Inhibitory effect of sulfide on the nitrifying respiratory process
Article first published online: 12 DEC 2012
© 2012 Society of Chemical Industry
Journal of Chemical Technology and Biotechnology
Volume 88, Issue 7, pages 1344–1349, July 2013
How to Cite
Bejarano Ortiz, D. I., Thalasso, F., Cuervo López, F. d. M. and Texier, A.-C. (2013), Inhibitory effect of sulfide on the nitrifying respiratory process. J. Chem. Technol. Biotechnol., 88: 1344–1349. doi: 10.1002/jctb.3982
- Issue published online: 6 JUN 2013
- Article first published online: 12 DEC 2012
- Manuscript Accepted: 10 OCT 2012
- Manuscript Revised: 24 SEP 2012
- Manuscript Received: 26 JUL 2012
- respiratory process;
Biological wastewater treatment by nitrification is widely used; however information on inhibition of nitrification by sulfide is still scarce. The aim of this study was to evaluate the inhibitory effect of different initial sulfide concentrations on ammonium and nitrite oxidizing processes.
In the absence of sulfide, nitrification was completed after 24 h with an ammonium consumption efficiency (ENH4+) of 100.0 ± 2.1% and an ammonium to nitrate conversion yield (YNO3-) of 0.90 ± 0.01 g NO3--N g–1 NH4+-N consumed. At sulfide concentrations lower than 13.5 ± 0.7 mg HS--S L–1, ENH4+ was maintained at 100% after 60 h. At sulfide concentrations ranging from 3.1 to 112.0 mg HS--S L–1, the YNO3- decreased from 0.9 to 0.3 due to an accumulation of nitrite, whereas specific rates decreased by 51 to 92% for NH4+ consumption and by 77 to 97% for NO3- production. The IC50 value (concentration causing 50% inhibition) for ammonium and nitrite oxidation was 2.6 ± 0.3 and 1.2 ± 0.2 mg HS--S L–1, respectively.
Sulfide provoked an inhibitory effect on both ammonium and nitrite oxidizing processes, nitrite oxidation being the most affected step. This information is relevant for wastewater treatment, indicating that the presence of sulfide in effluents even at low concentration might strongly alter the nitrifying activity of activated sludge and provoke nitrite accumulation.© 2012 Society of Chemical Industry