Abstract
An anoxic biofilm involved in continuous denitrificationprocess was monitored to investigate the effect of differentconcentrations of influent dissolved oxygen (DO) or nitrite onthe biofilm. Microelectrode measurements evidenced nitrateremoval activity of biofilm. When different concentrations ofDO were applied to the reactor, generally decreasedconcentrations of DO were observed as bed depth increased fromthe bottom of the reactor. Greatest decrease of the DO wasobserved in the lower 20% of the bed depth. Nitrate removalefficiency was inversely proportional to influent DOconcentrations (8.3-11.9 DO mg L-1) or nitrite loadingrates (0-5.5 N-NO2 - kg m-3 day-1) employed in this study. Nitrite loading rates to achieve morethan 90% of nitrate removal efficiency were 1.46 N-NO2 -kg m-3 day-1 or less at pH 7.5 and 0.34 N-NO2 - kg m-3 day-1 or less at pH 6.8. Nitrate removal efficiency was 63% or more within the lower 20% of the bed depth at the nitrite loading rates that allowed more than 90% of nitrate removal efficiency of the reactor. The results of this study provide first quantitative data that nitrate removalperformance of an anoxic biofilm is inhibited by DO or nitrite,reported to be a limiting factor in the suspended biologicaldenitrification process.
Similar content being viewed by others
References
Almedia, J. S., Julio, S. M., Reis, M. A. M. and Carrondo, M. J. T.: 1995, 'Nitrite inhibition of denitrification by Pseudomonas fluorescens', Biotechnol. Bioeng. 46, 194-201.
Glass, C., Silverstein, J. and Oh, J.: 1997, 'Inhibition of denitrification in activated sludge by nitrite', Wat. Environ. Res. 69, 1086-1093.
Glass, C. and Silverstein, J.: 1998, 'Denitrification kinetics of high nitrate concentration water: pH effect on inhibition and nitrite accumulation', Wat. Res. 32, 831-839.
Hagedorn-Olsen, C., Moller, I. H., Tottrup, H. and Harremoes, P.: 1994, 'Oxygen reduces denitrification in biofilm reactors', Wat. Sci. Tech. 29, 83-91.
Halling-Sorensen, B. and Jorgensen, S. E.: 1993, The Removal of Nitrogen Compounds from Wastewater, Elsevier.
Kim, I. S., Stabnikova, E. V. and Ivanov, V. N.: 2000, 'Hydrophobic interactions within biofilms of nitrifying and denitrifying bacteria in biofilters', Bioprocess Eng. 22, 285-290.
Kornaros, M., Zafiri, C. and Lyberatos, G.: 1996, 'Kinetics of denitrification by Pseudomonas denitrificans under growth conditions limited by carbon and/or nitrate or nitrite', Wat. Environ. Res. 68, 934-945.
Lie, E. and Welander, T.: 1994, 'Influence of dissolved oxygen and oxidation-reduction potential on the denitrification rate of activated sludge', Wat. Sci. Tech. 30, 91-100.
Madigan, M. T., Martinko, J. M. and Parker, J.: 2000, Biology of Microorganisms, 9th Ed. Prentice Hall, New Jersey.
Metcalf and Eddy, Inc.: 1991, Wastewater Engineering: Treatment, Disposal and Reuse, 3rd Ed., McGraw-Hill, New York.
Mitchell, R.: 1992, Environmental Microbiology, John Willey & Sons, 290-293.
U.S. EPA: 1993, EPA Nitrogen Control, Technomic.
van Versefeld, H., Meiher, E. and Stouthamer, A.: 1977, 'Energy conservation during nitrate respiration on Paracoccus denitrificans', Arch. Microbiol. 112, 17-23.
Zhang, T. C. and Bishop, P. L.: 1994, 'Density, porosity and pore structure of biofilms', Wat. Res. 28, 2267-2277.
Zumft, W. G.: 1997, 'Cell biology and molecular basis of denitrification', Microbiol. Mol. Biol. Rev. 61, 533-616.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jang, A., Ahn, Y. & Kim, I.S. Monitoring the Impact of Dissolved Oxygen and Nitrite on Anoxic Biofilm in Continuous Denitrification Process. Environ Monit Assess 87, 133–144 (2003). https://doi.org/10.1023/A:1024698131900
Issue Date:
DOI: https://doi.org/10.1023/A:1024698131900