Predicting disinfection performance in continuous flow systems from batch disinfection kinetics

Abstract

Disinfection processes have often been characterized by the “CT” concept i.e., the product of disinfectant residual and contact time (perhaps as a function of pH, temperature, and other water quality variations) produces a given level of disinfection. The objective of this work was to develop and validate the use of reaction kinetic models for disinfection process design. Using bench scale (batch) kinetic information, and hydraulic characterization of pilot scale continuous disinfection processes, predictions of continuous process performance were made using a segregated flow model. These predictions were compared to independent experimental measurements of actual inactivation in pilot scale processes. Preainnioniation, free residual chlorination, and ozonation were used on two waters from Portland, Oregon (US). Organisms used were Giardia muris, bacteriophage MS2, and Escherichia coli.