Simulation model of a water treatment plant

Water treatment for large communities is an expensive venture involving substantial sums of capital outlay. Water treatment plant design attempts to create conditions favourable for physico-chemical processes of purification. However plant operators often realise, long after installation, that some of the unit processes require modifications to facilitate efficient operation. While these process modifications may require additional expenses, the most beneficial changes often result in substantial savings in operational costs. Therefore simulation study of model plants could be a useful tool in performance evaluation and in assessing the impact of any required modifications to existing full-scale treatment plants. This paper report the results of a simulation model study of the Durban Heights Water Treatment Plant (DHWTP). A laboratory model of a typical water treatment plant was designed, constructed and installed at the University of Durban-Westville. Using the model to treat raw water from the Durban heights treatment plant intake, the performances of flocculation, coagulation, sedimentation, filtration and disinfection processes were evaluated based on results from routine analysis of samples of raw, post-sedimentation, pre-chlorination, and treated water. The results obtained were compared with data from the Durban heights water treatment plant and the paper concludes with useful recommendations that could enhance the efficiency of the treatment plant.