Patent ID: 8449680

Claim:
A method for treating a cellulosic feedstock, the method comprising: a) subjecting the cellulosic feedstock to impregnation comprising: (i) conveying the cellulosic feedstock having a moisture content through an enclosed volume; (ii) adding moisture to the cellulosic feedstock simultaneously at multiple spaced-apart moisture injection points as the cellulosic feedstock travels through the volume to increase the moisture content of the cellulosic feedstock from 5-15 wt % to 45-55 wt %; (iii) heating the cellulosic feedstock as it travels through the volume to about 50-70° Celsius whereby a heated moistened feedstock that has a relatively uniform temperature and moisture profile is obtained; b) subsequently subjecting the heated moistened feedstock to a downstream hydrolysis process in a steam explosion reactor to obtain an activated feedstock; and, c) subjecting the activated feedstock to an enzymatic hydrolysis process.