Processes for producing biomass pellets and sugars

A process for producing biomass pellets and sugars from cellulosic biomass, said process comprising:

• (a) providing a feedstock comprising cellulosic biomass;
• (b) extracting said feedstock with steam and/or hot water under effective extraction conditions and optionally with an acid catalyst, to produce cellulose-rich solids and an extract liquor containing hemicellulosic oligomers and lignin;
• (c) separating said cellulose-rich solids from said extract liquor;
• (d) filtering said extract liquor to remove at least some of said lignin, thereby generating a filter permeate comprising cleaned extract liquor containing said hemicellulosic oligomers and a filter retentate comprising a lignin-rich stream;
• (e) hydrolyzing said hemicellulosic oligomers in said cleaned extract liquor with an acid or enzymes, to generate hemicellulosic monomers;
• (f) recovering said hemicellulosic monomers;
• (g) recovering acetic acid from said extract liquor and/or from said cleaned extract liquor;
• and
• (h) pelletizing said cellulose-rich solids to form biomass pellets, wherein said pelletizing utilizes at least some of said lignin-rich stream from step (d) as a binder or binder component, and wherein said pelletizing further utilizes at least some of said acetic acid from step (g) as a binder or binder component.