(498d) ABE Fermentation In a Continuous and Closed-Circulating Fermentation System with PDMS Membrane Bioreactor

Acetone-Butanol-Ethanol
(ABE) fermentation by combining a PDMS membrane bioreactor and clostridium
acetobutylicum was studied, and thereby a long-term continuous and
closed-circulating fermentation system for ABE production has been achieved.
Two rounds of experiments lasting for 274h and 300h were conducted respectively.
The operation mode of the first round was fermentation intermittently coupling
with pervaporation, and that of the second round was continuously coupling. The
cell concentration, cumulative butanol concentration, butanol volumetric
productivity and glucose consumption rate of the two cycles of fermentation were
1.59 and 1.68 gL^-1, 28.03 and 61.43 gL^-1, 0.11 and 0.21 gL^-1h^-1,
0.63 and 1.12 gL^-1h^-1 respectively. Except for the cell
concentration, the fermentation kinetic parameters of the second cycle were
almost twice those of the first cycle, which indicated the operation mode of
fermentation continuously coupling with pervaporation was superior to that of
intermittently coupling. Besides, at least two peak values were observed in the
profiles of cell growth, glucose consumption and butanol production, which meant
the microorganism revived in the PDMS membrane bioreactor system. The prolonged
fermentation duration and reasonable fermentation kinetics indicated that ABE fermentation
(especially for butanol production) in a continuous and closed-circulating
fermentation system with PDMS membrane bioreactor was feasible and promising.