Granular sludge was first reported for an anaerobic, upflowanaerobic sludge blanket (UASB) process to treat industrialwastewaters at the end of the 1970s [1]. As anaerobic techniquesmight generate unpleasant odors and cause secondary pollutionin many cases, alternative aerobic biodegradation has increasinglyattracted research interest [2]. Aerobic granular sludge was foundin an aerobic UASB by Mishima and Nakamura [3]. Furthermore,it has been developed under aerobic conditions and mainly usedfor the aerobic degradation of organics but also for the removal ofnitrogen under aerobic and anoxic conditions in the treatment ofvarious municipal and industrial wastewaters [4].