Influence of ferric iron dosing on aerobic granular sludge: granule formation, nutrient removal and microbial community

Abstract BACKGROUND Three lab‐scale sequencing batch reactors were used to investigate the effects of Fe 3+ on aerobic granular sludge (AGS) formation, nutrient removal, and microbial community. RESULTS The addition 6 12 mg L −1 could not shorten granulation time. However, compared reactor without (average volume index at 30 min (SVI ) 70.8 mL g ; stable average particle size 548 μm), helped improve physical properties AGS SVI 57.0 1067 μm). Furthermore, with (Fe PO 4 3− ‐P molar ratio = 1.33), effective removal NH + ‐N (≤0.5 (<1 was achieved. reduced diversity specific activity heterotrophic bacteria, but promoted growth nitrite‐oxidizing bacteria. only increased active biomass diversity, alleviated inhibition effect bacteria activity. CONCLUSION had both negative positive formation stability AGS. results will help enrich understanding application in especially that phosphorus. © 2020 Society Chemical Industry