Identifying the Optimal Applications of D and Z for Low Consistency Bleaching of Hard Wood Kraft Pulps, 2002 Fall Technical Conference
New low capital bleaching protocols that allow for optimal use of bleaching chemical remain a high priority for
modern pulp bleaching operations. One attractive approach to this challenge is low consistency D/Z and Z/D
bleaching of kraft pulps. These sequences provide an attractive opportunity for improving the environmental
performance of the bleach plant or increase the capacity of their current bleaching facilities. This paper seeks to
evaluate the bleaching performance of D, Z, D/Z, Z/D, D/Z/D, and Z/D/Z applications for low-consistency
hardwood brownstock and oxygen-delignified pulps. The results from the combined ClO2/O3 stages used in the
present study indicate that the order of chemical addition does not significantly affect the properties of the bleached
pulp. For both brownstock and oxygen-delignified pulps, the D/Z/D sequence showed the highest selectivity while
the D/Z and Z/D stages were equally selective.
Identifying the Optimal Applications of D and Z for Low Consistency Bleaching of Hard Wood Kraft Pul
