Enzymatic pre-hydrolysis of organic fraction of municipal solid waste to enhance anaerobic digestion

Enzymatic pretreatment was proposed to enhance the anaerobic digestion of Organic Fraction of Municipal Solid Waste (OFMSW). Enzyme cocktails were produced at laboratory scale from Aspergillus niger fermentation on wheat bran (WB) and OFMSW. The effect of enzyme load, reaction time and agitation speed on OFMSW hydrolysis was determined. Results showed that enzymatic hydrolysis of OFMSW improved organic matter solubilisation. Indeed, pretreatment of OFMSW using WB and OFMSW cocktails resulted respectively in 37.1 and 34.6% change of the soluble chemical oxygen demand and 50 and 40.6% change of the reducing sugars. Anaerobic digestion tests showed that enzyme-treated OFMSW yielded higher biomethane production than raw OFMSW. After hydrolysis by WB and OFMSW cocktails, methane potential of OFMSW increased from 189.2 mL gVS?1 to around 607 and 672 mL gVS?1, respectively. The result confirmed that the use of enzyme cocktails derived from raw waste bioconversion could be a valuable approach to improve biomethane potential of organic wastes. - 2019This study was conducted within the framework of MOBIDOC-Post doc as specified in PASRI program (Agence Nationale de Promotion de la Recherche, ANPR). Financial support was provided by the Tunisian Ministry of Higher Education and Scientific Research ( CP-CBS/2015-2019 , Tunisia). Appendix AScopu

Dry mesophilic anaerobic co-digestion of vegetable wastes with animal manures using leach bed reactor

Anaerobic digestion is an environmentally sustainable technology for converting a variety of organic solid feedstocks to energy in the form of methane. To improve methane yield, the digestion of more than one waste is commonly applied. This study aimed to investigate the dry anaerobic co-digestion (TS of 20%) of vegetable wastes (VW) and animal manures (cow manure (CM) and poultry manure (PM)) through conducting biochemical methane potential (BMP) assays at different substrate to inoculum (S/I) ratio. Fractionation and fluorescence analyses showed that organic matter of VW was less accessible and less complex compared to that of CM and PM. The highest methane yields of mono-digestion experiments were registered with S/I 0.5. Best results of methane yield were observed by the co-digestion of VW and CM (284�mL/g VS), which was about 2.3-fold higher than that of VW mono-fermentation. This finding was confirmed at a laboratory-scale leach bed reactor. Result showed an increase of biogas yield from 220 to 445�mL/g VS, during mono and co-digestion, respectively. The co-digestion of VW and CM mixture led to the enhancement of both methane yield and digestate quality in comparison to mono-digestion. 2021, Springer-Verlag GmbH Germany, part of Springer Nature.This research was supported by ERANETMED project (01 DH 17060) BIOGASMENA: Demonstration of biogas technology for rural communities in the Mena region.Scopu