Heterotrophic nitrification and aerobic denitrification bacterium isolated from anaerobic/anoxic/oxic treatment system

Abstract

A special strain of Alcaligenes denitrificans, designated as WY200811, with heterotrophic nitrification and aerobic denitrification ability was novel isolated from an anaerobic/anoxic/oxic treatment system and characterized. The average ammonia nitrogen (NH₄⁺-N) and TN (total nitrogen) removal rates of the strain were 0.026 and 0.028 gN/g·Cell·h. Under the environmental conditions of 22% DO and C/N ratio of 5, the ultimate efficiencies of nitrification and denitrification were 57.0 and 57.3%, respectively. The pH in the medium was maintained between 6.0 and 7.0. The novel strain can rapidly reduce the ammonia to nitrogen gas without nitrite accumulation. The WY200811 can be used in a full-scale anaerobic/anoxic/oxic treatment system for efficiency in heterotrophic nitrification and aerobic denitrification.

Key words: Heterotrophic nitrification and aerobic denitrification, Alcaligenes denitrificans, nitrogen balance.