PULP SOURING PROCESS ENHANCING CONSERVATION OF SPECIFIC BLEACHING AGENT RESIDUALS

摘要

ABSTRACT OF THE DISCLOSUREThere is disclosed a process for souring chemical ormechanical cellulosic pulp using carbon dioxide to obtain properacidification of the pulp slurry. The souring is performed after a single ora multistage bleaching sequence ending with sodium hypochlorite, calciumhypochlorite or hydrogen peroxide or the like in a common process for thepreparation of paper pulp. The use of CO2 permits bleaching to continuebecause CO2 does not destroy the bleaching residuals remaining from thesingle or last bleaching stages.