title: Performance of a sequencing batch biofilm reactor for the treatment of pre-oxidized sulfamethoxazole solutions.
abstract: A combined strategy of a photo-Fenton pretreatment followed by a Sequencing Batch Biofilm Reactor (SBBR) was evaluated for total C and N removal from a synthetic wastewater containing exclusively 200 mg L(-1) of the antibiotic Sulfamethoxazole (SMX). Photo-Fenton reaction was optimized at the minimum reagent doses in order to improve the biocompatibility of effluents with the subsequent biological reactor. Consequently, the pretreatment was performed with two different initial H(2)O(2) concentrations (300 and 400 mg L(-1)) and 10 mg L(-1) of Fe(2+). The pre-treated effluents with the antibiotic intermediates as sole carbon source were used as feed for the biological reactor. The SBBR was operated under aerobic conditions to mineralize the organic carbon, and the Hydraulic Retention Time (HRT) was optimized down to 8h reaching a removal of 75.7% of the initial Total Organic Carbon (TOC). The total denitrification of the NO(3)(-) generated along the chemical-biological treatment was achieved by means of the inclusion of a 24-h anoxic stage in the SBBR strategy. In addition, the Activated Sludge Model No. 1 (ASM1) was successfully used to complete the N balance determining the N fate in the SBBR. The characterization and the good performance of the SBBR allow presenting the assessed combination as an efficient way for the treatment of wastewaters contaminated with biorecalcitrant pharmaceuticals as the SMX.
authors.affiliation: Department of Chemical Engineering, Faculty of Chemistry, University of Barcelona, Barcelona, Spain. ogonzalez@angel.qui.ub.es
authors.forename: Oscar
authors.initials: O
authors.lastname: González
authors.forename: Marc
authors.initials: M
authors.lastname: Esplugas
authors.forename: Carme
authors.initials: C
authors.lastname: Sans
authors.forename: Alicia
authors.initials: A
authors.lastname: Torres
authors.forename: Santiago
authors.initials: S
authors.lastname: Esplugas
mesh_terms: D000327:Adsorption; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology* / Q000592:standards*; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D009566:Nitrates / Q000737:chemistry / Q000302:isolation & purification; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry / Q000302:isolation & purification; D055668:Photochemical Processes; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012996:Solutions; D013420:Sulfamethoxazole / Q000378:metabolism*; D014865:Waste Disposal, Fluid
chemical_list: C045076:Fenton's reagent; D009566:Nitrates; D000644:Quaternary Ammonium Compounds; D012996:Solutions; D006861:Hydrogen Peroxide; D007501:Iron; D013420:Sulfamethoxazole; D010100:Oxygen