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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.
1

'n Evaluering van die drupfiltrerings- en die geaktiveerde slykproses van die Johannesburg-Noord rioolwerke deur middel van die biologiese groeipotensiaaltegniek

Brown, Leslie Robert 01 April 2014 (has links)
M.Sc. (Botany) / A comparison was made between the effectiveness of the biological filtering and activated sludge processes at the Johannesburg North Sewerage Works by making use of, inter alia, the physical-chemical and biological research methods. In addition to the standard physical and chemical analytical techniques, the biological growth potential technique, the lC method of determining primary productivity and biomass determination by way of the chlorophyll a method, were also used. The most important findings were: 1. that the activated sludge process purifies the water more effectively than the biological filtering process; 2. that no seasonal fluctuations affecting the effectiveness of the purifying systems were found, and 3. that the biological growth potential of the effluent in the Jukskei River was such that it could still cause algal growth. The primary recommendation is that tertiary purifying techniques will have to be employed in order to reduce The high phosphorous levels still prevailing in the effluent to comply with the requirements of the Water Act of 1984.
2

Investigation to determine the effectiveness of a commercially available pit latrine additive and the development and evaluation of a testing protocol.

Bindoff, Anna Maria. January 2008 (has links)
The provision of sanitation services during the apartheid era in South Africa was minimal or non-existent in the previous "black" areas and for farm workers. Whatever service that was provided was often in a bad state of disrepair. One of the priorities established in the post 1994 elections was to improve the quality of lives for the previously marginalised and neglected communities. This was done through the development and implementation of a policy for reducing the sanitation backlog, and for the provision of a basic level of sanitation. The principles encompassed in the policies developed for poverty alleviation and sustainable development had many points in common with the United Nations Millennium Development Goals and targets declared in 2000. The provision of Ventilated Improved Pit (VIP) latrines by municipalities satisfies the minimum requirements for basic sanitation. This provision together with the awareness programs are seen to offer communities an improved environment and hence living conditions. Problems arise however, due to the rapid filling, blockages and even the overflow of these pits. The emptying of these pits is also hazardous due to the nature of the waste. One of the solutions proposed by entrepreneurs was to supply additives that would enhance the degradation processes in the pit thereby increasing the Iifespan of these pits as well as offering other benefits; reduced odours, and flies. The aim of this research work was to test the claim of enhanced degradation by determining the effectiveness of an additive, M, which was deemed to be representative of a group of additive; made up of aerobic microbes and enzymes. The objective was to supply information to the municipality planners and decision makers in municipalities to assist them in their planning for improved management of pits. Waste was removed from suitable VIPs and used as samples for laboratory scale experiments. Reactor vessels were designed to simulate pit conditions. The additive was tested on the waste as recommended by the supplier and compared in activity against waste tested as references. The reference tests had (i) no addition of additive or water, as well as (ii) varying the volume of water added and (iii) varying the frequency of water addition, no additive added. Measurements were made of the following variables: • Total mass • Chemical oxygen demand. • Total solids • Volatile solids. • Ash. The results of the experimental vessels were analysed and compared with the reference vessels to reveal any differences. The results obtained did not present enough precision and reliability to make any conclusive decision as to whether the additive is effective or not. Recommendations made were to improve the test methodology using the same additive, to obtain results that would make a conclusive decision possible. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2008.
3

Investigation and development of methods for optimal control of the activated sludge process

Kujane, Koketso Portia January 2009 (has links)
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009. / This project was started as a result of strict environmental and health regulations together with a demand for cost effective operation of wastewater treatment plants (WNTPs). The main aim of this project is how to keep effluent concentration below a prescribed limit at the lowest possible cost Due to large fluctuations in the quality and quantity of the influent concentrations, traditional control methods are not adequate to achieve this aim The major drawback with these methods is that the disturbances affect the process before the controller has time to correct the error (Olsson and Newell, 1999: 454). This problem IS addressed through the use of modern control systems Modern control systems are model based predictive algorithms arranged as feed-forward controllers (Olsson and Newell, 1999: 454) Normally a controller is equipped with a constant set point; the goal In this project IS to calculate an optimal DO trajectory that may be sampled to provide a varying optimal set-point for the Activated Sludge Process. In this project an optimal control problem is formulated usmq 00 concentration as a control variable This requires a model of the process to be controlled, a mathematical expressions of the limitations on the process input and output variables and finally the objective functional which consists of the objectives of the control. The structures of the Benchmark plant (developed within the COST 682 working group) and the Athlone WWTPs are used to implement this optimal control strategy in MATLAB, The plant's full models are developed based on the mass balance principle incorporating the activated sludge biological models. ASM1, ASM2 ASM2d and ASM3 (developed by the IWA. working groups) To be able to develop a method that may later on be used ~or online control. the full models are reduced based on the technique in Lukasse (1996) To ensure that the reduced models keep the same prediction capabilities as the full models paran-eters of the reduced models are calculated based on the Least Squares principle. The formulated optimal control problem IS solved based on the decomposition-coordination method that involves time decomposition 111 a two layer structure, MATLAB software is developed to solve the problems for parameter estimation full and reduced model simulation and optimal control calculation for the considered different cases of plant structures and biological models, The obtained optimal DO trajectories produced the effluent state trajectories within prescribed requirements. These DO trajectories may be implemented in different SCADA systems to be tracked as set points or desired trajectories by different types of controllers.
4

A Review of policies for sustainable solid waste management service in Buffalo City Metropolitan Municipality

Qhayi-Shweni, Nokuzola January 2014 (has links)
Waste is not only harmful to the environment alone but it is also a threat to human health and as such its proper management becomes critical. This study which adopted a qualitative approach focused on the review of policies for sustainable solid waste management service in Buffalo City Metropolitan Municipality in an effort to seek what the municipality’s Solid Waste Department should consider in ensuring that all the communities live in a litter free, clean and healthy environment, and ensure that such a service is received by all communities within its jurisdiction. The most sustainable solid waste management strategy would be to adopt the solid waste hierarchy of promoting waste minimisation, re-use, recycling, waste treatment and disposal as the last resort.
5

The use of treated effluent for agricultural irrigation in the Bottelary River area: Effluent quality, farmers perception and potential extent.

Rui, Li January 2005 (has links)
The Bottelary River area is located in a Mediterranean climate region, where the agricultural sector plays an important role. During the dry summer season, there is not enough precipitation to meet the agricultural irrigation requirements. Some farmers extract river water which is practically the final treated effluent from the Scottsdene Wastewater Treatment Works to irrigate crops. This research investigated the use of treated effluent for agricultural irrigation in this area, particularly focused on the effluent quality, farmers perception, and the potential extent.
6

The use of treated effluent for agricultural irrigation in the Bottelary River area: Effluent quality, farmers perception and potential extent.

Rui, Li January 2005 (has links)
The Bottelary River area is located in a Mediterranean climate region, where the agricultural sector plays an important role. During the dry summer season, there is not enough precipitation to meet the agricultural irrigation requirements. Some farmers extract river water which is practically the final treated effluent from the Scottsdene Wastewater Treatment Works to irrigate crops. This research investigated the use of treated effluent for agricultural irrigation in this area, particularly focused on the effluent quality, farmers perception, and the potential extent.
7

The management of sanitation in a selected area in the Western Cape, South Africa

Lemone, Julian January 2019 (has links)
Thesis (MTech (Public Management))--Cape Peninsula University of Technology, 2019. / The research provides a broad overview of the problem statement, research objectives, demarcation of the research, research methodology, and significance of the research, a brief literature review and the ethics statement. Theoretical background through a literature review of the selected topic, as well as of the legal frameworks that guide the provisioning of sanitation. The researcher consulted literature that describes the provisioning of sanitation by the City of Cape Town, and the challenges it faces in this regard. The researcher also discussed the legislation that guides sanitation, and five broad themes relating to sanitation, around which the research questions were formulated. The researcher discovered that City of Cape Town employees face a number of challenges that make their job difficult, especially in providing water and sanitation to the communities in Site C in Khayelitsha. The researcher concludes the study and makes recommendations regarding the provision of proper sanitation by the City of Cape Town. These recommendations are based on the study's questionnaire results
8

Community involvement in the provision of basic sanitation services to informal settlements

Cousins, Deborah January 2004 (has links)
Thesis (MTech (Public Management))--Peninsula Technikon, Cape Town, 2004 / In South Africa, an estimated 15 million people - 38% of our population - do not have adequate sanitation. Every citizen has a constitutional right of access to basic services, which local government has the responsibility to provide. In reality such provision to people living in poverty is a daunting development challenge, exacerbated by growing unemployment and the spread of unplanned informal settlements. On the other hand, increased government investment in accelerating provision is a significant opportunity to link sanitation delivery to local economic development, as suggested in the recently revised Water Services Strategy document (DWAF, 2003). There is evidence that these two aspects of national policy can be brought together fruitfully. Community involvement, described as "a commitment to building on people's energy and creativity" (WSSCC, 2001) is consistently advocated by international, national and local government (DPLG, 2001) as essential to sanitation provision. There is broad agreement that a community-based approach is the cornerstone of sustainable service provision. This research focused on the context of urban poverty in informal settlements, taking community responses to sanitation delivery by local authorities into account. Prevailing approaches have had limited success in preventing health hazards, which relies on community-level actions to deal with poor use, inadequate maintenance and dysfunction of such sanitation services as are provided. Implicit in the principles underlying the involvement of communities are substantial community-based roles and functions that the research seeks to make explicit. Diverse local level capacities emerge as quite distinct opportunities for residents to become more actively involved in improving and sustaining their sanitation services.
9

Effect of social norms and attitudes towards domestic waste in a selected formal settlement in the Western Cape, South Africa

Tahulela, Aifani Confidence January 2017 (has links)
Thesis (MTech (Public Management))--Cape Peninsula University of Technology, 2017. / The communities of Khayelitsha face problems with regard to managing waste. Increase on the generation of solid waste in the households by the members of the community; far exceed the townships’ ability and capability for safe disposal. Littering in the township is also a persistent problem, despite various clean–up and anti-litter promotional campaigns and programs introduced by local government, private organizations and other community interest groups. The persistent problem of litter and mismanagement of solid waste in the household should be addressed. The rationale and assumption underpinning this study was that waste management problems are related to social norms and attitude of the people of Khayelitsha. To investigate this phenomenon, the study adopted a qualitative paradigm. 300 heads of household residing in Khayelitsha for more than 5 years were surveyed, and door to door interview questions were conducted in 2016 June. Data from the questionnaire were analysed using Thematic and coding analysis. NVivo software was used to generate frequency tables. The responses to most interview questions were consistent for all categories of respondents and did not vary according to respondents’ background, such as gender, location household size or education. The study showed that social norms and attitudes towards waste minimisation in Khayelitsha are related to the entire waste management operation, and householders in Khayelitsha think similarly. To improve waste management in Khayelitsha the following are recommended: • Government and business need to consider incentives to minimise waste; • Government needs to improve waste management service facilities and build recycling centre which are accessible to the community; and • Government and non-governmental organizations and community members should consider awareness, education and training programs on waste wise management.
10

Evaluating the impact of asset management in the water industry : a case study of East Rand Water Care Company (ERWAT)

Mhlongo, Thabani 04 1900 (has links)
Thesis (MPA)--Stellenbosch University, 2014. / The asset management process and strategy has been adopted and implemented within the public sector. Although the National Treasury developed the Capital Asset Management Guidelines to assist with the development and implementation of the asset management system the guidelines have received very little attention over the years. The Auditor General’s findings indicate a lack of proper implementation of the asset management process. The study provides a clear indication of the implementation of the asset management process by most government entities, local government municipalities and the public sector. The outcome is that while most entities have made progress with regards to the implementation, much remains to be done. Most entities implement the asset management process selectively. This does not yield positive and sustainable results and they end up abandoning the whole asset management system. The report provides the process of successful development and implementation of asset management, it also indicate that if there are element that are missed or not properly done the process will not yield constant results or performance and the impact on the organization performance will not be positive. The management of the organization must ensure that asset management is aligned with strategic objectives of the organization and performance measurement must be directly linked with asset management, performance measurement should be used to determine progress and implementation. Service level agreements must be established between all relevant departments including the finance department and there must be agreement on the objectives between all stakeholders. The key to proper implementation is the alignment of the asset management process with the strategic objectives of the organization.

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