Continuous Biohydrogen Production from Molasses via Dark Fermentation

Dark fermentation is commonly used for producing biohydrogen as a green hydrogen, which can be used as an alternative to fossil fuels. Pilot-scale studies on continuous biohydrogen production from molasses are still limited. In this study, a 60 L pilot-scale up-flow anaerobic sludge bed (UASB) dark fermentation system was operated continuously for biohydrogen production from molasses. The reactor achieved an average hydrogen production rate of 3.64 L H2/L-d. Attention was paid to evaluating total sugar, rather than COD alone, as a more appropriate process indicator for substrate conversion and hydrogen production performance. In addition, metabolic pathway characteristics and microbial community structure were examined. The results provide useful pilot-scale operational data for the implementation of fermentative biohydrogen production technology.