| 摘要 |
The present invention relates in general to processes for production of ethanol from cellulosic biomass and more in particular to a method for pretreatment of cellulosic biomass feedstock comprising cellulose, hemicellulose, lignin, and sand, the method comprising: contacting in an acid impregnation zone the cellulosic biomass feedstock and an acidic aqueous liquid medium to form an acid-impregnated cellulosic biomass feedstock; removing an aqueous liquid fraction from the acid-impregnated cellulosic biomass feedstock to form an acid-impregnated feedstock having a reduced sabd content and an acidic aqueous liquid fraction comprising sand;removing a sand-rich product from the acidic aqueous liquid fraction; and introducing at least a portion of the acidic aqueous liquid fraction having the sand-rich product removed therefrom into the acid impregnation zone. |
