US Patent 7608438 Process for the continuous production of ethanol

A process for the production of ethanol utilizes a vacuum process and selectively permeable membranes to increase ethanol production efficiency. Yeast converts sugars to ethanol in an anaerobic condition within process chamber void of oxygen and filled with a Nitrogen gas (N2) or any non-oxygen containing gas. A glucose solution is fed into the process chamber to a yeast solution to ferment. A selectively permeable membrane filters ethanol away from the yeast and out of the process chamber. The removal of ethanol from the process chamber keeps the yeast alive to constantly produce ethanol.