title: Chemical disinfection of combined sewer overflow waters using performic acid or peracetic acids.
abstract: We investigated the possibility of applying performic acid (PFA) and peracetic acid (PAA) for disinfection of combined sewer overflow (CSO) in existing CSO management infrastructures. The disinfection power of PFA and PAA towards Escherichia coli (E. coli) and Enterococcus was studied in batch-scale and pre-field experiments. In the batch-scale experiment, 2.5 mg L(-1) PAA removed approximately 4 log unit of E. coli and Enterococcus from CSO with a 360 min contact time. The removal of E. coli and Enterococcus from CSO was always around or above 3 log units using 2-4 mg L(-1) PFA; with a 20 min contact time in both batch-scale and pre-field experiments. There was no toxicological effect measured by Vibrio fischeri when CSO was disinfected with PFA; a slight toxic effect was observed on CSO disinfected with PAA. When the design for PFA based disinfection was applied to CSO collected from an authentic event, the disinfection efficiencies were confirmed and degradation rates were slightly higher than predicted in simulated CSO.
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs. Lyngby, Denmark.
authors.forename: Ravi Kumar
authors.initials: RK
authors.lastname: Chhetri
authors.affiliation: Udviklingssamarbejdet, c/o, Lynettefællesskabet, Refshalevej 250, 1432 Copenhagen, Denmark.
authors.forename: Dines
authors.initials: D
authors.lastname: Thornberg
authors.affiliation: Kemira Water Danmark A/S, G-vej 3, 2300 Copenhagen, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Berner
authors.affiliation: Kemira Kemi AB, Industrigatan 83, Box 902, 25109 Helsingborg, Sweden.
authors.forename: Robin
authors.initials: R
authors.lastname: Gramstad
authors.affiliation: Kemira Kemi AB, Industrigatan 83, Box 902, 25109 Helsingborg, Sweden.
authors.forename: Ulrik
authors.initials: U
authors.lastname: Öjstedt
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs. Lyngby, Denmark.
authors.forename: Anitha Kumari
authors.initials: AK
authors.lastname: Sharma
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs. Lyngby, Denmark. Electronic address: Henrik@ndersen.net.
authors.forename: Henrik Rasmus
authors.initials: HR
authors.lastname: Andersen
mesh_terms: D004202:Disinfectants / Q000032:analysis*; D004203:Disinfection / Q000379:methods*; D004323:Drainage, Sanitary / Q000379:methods; D005561:Formates / Q000032:analysis*; D010463:Peracetic Acid / Q000032:analysis*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology*; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D004202:Disinfectants; D005561:Formates; D010463:Peracetic Acid; D062065:Wastewater; D014874:Water Pollutants, Chemical; C008817:peroxyformic acid
keywords: Combined sewer overflow; Disinfection; Enterococcus; Escherichia coli; Peracetic acid; Performic acid