title: Leachate flush strategies for managing volatile fatty acids accumulation in leach-bed reactors.
abstract: In anaerobic leach-bed reactors (LBRs) co-digesting an easily- and a slowly-degradable substrate, the importance of the leachate flush both on extracting volatile fatty acids (VFAs) at the beginning of newly-started batches and on their consumption in mature reactors was tested. Regarding VFA extraction three leachate flush-rate conditions were studied: 0.5, 1 and 2Lkg-1TSd-1. Results showed that increasing the leachate flush-rate during the acidification phase is essential to increase degradation kinetics. After this initial phase, leachate injection is less important and the flush-rate could be reduced. The injection in mature reactors of leachate with an acetic acid concentration of 5 or 10gL-1showed that for an optimized VFA consumption in LBRs, VFAs should be provided straight after the methane production peak in order to profit from a higher methanogenic activity, and every 6-7h to maintain a high biogas production rate.
authors.affiliation: LBE, INRA, 102 avenue des Etangs, 11100 Narbonne, France; Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio, 43, 03043 Cassino (FR), Italy; Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), EA 4508, UPEM, 77454 Marne-la-Vallée, France. Electronic address: silvio.riggio@inra.fr.
authors.forename: S
authors.initials: S
authors.lastname: Riggio
authors.affiliation: LBE, INRA, 102 avenue des Etangs, 11100 Narbonne, France. Electronic address: michel.torrijos@inra.fr.
authors.forename: M
authors.initials: M
authors.lastname: Torrijos
authors.affiliation: Naskeo Environnement, 52 rue Paul Vaillant Couturier, 92240 Malakoff, France. Electronic address: guillaume.vives@naskeo.com.
authors.forename: G
authors.initials: G
authors.lastname: Vives
authors.affiliation: Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio, 43, 03043 Cassino (FR), Italy. Electronic address: giovanni.esposito@unicas.it.
authors.forename: G
authors.initials: G
authors.lastname: Esposito
authors.affiliation: Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), EA 4508, UPEM, 77454 Marne-la-Vallée, France. Electronic address: Eric.vanHullebusch@univ-paris-est.fr.
authors.forename: E D
authors.initials: ED
authors.lastname: van Hullebusch
authors.affiliation: LBE, INRA, 102 avenue des Etangs, 11100 Narbonne, France. Electronic address: jean-philippe.steyer@inra.fr.
authors.forename: J P
authors.initials: JP
authors.lastname: Steyer
authors.affiliation: LBE, INRA, 102 avenue des Etangs, 11100 Narbonne, France. Electronic address: renaud.escudie@inra.fr.
authors.forename: R
authors.initials: R
authors.lastname: Escudié
mesh_terms: D056804:Biofuels / Q000032:analysis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D005232:Fatty Acids, Volatile / Q000032:analysis*; D055442:Metabolome; D008697:Methane / Q000096:biosynthesis; D014835:Volatilization; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D014874:Water Pollutants, Chemical; D008697:Methane
keywords: Dry anaerobic digestion; Leach-bed reactor; Leachate management; VFA consumption; VFA extraction