Effects of aeration on the activity and nutritional component of bio-flocs in sequencing batch reactor

Aquacultural solid waste was used to culture bio-flocs in sequencing batch reactor. Continuous aeration and intermittent aeration modes were set up to study effects of aeration on the activity and nutritional components of bio-flocs in sequencing batch reactor. Results showed that intermittent aeration tended to inhibit the nitrification process with average nitrite concentration of 0.93(依0.26) mg/L and nitrate concentration of 0.90(依0.21) mg/L throughout the experimental period. In continuous aeration treatment, high accumulation of nitrite and nitrate was observed across the trial, the concentrations of nitrite and nitrate were 8.68 mg/L and 20.78 mg/L, respectively, at the end of experiment. The percentage of organic nitrogen to total nitrogen (TON/TN) of bio-flocs increased gradually in intermittent aeration sequencing batch reactor with an average of 81.85(依1.27)%, while a decreasing treand was observed in the continuous aeration group with an average of 61.11(依4.30)%. In intermittent aeration treatment, the maximum concentration of protein content was 34.38 (依0.15)% and in continuous aeration sequencing batch reactor, was 28.59 (依3.50)%. Average protein content of bio-flocs was 5.85 (依0.26)% higher in the intermittent aeration group than that in continuous aeration group.