Denitrification of nitrite-nitrogen carried out experimentally in an anoxic two-phase fluidized bed bioreactor is described, and the characteristics of the biological treatment were also theoretically studied. Methanol was used as the carbon source, and nitrite-degrading bacteria immobilized on CB particles were employed. A method for evaluating the characteristics of the biological treatment is proposed. Within the range of the experiment, the results show that denitrification of nitrite-nitrogen could be approximated by Monod-type reaction kinetics, characteristic values for the biological treatment of Ku = 5.0 kg-N·kg−1-VS·d−1 and Ku/Km = 23.8 m3·kg−1-VS·d−1 being obtained. There was good correlation between the experimental results and the calculated curves. A maximum volumetric denitrification rate for nitrite of 18.7 kg-N·m−3·d−1 was achieved, this high value demonstrating the high efficiency of an anoxic two-phase fluidized bed bioreactor to denitrify nitrite-nitrogen.

This content is only available as a PDF.