title: Improved Monitoring of Semi-Continuous Anaerobic Digestion of Sugarcane Waste: Effects of Increasing Organic Loading Rate on Methanogenic Community Dynamics.
abstract: The anaerobic digestion of filter cake and its co-digestion with bagasse, and the effect of gradual increase of the organic loading rate (OLR) from start-up to overload were investigated. Understanding the influence of environmental and technical parameters on the development of particular methanogenic pathway in the biogas process was an important aim for the prediction and prevention of process failure. The rapid accumulation of volatile organic acids at high OLR of 3.0 to 4.0 gvs·L⁻¹·day⁻¹ indicated strong process inhibition. Methanogenic community dynamics of the reactors was monitored by stable isotope composition of biogas and molecular biological analysis. A potential shift toward the aceticlastic methanogenesis was observed along with the OLR increase under stable reactor operating conditions. Reactor overloading and process failure were indicated by the tendency to return to a predominance of hydrogenotrophic methanogenesis with rising abundances of the orders Methanobacteriales and Methanomicrobiales and drop of the genus Methanosarcina abundance.
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15, 04318 Leipzig, Germany. athaydes.leite@ufz.de.
authors.forename: Athaydes Francisco
authors.initials: AF
authors.lastname: Leite
authors.affiliation: Department of Biochemical Conversion, Deutsches Biomasseforschungszentrum Gemeinnützige GmbH, Torgauerstrasse 116, 04347 Leipzig, Germany. leandro.janke@dbfz.de.
authors.forename: Leandro
authors.initials: L
authors.lastname: Janke
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15, 04318 Leipzig, Germany. zuopeng.lv@ufz.de.
authors.forename: Zuopeng
authors.initials: Z
authors.lastname: Lv
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15, 04318 Leipzig, Germany. hauke.harms@ufz.de.
authors.forename: Hauke
authors.initials: H
authors.lastname: Harms
authors.affiliation: Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15, 04318 Leipzig, Germany. hans.richnow@ufz.de.
authors.forename: Hans-Hermann
authors.initials: HH
authors.lastname: Richnow
authors.affiliation: Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15, 04318 Leipzig, Germany. marcell.nikolausz@ufz.de.
authors.forename: Marcell
authors.initials: M
authors.lastname: Nikolausz
mesh_terms: D000693:Anaerobiosis; D019149:Bioreactors; D017012:Methanobacteriales / Q000378:metabolism; D017020:Methanosarcina / Q000378:metabolism; D012037:Refuse Disposal / Q000379:methods*; D031786:Saccharum; D014866:Waste Products
chemical_list: D014866:Waste Products
keywords: biogas reactor overloading; methanogenic pathways; monitoring tool; stable isotope fingerprinting; sugarcane waste