title: Effects of mechanical treatment of digestate after anaerobic digestion on the degree of degradation.
abstract: The aim of this study was to increase the biogas production from different substrates by applying a mechanical treatment only to the non-degraded digestate after the fermentation process in order to feed it back into the process. To evaluate this approach, digestates were grounded with a ball mill for four different treatment time periods (0, 2, 5, 10 min) and then the effects on the particle size, volatile organic substances, methane yield and degradation kinetic were measured. A decrease of volatile fatty acids based on this treatment was not detected. The mechanical treatment caused in maximum to a triplication of the methane yield and to a quadruplicating of the daily methane production.
authors.affiliation: University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany. Electronic address: Jonas.Lindner@uni-hohenheim.de.
authors.forename: Jonas
authors.initials: J
authors.lastname: Lindner
authors.affiliation: University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Zielonka
authors.affiliation: University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Oechsner
authors.affiliation: University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Lemmer
mesh_terms: D000693:Anaerobiosis; D056804:Biofuels; D019149:Bioreactors / Q000382:microbiology; D005232:Fatty Acids, Volatile / Q000032:analysis; D007700:Kinetics; D008697:Methane / Q000096:biosynthesis; D010316:Particle Size; D012037:Refuse Disposal / Q000379:methods*; D013314:Stress, Mechanical; D013997:Time Factors; D014835:Volatilization
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D008697:Methane
keywords: Anaerobic digestion; Digestate; Lignocellulose; Mechanical treatment; Methane yield