According to the Department of Water Affairs (DWAF, 2004 p.15), South Africa’s water resources are scarce and extremely limited and much of this precious resource is utilised and consumed in our industries. Treatment and re-use of effluent generated is, in some cases, preferred over use of alternate water resources (Du Plessis, 2008 p.3). The volume of effluent generated in treatment processes like ultra-filtration (UF) and reverse osmosis (RO) units is determined by the feed water quality, with high water loss through effluent generation at poor feed water quality. Current UF and RO applications require an increased UF production capacity due to the use of UF filtrate for periodic backwashing of the UF membrane units. This results in loss of water and decreases overall recovery. The need therefore exists to increase the overall recovery of product water from the raw water stream by reducing the amount of effluent generated. This would be possible to achieve by using RO brine to backwash the UF unit. The study was conducted to provide a modelling tool, assisting management to optimise the use of RO brine as backwash water on the UF system at the Medupi power station. The secondary objective of this study was the development of a modelling tool that can be used for other projects, new or existing, as a measure and indication of the usability of RO brine as backwash water on UF systems. By successfully applying this newly developed model, the viability of utilising the RO brine as backwash water for the UF was investigated. This modification would lead to utilizing smaller UF units than previously envisioned, which in turn leads to reducing capital cost with 11.07% and operating expenditure with 9.98% at the Medupi power station. This also has a positive environmental impact by reducing the amount of raw water used monthly by 10.34% (108 000 m3/month). / MIng (Development and Management Engineering), North-West University, Potchefstroom Campus, 2014

According to the Department of Water Affairs (DWAF, 2004 p.15), South Africa’s water resources are scarce and extremely limited and much of this precious resource is utilised and consumed in our industries. Treatment and re-use of effluent generated is, in some cases, preferred over use of alternate water resources (Du Plessis, 2008 p.3). The volume of effluent generated in treatment processes like ultra-filtration (UF) and reverse osmosis (RO) units is determined by the feed water quality, with high water loss through effluent generation at poor feed water quality. Current UF and RO applications require an increased UF production capacity due to the use of UF filtrate for periodic backwashing of the UF membrane units. This results in loss of water and decreases overall recovery. The need therefore exists to increase the overall recovery of product water from the raw water stream by reducing the amount of effluent generated. This would be possible to achieve by using RO brine to backwash the UF unit. The study was conducted to provide a modelling tool, assisting management to optimise the use of RO brine as backwash water on the UF system at the Medupi power station. The secondary objective of this study was the development of a modelling tool that can be used for other projects, new or existing, as a measure and indication of the usability of RO brine as backwash water on UF systems. By successfully applying this newly developed model, the viability of utilising the RO brine as backwash water for the UF was investigated. This modification would lead to utilizing smaller UF units than previously envisioned, which in turn leads to reducing capital cost with 11.07% and operating expenditure with 9.98% at the Medupi power station. This also has a positive environmental impact by reducing the amount of raw water used monthly by 10.34% (108 000 m3/month). / MIng (Development and Management Engineering), North-West University, Potchefstroom Campus, 2014

Sustainable development is described by the World Commission on Environment and Development as ―development that meets the needs of present without compromising the ability of future generations to meet their own needs‖. Sustainability assessments are an integrative process and framework for effective integration of social, economic and ecological considerations in significant decision-making processes. Sustainability is incorporated into South African legislation such as the Constitution of the Republic of South Africa (1996), the National Environmental Management Act (Act 107 of 1998), as well as Environmental Impact Assessment (EIA) Regulations. Despite the existence of such legislation, the challenge lies in the effective implementation of the EIA process, which has been identified as a useful tool in striving towards achieving sustainable development. This research uses Gibson‘s eight sustainability principles and Gaudreau and Gibson‘s sub-criteria to develop a case specific set of sustainability criteria for coal fired power stations in South Africa. The energy generation sector is a major source of social and environmental impacts. Coal power stations contribute to environmental degradation such as reduced air, water and land quality. This industrial process impacts on the environment and therefore needs to strive towards sustainable development by considering these criteria during the EIA process. The set of case specific sustainability criteria for power stations was then used to evaluate the EIA developed for Medupi Power Station in South Africa in order to assess, the extent to which sustainability was considered in the EIA process. The key finding is that sustainability is incorporated into South African legislation hence no change in legislation is required. Despite the existence of legislation, the challenge lies in the fact that is it not always effectively implemented. The EIA process is seen as a tool that can effectively deliver sustainability outcomes. However this process is not effectively utilised. In order for the EIA to consider sustainability the focus needs to be on the following criteria: Intragenerational Equity; Precaution and Adaptation for Resilience; as well as Immediate and Long term Integration, as these were recognised as weaknesses after the evaluation process. The recommendation is also to develop a set of case specific sustainability criteria for other large industries that have significant environmental impacts. / MSc (Environmental Management), North-West University, Potchefstroom Campus, 2015

Sustainable development is described by the World Commission on Environment and Development as ―development that meets the needs of present without compromising the ability of future generations to meet their own needs‖. Sustainability assessments are an integrative process and framework for effective integration of social, economic and ecological considerations in significant decision-making processes. Sustainability is incorporated into South African legislation such as the Constitution of the Republic of South Africa (1996), the National Environmental Management Act (Act 107 of 1998), as well as Environmental Impact Assessment (EIA) Regulations. Despite the existence of such legislation, the challenge lies in the effective implementation of the EIA process, which has been identified as a useful tool in striving towards achieving sustainable development. This research uses Gibson‘s eight sustainability principles and Gaudreau and Gibson‘s sub-criteria to develop a case specific set of sustainability criteria for coal fired power stations in South Africa. The energy generation sector is a major source of social and environmental impacts. Coal power stations contribute to environmental degradation such as reduced air, water and land quality. This industrial process impacts on the environment and therefore needs to strive towards sustainable development by considering these criteria during the EIA process. The set of case specific sustainability criteria for power stations was then used to evaluate the EIA developed for Medupi Power Station in South Africa in order to assess, the extent to which sustainability was considered in the EIA process. The key finding is that sustainability is incorporated into South African legislation hence no change in legislation is required. Despite the existence of legislation, the challenge lies in the fact that is it not always effectively implemented. The EIA process is seen as a tool that can effectively deliver sustainability outcomes. However this process is not effectively utilised. In order for the EIA to consider sustainability the focus needs to be on the following criteria: Intragenerational Equity; Precaution and Adaptation for Resilience; as well as Immediate and Long term Integration, as these were recognised as weaknesses after the evaluation process. The recommendation is also to develop a set of case specific sustainability criteria for other large industries that have significant environmental impacts. / MSc (Environmental Management), North-West University, Potchefstroom Campus, 2015