Study on Temperature Influence on Nitrogen Removal Properties in Anammox
The nitrogen removal and period tending to be stable of anammox under the temperature 37, 35, 30, 25 and 20 were investigated in a packed-bed anammox biofilm reactor which had already operated stably for 300 days. It was found that the highest NRR(nitrogen removal rate)-75.4% and the shortest variation period of effluent concentration-4h was obtained at 37 °C while the opposite results of the lowest NRR of 48.7% and the longest period of 8h was appeared at 20°C; The inhibition effect at high temperature was investigated: the nitrogen removal rate decreased at the temperature of more than 40°C and drop rapidly to 10% when the temperature increased closed to 60°C. The results of the experiments above showed that the nitrogen removal of anammox can be greatly influent by temperature: from 33 to 37°C was the suitable temperature; the NRR decreases under 30°C and the capable to adapt variation drop with the temperature falling. The NRR decreased under high temperature (more than 40°C) and plenty of anammox died in a short time at 60°C.