The Effect of Biomass Particle Characteristics on the Sorption Hysteresis of 17α-Ethinylestradiol
The effects of particle characteristics on sorption and hysteresis of 17α-ethinylestradiol (EE2) were investigated in membrane bioreactor (MBR) and sequencing batch reactor (SBR). These results showed that the magnitude of the sorption partitioning coefficient depended on the particle specific surface area. This study also found that the sorption hysteresis index was greater for biomass suspensions with larger particle sizes. SRT did not prove to be an effective means of directly manipulating the biomass particle size, and the effects of SRT on the partitioning coefficient and the HI index, although present, were not dramatic. Nitrogen limitation did increase the hysteresis index values of the bioreactors when the SRT was 5 days; this result implies that it is possible to cause increased accumulation of EE2 in activated sludge floc during nitrogen limiting conditions.