Patent ID: 7754456

Claim:
A process for producing ethanol from a fibrous lignocellulosic raw material, comprising a) converting the raw material to a solid lignocellulosic fraction with an increased concentration of cellulose and a liquid fraction mainly containing solubilized hemicelluloses; b) hydrolysing the fibrous lignocellulosic material at high consistency with a cellulase enzyme to provide a modified lignocellulosic material with increased flowability; c) simultaneously subjecting the modified lignocellulosic material to continued hydrolysis with a cellulase and to ethanol fermentation in a fermentation mixture; d) continuing fermentation to convert an essential portion of the available carbohydrates into ethanol; e) adding the liquid fraction containing solubilized hemicelluloses to the fermentation mixture and continuing fermentation; and f) recovering ethanol from the fermentation mixture.