title: Assessment of methane biodegradation kinetics in two-phase partitioning bioreactors by pulse respirometry.
abstract: Biological methane biodegradation is a promising treatment alternative when the methane produced in waste management facilities cannot be used for energy generation. Two-phase partitioning bioreactors (TPPBs), provided with a non-aqueous phase (NAP) with high affinity for the target pollutant, are particularly suitable for the treatment of poorly water-soluble compounds such as methane. Nevertheless, little is known about the influence of the presence of the NAP on the resulting biodegradation kinetics in TPPBs. In this study, an experimental framework based on the in situ pulse respirometry technique was developed to assess the impact of NAP addition on the methane biodegradation kinetics using Methylosinus sporium as a model methane-degrading microorganism. A comprehensive mass transfer characterization was performed in order to avoid mass transfer limiting scenarios and ensure a correct kinetic parameter characterization. The presence of the NAP mediated significant changes in the apparent kinetic parameters of M. sporium during methane biodegradation, with variations of 60, 120, and 150% in the maximum oxygen uptake rate, half-saturation constant and maximum specific growth rate, respectively, compared with the intrinsic kinetic parameters retrieved from a control without NAP. These significant changes in the kinetic parameters mediated by the NAP must be considered for the design, operation and modeling of TPPBs devoted to air pollution control.
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Spain; Universidad Politécnica de Quintana Roo, Av. Tulum, Manzana 1 Lote 40, SM2, Cancún, Quintana Roo, CP 77500, Mexico.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ordaz
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Spain.
authors.forename: Juan C
authors.initials: JC
authors.lastname: López
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Spain.
authors.forename: Ivonne
authors.initials: I
authors.lastname: Figueroa-González
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Spain.
authors.forename: Raúl
authors.initials: R
authors.lastname: Muñoz
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Spain. Electronic address: gquijano@iq.uva.es.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Quijano
mesh_terms: D000397:Air Pollution / Q000517:prevention & control*; D001673:Biodegradation, Environmental / Q000187:drug effects; D019149:Bioreactors; D007700:Kinetics; D008697:Methane / Q000378:metabolism*; D020581:Methylosinus / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D012827:Silicone Oils / Q000494:pharmacology
chemical_list: D012827:Silicone Oils; D008697:Methane
keywords: Air pollution control; Greenhouse gas; Methane; Pulse respirometry; Two-phase partitioning bioreactors