[Analysis of dynamic characteristics for fermentative hydrogen-producing bacteria community and hydrogen producing...

The start into the types of fermentation was carried out by pH adjustment from 4.2 to 6.0 in CSTR system. The process of transforming of hydrogen production and dynamic community of bacteria were studied. The results showed that with the organic load maintained at (33 +/- 1) kg/(m3 x d), there was no change in 10 d for the type of fermentation, the amount of hydrogen does not reduce in 8 d. After 15 d, the system was transformed from the ethanol-based type into butyric acid type and water alkalinity was from 250 mg/L to 2450 mg/L. The use of fluorescence in situ hybridization (FISH) system was in response to the 3 groups of micro-organisms. It was found that in the process of transforming, Clostridium cluster XI increases and Clostridium cluster I and II decreases. Enterobacteriaceae always existed with no change. The microbial growth must be considered with hydrogen production capability. The average hydrogen production rate reached to 23.6 mol/(kg x d) with Clostridium cluster I and II dominated in fermentation reactor.