The aim of this paper is to recommend a kinetic model related to UV disinfection of the secondary treated wastewater. Results revealed that application of the model of Chick-Watson in its original form is not representative of the kinetics of disinfection. Modification considering the speed change during the disinfection has not significantly improved the results. According to the parameter ε representing, the difference between the experimental and the calculated values using the model of Chick-Watson in its original form appeared feeble for all bacterial strains studied. Thus, we see therefore that the model of Collins-Selleck was most effective in considering the change in the kinetics of inactivation during the disinfection. Also, we found for the most strains of Pseudomonas aeruginosa tested that the model of Hom showed a great agreement to describe the kinetics of UV disinfection. Modeling the reactivation at the range of temperature of 7.5-50°C was presented. First-order saturation model does not fit the obtained data of photoreactivation; a modification of the model is recommended which coincides with the classical logistic equation.
Keywords: Secondary wastewater, disinfection, modeling, UV irradiation, kinetic, photoreactivation, pathogenic, UV254, UV transmittance, Chick-Watson model, Collins-Selleck, kinetic parameters, correlation, regression, inactivation.