Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.enconman.2018.04.101
Title (Primary) Year-round biogas production in sugarcane biorefineries: Process stability, optimization and performance of a two-stage reactor system
Author Janke, L.; Weinrich, S.; Leite, A.F.; Sträuber, H.; Radetski, C.M.; Nikolausz, M.; Nelles, M.; Stinner, W.
Journal Energy Conversion and Management
Year 2018
Department UMB
Volume 168
Page From 188
Page To 199
Language englisch
Keywords Sugarcane waste; Anaerobic digestion; Process design; Methane potential; Capacity factor
Abstract The concept of year-round biogas production to increase the capacity factor of anaerobic digestion (AD) plants in sugarcane biorefineries was investigated for the first time in semi-continuous feeding mode. To simulate the use of sugarcane vinasse during the sugarcane season and sugarcane filter cake (SFC) during the off-season period, a two-stage reactor system based on an acidogenic continuous stirred-tank reactor (1st stage) followed by solid–liquid separation and an upflow anaerobic sludge blanket (UASB) reactor (2nd stage) to convert the COD-rich liquid fraction into biogas was operated. Additionally, to optimize the biogas production from SFC, the effects of its thermo-chemical pre-treatment on AD were investigated in a parallel reactor set-up. The saponification effect provided by autoclaving the substrate with sodium hydroxide improved the hydrolysis/fermentation of SFC in the acidogenic reactor, which in turn resulted in a 28% higher volumetric methane production in the methanogenic reactor (p < 0.05). However, the methane yields observed during operation of the two-stage reactor system were markedly lower than previously found in biochemical methane potential tests using SFC. In this case, the feed-in with low suspended solids required by UASB reactors prevented the utilization of the non-hydrolyzed/fermented solid fraction of SFC (> 60% of the substrate’s methane potential). Nevertheless, the capacity factor of the AD plants in sugarcane biorefineries could be increased from 0.55 up to 0.69 when considering a 200 d a−1 sugarcane season (0.66–0.83 for a longer season of 240 d a−1), representing an increase of 25.7%. The average capacity factor for biogas combined heat and power and upgrading units of around 0.91 (8000 h a−1) would be reached if further developments could improve the solubilization of non-hydrolyzed/fermented solids or alternatively allow their direct use in the methanogenic reactor.
Persistent UFZ Identifier
Janke, L., Weinrich, S., Leite, A.F., Sträuber, H., Radetski, C.M., Nikolausz, M., Nelles, M., Stinner, W. (2018):
Year-round biogas production in sugarcane biorefineries: Process stability, optimization and performance of a two-stage reactor system
Energy Conv. Manag. 168 , 188 - 199