Biorefinery process for extraction, separation, and recovery of fermentable saccharides, other useful compounds, and yield of improved lignocellulosic material from plant biomass

Process of extraction of useful biochemicals from a non-food plant biomass that has hemicellulosic components and a lignocellulosic portion, to yield as a product concentrated, fermentable monomeric and dimeric sugars, the process comprising:

• a) hot-water extraction carried out by contacting a charge of the non-food plant biomass material with water substantially free of reagent, in a pressurized vessel at an elevated temperature up to about 250° C., to yield a mixture of an aqueous extract containing substantially only the hemicellulosic components and other soluble lignocellulosic derived compounds, and the lignocellulosic portion as a separable residue, wherein the lignocellulosic portion is left substantially intact;
• b) separating the lignocellulosic residue and other coarse materials from the aqueous extract;
• c) processing the aqueous extract to remove larger aromatic and oligomeric molecules;
• d) deriving a more pure, concentrated sugar solution from the aqueous extract remaining after step c) by
• sundering of oligomeric sugars in said aqueous extract (d-1) into a concentrated sugar stream and fermentation inhibitory compounds and (d-2) separating the fermentation inhibitory compounds into a permeate stream;
• e) hydrolyzing of the concentrated sugar stream of step d) into monomeric and/or dimeric sugars in an aqueous solution;
• f) prior to any fermentation, removing inhibitory components that result from the hydrolyzing of step e) from the hydrolyzed monomeric and/or dimeric sugar solution of step e) with the separated inhibitory components proceeding as a permeate stream;
• g) concentrating the monomeric/dimeric sugars after step f);
• h) separating the permeate stream after steps d) and f) into individual components;
• and
• i) recovering water from the sugar solution after step f) and from the permeate stream in step h).