulate four representative synthetic domestic wastes. The synthetic waste formulations were used to simulate concentrated domestic wastes flowing from dwellings whose water use has been reduced by the use of water saving devices such as low flow toilets and showers. Biological treatment of wastes with Chemical Oxygen Demands (COD) of up to 1500 mg/1 using activated sludge was investigated with both bench scale batch and continuous processes. Specific items investigated as functions of waste concentration included substrate removal rates, oxygen uptake rates, aeration properties, sludge settling, sludge aeration time, and aeration tank turbulence. Substrate removal rates were not enhanced by increasing domestic waste concentrations although oxygen uptake rates did increase slightly due to possible differences in sludge yield. The minimum sludge aeration time was found to be between 12 and 16 hours per day. Increasing mixing intensity in the aeration tanks reduced sludge settling ability without significantly improving the substrate removal rate. Aeration properties of systems treating wastes at 1500 mg/1 COD were found to be inferior to those of systems treating wastes at 750 and 250 mg/1 COD. No significant differences were observed between systems treating 250 and 750 mg/I COD wastes. Results indicate that reducing the flow of water from domestic residences reduces treatment costs only so far as that afforded by the reduction in clarifier size and pumping costs.
49

Landfill as an anaerobic filter for the co-disposal of phenolic wastewaters

Watson-Craik, I. A. January 1987 (has links)
No description available.
50

An evaluation of enzyme activities in captor and activated sludge biomass

Richards, S. R. January 1983 (has links)
No description available.

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