Effects of the influent ammonium nitrogen concentration on nitrite accumulation in a biological nitritation process

Nitrogen is one of the primary elements that causes eutrophication. In recent years, more stringent environmental standards have come into effect, and nitritation processes have been promoted as a way to remove the high nitrogen content of recycle water and piggery wastewater, which have extremely high ammonium nitrogen concentrations. In this study, the effects of different influent ammonium nitrogen concentrations were evaluated with respect to the rate of nitritation. The influent ammonium nitrogen concentrations ranged from 286 to 2,620 mg/L, so the nitritation reactor was operating under fluctuating ammonium nitrogen concentrations during the experimental period. In the experiment, stable nitritation rates were observed under varying ammonium nitrogen concentrations. Methods to control the influent ammonium nitrogen concentrations were assessed for wastewater with fluctuating ammonium nitrogen concentrations. Nitritation was found to be useful process for removing nitrogen from wastewater with high nitrogen content; additionally, nitritation provides an economic advantage over nitrification.