title: Post-treatment of biologically treated wastewater containing organic contaminants using a sequence of H2O2 based advanced oxidation processes: photolysis and catalytic wet oxidation.
abstract: In this paper the feasibility of a multi-barrier treatment (MBT) for the regeneration of synthetic industrial wastewater (SIWW) was evaluated. Industrial pollutants (orange II, phenol, 4-chlorophenol and phenanthrene) were added to the effluent of municipal wastewater treatment plant. The proposed MBT begins with a microfiltration membrane pretreatment (MF), followed by hydrogen peroxide photolysis (H2O2/UVC) and finishing, as a polishing step, with catalytic wet peroxide oxidation (CWPO) using granular activated carbon (GAC) at ambient conditions. During the microfiltration step (0.7 μm) the decrease of suspended solids concentration, turbidity and Escherichia coli in treated water were 88, 94 and 99%, respectively. Also, the effluent's transmittance (254 nm) was increased by 14.7%. Removal of more than 99.9% of all added pollutants, mineralization of 63% of organic compounds and complete disinfection of total coliforms were reached during the H2O2/UVC treatment step (H2O2:TOC w/w ratio = 5 and an UVC average dose accumulated by wastewater 8.80 WUVC s cm(-2)). The power and efficiency of the lamp, the water transmittance and photoreactor geometry are taken into account and a new equation to estimate the accumulated dose in water is suggested. Remaining organic pollutants with a higher oxidation state of carbon atoms (+0.47) and toxic concentration of residual H2O2 were present in the effluent of the H2O2/UVC process. After 2.3 min of contact time with GAC at CWPO step, 90 and 100% of total organic carbon and residual H2O2 were removed, respectively. Also, the wastewater toxicity was studied using Vibrio fischeri and Sparus aurata larvae. The MBT operational and maintenance costs (O&M) was estimated to be 0.59 € m(-3).
authors.affiliation: Department of Environmental Technologies, Faculty of Marine and Environmental Sciences, Cadiz University, Avda. República Saharaui S/N, Puerto Real, 11510, Cádiz, Spain. Electronic address: juanjose.rueda@uca.es.
authors.forename: J J
authors.initials: JJ
authors.lastname: Rueda-Márquez
authors.affiliation: Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50100, Mikkeli, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Sillanpää
authors.affiliation: R&D Department, Abengoa Water, C/ Don Redondo, Dos Hermanas, 41703, Seville, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Pocostales
authors.affiliation: Department of Environmental Technologies, Faculty of Marine and Environmental Sciences, Cadiz University, Avda. República Saharaui S/N, Puerto Real, 11510, Cádiz, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Acevedo
authors.affiliation: Department of Environmental Technologies, Faculty of Marine and Environmental Sciences, Cadiz University, Avda. República Saharaui S/N, Puerto Real, 11510, Cádiz, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Manzano
mesh_terms: D048908:Aliivibrio fischeri; D000818:Animals; D001391:Azo Compounds / Q000737:chemistry; D001557:Benzenesulfonates / Q000737:chemistry; D002384:Catalysis; D002733:Chlorophenols / Q000737:chemistry; D004203:Disinfection; D006861:Hydrogen Peroxide / Q000737:chemistry*; D010084:Oxidation-Reduction; D010616:Phenanthrenes / Q000737:chemistry; D019800:Phenol / Q000737:chemistry; D010782:Photolysis; D021541:Sea Bream; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects / Q000633:toxicity; D018508:Water Purification / Q000379:methods*
chemical_list: D001391:Azo Compounds; D001557:Benzenesulfonates; D002733:Chlorophenols; D010616:Phenanthrenes; D014874:Water Pollutants, Chemical; D019800:Phenol; C029107:4-chlorophenol; C031181:phenanthrene; D006861:Hydrogen Peroxide; C014722:2-naphthol orange
keywords: AOP; Accumulated UVC dose; Disinfection; Operational cost; Toxicity test; UVC dose equation