落叶松RDH硫酸盐法蒸煮及高白度漂白浆的研究

Conventional and RDH Kraft Pulping of Larch

对比研究了落叶松、南方松ＲＤＨ和常规蒸煮硫酸盐浆。采用氧脱木素及低毒性（ＣＤ）ＥＯ（Ｄｅ）Ｄ漂程，将纸浆漂至８９％（ＩＳＯ）以上，并保持较高的物理强度。ＲＤＨ蒸煮较常规蒸煮可获得卡伯值较低的纸浆，氧脱木素降低了用氯量和漂白废水中ＡＯＸ含量。落叶松浆较南方松浆得率稍低，物理强度性能相近。

Larch from Northeast China and southern pine from the southeastern USA were pulped by conventional and RDH kraft processes and bleached using (CD)(EO)(De)D sequence with 50% chlorine dioxide substitution in the CD stage.The following conclusions are drawn from the results of the study. 1.RDH results lower kappa number,lower viscosity and lower brown stock yield than the conventional kraft process for both species.However,the bleached pulp yields are the same of the two processes. 2.Both the RDH and the conventional pulps from both species are bleached to 89% plus ISO brightness by the bleaching sequence.In spite of the lower viscosity,the strength properties of RDH pulps are better than or at least as good as those of the conventional pulps. 3.Larch pulp yield is 4% lower than southern pine,presumably due to the presence of arabinogalactan in Larch.Aside from the difference in pulp yield,the two species are surprisingly similar in terms of cooking characteristics,bleachability and strength properties of bleached pulp.