Composition of extracellular polymeric substances and microbial community structure in salt-tolerant aerobic granular sludge
Salt-tolerant aerobic granular sludge has the capability to degrade wastewater with extremely high salinity,yet the influence of sludge extracellular polymeric substances(EPS)and microbial community composition on granular sludge remains unclear.The cultivation of salt-tolerant aerobic granular sludge was investigated using three sequencing batch reactors(SBR)with different strategies:E for no salt addition and no sludge supplementation,A for intermittent salt addition and sludge supplementation,and S for intermittent salt addition without sludge supplementation.The influent salinity was set at 10%.The changes in sludge elemental content,EPS composition,and microbial community during the SBR operation were analyzed.It was found that the mass fraction of carbon and the total mass of amino acids in the sludge increased to 30.51%and 260.98mg/g(with hydrophobic at 94.46mg/g and hydrophilic at 166.52mg/g),respectively,under the intermittent sludge supplementation strategy.The enrichment of salt-tolerant phosphate-accumulating bacteria such as Halomonas(26.44%)and Corynebacterium(24.07%),as well as denitrifying bacteria from the unclassified_f_Rhodobacteraceae(10.82%),was observed.EPS and salinity were identified as the dominant factors inducing changes in the microbial community.The granulation duration of salt-tolerant granular sludge was shortened by gradual intermittent sludge supplementation,which ensure the stability of the sludge system and provide a new approach for the degradation of pollutants in high-salinity wastewater.
万方数据
维普
