Screening of an Aerobic Denitrifying Bacteria and Treatment of Anaerobic Digestion Piggery Effluent.

A strain of aerobic denitrifying bacteria was isolated and purified from the activated sludge and numbered AHP123, identified as Acinetobacter sp. by 16S rDNA sequencing analysis. The strain could effectively remove NH₄⁺-N and NO₃^--N, showing well heterotrophic nitrification and aerobic denitrification ability. The results of single factor condition optimization showed that under the conditions of C/N 20, sodium succinate as carbon source, rotation speed 200 r/min, temperature 30 °C, inoculation rate 2% and NH₄⁺-N as single nitrogen source, the NH₄⁺-N removal efficiency achieved 99.26% in 24 h and the removal rate was 4.86 mg/(L½h). Under the conditions of C/N 20, sodium citrate as carbon source, rotation speed 120 r /min, temperature 25 °C, inoculation rate of 2% and NO₃^--N as single nitrogen source, the NO₃^--N removal efficiency achieved 92.68% in 24 h and the removal rate was 6.11 mg/(L·h). When NH₄⁺-N and NO₃^--N were used as mixed nitrogen sources, the removal efficiencies of NH₄⁺- N and NO₃^--N reached 98.64% and 80.38%, respectively. Furthermore, strain AHP123 showed good application effect in the treatment of anaerobic digestion piggery effluent (ADPE) containing nitrogen. After 48 h of treatment, the removal efficiency of NH₄⁺-N in ADPE reached 99.19%. [ABSTRACT FROM AUTHOR]