title: Improvement of mesophilic anaerobic co-digestion of agri-food waste by addition of glycerol.
abstract: Anaerobic co-digestion is a promising alternative to manage agri-food waste rather than landfilling, composting or incineration. But improvement of methane yield and biodegradability is often required to optimize its economic viability. Biomethanization of agri-food solid waste presents the disadvantage of a slow hydrolytic phase, which might be enhanced by adding a readily digestible substrate such as glycerol. In this study, strawberry extrudate, fish waste and crude glycerol derived from biodiesel manufacturing are mixed at a proportion of 54:5:41, in VS (VS, total volatile solids), respectively. The mesophilic anaerobic co-digestion at lab-scale of the mixture was stable at loads lower than 1.85 g VS/L, reaching a methane yield coefficient of 308 L CH4/kg VS (0 °C, 1 atm) and a biodegradability of 96.7%, in VS. Moreover, the treatment capacity of strawberry and fish waste was increased 16% at adding the crude glycerol. An economic assessment was also carried out in order to evaluate the applicability of the proposed process. Even in a pessimistic scenario, the net balance was found to be positive. The glycerol adding implied a net saving in a range from 25.5 to 42.1 €/t if compared to landfill disposal.
authors.affiliation: Department of Inorganic Chemistry and Chemical Engineering, University of Cordoba, Campus Universitario de Rabanales, Edificio Marie Curie (C-3), Ctra. N-IV, km 396, 14071 Cordoba, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Serrano
authors.affiliation: Department of Inorganic Chemistry and Chemical Engineering, University of Cordoba, Campus Universitario de Rabanales, Edificio Marie Curie (C-3), Ctra. N-IV, km 396, 14071 Cordoba, Spain.
authors.forename: Jose A
authors.initials: JA
authors.lastname: Siles
authors.affiliation: Department of Inorganic Chemistry and Chemical Engineering, University of Cordoba, Campus Universitario de Rabanales, Edificio Marie Curie (C-3), Ctra. N-IV, km 396, 14071 Cordoba, Spain.
authors.forename: Arturo F
authors.initials: AF
authors.lastname: Chica
authors.affiliation: Department of Inorganic Chemistry and Chemical Engineering, University of Cordoba, Campus Universitario de Rabanales, Edificio Marie Curie (C-3), Ctra. N-IV, km 396, 14071 Cordoba, Spain. Electronic address: iq2masam@uco.es.
authors.forename: M Angeles
authors.initials: MA
authors.lastname: Martin
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D019149:Bioreactors; D005399:Fishes; D005519:Food Preservation; D005525:Food-Processing Industry; D031985:Fragaria; D005990:Glycerol; D007220:Industrial Waste; D008697:Methane / Q000378:metabolism; D018505:Waste Management / Q000379:methods*
chemical_list: D007220:Industrial Waste; D008697:Methane; D005990:Glycerol
keywords: Crude glycerol; Economic assessment; Fish waste; Kinetics; Mesophilic anaerobic co-digestion; Strawberry waste