Impact of Bromate Control on Ozone Oxidation/Disinfection and Downstream Treatment Processes in Potable Reuse

During ozonation of wastewater, treatment goals for disinfection and contaminant oxidation must be balanced carefully with the formation of disinfection byproducts (DBPs), such as bromate. Mitigation strategies (e.g., pH depression, ammonia, hydrogen peroxide, etc.) have been studied in drinking water, and involve bromide sequestration and manipulating the ozone/hydroxyl radical pathways away from bromate formation. However, these control strategies may also impact treatment goals for disinfection and contaminant oxidation. As a result, more robust data sets are needed to evaluate the common chemical control strategies in reuse water and their impact on ozone process efficiency and downstream biofiltration performance. This project will review bromate formation mechanisms, chemical control techniques, design considerations, and upstream/downstream process considerations offering a holistic approach to bromate management in treatment plants. Further analysis will include development and refinement of ozone demand/decay and bromate formation models that will allow utilities to better balance bromate with disinfection/oxidation objectives.

Three articles focused on this research have already been published:

• Ozone Disinfection of Waterborne Pathogens and their Surrogates: A Critical Review
• Empirical Modeling of Bromate Formation and Chemical Control Strategies at Multiple Water Reuse Facilities Using Ozone
• Critical Review on Bromate Formation during Ozonation and Control Options for Its Minimization