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用2种实验室氧脱木素浆(卡伯值分别为12.0和8.3),研究了二氧化氯(D)和臭氧(Z)在赤桉KP预漂中的联合使用。实验采用Z在(DZ)和(ZD)中按比例取代D(取代量为15%～100%,以等氧化值OXE表示)的方法,评估了预漂白效率。结果发现:采用(DZ)方式要比(ZD)好。对比相应的D0预漂,在40%～50%的取代量下,(DZ)显示了最好的性能,如卡伯值下降、白度提高及黏度的合理下降。与参比流程相比,发现在(DZ)前用热酸处理可使卡伯值降低、总化学品用量减少及白度稳定性提高,而且不会导致强度下降。在D0、DZ和Z预漂浆的最终漂白中,用加压H2O2取代部分ClO2会提高浆的最终白度和减少返黄。
The combined use of chlorine dioxide (D) and ozone (Z) in KP pre-bleaching of Eucalyptus grandis was studied using two laboratory oxygen delignified pulp (Kappa values of 12.0 and 8.3, respectively). In the experiment, the pre-bleaching efficiency was evaluated by a method in which Z was proportionally substituted for D in (DZ) and (ZD) (the substitution amount was 15% to 100%, expressed as the equivalent oxidation number OXE). The results showed that: the use of (DZ) method is better than (ZD). In contrast to the corresponding D0 pre-bleed, (DZ) showed the best performance with a 40% to 50% substitution, such as a decrease in kappa number, an increase in whiteness, and a reasonable drop in viscosity. Compared with the reference process, it was found that treatment with hot acid before (DZ) reduced the Kappa number, reduced total chemical usage and increased whiteness stability without loss of strength. In the final bleaching of D0, DZ and Z pre-bleaching, the replacement of some ClO2 with pressurized H2O2 increases the final whiteness of the pulp and reduces yellowing.