Nitrite Levels in an Incomplete Nitrifying Plant, and How Increasing Denitrification Could Decrease Nitrite and Disinfection Issues

$17.50 plus tax (Refund Policy)

Buy Article:

Abstract:

Nitrite levels above 1 ppm in the secondary clarifier effluent require increased doses of chlorine for disinfection. An incomplete nitrifying plant was studied for 1 year and the causes of increased nitrite levels in the secondary clarifier effluent coincided with high concentrations of ammonia oxidizing bacteria (AOB) and total bacteria (TB). When Nitrospira was present in concentrations near 1013 cells per liter and when Nitrospira and Nitrobacter were both greater than 1012 cells per liter effluent concentrations were below 1 ppm nitrite. When increased to >109 copies per liter, nitrite increased in both the aeration tank and the secondary clarifier effluent. During chlorination of the foaming event, the concentration in the effluent increased. When AOB growth rate started to increase in March and heterotrophic growth rate in April concentration of nitrite increased in the aeration tank, which was followed by increased nitrite in the secondary clarifier effluent until mid-June. Experiments were conducted to determine if recycle of a percentage the aeration tank mixed liquor would help to decrease nitrite levels. However, the experiments with aeration tank volumes (10, 20 and 50%) combined with anoxic zone volumes (90, 80 and 50%) produced mixed results, which corresponded with the finding that denitrification although greatest in the summer only periodically decreased nitrite levels in the aeration tank.

Keywords: AOB; Incomplete nitrifying plant; NOB; Nitrite accumulation; Nitrite reduction experiment

Document Type: Research Article

DOI: http://dx.doi.org/10.2175/193864711802639318

Publication date: January 1, 2011

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 These proceedings are not peer reviewed.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • ingentaconnect is not responsible for the content or availability of external websites

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect 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