[Effect of trace NO2 and kinetic characteristics for anaerobic ammonium oxidation of granular sludge].

The effect of trace NO2 and kinetic characteristics for anaerobic ammonium oxidation of granular sludge was investigated by batch experiment. The sludge anammox rates could be described by the Haldane model. The kinetic parameters were determined, where the maximum anammox rate was 6.65 x 10(-3) mg (mg h)(-1). The half saturate coefficient and inhibition coefficient for ammonium nitrogen were 87.1 mg L(-1) and 1,123 mg L(-1) respectively, and the half saturate coefficient and inhibition coefficient for nitrite nitrogen were 15.39 mg L(-1) and 159.5 mg L(-1) respectively. Trace NO2 apparently enhanced anammox under trace NO2 atmosphere conditions. The function for NO2 to enhance anammox was suggested by the Haldane based model. The parameters in the function were estimated, where the maximum enhancing anammox coefficient was 48.79, and the half saturate coefficient and inhibition coefficient for NO2 were 2480 mg m(-3) and 4.22 mg m(-3) respectively, and the basic rate coefficient was 0.0182. The most of NOx in the experiment was lost.