HIGH-KAPPA PULPING AND EXTENDED OXYGEN DELIGNIFICATION TO INCREASE YIELD

摘要

The integration of extended oxygen delignification (EOD) into a bleached kraft southern pine mill isrnevaluated. ECF bleaching was used throughout to reach a target brightness of 83-86 % ISO. Comparisonsrnwith conventional kraft and conventional kraft/oxygen flowsheets were made. Production increasernpotential, environmental performance, impact on recovery, pulp strength and production unit costs werernevaluated. The study utilized laboratory pulping, oxygen delignification and DEopD bleaching trials. Thernlaboratory study provided input data for GEMS simulation of the entire pulp mill. On balance, kraftrncooking to kappa 40, followed by (00) DEopD had the greatest productivity increase potential for bothrnrecovery boiler and digester limited mills. However, for a given mill’s product line, the economic optimumrndigester kappa number should be determined prior to the EOD stage(s) in each case.