title: Optimization of linear alkylbenzene sulfonate (LAS) degradation in UASB reactors by varying bioavailability of LAS, hydraulic retention time and specific organic load rate.
abstract: Degradation of linear alkylbenzene sulfonate (LAS) in UASB reactors was optimized by varying the bioavailability of LAS based on the concentration of biomass in the system (1.3-16 g TS/L), the hydraulic retention time (HRT), which was operated at 6, 35 or 80 h, and the concentration of co-substrates as specific organic loading rates (SOLR) ranging from 0.03-0.18 g COD/g TVS.d. The highest degradation rate of LAS (76%) was related to the lowest SOLR (0.03 g COD/g TVS.d). Variation of the HRT between 6 and 80 h resulted in degradation rates of LAS ranging from 18% to 55%. Variation in the bioavailability of LAS resulted in discrete changes in the degradation rates (ranging from 37-53%). According to the DGGE profiles, the archaeal communities exhibited greater changes than the bacterial communities, especially in biomass samples that were obtained from the phase separator. The parameters that exhibited more influence on LAS degradation were the SOLR followed by the HRT.
authors.affiliation: Department of Hydraulics and Sanitation, School of Engineering of São Carlos, University of São Paulo, Trabalhador São-carlense Avenue 400, 13566-590 São Carlos, SP, Brazil. dagokada@gmail.com
authors.forename: Dagoberto Y
authors.initials: DY
authors.lastname: Okada
authors.forename: Tiago P
authors.initials: TP
authors.lastname: Delforno
authors.forename: Andressa S
authors.initials: AS
authors.lastname: Esteves
authors.forename: Isabel K
authors.initials: IK
authors.lastname: Sakamoto
authors.forename: Iolanda C S
authors.initials: IC
authors.lastname: Duarte
authors.forename: Maria B A
authors.initials: MB
authors.lastname: Varesche
mesh_terms: D017738:Alkanesulfonic Acids / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001682:Biological Availability; D019149:Bioreactors / Q000382:microbiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009930:Organic Chemicals / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology*; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D017738:Alkanesulfonic Acids; D009930:Organic Chemicals; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical; C030641:alkylbenzyl sulfonic acid