Wastewater Technologies in South Africa: Research and Application

Abstract

South Africa's water economy has necessitated concerted research on aspects contributing to water and wastewater management and water reuse. This paper deals briefly with highlights of research and application in these areas. Development of advanced wastewater treatment technology has led to its application in the reclamation of potable water in Windhoek, and of process water for the pulp and paper industry. Reverse osmosis shows great promise as an alternative water reclamation process to abate the build-up of inorganic salts within the cycle of use, reclamation and reuse. Ion exchange and ultrafiltration have been successfully applied in the recycling of water and chemicals in the textile industry. Studies on biological nutrient removal have resulted in the development of the novel Bardenpho process and its modification, the Phoredox process. Particular attention has been devoted to water quality control and to health aspects. Of special significance has been the postulation of pollution indices based on chromatograms of a series of potentially harmful organic pollutants and the finding that routine, expensive enteric virus monitoring can be replaced with simpler, equivalent bacterial tests. The Ames test and a mammalian cell bioassay have been adopted for the detection of potential carcinogens in water. Biological monitoring systems using fish and another assay using a protozoan have been developed, primarily for quality control of industrial effluents. However, continual development and application of new knowledge is a necessity for further growth.