Modelling of flow, transport and disinfection kinetics in contact tanks Available to Purchase

Results of a computational fluid dynamics (CFD) study of flow, transport processes and pathogen inactivation in contact tanks are presented. The three-dimensional numerical simulations are first validated using data from a previously completed laboratory experiment and velocity and conservative tracer transport data are available for comparison. The good agreement between CFD and experimental data confirms that the model reproduces accurately hydrodynamics and tracer transport processes. The analysis of the results reveals that the flow in the tank features extensive three-dimensionality, which is attributed to the current inlet configuration. Pathogen inactivation simulations show that complex flow in the tank affects the disinfection performance negatively. The potential for tank optimisation is examined by way of additional simulations featuring varying inlet designs, where it is shown that optimisation of inlet condition enhances the performance of the tank in terms of pathogen inactivation level for the same disinfectant dosage or the possibility of disinfectant dosage reduction towards reduced disinfection by-product production.