Biomethanization of sugar beet byproduct by semi-continuous single digestion and co-digestion with cow manure

• Published in: Bioresource technology Vol. 200; pp. 311 - 319
• Main Authors: Aboudi, Kaoutar, Álvarez-Gallego, Carlos José, Romero-García, Luis Isidoro
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2016
• Subjects: Animals; Beta vulgaris - chemistry; Beta vulgaris - metabolism; Biofuels; Biogas production; Cattle; Co-digestion; Cow manure; Manure; Methane - chemistry; Methane - metabolism; Semi-continuous anaerobic digestion; Sugar beet byproduct; Sugar beet byproduct; Cow manure; Semi-continuous anaerobic digestion; Biogas production; Co-digestion
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2015.10.051

•Individual digestion of sugar beet byproduct is feasible in semi-continuous system.•20-Days hydraulic retention time was the threshold for the single digestion system.•Co-digestion with cow manure allowed to reduce hydraulic retention time to 15-days.•Volatile fatty acids were accumulated during reactors failure.•The source and quality of the inoculum used has permitted to recover the systems. Dried pellet of exhausted sugar beet cossettes were digested alone and combined with cow manure as co-substrate in a mesophilic semi-continuous anaerobic system. In single digestion assay, the stable biogas production and stable reactor operation was observed at the hydraulic retention time (HRT) of 20days (OLR: 3.26gVS/Lreactord) which was the minimum HRT tolerated by the system. However, co-digestion with cow manure allowed to decrease the HRT until 15days (OLR: 4.97gVS/Lreactord) with 32% higher biogas generation and efficient reactor operation. Propionic acid was the predominant VFA observed during single digestion assay failure, while acetic acid accumulation was observed in the co-digestion assay. In both single and co-digestion assays, the recovery of digesters was possible by ceasing the feeding and re-inoculation with a well-adapted inoculum.