title: Influence of volatile fatty acid concentration stability on anaerobic degradation of linear alkylbenzene sulfonate.
abstract: Linear alkylbenzene sulfonate (LAS) is an anionic surfactant used in cleaning products, which is usually found in wastewaters. Despite the greater LAS removal rate related to a lower concentrations of volatile fatty acids (VFA), the influence of different ranges of VFA on LAS degradation is not known. LAS degradation was evaluated in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors at different ranges of VFA concentrations. The reactors were fed with a synthetic wastewater containing LAS (14 mg/L). A greater LAS removal rate (40-80%) was related to the lower and narrower range of acetic acid concentration (1-22 mg/L) in the EGSB reactor. In the UASB reactor, the acetic acid concentrations presented a wider range (2-45 mg/L), and some low LAS removal rates (around 20-25%) were observed even at low acetic acid concentrations (<10 mg/L). The high recirculation rate in the EGSB reactor improved substrate-biomass contact, which resulted in a narrower range of VFA and greater LAS removal rate.
authors.affiliation: Depto. de Hidráulica e Saneamento, Escola de Engenharia de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense, No. 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: Juliana
authors.initials: J
authors.lastname: Polizel
authors.forename: Julia S
authors.initials: JS
authors.lastname: Hirasawa
authors.forename: Iolanda C S
authors.initials: IC
authors.lastname: Duarte
authors.forename: Maria B A
authors.initials: MB
authors.lastname: Varesche
mesh_terms: D019342:Acetic Acid / Q000737:chemistry; D017738:Alkanesulfonic Acids / Q000737:chemistry / Q000378:metabolism*; D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D019149:Bioreactors; D003902:Detergents / Q000737:chemistry / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000737:chemistry*; D012722:Sewage; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D019342:Acetic Acid; D017738:Alkanesulfonic Acids; D003902:Detergents; D005232:Fatty Acids, Volatile; D012722:Sewage; D062065:Wastewater; C030641:alkylbenzyl sulfonic acid
keywords: Acetic acid; Anaerobic; Detergent; Linear alkylbenzene sulfonate; Recalcitrant compound; Recirculation