GUIDELINES FOR THE SELECTION AND EFFECTIVE USE OF OZONE IN WATER TREATMENT

The use of ozone as a pre-oxidant for water treatment is gaining momentum in South Africa. A case study has indicated that there are five waterworks in South Africa, where ozone is used successfully as a pre-oxidant for the treatment of raw waters with high levels of iron and manganese, colour through presence of humic acids, taste and odour, chlorophyll ’A’. Because ozonation is energy intensive and also has the potential to form harmful disinfection by-products (DBP), the ozone option should be based on a systematic and rigorous approach. A user friendly, practical guide, that summarises the rationale for the inclusion of pre-oxidation in the water treatment train, selection of the appropriate oxidant for the application, and operational strategies for the cost-effective use of ozone in water treatment, has been compiled. The guideline also assists in the selection of hardware that includes oxygen feed source and preparation, ozone generation, contacting and destruction