title: Value-adding conversion and volume reduction of sewage sludge by anaerobic co-digestion with crude glycerol.
abstract: In this study, conversion of sewage sludge to biogas by anaerobic co-digestion with crude glycerol was examined. When 0.126g/L crude glycerol was added to the reactor, only methane was produced. Upon addition of 5.04g/L crude glycerol, hydrogen production occurred, and a significant amount of 1,3-propanediol (1,3-PDO) was generated in the liquid phase. On day 6, the dry weight was largely composed of organic acids (48%) and 1,3-PDO (17%), which are water-soluble. Degradation of 1,3-PDO was very slow, which is advantageous for recovery. Crude glycerol, which contains alkaline substances, promoted organic matter degradation by microorganisms, which possibly affected biogas and 1,3-PDO production. Addition of 0.630-2.52g/L glycerol initially led to hydrogen production, followed by methane production a few days later, which stabilized within 1week. In conclusion, adjustment of the crude glycerol concentration allows controllable conversion to value-added products for co-digestion.
authors.affiliation: Osaka Prefecture University College of Technology, 26-12 Saiwai-cho, Neyagawa, Osaka 572-8572, Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kurahashi
authors.affiliation: Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Kimura
authors.affiliation: Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
authors.forename: You
authors.initials: Y
authors.lastname: Fujimoto
authors.affiliation: Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan. Electronic address: tokumoto@chemeng.osakafu-u.ac.jp.
authors.forename: Hayato
authors.initials: H
authors.lastname: Tokumoto
mesh_terms: D000693:Anaerobiosis; D056804:Biofuels; D018533:Biomass; D019149:Bioreactors; D005285:Fermentation; D005990:Glycerol / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism; D008697:Methane / Q000096:biosynthesis; D011409:Propylene Glycols / Q000378:metabolism; D012722:Sewage / Q000737:chemistry*; D012995:Solubility
chemical_list: D056804:Biofuels; D011409:Propylene Glycols; D012722:Sewage; C041787:1,3-propanediol; D006859:Hydrogen; D008697:Methane; D005990:Glycerol
keywords: 1,3-Propanediol; Co-digestion; Crude glycerol; Hydrogen; Sewage sludge