title: Dynamic modeling of biodegradation and volatilization of hazardous aromatic substances in aerobic bioreactor.
abstract: The aerobic biological process is one of the best technologies available for removing hazardous organic substances from industrial wastewaters. But in the case of volatile organic compounds (benzene, toluene, ethylbenzene, p-xylene, naphthalene), volatilization can contribute significantly to their removal from the liquid phase. One major issue is to predict the competition between volatilization and biodegradation in biological process depending on the target molecule. The aim of this study was to develop an integrated dynamic model to evaluate the influence of operating conditions, kinetic parameters and physical properties of the molecule on the main pathways (biodegradation and volatilization) for the removal of Volatile Organic Compounds (VOC). After a comparison with experimental data, sensitivity studies were carried out in order to optimize the aerated biological process. Acclimatized biomass growth is limited by volatilization, which reduces the bioavailability of the substrate. Moreover, the amount of biodegraded substrate is directly proportional to the amount of active biomass stabilized in the process. Model outputs predict that biodegradation is enhanced at high SRT for molecules with low H and with a high growth rate population. Air flow rate should be optimized to meet the oxygen demand and to minimize VOC stripping. Finally, the feeding strategy was found to be the most influential operating parameter that should be adjusted in order to enhance VOC biodegradation and to limit their volatilization in sequencing batch reactors (SBR).
authors.affiliation: Université de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France.
authors.forename: I
authors.initials: I
authors.lastname: Mozo
authors.forename: G
authors.initials: G
authors.lastname: Lesage
authors.forename: J
authors.initials: J
authors.lastname: Yin
authors.forename: Y
authors.initials: Y
authors.lastname: Bessiere
authors.forename: L
authors.initials: L
authors.lastname: Barna
authors.forename: M
authors.initials: M
authors.lastname: Sperandio
mesh_terms: D001420:Bacteria, Aerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D007700:Kinetics; D008962:Models, Theoretical; D055549:Volatile Organic Compounds / Q000378:metabolism*; D014835:Volatilization; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D055549:Volatile Organic Compounds; D062065:Wastewater; D014874:Water Pollutants, Chemical