TCF Bleaching of Mixed Office Waste, 1994 Pulping Conference Proceedings

P. M. Forsberg, B. Smith, J. M. Genco

A study was conducted on the bleaching of secondary fiber using TCF bleaching sequences. The primary aim of this study was to optimize bleaching conditions in the (EOP) stage to obtain the highest possible brightness for bleaching secondary fiber. Another equally important objective of this study was to bleach to a target brightness of 85%. Using the optimum (EOP) conditions, the sequences studied here were (EOP)ZP, (EOP)ZY, and (EOP)ZFAS. Mixed office waste was used for this experiment. NOW was pulped, deinked, screened, and bleached using a variety of (EOP) stage conditions. Pulp from the three (EO) stages that produced the highest brightness gains were bleached by the sequences (EOP)ZP, (EOP)ZY, and (EOP)ZFAS.

This paper discusses the deinking and bleaching experiment as well as the observed impact of various bleaching conditions on the optical properties. The cost of bleaching is given for the optimum conditions.