title: How adaptation and mass transfer control the biodegradation of linear alkylbenzene sulfonate by activated sludge.
abstract: We use a nonsteady-state model to evaluate the effects of community adaptation and sorption kinetics on the fate of linear alkylbenzene sulfonate (LAS) in batch experiments conducted with activated sludge that was continuously fed different concentrations of LAS. We observed a sharp decrease in the biodegradation rate between 30 and 60 minutes and the presence of an LAS residual at the end of the batch experiments. The modeling analysis indicates that these phenomena were caused by relatively slow inter-phase mass transport of LAS. The modeling analyses also showed that the amount of LAS-degrading biomass increased when the continuous activated sludge was fed a higher LAS concentration. Although community adaptation to LAS involved accumulation of more LAS degraders, the increase was not proportional to the feed concentration of LAS, which supports the concept that LAS degraders also utilized portions of the general biochemical oxygen demand (BOD) fed to the continuous activated sludge systems.
authors.affiliation: Department of Civil and Chemical Engineering, Northwestern University, Evanston, IL 60208-3109, USA.
authors.forename: B E
authors.initials: BE
authors.lastname: Rittmann
authors.forename: P
authors.initials: P
authors.lastname: Tularak
authors.forename: K C
authors.initials: KC
authors.lastname: Lee
authors.forename: T W
authors.initials: TW
authors.lastname: Federle
authors.forename: N R
authors.initials: NR
authors.lastname: Itrich
authors.forename: S K
authors.initials: SK
authors.lastname: Kaiser
authors.forename: J
authors.initials: J
authors.lastname: Shi
authors.forename: D C
authors.initials: DC
authors.lastname: McAvoy
mesh_terms: D017738:Alkanesulfonic Acids / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology; D004785:Environmental Pollutants / Q000378:metabolism; D007700:Kinetics; D008954:Models, Biological; D012722:Sewage / Q000382:microbiology*
chemical_list: D017738:Alkanesulfonic Acids; D004785:Environmental Pollutants; D012722:Sewage; C030641:alkylbenzyl sulfonic acid