초록
Batch dark fermentation experiments were performed to investigate the effects of biomass and substrate concentration on bio-hydrogen production from acid hydrolyzed ground wheat at 55 <SUP>o</SUP>C. In the first set of experiments, the substrate concentration was constant at 20 g total sugar L<SUP>-1</SUP> and biomass concentration was varied between 0.52 and 2.58 g L<SUP>-1</SUP>. Total sugar concentration was varied between 4.2 and 23.7 g L<SUP>-1</SUP> in the second set of experiments with a 1.5 g L<SUP>-1</SUP> constant biomass concentration. The highest cumulative hydrogen formation (582 mL, 30 <SUP>o</SUP>C, 1 atm), formation rate (5.43 mL h<SUP>-1</SUP>) and final total volatile fatty acid (TVFA) concentration (6.54 g L<SUP>-1</SUP>) were obtained with 1.32 g L<SUP>-1</SUP> biomass concentration. In variable substrate concentration experiments, the highest cumulative hydrogen (365 mL) and TVFA concentration (4.8 g L<SUP>-1</SUP>) were obtained with 19.25 g L<SUP>-1</SUP> initial total sugar concentration while hydrogen gas formation rate (12.95 mL h<SUP>-1</SUP>) and the yield (200 mL H<SUB>2</SUB> g<SUP>-1</SUP> total sugar) were the highest with 4.2 g L<SUP>-1</SUP> total sugar concentration.