Instability of biological nitrogen removal in a cokes wastewater treatment facility during summer

  • Kim Y
  • Park D
  • Lee D
 et al. 
  • 29


    Mendeley users who have this article in their library.
  • 52


    Citations of this article.


Failure in nitrogen removal of cokes wastewater occurs occasionally during summer season (38 °C) due to the instability of nitrification process. The objective of this study was to examine why the nitrification process is unstable especially in summer. Various parameters such as pH, temperature, nutrients and pollutants were examined in batch experiments using activated sludge and wastewater obtained from a full-scale cokes wastewater treatment facility. Batch experiments showed that nitrification rate of the activated sludge was faster in summer (38 °C) than in spring or autumn (29 °C) and the toxic effects of cyanide, phenol and thiocyanate on nitrification were reduced with increasing temperature. Meanwhile, experiment using continuous reactor showed that the reduction rate in nitrification efficiency was higher at 38 °C than at 29 °C. In conclusion, the instability of full-scale nitrification process in summer might be mainly due to washing out of nitrifiers by fast growth of competitive microorganisms at higher temperature under increased concentrations of phenol and thiocyanate. © 2006 Elsevier B.V. All rights reserved.

Author-supplied keywords

  • Cokes wastewater
  • Nitrification
  • Pre-denitrification process
  • Temperature
  • Washing out

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free