Two Stages Oxygen Delignification of Bamboo Kraft Pulp

The factors influencing two-stage oxygen defignification and the comparison of the results of single stage and two-stage oxygen delignification were studied in this experiment.The results indicated that the factors influencing two-stage oxygen delignification were the reaction time,the temperature,the oxygen pressure,the NaOH dosage,and the pulp consistency.When the time was 40min,the temperature was 80℃,the NaOH dosage was 2.0%,the pulp consistency was 10%,the MgSO_4 dosage was 0.5% in the first stage and the time was 60min,the temperature 100℃,the NaOH dosage 0.5%,the pulp consist- ency 10%,the MgSO_4 dosage 0.5% in the second stage,the viscosity of the pulp had little change while the kappa number decreased significantly.The kappa number decreased more in two-stage oxygen delignification than in the single-stage,it was beneficial to the following enzyme treatment and the bleaching with ClO_2 and E_(OP).And also the strength properties of the pulp treated by two-stage oxygen delignification were better than the pulp treated by single-stage deligni- facation.