Use of Ozone in Water Reclamation for Contaminant Oxidation

Client: WateReuse Foundation
Location: Alexandria, VA

Hazen and Sawyer is currently working with the Southern Nevada Water Authority on a project investigating the optimization of ozone in wastewater treatment for removal of trace organic contaminants, estrogenic activity, and total toxicity. We are performing a detailed cost analysis to evaluate the economic feasibility of full-scale ozone installations for wastewater.

Project Outcomes and Benefits

  • Bench-, pilot-, and full-scale optimization of ozone for contaminant destruction and disinfection.
  • Evaluation of DBP (i.e., NDMA and bromate) formation and mitigation strategies.
  • Identification of transformation products and their associated estrogenicity and toxicity.
  • Evaluation of aquifer recharge and recovery for the removal of oxidation byproducts, contaminants, and DBPs.
  • Comprehensive cost analysis to evaluate the economic feasibility of full-scale ozone installations.
  • Determine the underlying water quality parameters that can be used to predict ozone dose and efficacy (disinfection, contaminant oxidation) for any wastewater application.

Ozone diffusers installed in Henderson, NV.

This HiPOx unit (Ozone or Ozone/Peroxide, Provided by Applied Process Technology) is used for pilot testing at wastewater and reuse sites for contaminant destruction, disinfection, and minimization of disinfection byproduct formation potential.

40 GPM ozone pilot (Ozonia ozone generator and contactors) installed at Clark County Wastewater Reclamation District.

Hazen and Sawyer is participating in a Southern Nevada Water Authority ozone study funded by a grant from the WateReuse Foundation (WRF-08-05) scheduled to be complete in December, 2012.

The project seeks to :

  • Optimize the use of ozone in wastewater treatment by evaluating dose response relationships for disinfection and trace organic compound destruction
  • Evaluate DBP (i.e., NDMA and bromate) formation and mitigation; identify transformation products of trace contaminants; and asses the estrogenic activity and toxicity of the transformation products
  • Evaluate aquifer recharge and recovery for the removal of oxidation byproducts, recalcitrant trace organic contaminants, and DBPs
  • Compare pilot-scale pretreatment and ozonation technologies with full-scale ozone installations
  • Perform a comprehensive cost analysis to identify the most cost-effective strategy to incorporate ozone into wastewater treatment

For more information on this project, or to discuss a similar project in your area, contact

Ben Stanford, Ph.D. at bstanford@hazenandsawyer.com