Johnsonburg Mill Optimizes Chemical Use for Consistent Sheet Brightness

White paper, like white paint, is not just white.

Brightness is an important characteristic in our paper products. The brightness of white paper matters to customers who use it for printing books, brochures or marketing mail.

To achieve the specified brightness, our mills use chlorine dioxide in the pulping process, which is also widely used for treatment of drinking water. We use it to brighten pulp after it’s reduced from wood. The pulp goes through a three-stage bleaching process to achieve the desired brightness before continuing through the mill to become uncoated freesheet paper.

Through a continuous improvement project, the team at our Johnsonburg Mill in Pennsylvania has managed to reduce the volume of chlorine dioxide used while maintaining the brightness our customers expect. The work also highlights Domtar’s commitment to quality and sustainability.

The key to achieving this reduction in chemical use was the installation of an “advanced model predictive control system in the mill’s bleaching plant to reduce variability in the bleaching process,” says John O’Donnell, Domtar’s director of fiber line optimization.

“With this new instrumentation, the team was able to maintain its target brightness, enhance variability metrics and reduce chemical usage, which, in turn, improves the mill’s environmental impact,” he says.
more at: https://newsroom.domtar.com/johnsonburg-sheet-brightness/