Pure Water Monterey: A Case Study for Ozone Sidestream Injection in Water Reuse Applications

Pure Water Monterey-a 30 MGD advanced water purification process that treats four sources of water for domestic, irrigation and aquifer recharge applications-provides an outstanding test of ozone sidestream injection to control a wide range of contaminants and maximize the efficacy of downstream treatment processes. Seasonal and source-related fluctuations in contaminants and volumes add to the challenge. Source flows include winter stormwater, agricultural runoff during the growing season, wastewater during the tourist high season, and vegetable processor rinse water in the summer and fall. This engaging case study will detail the role ozone plays at Pure Water Monterey in controlling pathogens, taste and odor compounds, and minerals across the wide range of source water contents and flows throughout the season. Data will illustrate how ozone contributes to improved performance of downstream filtration and polishing by reducing the size of organic particles, increasing their polarity, and enhancing their hydrophilicity. Improved downstream performance in MF, RO and UV/AOP is measured in run times and flux, intervals between cleaning, and consumption of backflush water and chemicals. The presenters will explore why Pure Water Monterey design engineers selected a sidestream injection system to deliver ozone. They will also detail how Mazzei used its historical engineering designs and computational fluid dynamics (CFD) modeling to help scale the sidestream injection system from its pilot installation to its two-flash-reactor plant design, and is now using those resources to guide plant expansion. Audience members will encounter three key take aways:

*How ozone uses its unstable third oxygen atom to quickly control pathogens, taste and odor compounds and other pollutants;

*Advantages of sidestream injection and pipeline flash reactors over fine bubble diffusers in terms of mass transfer, physical footprint, pumping energy, turndown and maintenance;

*Tips for optimizing transfer and mixing, piloting and scaling up sidestream injection systems for ozone delivery. Due to the diversity of its source water, the multiple uses of its treated water, and familiar downstream MF, RO and UV/AOC systems, Pure Water Monterey stands as a highly relevant case study for the use of ozone in municipal, agricultural and industrial water treatment.