UPGRADING STONE GROUNDWOOD PULP WITH ENERGY SAVING.

The present laboratory study investigates the possibility of improving groundwood pulp quality and/or reducing the energy consumption required for its production. An industrial pulp produced with low specific energy was classified by screen and the fibers of medium length, which have a negative contribution to the pulp strength properties, were refined selectively before being remixed with the rest of the pulp. These modified pulps have more specific surface, longer fiber length, lower sheet density, higher wet-web strength and tear factor, comparable burst factor, and slightly lower breaking length than the corresponding reference pulps. A total energy saving was found possible for some pulps.