Effect of hydrocyclone on stability of aerobic granule sludge
水力旋流条件对好氧颗粒污泥稳定性影响

The morphology, diameter, the specific oxygen uptake rate and kinetic parameters of aerobic granular sludge in the new sequencing batch reactor (R1) and its contrasts (R2,R3) were analyzed and compared in this study. R1 used hydraulic cyclone flow condition to control the particle size and maintain granular sludge system stable. Results showed that increasing shear force could speed up the formation of granular sludge and the size increase, but the granule size could not be controlled. However, R1 with hydrocyclone had the same surface gas upflow velocity as R2 that can provide hydrocyclone shear force and friction force which may slow down the granulation process and control the granular diameter. The SOUR in R1, R2 and R3 were 0.80, 0.48 and 0.32 mg·h-1·mg-1, respectively, which proved that granular sludge is more active in the new reactor (R1). Kinetic parameters analysis showed that maintenance coefficient m and non-growth-related substrate consumption ratio Smin/CODinfluent in R1 were 0.13 h-1 and 9%, which were higher than R2 (0.077 h-1,9%) and R3 (0.084 h-1,1%). This indicated that hydraulic cyclone could effectively control the granular diameter and improve the stability of granular sludge system.