US Patent 6896810 Process for producing alkaline treated cellulosic fibers

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.