NOVELTY - A process for converting lignocellulosic biomass to ethanol comprising, feeding a moist lignocellulosic biomass feedstock into a dilute acid impregnator, dewatering the acid-soaked biomass and hydrolyzing the biomass to convert the soluble oligosaccharides to monomeric sugars.    USE - Used to obtain fermentable sugars from lignocellulosic which are used to produce ethanol.    ADVANTAGE - The yield of ethanol is increased without the need for detoxification of the hydrolyzate, the nutrient requirements are reduced and the second stage slurry fermentation eliminates the need for washing the second stage hydrolyzate to recover the sugars.    DETAILED DESCRIPTION - A process for converting lignocellulosic biomass to ethanol, the improvement of obtaining higher fermentable soluble sugar yields by drying acid impregnated biomass particles comprising:    (a) feeding a moist lignocellulosic biomass feedstock into a dilute acid impregnator for sufficient residence time to render it acid soaked and draining the acid-soaked biomass to 30-35% by weight solids;    (b) dewatering the acid-soaked biomass by drying or centrifugation in a manner to prevent densifying the biomass particles and obtain a solids content of 40-60% wet weight basis;    (c) subjecting the acid-impregnated biomass to a first-stage hydrolysis reactor and discharging the formed hydrolyzate into a first flash tank to hydrolyze most of the soluble oligosaccharides to monomeric sugars and flashing the remaining hydrolyzate to a second flash tank at a lower temperature than the first, the second tank serves as a feed surge tank for a counter-current extractor;    (d) washing the hydrolyzate, recovering more than about 95% of the soluble sugars in the first stage hydrolyzate slurry by a counter-current extractor, and adjusting the pH to about 5;    (e) subjecting the remaining washed first stage pretreated solids to a second stage acid and metal salt impregnator and de-watering by drying or centrifugation in a manner so as to prevent compaction of the biomass particles and obtain a solids content of 40-60 wt.% wet;    (f) subjecting the acid and metal salt-impregnated biomass to a second-stage hydrolysis reactor at a temperature of 190-240degreesC and discharging the formed hydrolyzate into a flash tank at 120-140degreesC to hydrolyze most of the remaining soluble oligosaccharides to monomeric sugars and flashing the remaining to a second flash tank at a lower temperature than the first, the second flash tank serving as a feed surge tank for second-stage fermentors;    (g) cooling the pH-adjusted extract from the counter-current extractor, feeding the extract to a first stage fermentor at a rate to promote enough yeast growth to compensate for loss through second-stage fermentors;    (h) pH adjusting second-stage hydrolyzate slurry to about 4.5, cooling the slurry and adding it into the top of the first fermentor of the second-stage fermentation train, pumping broth from the bottom of the first fermentor to the top of a second fermentor so the carried over yeast consumes 95% of the fermentable sugars; and    (i) recovering the ethanol.