An Efficient Contact Tank Design for Potable Water Treatment

Abstract

In this study, a second order accurate Large Eddy Simulation (LES) model is used to simulate three-dimensional turbulent flow and disinfectant transport in a contact tank. The hydraulic and mixing indexes of the tank are evaluated based on computational tracer studies. It is shown that the energy consumption rates of the contact tank can be reduced by the use of the proposed slot-baffle design instead of the conventional baffle system that is used in these facilities. The proposed slot-baffle design improves the hydraulic efficiency by 44%, mixing efficiency by 42% and reduces the energy required to drive the flow through the system by 43%. The outcome reported in this study shows that the energy consumption in water treatment plants can be significantly reduced when the novel baffle design is implemented on existing contact tanks without expensive infrastructure modifications.