The aim of this work was to investigate anaerobic digestibility of algal bioethanol residue from saccharification and fermentation processes. A series of batch anaerobic digestion tests using saccharification and fermentation residue showed that the maximum methane yields of saccharification residue and fermentation residue were 239. L/kg VS (Volatile Solids) and 283. L/kg VS (Volatile Solids), respectively. Energy recovered by anaerobic digestion of the residue was 2.24 times higher than that from the ethanol produced in the main process. 5-HMF (5-hydroxymethylfurfural), a saccharification byproduct, could retard methanogenesis at over 3. g/L however, the inhibition was prevented by increasing cell biomass concentration. Anaerobic digestion of residue has the potential to enhance bioenergy recovery and environmental sustainability of algal bioethanol production.
Bibliographical noteFunding Information:
This work was supported by a Grant (09-FN-1-0014) from Korea Institute of Energy Technology Evaluation and Planning, Ministry of Knowledge Economy, Republic of Korea and Basic Science Research Program (2011-0014666) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology, Republic of Korea.
All Science Journal Classification (ASJC) codes
- Environmental Engineering
- Renewable Energy, Sustainability and the Environment
- Waste Management and Disposal