Enhancing the hydrolysis process in a dry anaerobic digestion process for the organic fraction of municipal solid waste. (September 2020)

• Record Type: Journal Article
• Authors: Nasir, Zeeshan; Ahring, Birgitte K.; Uellendahl, Hinrich
• Is Part Of: Bioresource technology reports. Volume 11(2020)
• Publication Date: 2020-09
• Subjects: Organic fraction of municipal solid waste -- Single and multistage anaerobic digestion -- Recirculation -- Waste/percolate ratio -- Enzymatic hydrolysis; Biomass energy -- Periodicals; Biotransformation (Metabolism) -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Waste products as fuel -- Periodicals; Waste products as fuel; Organic wastes; Factory and trade waste; Biotransformation (Metabolism); Biomass energy; Agricultural wastes; Periodicals; Electronic journals; 662.88
• DOI: 10.1016/j.biteb.2020.100542
• Languages: English
• ISSNs: 2589-014X

Abstract

Abstract: The potential of leachate recirculation and enzyme addition for increasing the conversion efficiency of a 2-stage dry anaerobic digestion process of OFMSW was studied and compared to a 1-stage setup. In the 2-stage reactor setup the methane yield increased from 31 to 227 ml-CH4/g-VS by lowering waste/percolate ratio from 6.5 to 2 (based on VS). Eventual pH increase and lower VFA release in the leachate indicated that methanogenesis occurred also in the first stage of the 2-stage system. The high waste/percolate ratio of 6.5 lead to overload of both 1- and 2-stage processes while lowering the waste/percolate ratio to 4 resulted in a methane yield of 268 ml-CH4/g-VS in the 1-stage reactor system. The higher water saturation of the waste led obviously to more homogenous process conditions. Addition of two different enzyme blends with cellulase and hemicellulase activity resulted in 19% increase of the methane potential. Graphical abstract: Unlabelled Image Highlights: Stable conversion of OFMSW to methane at waste/percolate ratio of 4 and 2 in 1- and 2-stage AD systems VFA overload at a waste/percolate ratio of 6.5 in both 1-stage and 2-stage AD systems 19% increase in theoretical methane potential realization with external cellulolytic enzymes