title: Simultaneous hydrogen utilization and in situ biogas upgrading in an anaerobic reactor.
abstract: The possibility of converting hydrogen to methane and simultaneous upgrading of biogas was investigated in both batch tests and fully mixed biogas reactor, simultaneously fed with manure and hydrogen. Batch experiments showed that hydrogen could be converted to methane by hydrogenotrophic methanogenesis with conversion of more than 90% of the consumed hydrogen to methane. The hydrogen consumption rates were affected by both P(H₂) (hydrogen partial pressure) and mixing intensity. Inhibition of propionate and butyrate degradation by hydrogen (1 atm) was only observed under high mixing intensity (shaking speed 300 rpm). Continuous addition of hydrogen (flow rate of 28.6 mL/(L/h)) to an anaerobic reactor fed with manure, showed that more than 80% of the hydrogen was utilized. The propionate and butyrate level in the reactor was not significantly affected by the hydrogen addition. The methane production rate of the reactor with H₂ addition was 22% higher, compared to the control reactor only fed with manure. The CO₂ content in the produced biogas was only 15%, while it was 38% in the control reactor. However, the addition of hydrogen resulted in increase of pH (from 8.0 to 8.3) due to the consumption of bicarbonate, which subsequently caused slight inhibition of methanogenesis.
authors: Department of Environmental Engineering, Technical University of Denmark, DK-2800, Kgs Lyngby, Denmark.
authors: Gang
authors: G
authors: Luo
authors: Sara
authors: S
authors: Johansson
authors: Kanokwan
authors: K
authors: Boe
authors: Li
authors: L
authors: Xie
authors: Qi
authors: Q
authors: Zhou
authors: Irini
authors: I
authors: Angelidaki
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000295:instrumentation / Q000379:methods*; D056804:Biofuels; D019149:Bioreactors; D002245:Carbon Dioxide / Q000378:metabolism; D002417:Cattle; D004572:Electrolysis; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005240:Feasibility Studies; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008372:Manure / Q000382:microbiology; D008697:Methane / Q000096:biosynthesis*; D010313:Partial Pressure; D059205:Renewable Energy; D014867:Water / Q000378:metabolism; D014919:Wind
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D008372:Manure; D014867:Water; D002245:Carbon Dioxide; D006859:Hydrogen; D008697:Methane