title: Biocatalysis conversion of methanol to methane in an upflow anaerobic sludge blanket (UASB) reactor: Long-term performance and inherent deficiencies.
abstract: Long-term performance of methanol biocatalysis conversion in a lab-scale UASB reactor was evaluated. Properties of granules were traced to examine the impact of methanol on granulation. Methanolic wastewater could be stably treated during initial 240d with the highest biogas production rate of 18.6 ± 5.7 L/Ld at OLR 48 g-COD/Ld. However, the reactor subsequently showed severe granule disintegration, inducing granule washout and process upsets. Some steps (e.g. increasing influent Ca(2+) concentration, etc.) were taken to prevent rising dispersion, but no clear improvement was observed. Further characterizations in granules revealed that several biotic/abiotic factors all caused the dispersion: (1) depletion of extracellular polymeric substances (EPS) and imbalance of protein/polysaccharide ratio in EPS; (2) restricted formation of hard core and weak Ca-EPS bridge effect due to insufficient calcium supply; and (3) simplification of species with the methanol acclimation. More efforts are required to solve the technical deficiencies observed in methanolic wastewater treatment.
authors.affiliation: Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8579, Japan.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Lu
authors.affiliation: National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, Ibaraki 305-0053, Japan.
authors.forename: Guangyin
authors.initials: G
authors.lastname: Zhen
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Sendai, Miyagi 980-8579, Japan.
authors.forename: Mo
authors.initials: M
authors.lastname: Chen
authors.affiliation: Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8579, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Kubota
authors.affiliation: Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8579, Japan; Graduate School of Environmental Studies, Tohoku University, Sendai, Miyagi 980-8579, Japan. Electronic address: yyli@epl1.civil.tohoku.ac.jp.
authors.forename: Yu-You
authors.initials: YY
authors.lastname: Li
mesh_terms: D000693:Anaerobiosis; D055162:Biocatalysis; D056804:Biofuels; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D004867:Equipment Design; D008670:Metals / Q000378:metabolism; D008697:Methane / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism*; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods; D062065:Wastewater / Q000737:chemistry
chemical_list: D056804:Biofuels; D008670:Metals; D008697:Methane; D000432:Methanol; D012722:Sewage; D062065:Wastewater
keywords: Extracellular polymeric substances (EPS); Granular sludge; Methane; Methanol; Upflow anaerobic sludge blanket (UASB)