Process for producing ethanol by fermentation

摘要

Ethanol is prepared from a saccharide such as glucose by a fermentation process. The efficiency of the fermentation is improved by feeding a residual fermented liquid obtained from an evaporator used to vaporize ethanol to a reverse osmosis unit, and then subjecting the residual liquid to reverse osmosis to remove water therefrom. This residual liquid is then recycled to the original fermenter, or to a second fermenter having a smaller volume than the first fermenter.