Secondary Effect of Oxygen Limitation on the Distribution of the Products of Nitrification during Wastewater Treatment

Abstract

Within the frames of this experiment, a secondary effect of oxygen limitation during reject water treatment on the distribution of the nitrification final products was demonstrated. This effect consists in extreme increase of nitrite concentration as the consequence of nitrite-oxidising bacteria inhibition induced primarily by the lack of oxygen. Subsequently, a toxic effect of nitrite (or more precisely free nitrous acid) is able to stop the nitrification process on a nitrite level under specific technological arrangement of treatment process even in the case that oxygen limitation is terminated. The results could be used for the control of nitrification process during the operation of biological reactors applying ANAMMOX process or nitritation/denitritation method for the treatment of specific types of wastewaters.