Acetate uptake efficiency of polyphosphate-accumulating organisms under exposure to surfactants

摘要

We investigated the influence of surfactants such as linear alkylbenzene sulfonates (LAS) andnalcohol ethoxylates (AE) on acetate uptake by polyphosphate-accumulating organisms (PAOs)nunder anaerobic conditions, using the phosphate requirement for acetate uptake (+DP/2DAcnratio). In order to estimate the +DP/2DAc ratio, anaerobic batch tests were conducted usingnactivated sludge collected from an anaerobic/oxic sequencing batch reactor used to treatnmunicipal wastewater continuously supplemented with a detergent containing LAS and AE.nWe demonstrated that LAS and AE have both positive and negative impacts on acetate uptake bynPAOs. The disadvantage is that long-term exposure to the detergent inhibits acetate uptake bynPAOs, thus deteriorating the efficiency, even if the surfactants are no longer present during thentests. Furthermore, the existence of LAS and/or AE with acetate further diminishes the efficiency.nThe advantage is that LAS and AE are potential sources of polyhydroxyalkanoate for PAOs,nbecause acetate is produced from the surfactants under anaerobic conditions.