Fluidized-Bed Bioreactors Using a Flocculating Strain of Zymomonas Mobilis for High-Productivity Ethanol Fermentation

摘要

The flocculating strain of Zymomonas mobilis (NRRL B-12526) has been shown to form stable floc particles that can effectively convert glucose to ethanol at rates in excess of 400 g/L.h in a fluidized-bed bioreactor. The system is so reactive that the CO sub 2 off-gas makes it difficult to maintain high biomass loading in the upper part of the reactor, thus, resulting in a reduced ethanol productivity that approaches 100 g/L.h for the entire active reactor volume when over 95% of the glucose is metabolized. An increase in biomass loading and the use of a glucose feed concentration in excess of 150 g/L will undoubtedly result in even high levels of ethanol productivity. 12 references, 6 figures, 2 tables. (ERA citation 08:055573)