好氧颗粒污泥处理印染废水的效能及微生物机制OA

This study investigated the effects of organic loading rate(OLR)on sludge granulation and pollutant removal performance of aerobic granular sludge(AGS)cultivated in a sequencing batch reactor(SBR)treating real printing and dyeing wastewater.After 60 days of cultivation,compact AGS with a particle size of～1 mm was successfully developed.The mature granules had an extracellular polymeric substances(EPS)content of 92.22 mg L-1 and achieved removal efficiency of 88.5%for COD and 73.3%for colority.OLR was found to be critical for sludge characteristics.At and OLR of 3.0 kg·(m3·d)-1,the AGS reached its maximum average particle size(1.38 mm),highest EPS content(95.21 mg·g-1),and optimal removal efficiencies for COD(92.73%)and colority(86.35%).However,an excessive OLR of 5.0 kg·(m3·d)-1 led to sludge bulking and disintegration.Microbial community analysis revealed Proteobacteria(44.06%～49.17%)and Bacteroidetes(27.49%～29.64%)as dominant phyla,whose abundance dynamics significantly correlated with protein-dominated EPS secretion and pollutant removal.These findings elucidated the mechanistic link between OLR-driven microbial community shifts,EPS production,and treatment performance,providing theoretical and technical support for the practical application of AGS in printing and dyeing wastewater treatment.