M. Tech. Water Care / Aims of the study was to recommend probable management procedures that could be used in small water treatment plants in order to produce safe drinking water.

Wastewater treatment facilities have been identified as potential source of surface water pollution worldwide. In this study, the physicochemical qualities and heavy metal (including Zinc, Cadmium, Iron, Lead and Copper) concentrations in the final effluents, as well as the reduction efficiencies of three municipal wastewater plants in the Eastern Cape, South Africa were evaluated from September 2015 to February 2016 using standard methods. Wastewater effluent and sludge samples were collected from the selected plants on monthly basis over a period of six months from September 2015 to February 2016. Standard analytical method (Atomic absorption spectroscopy [AAS]) was used to assess the concentration levels of heavy metals. The physicochemical parameters assessed include pH, Temperature, Total Dissolved Solid, Turbidity, Biochemical Oxygen Demand, Chemical Oxygen Demand, Alkalinity, Dissolved Oxygen, Free chlorine, Chloride, Sulphate, Phosphate, Ammonium and Electrical Conductivity. The results of the evaluation showed that temperature ranges from 19 to 36 °C, Electrical Conductivity from 60-1095 mS/m, Alkalinity from 2.6-20.9 mg/L, Nitrate from 0.24-26.5 mg/L, Nitrite from 0.01-90 mg/L, Phosphate from 0.02-5.12 mg/L, Ammonium from 0.06-112 mg/L, Sulphate from 3-72 mg/L, Chloride from 3.25-224 mg/L, Chemical Oxygen Demand from 17-394 mg/L and Turbidity from 1.96-715 NTU. Free chlorine concentrations and dissolved oxygen were within the recommended limits for most part of the sampling period and ranged between 0.17-0.48 mg/L and 0.19-21.9 mg/L respectively. The pH, Phosphate, Sulphate and Free chlorine were within acceptable limits while Electrical Conductivity, Temperature, Total Dissolved Solid, Turbidity, Chemical Oxygen Demand, Chloride, Ammonium, Nitrate and Nitrite were not within specified limits. The reduction efficiencies observed generally ranged between 43.9 and 100 percent at all sampling points while zinc and lead were not detected throughout the sampling period. Cadmium showed low reduction rate ranging from 0 to 11.7 percent, while the rate of Copper reduction ranged from 0 to25 percent in January and February 2016. Zinc, lead and cadmium were generally not detected in the sludge samples except in January and February which could be due to the prevailing atmospheric conditions during the sampling period. Cu and Fe were detected through the sampling months of the study. We conclude that these municipal sewage plants are sources of pollution to their receiving watersheds and threats to public and environmental health.

M.Ing. / A number of distinctly different local and international media specifications are currently being used in South Africa. Along with some opposing requirements, these specifications all specify different testing procedures to be used in the evaluation of filter media. Furthermore the already confusing situation is being complicated by a lack of knowledge as to the general properties of South African filter media ...

A significant trend in the modern day industrial biotechnology is the utilization and application of renewable resources, and ecofriendly approach to industrial processes and waste management. As a consequence thereof, the biotechnology of holocellulases: cellulase and xylanase and, enzymatic hydrolysis of renewable and abundant lignocellulosic biomass to energy and value added products are rapidly increasing; hence, cost effective enzyme system is imperative. In that context, exploration of microbiota for strains and enzymes with novel industrial properties is vital for efficient and commercially viable enzyme biotechnology. Consequent on the complex characteristics of high salinity, variable pressure, temperature and nutritional conditions, bacterial strains from the marine environment are equipped with enzyme machinery of industrial importance for adaptation and survival. In this study, bacterial strains were isolated form Nahoon beach and optimized for holocellulase production. Three isolates selected for lignocellulolytic potential were identified by 16S ribosomal deoxyribonucleic acid (rDNA) sequence analysis. Isolate FS1k had 98 percent similarity with Streptomyces albidoflavus strain AIH12, was designated as Streptomyces albidoflavus strain SAMRC-UFH5 and deposited in the GenBank with accession number KU171373. Similarly, isolates CS14b and CS22d with respective percentage similarity of 98 and 99 (percent) with Bacillus cereus strains and Streptomyces sp. strain WMMB251 were named Bacillus cereus strain SAMRC-UFH9 and Streptomyces sp. strain SAMRC-UFH6; and were deposited in the GenBank with accession number KX524510 and KU171374 respectively. Optimal pH, temperature and agitation speed for cellulase production by S. albidoflavus strain SAMRC-UFH5, and B. cereus strain SAMRC-UFH9 were 6 and 7; 40 and 30 (°C); and 100 and 150 (rpm) respectively; while xylanase production was optimal at pH, temperature and agitation speed of 8 and 7; 40 and 30 (°C); and 150 and 50 (rpm) respectively. Maximum cellulase activity of 0.26 and 0.061(U/mL) by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 were attained at 60 h respectively, while maximal xylanase activity of 18.54 and 16.6 (U/mL) was produced by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 at 48 h and 60 h respectively. Furthermore, xylanase production by S. albidoflavus strain SAMRC-UFH5 and B. cereus strain SAMRC-UFH9 was maximally induced by wheat straw and xylan respectively, while cellulase production was best induced by mannose and carboxymethyl cellulose respectively. On the other hand, cellulase and xylanase production by Streptomyces sp. strain SAMRC-UFH6 was optimal at pH, temperature and agitation speed of 7 and 8, 40 °C and 100 rpm, respectively. Highest production of cellulase and xylanase was attained at 84 and 60 h with respective activity of 0.065 and 6.34 (U/mL). In addition, cellulase and xylanase production by the strain was best induced by beechwood xylan. Moreover, xylanase produced by Streptomyces sp. strain SAMRC-UFH6 at optimal conditions was characterized by optimal pH and temperature of 8 and 80-90 °C respectively; retaining over 70 percent activity at pH 5-10 after 1 h and 60 percent of initial activity at 90 °C after 90 min of incubation. In all, optimization improved cellulase and xylanase production yields, being 40 and 95.5, 10.89 and 72.17, and 10 and 115- fold increase by S. albidoflavus strain SAMRC-UFH5, B. cereus strain SAMRC-UFH9 and Streptomyces sp. SAMRC-UFH6 respectively. The results of this study suggest that the marine bacterial strains are resource for holocellulase with industrial applications.

Thesis (MTech (Civil Engineering))--Peninsula Technikon, 2004. / When considering water treatment in small rural and peri-urban communities, sustainability is one of the most important factors to be considered. Sustainability needs to be considered from financial, technological and socio-political perspectives. The major problems with sustainability of conventional small water treatment systems are the difficulty of controlling chemical treatment processes, especially when the raw water quality changes, and the production of substandard quality water. Another very important problem is lack of community involvement, especially over the longer term. The acceptance of new technologies by the community is of crucial importance in ensuring successful water supply projects. The anticipation of more stringent drinking water quality regulations and decrease in adequate water sources have brought membrane separation processes such as microfiltration and ultrafiltration on the advantage for potable water supply to rural and peri-urban areas. Membrane processes have the advantage of production of superior quality water and addition of fewer chemicals in the treatment process. The pUIpose of this study was to further investigate the potential of ultrafiltration capillary membranes as a one-step membrane water treatment system for potable water supply to developing communities. To successfully transfer a technology to a particular community, the technology must be suitable and acceptable and a social study was therefore also done to understand the social acceptance factors that govern the acceptance of these new technologies.

A total of 34 sewage sludge samples were collected from South African provinces: KwaZulu- Natal, Gauteng, North West and Western Cape province. The samples were analysed for mineral ions and polynuclear aromatic hydrocarbons (PAH). The methods used for sample preparation were US-EPA 3050B and 3540C for mineral ions and PAHs respectively. The moisture content was also analysed. A minimum of 4.5 % and maximum of 99.5 % moisture were detected in the samples. The sludge that had stayed longer in their sampling points had low moisture contents than those that were sampled immediately after production. A total of 22-minaral ions were detected in the samples. When these were quantified an abundance trend that was found to be most common was: P>Ca>Fe>Al>Mg>K>Zn>Na>Mn>Cu>Ba>Cr>Pb>Si>Se>Sr>B>Ni>Mo>Co>Cd>Be. Phosphorous was the most abundant mineral ion in most of the samples apart from calcium, which was found to be abundant in a few cases. Comparing these results to the South African guideline limits, it emerges that most of the sewage works are compliant with the guidelines. The mineral ion that was found to be above the set limit in most occasions was selenium. The current South African guidelines were found to compare favourably to those of other countries. In the study 16 PAHs were also analysed, based on frequency of occurrence these were found to be: benzo(b)fluorathene ~ benzo(k fIuoranthene> phenanthrene> acenaphthylene> fluorine> naphthalene> benzo(a)anthracene> chrysene> acenaphthene> benzo(a)pyrene> fluoranthene> anthracene ~ pyrene> benzo(g,h,i)perylene> indeno(l ,2,3-cd)pyrene> dibenzo(a,h)anthracene Dibenzo(a,h)pyrene was below the detection limit in all the samples analysed while benzo(b)fluoranthene and benzo(k)fluoranthene were the most abundant compounds. All the samples analysed had concentration of benzo(a)pyrene below the South African limit of 2.53 mg kg"1. Comparing these guidelines with other international countries, South Africa specifies a single compound for monitoring while in other countries more than one compound is monitored. Thus South African guidelines need to be put in line with those of major EU countries such as Germany and Denmark with respect to PAH limits. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

A comprehensive literature survey looking at different aspects of organic contaminants in sewage sludge is incorporated in the thesis. It is clear from the data available that plants do not take up most of the organic pollutants. However, a risk of contamination of the food chain exists when sludge is spread directly onto crops that are to be consumed raw or semi-cooked. The major source of human exposure to sludge-borne organic pollutants is through the consumption of animal products such as meat and milk through the bioaccumulation of compounds such as polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs), polychlorinated biphenyls (PCBs) or polynuclear aromatic hydrocarbons (PAHs). This is due to the ingestion of soil and sludge by livestock due to the spreading of sludge on the land used for grazing. Currently little is known about the plant uptake of phthalates and nonylphenols, which are present in relatively high levels in sludge. Included in the literature survey is a list of the most common methods normally used for extraction of organic compounds and the possible methods of analysis. What is noted is that there is no universally accepted and validated analytical method for analysing most of the organic compounds. In addition, data concerning levels of organic pollutants is scarce worldwide. The methods selected for this project were EPA Methods 35IOC (Liquid-liquid extraction) and 3540C (Soxhlet extraction) for the aqueous and solid sewage sludge respectively. These two methods were chosen because they are simple, inexpensive and effective. The chosen purification method was the sulfur clean-up process (EPA Method 3660B). This is because sulfur precipitates were observed in most of the concentrated extracts, especially from the solid samples. A total of 109 samples from 78 sewage works were extracted, using Soxhlet extraction for solids and liquid-liquid extraction for liquid samples. All the extracts were analysed using GC-MS. The identification of the organic compounds was made possible by the use of GC-MS Wiley library. A total of 712 organic compounds were identified in the South African sewage sludge. These included Phenols, Pesticides, PAHs, Phthalates, PCBs, Furans, Amines, Aldehydes, Esters, Acids, Chlorinated Hydrocarbons, Alcohols, Hydrocarbons and Others (all sorts of organic compounds that did not belong to the named categories). The extraction efficiency and reproducibility using a "clean" sludge matrix was carried out. The results showed that the method chosen for extraction i.e. Soxhlet method had an efficiency of over 80% and the results were reproducible. A total of 14 samples were selected for the quantification of p-cresol, nonylphenol and pesticides listed in the current legislation. The results showed negative results for pesticides, confirming that the pesticides listed in the legislation are not the compounds that need to be regulated as far as organic pollutants are concerned. The reasons for this are most likely due to the fact that most of the pesticides listed are banned or their use is severely restricted. The results for the quantification of p-cresol and nonylphenol, when comparing the liquid and the solid extracts of the liquid sludge, show that 99% of p-cresol is concentrated in the liquid phase. The opposite is true when looking at nonylphenol where 90% of it is trapped in the solid matrix leaving 10% in the liquid phase. It is also noted that liquid sludge contains high concentrations of both p-cresol and nonylphenol when compared to the solid sludge. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. August, 2017 / The foremost aim of potable water treatment is to produce water that does not pose a health risk when consumed and/or otherwise used. Nevertheless, research has established that the quality of treated water deteriorates during distribution. The nature and extent of this deterioration varies from system to system and from time to time. The aim of this research study was to monitor the parameters that are known to significantly affect biostability and biofilm formation potential in drinking water distribution systems. Biweekly water samples were collected from thirteen sites, across a section of Johannesburg Water’s network, between September 2015 and August 2016. All samples were assayed for a suite of fifteen water quality parameters using standard methods. Heightened temperature, dearth of chlorine residuals, availability of biodegradable dissolved organic carbon (BDOC), and advanced water age all engendered the loss of biostability (instability). Biostability controlling parameters varied seasonally and spatially. Samples collected during spring and summer, in general, were most likely to be characterized by instability than samples collected during winter and autumn. Samples collected from sites RW80, RW81, RW82, RW83, RW104 and RW253 were more prone to instability compared to samples from other sites. From the results, it is clear that chlorine residuals ought to be kept above 0.2 mg/l, and, BDOC below 0.3mg/l to prevent the loss of heterotrophic stability in distributed water. BDOC concentrations can be decreased by, flushing the pipes, cleaning reservoirs regularly and by further treating feed water before distributing. Booster disinfection can be relied upon to ensure that chlorine residuals are maintained throughout the network. Apart from potential health risks, biological instability and biofilm growth can result in non-compliance with regulations. / MT2018

M. Tech. Water care / Free-living amoebae are important predators that feed on bacteria, fungi and algae by phagocytosis. However, a number of bacteria have become resistant to, and are able to survive, grow and exit Free-living amoebae. Free-living amoebae are ubiquitous organisms that have been isolated from various man-made and environmental water systems. Some of these free-living amoebae host amoeba-resistant bacteria such as Legionella spp. Vibrio cholerae and Mycobacterium species which are regarded as human pathogens. The objective of this study was to establish amoebal enrichment and co-culture techniques in order to isolate and identify amoebae and amoeba-resistant bacteria from seeded and environmental water samples. The aim of the study was to introduce and establish amoebal co-culture and amoebal enrichment techniques in South Africa, to provides South African laboratories with baseline information on the efficiency of culture-based methods as well as analytical requirements like incubation temperature, media preparation and storage conditions for amoebal enrichment and co-culture techniques for the detection and isolation of amoebae and amoeba-resistant bacteria from environmental water systems.

The application of high rate algal ponds (HRAP) in the treatment of brewery effluent that met the South African Department of Water Affairs and Forestry's (DWAF) general limits for discharge into a natural water resource of 1998 were tested during a lO-month baseline phase, followed by an 11-month optimization phase. The objective of the baseline phase was to monitor the seasonal performance of HRAPs. The hydraulic retention time (HRT) fluctuated between 11.16 d and 12.00 d in HRAPs. The chemical oxygen demand (COD) increased from 130.12 ± 6.94 mg/L (post-AD), to 171.21 ± 7.99 mg/L (post-HRAP) . The presence of algal cells and evaporation contributed towards an increase in post-HRAP COD. The ammonia (NH₄-N) concentration decreased from 46.59 ± 2.47 mg/L (post-AD), to 1.08 ± 0.12 mg/L (post-HRAP). The nitrite (NO₂- N) concentration remained below 1.00 mg/L in post-pilot plant AD, post-PFP and post-HRAP effluent. The phosphate (PO₄-P) concentration decreased from 29.81 ± 1.39 mg/L (post-AD) to 17.30 ± 1.16 mg/L PO₄-P. The objective of the optimization phase was to manipulate the HRT to achieve the maximum treatment rate that met the DWAF general limits for discharge into a natural water resource of 1998. Nitrogen (as NH₄-N, NO₃-N, NO₂-N) removal efficiency was used as an indicator of nutrient removal success. HRT was influenced by season. The optimal HRT for autumn was 4.30 d at a temperature of 20.53ºC in HRAP A2 (heated) and 18.96ºC in HRAP B2 (ambient). The optimal HRT for summer was 2.74 d at 29.90ºC in HRAP A2 (heated) and 26.36ºC in HRAP B2 (ambient). The COD decreased from 152.33 ± 4.85 mg/L (post-AD) to 95 .00 ± 3.75 mg/L (post-HRAP A2), and to 100.82 ± 5.93 mg/L (post-HRAP B2). The incoming NH₄-N concentration decreased from 42.53 ± 1.38 mg/ L (post-AD), to 1.70 ± 0.81 mg/ L (post-HRAP) . The nitrate (NO₃-N) concentration post-HRAP was 12 - 14 mg/L. The main methods for NH₄-N removal were probably NH₄-N volatilization through algal uptake. HRAPs were able to lower nitrogen and phosphorous concentrations to within the DWAF limits under normal operating conditions. It is recommended that HRAP treated brewery wastewater be used for irrigation after salt removal, or alternatively, for groundwater recharge . Regulatory exemptions would be required for higher than permitted COD and EC concentrations to enable these actions.