title: Dynamic biogas upgrading based on the Sabatier process: thermodynamic and dynamic process simulation.
abstract: This study aimed to investigate the feasibility of substitute natural gas (SNG) generation using biogas from anaerobic digestion and hydrogen from renewable energy systems. Using thermodynamic equilibrium analysis, kinetic reactor modeling and transient simulation, an integrated approach for the operation of a biogas-based Sabatier process was put forward, which was then verified using a lab scale heterogenous methanation reactor. The process simulation using a kinetic reactor model demonstrated the feasibility of the production of SNG at gas grid standards using a single reactor setup. The Wobbe index, CO2 content and calorific value were found to be controllable by the H2/CO2 ratio fed the methanation reactor. An optimal H2/CO2 ratio of 3.45-3.7 was seen to result in a product gas with high calorific value and Wobbe index. The dynamic reactor simulation verified that the process start-up was feasible within several minutes to facilitate surplus electricity use from renewable energy systems.
authors.affiliation: Aalborg University Esbjerg, Niels Bohrsvej 8, 6700 Esbjerg, Denmark; Flensburg University of Applied Sciences, Kanzleistr. 91, 24937 Flensburg, Germany. Electronic address: lars.juergensen@fh-flensburg.de.
authors.forename: Lars
authors.initials: L
authors.lastname: Jürgensen
authors.affiliation: Flemish Institute of Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium.
authors.forename: Ehiaze Augustine
authors.initials: EA
authors.lastname: Ehimen
authors.affiliation: Flensburg University of Applied Sciences, Kanzleistr. 91, 24937 Flensburg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Born
authors.affiliation: Aalborg University Esbjerg, Niels Bohrsvej 8, 6700 Esbjerg, Denmark.
authors.forename: Jens Bo
authors.initials: JB
authors.lastname: Holm-Nielsen
mesh_terms: D056804:Biofuels; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000032:analysis; D002245:Carbon Dioxide / Q000032:analysis; D003198:Computer Simulation; D007700:Kinetics; D008697:Methane / Q000032:analysis; D011312:Pressure; D015203:Reproducibility of Results; D013816:Thermodynamics
chemical_list: D056804:Biofuels; D002245:Carbon Dioxide; D002244:Carbon; D008697:Methane
keywords: Anaerobic digestion; Biogas; Methanation; Sabatier reaction; Upgrading