Study on the cultivation of aerobic gtanular sludge in SBR reactor

The experimental study of aerobic granular sludge in a sequencing batch reactor (SBR) was performed using synthetic domestic wastewater and ordinary flocculent activated sludge as seeding sludge. The conditions under which the successful cultivation of aerobic granular sludge was done are as follows: the temperature is room temperature, pH is about 7.0, aeration time is 150 ~ 180 min, sludge settling time is 9 ~ 120 min, and aeration rate 0.3 ~ 0.5 m3/h. The aerobic granular sludge has yellow appearance, with a size of 1 ~ 2 mm, SVI of 40 mL/g or so, and MLSS of 6515 mg/L. The average settling velocity is up to 18.42 m/h. Aerobic granular sludge contains large amounts of protozoa and metazoan which emerge in groups. The removal rates of COD, TN and TP is respectively up to 95%, 96% and 98%.