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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.

Health effects, environmental impacts, and photochemical degradation of selected surfactants in water

“…The importance of sludge adaptation and mass transfer in the biodegradation process of LAS in activated sludge treatment was studied [55].…”

Health effects, environmental impacts, and photochemical degradation of selected surfactants in water

“…The importance of sludge adaptation and mass transfer in the biodegradation process of LAS in activated sludge treatment was studied [55]. A model was developed to analyze the effects of adsorption and biodegradation kinetics on the fate of LAS in batch experiments with activated sludge adapted to different initial LAS concentrations.…”

Effects of pilot‐plant photochemical pre‐treatment (UV/H2O2) on the biodegradability of aqueous linear alkylbenzene sulfonate (LAS)

“…LAS has also shown inhibitory effects on the anaerobic biological treatment [7,8]. It has been reported that LAS with the concentrations of less than 10 mg/L is biodegradable under aerobic activated sludge treatment and its degradation follows Monod's equation over the ranges of 0.1-20 mg/L [9]. Moreover, it has been reported that the fate of LAS can follow first order kinetics for the similar ranges of concentrations [10].…”