title: Anaerobic Codigestion of Sludge: Addition of Butcher's Fat Waste as a Cosubstrate for Increasing Biogas Production.
abstract: Fat waste discarded from butcheries was used as a cosubstrate in the anaerobic codigestion of sewage sludge (SS). The process was evaluated under mesophilic and thermophilic conditions. The codigestion was successfully attained despite some inhibitory stages initially present that had their origin in the accumulation of volatile fatty acids (VFA) and adsorption of long-chain fatty acids (LCFA). The addition of a fat waste improved digestion stability and increased biogas yields thanks to the higher organic loading rate (OLR) applied to the reactors. However, thermophilic digestion was characterized by an effluent of poor quality and high VFA content. Results from spectroscopic analysis suggested the adsorption of lipid components onto the anaerobic biomass, thus disturbing the complete degradation of substrate during the treatment. The formation of fatty aggregates in the thermophilic reactor prevented process failure by avoiding the exposure of biomass to the toxic effect of high LCFA concentrations.
authors.affiliation: Chemical and Environmental Bioprocess Engineering Group, Natural Resources Institute (IRENA), University of León, León, León, Spain.
authors.forename: E J
authors.initials: EJ
authors.lastname: Martínez
authors.affiliation: Instituto Nacional del Carbón, INCAR-CSIC, Oviedo, Asturias, Spain.
authors.forename: M V
authors.initials: MV
authors.lastname: Gil
authors.affiliation: Chemical and Environmental Bioprocess Engineering Group, Natural Resources Institute (IRENA), University of León, León, León, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Fernandez
authors.affiliation: Chemical and Environmental Bioprocess Engineering Group, Natural Resources Institute (IRENA), University of León, León, León, Spain.
authors.forename: J G
authors.initials: JG
authors.lastname: Rosas
authors.affiliation: Chemical and Environmental Bioprocess Engineering Group, Natural Resources Institute (IRENA), University of León, León, León, Spain.
authors.forename: X
authors.identifier: http://orcid.org/0000-0001-9595-8825
authors.initials: X
authors.lastname: Gómez
mesh_terms: D000003:Abattoirs; D000693:Anaerobiosis; D000818:Animals; D001673:Biodegradation, Environmental; D056804:Biofuels / Q000032:analysis*; D018533:Biomass; D019149:Bioreactors; D004041:Dietary Fats / Q000032:analysis*; D005232:Fatty Acids, Volatile / Q000032:analysis; D006358:Hot Temperature; D006801:Humans; D008462:Meat-Packing Industry; D008697:Methane / Q000378:metabolism; D012037:Refuse Disposal / Q000379:methods; D012722:Sewage / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014865:Waste Disposal, Fluid / Q000379:methods
chemical_list: D056804:Biofuels; D004041:Dietary Fats; D005232:Fatty Acids, Volatile; D012722:Sewage; D008697:Methane