Rapid cultivation of aerobic granular sludge and influence of extracellular polymeric substances on granulation

The cultivation of aerobic granular sludge in three sequencing batch reactors by seeding different kinds of sludge, including: common activated sludge, aerobic granular sludge and anaerobic granular sludge respectively was investigated, the granulation process and the time to complete of the three under the same operation condition were compared; the influence of extracellular polymeric substances on the aerobic sludge granulation was studied at the same time. The results showed that, the time needed for the formation of granulation could be greatly shortened by adding some aerobic granular sludge beforehand, it also indicated that, extracellular polymeric substances was closely related to sludge granulation.