title: Reducing effect of aerobic selector on the toxicity of synthetic organic compounds in activated sludge process.
abstract: The effects of phenol, 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP) and 1,2,4-trichlorobenzene (1,2,4-TCB) on the biodegradation kinetics of the conventional activated sludge system (CASS) and the selector activated sludge system (SASS) were investigated. Experiments were carried out using a respirometric method on unacclimated biomass from two lab-scale systems that were operated with the sludge age of 8 days. Toxicity of the test compounds for both reactors were arranged according to EC(50) (effective concentration) values in order as: 1,2,4-TCB>2,4-DCP>2-CP>phenol. All selected test compounds induced higher inhibition effect in the CASS. The SASS appeared to reduce inhibition effect in comparison to the CASS, by 21.36%, 66.95%, 64.37% and 33.33% for phenol, 2-CP, 2,4-DCP and 1,2,4-TCB, respectively. Consequently, the SASS may be recommended as a promising configuration alternative for the waste streams containing toxic compounds.
authors.affiliation: Department of Environmental Engineering, Faculty of Engineering and Architecture, Uludag University, 16059 Bursa, Turkey. sceleren@uludag.edu.tr
authors.forename: Sevil Calişkan
authors.initials: SC
authors.lastname: Eleren
authors.forename: Ufuk
authors.initials: U
authors.lastname: Alkan
mesh_terms: D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D002722:Chlorobenzenes / Q000032:analysis / Q000302:isolation & purification*; D002733:Chlorophenols / Q000032:analysis / Q000302:isolation & purification*; D007700:Kinetics; D009930:Organic Chemicals / Q000032:analysis; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods
chemical_list: D002722:Chlorobenzenes; D002733:Chlorophenols; D009930:Organic Chemicals; D012722:Sewage; C009947:1,2,4-trichlorobenzene; C030683:2-chlorophenol; C004762:2,4-dichlorophenol