Thesis submitted in compliance with the requirements for the Doctoral Degree in Technology: Biotechnology at the Durban Institute of Technology, 2003. / Globally, wastewaters emanating from edible oil manufacturers contain high organic (BOD & COD) and phosphate loads and known for creating shock-loading problems for the receiving wastewater treatment installations. Discharge of poor quality final effluents also negatively impact on and cause eutrophication of natural water sources such as rivers and dams. In South Africa, a large concentration ofthe edible industries are localized in the Pietermaritzburg region of Kwa-Zulu Natal and have been regularly associated with discharge of poor quality final effluent that did not subscribe to municipal regulation standards. Current treatment of choice for wastewater's in the edible oil industry have been limited primarily to dissolved air flotation combined with the use of chemical coagulants or physical separation of oil and grease via a gravity fat trap and subsequent pH correction. These physico-chemical methods have achieved limited success and the emulsified grease tends to clog sewer pipes and pumps producing poor quality effluents. Therefore, the aim of the current research was to develop suitable treatment technology focussing on adapting activated sludge process to remediate edible oil effluents and determine the microbial community of the process using novel molecular techniques. / D

Dissertation submitted in compliance with the requirements of the Master' s Degree in Technology: Biotechnology at the Durban Institute of Technology, 2004. / The objective of this study was to evaluate the characteristics and treatability of process wastewater from an edible oil refining industry, which discharge its effluent into a sewer system. The main objective was to assess a laboratory scale treatment process that would produce effluent having a regulatory acceptable phosphate concentration (below 20 mgIL) prior to discharge into municipal sewer system. A single stage laboratory-scale anaerobic-aerobic sequencing batch reactor (BPR-SBR) with a total volume adjustable up to 10L was designed for biological phosphorus removal. The BPR-SBR was run at 10 days sludge age, 8 hours hydraulic retention time and organic load of ~ 0.38 kg COD/kg MLSS.d for 158 days to evaluate its performance for bio-P removal efficiency. The BPR-SBR system showed a consistent P removal efficiency of up to 78.40 %, 80.15 % COD and 72.43 % FOG reduction. The laboratory scale study has demonstrated that the SBR technology is suitable for treating wastewater from edible oil producing industry. / M