Various impellers have been used during high-solids loading in stirred tank.
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Various factors affect impeller selection during ethanol fermentation.
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Modifications of existing impellers have great influence on mixing efficiency.
Abstract
An important process in ethanol bioprocesses is the mixing in a bioreactor, which is a general phenomenon. To obtain and maintain mixing efficiency in this process, one of the essential parameters in consideration is the impeller design, which depends on several factors. High sugar titer through enzyme hydrolysis of high-solid biomass has been achieved in recent years. However, there are few literatures on the effect of impeller designs on mixing efficiency of the overall process of enzyme hydrolysis and fermentation, especially simultaneous saccharification and fermentation, and its modifications. This review has provided basic information on the various impeller designs of stirred tank bioreactors and the factors to consider when selecting a suitable impeller for the purpose of increasing ethanol titer from high-solids loading. This shows that an improvement to the impellers can enhance mixing by the modification of existing impellers of stirred tank bioreactors for ethanol production.
