EAPSI: Identifying the feasibility and cost effectiveness of ozone as a treatment technology in water reuse systems

Marti Erica J, Las Vegas NV

Investigators

Abstract

Water reuse refers to the advanced treatment of wastewater for intentional reuse options, such as irrigation or drinking water, and it is usually associated with water scarcity. Some water contaminants occur as a result of disinfection. N- Nitrosodimethylamine (NDMA) is one of those contaminants of particular concern for potable water reuse as drinking water, since it is believed to be a carcinogen or cancer-causing agent. This research will investigate the use of ozone to reduce NDMA formation in water reuse systems. Australia is a leader in water reuse projects, which is in part due to their arid climate and limited water supply. This research will be conducted in collaboration with Drs. Jeff Charrois and Cynthia Joll, who are noted experts on NDMA and water reuse, at Curtin University in Australia. Ozone is an effective treatment for disinfection, non-selective destruction of potentially harmful organic compounds, and removal of taste, odor and color. However, some treated wastewaters contain compounds that react with ozone to directly form NDMA during treatment. Since the compounds or precursors that form NDMA with ozonation are not well established, the only way to determine the potential for NDMA formation is through direct testing. At this time, Australian water reuse projects do not use ozone as a treatment step. The aims of this research are to 1) determine the potential of Australian wastewaters for direct NDMA formation with ozone, 2) investigate pre-chlorination as a strategy to reduce NDMA formation with ozone, and 3) evaluate the cost and efficiency of different water reuse treatment scenarios, with and without ozone, for NDMA removal. This NSF EAPSI award is funded in collaboration with the Australian Academy of Science.