Skip to main content

30 YEARS OF EXPERIENCE USING OZONE IN THE UNITED STATES DISINFECTING WASTEWATER

Buy Article:

$17.50 plus tax (Refund Policy)

Or sign up for a free trial

Abstract:

This paper reviews the use of ozone as a disinfectant for wastewater over the last 30 years. A historical usage profile of ozone disinfection by Publicly Owned Treatment Works (POTWs) is presented along with some insights focused on the evolution of ozone generation equipment and ozone transfer and contactor design.

The historical usage profile was developed from the literature and work performed by a project team of Kennedy/Jenks Consultants, Los Angeles County Sanitation Districts, and the California State University, Fullerton that was awarded the Water Environment Federation Research Foundation Project, Disinfection of Wastewater Effluent — Comparison of Alternative Technologies (04-HHE-4) in August 2005. One of the project tasks to accomplish this goal was to perform a survey of disinfection practice by major POTWs.

For this study, the USEPA definition of a major POTW was used and is defined as a sewage treatment facility that is owned by a state or municipal agency and has an average dry weather design flow treatment capacity of at least 1 MGD. Using several databases that included the US Census and two USEPA databases (one called the Clean Water Needs Survey (CWNS), and the other called Envirofacts that is used by the NPDES system), approximately 4,450 major POTWs were identified in the 50 US states and the District of Columbia.

The historical use pattern by the wastewater industry is constrasted to the drinking water treatment industry. The comparison shows that wastewater was an early adapter of ozonation, but quickly stopped its use whereas the opposite is true of the water treatment industry. It is estimated that 25 percent of all the surface drinking water treatment plant ≥ 1 MGD in the US use ozone today.

Historically, as many as 50 wastewater treatment plants (POTWs), including 32 major POTWs were equipped to use ozone as a disinfectant as well as to meet additional treatment goals. In 1989 15 major POTWs had the equipment, but were not operating their ozone facilities whereas 17 major POTWs were using this technology. In 2006 this number has dropped to seven POTWs using ozone. During the project survey, three POTWs indicated that they are planning replace their original ozone generators to continue using ozone and four others are in design or planning stages to change to using ozone as their disinfectant.

A telephone survey of the POTWs that have or are using ozone indicate that there were various reasons that POTWs have and are selecting ozone as a disinfectant. Generally, there are site specific reasons that include, but are not limited to the following:



Disinfection


Removing color


Improving dissolved oxygen (DO) in a receiving water


Providing an additional treatment barrier for reuse


Removing endocrine disruptors and pharmaceutical active agents


Many of the early ozone systems experienced premature equipment failures and problems associated with what were then a developing ozone generation technology. The paper will discuss the extensive increase in the use of ozone in the water treatment industry during the same 30 year period, and significant advances in ozone generator design and operating efficiency, as well as advances in ozone transfer efficiency and ozone contactor design. These improvements will provide significant benefits to POTWs considering use of ozone as their disinfectant.

Document Type: Research Article

DOI: https://doi.org/10.2175/193864707787932621

Publication date: 2007-01-01

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Learn about the many other WEF member benefits and join today
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more