Impact of Ozone and Hydrogen Peroxide vs. UV and Hydrogen Peroxide on Chlorine Residual

The current study undertaken by the Walkerton Clean Water Centre (WCWC) is to evaluate the application of Advanced Oxidation Processes (AOPs) involving Ozone and UV with the addition of hydrogen peroxide, as one of the methods used in the process of the removal of PPCPs and EDCs, or taste and odor. The amount of hydrogen peroxide used with UV is much higher than that used with the ozone application. The concern is the impact of the hydrogen peroxide on the chlorine residual in the water that is pumped to the distribution system. One of the methods used to deal with this problem is to increase the chlorine addition to maintain the required residual. That could increase the disinfectant by-products (DBPs), namely Trihalomethanes (THMs), in addition to increase to the cost of operation. The findings of these experiments would provide useful information regarding the AOPs application using ozone vs. UV with hydrogen peroxide.