Operation of a nitrite-type airlift reactor at low DO concentration.

摘要: Laboratory scale experiments were performed to evaluate the feasibility and potential of nitrite-type nitrification process with an airlift reactor having aerobic granular biomass. Oxygen limitation was selected as main control parameter for inhibiting growth nitrite oxidizer thus achieving only nitritation. To enhance granule formation, seeding methanogenic anaerobic granules used serve initial carrier material. After 90 days operation at low DO concentration less than 1.0 mg/l, maximum conversion rate 2.6 g NO2-N/L/d could be achieved. During continuing year-long stable operation, mass nitritation increased about 15 VSS/L average size 0.7 mm. Nitrate-N observed below 10 mg/L during whole operational period. From results experiments, it is concluded that a granule-type feasible