title: Anaerobic co-digestion of acetate-rich with lignin-rich wastewater and the effect of hydrotalcite addition.
abstract: The methane potential and biodegradability of different ratios of acetate and lignin-rich effluents from a neutral sulfite semi-chemical (NSSC) pulp mill were investigated. Results showed ultimate methane yields up to 333±5mLCH4/gCOD when only acetate-rich substrate was added and subsequently lower methane potentials of 192±4mLCH4/gCOD when the lignin fraction was increased. The presence of lignin showed a linear decay in methane production, resulting in a 41% decrease in methane when the lignin-rich feed had a 30% increase. A negative linear correlation between lignin content and biodegradability was also observed. Furthermore, the effect of hydrotalcite (HT) addition was evaluated and showed increase in methane potential of up to 8%, a faster production rate and higher soluble lignin removal (7-12% higher). Chemical oxygen demand (COD) removal efficiencies between 64 and 83% were obtained for all samples.
authors.affiliation: Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland; Institute of Energy Technologies, Technical University of Catalonia, Barcelona, Spain. Electronic address: lourdes.rodriguezchiang@aalto.fi.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Rodriguez-Chiang
authors.affiliation: Institute of Energy Technologies, Technical University of Catalonia, Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Llorca
authors.affiliation: Department of Forest Products Technology, School of Chemical Technology, Aalto University, P.O. Box 16300, Vuorimiehentie 1, Espoo, Finland.
authors.forename: Olli
authors.initials: O
authors.lastname: Dahl
mesh_terms: D000085:Acetates / Q000737:chemistry / Q000378:metabolism*; D000536:Aluminum Hydroxide / Q000737:chemistry; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D005387:Finland; D008031:Lignin / Q000737:chemistry / Q000378:metabolism; D008276:Magnesium Hydroxide / Q000737:chemistry; D008697:Methane / Q000096:biosynthesis*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D000085:Acetates; D000536:Aluminum Hydroxide; D008031:Lignin; D008276:Magnesium Hydroxide; D008697:Methane; D062065:Wastewater; C010467:hydrotalcite
keywords: Co-digestion; Evaporator condensate; Hydrotalcite; Lignin; Methane potential