Stable operation during pilot-scale anaerobic digestion of nutrient-supplemented maize/sugar beet silage
2012 (English)In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 118, 445-454 p.Article in journal (Refereed) Published
Biogas production from maize/sugar beet silage was studied under mesophilic conditions in a continuous stirred tank reactor pilot-scale process. While energy crop mono-digestion is often performed with very long hydraulic retention times (HRTs), the present study demonstrated an efficient process operating with a 50-day HRT and a corrected total solids (TScorr) based organic loading rate of 3.4 kg/m3×d. The good performance was attributed to supplementation with both macro- and micronutrients and was evidenced by good methane yields (318 m3/ton TScorr) which were comparable to laboratory maximum expected yields plus low total volatile fatty acid concentrations (< 0.8 g/L). A viscoplastic and thixotropic digester fluid behaviour was observed, and the viscosity problems common in crop mono-digestion were not seen in this study. The effluent also complied with Swedish certification standards for bio-fertilizer for farmland application. Nutrient addition thus rendered a stable biogas process, while the effluent was a good quality bio-fertilizer.
Place, publisher, year, edition, pages
Elsevier, 2012. Vol. 118, 445-454 p.
Bio-fertilizer, Biogas, Energy crops, Macronutrients, Micronutrients
IdentifiersURN: urn:nbn:se:liu:diva-81648DOI: 10.1016/j.biortech.2012.05.096ISI: 000307259600060OAI: oai:DiVA.org:liu-81648DiVA: diva2:555439