Rapid granulation of aerobic granular sludge in an integrated moving bed biofilm reactor-membrane bioreactor: Effects and mechanism of Streptomyces cellulosus microspheres

This work focuses on revealing the effects of functional microorganism on rapid granulation process of aerobic granular sludge (AGS) in an integrated moving bed biofilm reactor-membrane bioreactor (MBR), and tries to illustrate the related mechanism. The result verified that the functional microorganism, Streptomyces cellulosus microspheres (Scms), could promote the rapid granulation of AGS within only 4 days, and the average size of AGS kept at around 1850 mu m on day 80 and showed no obvious reduction in the size even for operating over 3 months. Scms first reduced the negative surface charge on sludge particles, which was beneficial to the aggregation of floc sludge, and then caused the changes in the structure of AGS and the composition of microbial community within the system. Under these effects, the formed large and stable AGS promoted a higher and more stable efficiency in the removal of COD (> 93 %).