title: Aerobic degradation of 2,4,6-TCP content in ECF bleached effluent.
abstract: Elemental chlorine-free (ECF) bleach effluents from kraft mill are characterised by: a chemical organic demand/biological organic demand (COD/BOD(5)) ratio of 4, chlorophenol content with low chlorine substitution, and toxicity. The effect of increasing the concentration of 2,4,6-trichlorophenol (2,4,6-TCP) content in ECF bleaching sequence effluent on the degradative activity of bacterial communities present in an aerobic system treatment was studied. An aerobic lagoon (AL) was used as a typical secondary treatment of kraft-mill effluent. AL displays a high performance of BOD(5) degradation (up to 90%); however, only 40% of the COD was removed. Simultaneously, the AL system shows a high ability to biodegrade 2,4,6-TCP up to 237 mg/l day. Kinetic parameters of the 2,4,6-TCP biodegradation by aerobic bacteria were determined. The K(s) and K(i) values were 34.3 and 50 mg/l 2,4,6-TCP, respectively. Moreover, the tolerance of aerobic bacteria was observed up to 1.3 g/l 2,4,6-TCP.
authors.affiliation: Department of Microbiology, Biological Sciences Faculty, University of Concepción, PO Box 160-C, Concepcion, Chile.
authors.forename: J
authors.initials: J
authors.lastname: Correa
authors.forename: V M
authors.initials: VM
authors.lastname: Domínguez
authors.forename: M
authors.initials: M
authors.lastname: Martínez
authors.forename: G
authors.initials: G
authors.lastname: Vidal
mesh_terms: D001420:Bacteria, Aerobic; D001673:Biodegradation, Environmental; D002733:Chlorophenols / Q000378:metabolism*; D007220:Industrial Waste; D007700:Kinetics; D009153:Mutagens / Q000378:metabolism*; D010209:Paper; D018508:Water Purification
chemical_list: D002733:Chlorophenols; D007220:Industrial Waste; D009153:Mutagens; C024564:2,4,6-trichlorophenol