THE EFFECTS OF WATER CIRCUIT CLOSURE IN A PULP-MILL

Environmental pressures and recent advances in low-kappa cooking and TCF bleaching have further stimulated interest in minimizing the environmental impacts of kraft mills. Bleaching without chlorine-containing chemicals offers new ways to integrate bleach plant waste waters in the kraft recovery system and to close the water circuit. This article describes the scope for minimizing water usage in a Z-EOP-ZP bleach plant, the characteristics and compositions of waste streams as well as ways of combining them in the mill water system.