title: Pentachlorophenol aerobic removal in a sequential reactor: start-up procedure and kinetic study.
abstract: This study has demonstrated the applicability of a simple technology such as the sequencing batch reactor (SBR), operated with suspended biomass, to the aerobic biodegradation of a highly toxic compound, the pentachlorophenol (PCP). An enrichment of a microbial consortium, originated from the biomass of an urban wastewater treatment plant, was performed and 70 days were sufficient to achieve removal efficiencies of ∼90% with the compound fed as only carbon and energy source Once completed the start-up period, the SBR was operated with the acclimatized biomass for 60 days at a feed concentration of PCP in the range of 10-20 mg L(-1). Improved performance was observed at increased influent concentration and the reached removal efficiency for the highest concentrations was stable at values≥90%. Kinetic and stoichiometric characterization of the acclimated biomass was performed with biodegradation tests carried out in the bioreactor during the reaction phase. The classical and a modified four-parameter forms of the Haldane equation were applied to model the substrate inhibited kinetics. Both models provided reliable predictions with high correlation coefficients (>0.99). The biomass characterization was completed with the evaluation of the growth yield coefficient, Y (0.075 on chemical oxygen demand base) and endogenous respiration rate, b (0.054 d(-1)). The aerobic SBR, operated in the metabolic mode with a mixed culture, showed superior performance in comparison to continuous systems applied in the same range of PCP influent loads and achieved removal rates are suitable for application.
authors.affiliation: a Water Research Institute, C.N.R ., Via Salaria km 29.300, CP 10 - 00015 Monterotondo Stazione, Rome , Italy.
authors.forename: Domenica Mosca
authors.initials: DM
authors.lastname: Angelucci
authors.forename: M Concetta
authors.initials: MC
authors.lastname: Tomei
mesh_terms: D001420:Bacteria, Aerobic / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D003198:Computer Simulation; D007700:Kinetics; D008657:Metabolic Clearance Rate; D008954:Models, Biological; D010416:Pentachlorophenol / Q000302:isolation & purification* / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification* / Q000378:metabolism*; D018508:Water Purification / Q000379:methods
chemical_list: D014874:Water Pollutants, Chemical; D010416:Pentachlorophenol
keywords: biodegradation; kinetics; pentachlorophenol (PCP); process modelling; sequencing batch reactor (SBR)