A process for producing a fermentation product from biomass, said process comprising: (a) providing a feedstock containing lignocellulosic biomass and monomeric sugar that is physically bound therein; (b) combining said feedstock with a sugar-fermenting microorganism and optionally cellulase enzymes, to create an initial mixture; (c) refining said initial mixture to mechanically release said monomeric sugar and to intimately mix said sugar-fermenting microorganism and, if present, said cellulase enzymes, wherein the refining employs a refiner selected from the group consisting of a hot-blow refiner, a hot-stock refiner, a blow-line refiner, a disk refiner, a conical refiner, a cylindrical refiner, an in-line defibrator, a homogenizer, and combinations thereof; (d) fermenting said monomeric sugar with said sugar-fermenting microorganism to produce an initial quantity of a fermentation product contained within an intermediate mixture; (e) digesting said intermediate mixture with a solution including steam and/or hot water in a digestor under conditions to produce a digested stream containing cellulose-rich solids, hemicellulose oligomers, and lignin; (f) optionally conveying said digested stream through a mechanical refiner to reduce average particle size of said cellulose-rich solids; (g) optionally separating a vapor from said digested stream and recovering said fermentation product from said vapor; (h) introducing said digested stream to an enzymatic hydrolysis unit under effective hydrolysis conditions to produce cellulosic sugars from said cellulose-rich solids and optionally from said hemicellulose oligomers; and (i) fermenting said cellulosic sugars to produce an additional quantity of said fermentation product; wherein steps (a)-(i), where present, are conducted in order. (a) providing a feedstock containing lignocellulosic biomass and monomeric sugar that is physically bound therein; (b) combining said feedstock with a sugar-fermenting microorganism and optionally cellulase enzymes, to create an initial mixture; (c) refining said initial mixture to mechanically release said monomeric sugar and to intimately mix said sugar-fermenting microorganism and, if present, said cellulase enzymes, wherein the refining employs a refiner selected from the group consisting of a hot-blow refiner, a hot-stock refiner, a blow-line refiner, a disk refiner, a conical refiner, a cylindrical refiner, an in-line defibrator, a homogenizer, and combinations thereof; (d) fermenting said monomeric sugar with said sugar-fermenting microorganism to produce an initial quantity of a fermentation product contained within an intermediate mixture; (e) digesting said intermediate mixture with a solution including steam and/or hot water in a digestor under conditions to produce a digested stream containing cellulose-rich solids, hemicellulose oligomers, and lignin; (f) optionally conveying said digested stream through a mechanical refiner to reduce average particle size of said cellulose-rich solids; (g) optionally separating a vapor from said digested stream and recovering said fermentation product from said vapor; (h) introducing said digested stream to an enzymatic hydrolysis unit under effective hydrolysis conditions to produce cellulosic sugars from said cellulose-rich solids and optionally from said hemicellulose oligomers; and (i) fermenting said cellulosic sugars to produce an additional quantity of said fermentation product;