Environmental and Mining Engineering,

UV disinfection is now widely used for the treatment of water for consumption and wastewater in many countries. It offers advantages over other techniques in specific circumstances. Analysis of these systems has been carried out using a three-dimensional Computational Fluid Dynamics (CFD) procedure. This allows for efficient testing of prototypes. Sensitivity tests are shown for grid size, discretisation and turbulence model. Four different configurations of the apparatus are evaluated in terms of maximum dosage, flow patterns, particle tracks and transient dosage. This leads to conclusions about the most efficient design and shows that significant improvements can be achieved with minor changes to the design. Further conclusions are drawn about the CFD procedure itself. This work opens up the possibility of an internet-based design tool for small- and medium-sized enterprises. Key words | water treatment, computational fluid dynamics, ultraviolet treatmen