Systems and methods by which to subject cellulosic fibers to alkaline treatment
are provided. The systems and methods of the invention include equipment, such
as nanofiltration units and slurry concentrators, which result in a lowered overall
consumption of alkaline solution during alkaline treatment. The systems and methods
of the invention further allow the components of hemicaustic streams produced by
such alkaline treatments to be utilized in higher value end uses.
