Keywords: activated sludge, aerobic granulation, ash-solids fraction, extending feeding time, granular sludge, granule update, sequence batch reactors, SBR, size distribution, substrate gradient, stability, wastewater treatment, granule size, biomass
Effect of extended feeding time on aerobic granulation in SBR
Two different feeding lengths were applied to control the granule size. It was found that the size of granules was considerably controlled in R2 (60 min for feeding). However, the settleability in R2 was not as good as that in R1 (12 min for feeding). However, this approach of controlling the granule size also loosens the structure concerning on the difference between SVI5 and SVI30, which might lead to instability in the long term. Based on the observation of the ash-solids fraction of biomass, it was confirmed that frequent update of granules mainly happened on the surface of granules.