Skip to main content

Pilot-Scale Investigation to Achieve Very Low Nitrogen and Phosphorus Effluents by Retrofitting a University of Cape Town (UCT) Process

Buy Article:

$17.50 plus tax (Refund Policy)

Or sign up for a free trial

There are technologies for achieving very low nutrient levels during wastewater treatment, but since few facilities are currently operated to simultaneously remove nitrogen and phosphorus to very low levels, information is scarce on what effluent concentrations can be reliably achieved. We performed a pilot-scale study to evaluate reactor configurations and the amount of chemical additives needed to simultaneously achieve very low total nitrogen and total phosphorus levels in discharged effluents. Using a UCT-type process as a starting point, we modified the plant configuration to evaluate alternatives such as aerated-anoxic operation with step feeding for maximizing denitrification, and optimization of simultaneous nitrogen and phosphorus removal with methanol and alum as chemical supplements. Filtered and unfiltered samples were collected and analyzed to simulate the effect of filtration as a tertiary treatment.

In the absence of an external carbon source, it was difficult to substantially lower total nitrogen in the treated water. With methanol as an external carbon source, we were able to reach a total nitrogen concentration as low as 2.1 mgN/L. The distribution of nitrogen species in filtered effluents showed that the two largest contributors to the remaining nitrogen were nitrate and residual organic nitrogen. Phosphorus removal by a combination of biological and chemical processes, followed by filtration allowed reaching total phosphorus levels in the filtered effluent consistently below 0.4 mgP/L, with the best performance achieving a total phosphorus of 0.06 ± 0.02 mgP/L when there were high levels of alum, methanol, and internal recycle. Measurements of orthophosphate and total phosphorus in filtered effluents revealed that the majority of the phosphorus remaining in the effluent was not orthophosphate, but a residual fraction of non-readily reactive phosphorus.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Data/Media
No Metrics


Document Type: Research Article

Publication date: 2007-10-01

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
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