| Abstract:The two-stage oxygen delignification (O1/O2) and four-stage D0EOPD1P bleaching of larch kraft pulp were studied, and the effect of the NaOH charge in O1 stage, ClO2 charge in D0 stage, H2O2 charge in P stage on the bleaching efficiency was discussed，the AOX emissions from bleaching were analyzed. Results indicated that when the dosages of NaOH in O1 stage and in O2 stage, ClO2 in D0 stage, NaOH in EOP stage, ClO2 in D1 stage, and H2O2 in P stage were 2.5%, 0.5%, 2.5%, 2.5%, 0.8% and 2.0% respectively, the brightness of the final bleached pulp was up to 88.4%ISO and pulp viscosity was 701.9 mL/g. The total amount of AOX produced during bleaching was only 0.88 kg/t. |
