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研究了蓝桉硫酸盐法制浆过程中提高原料中聚糖留着率的方法。添加蒽醌(AQ)的硫酸盐法制浆得率最高;添加尿素能减少聚糖的解聚(浆料黏度增加),但对浆料得率无显著影响。在硫酸盐法蒸煮过程中,提早中断蒸煮,尤其是在快速、有选择性的大量脱木素段后便停止蒸煮,然后再进行氧脱木素是提高纸浆得率的有效方法。氧脱木素的得率损失明显低于硫酸盐法蒸煮过程终段(残余脱木素阶段)所造成的得率损失。在蒸煮的3个阶段,控制蒸煮液中OH?/HS?的用量也能提高纸浆得率,但纸浆得率随总用碱量减少而增加的结论是相比常规制浆条件下得到的。在常规硫酸盐法制浆中,活性碱用量对纸浆得率和黏度起决定性作用。低活性碱用量(14%)在提高纸浆得率的同时能保持纸浆黏度基本不变或略有上升,纸浆得率提高分别为纤维素和木素保留量提高所致。在制浆终段,纤维素组分的降低是纸浆得率下降的主要原因,而木聚糖组分基本保持不变,这是蓝桉半纤维素结构的特殊性所致。
The method of increasing the retention of polysaccharides in raw materials during the process of cyanobacteria kraft pulping was studied. Kraft pulping with the addition of anthraquinone (AQ) yielded the highest yield; addition of urea reduced the disaggregation of polysaccharides (increased slurry viscosity) but did not have a significant effect on the yield of the slurry. During kraft cooking, early interruption of cooking, especially after a fast, selective, large delignification stage, and then oxygen delignification is an effective method to increase pulp yield. The yield loss of oxygen delignification was significantly lower than the loss of yield due to the end of the kraft cooking process (residual delignification stage). In the three stages of cooking, the dosage of OH? / HS? In the cooking liquor can also increase the yield of pulp, but the conclusion that the yield of pulp increases with the decrease of the total amount of alkali is obtained under the conditions of conventional pulping. In conventional kraft pulping, the amount of active base has a decisive effect on pulp yield and viscosity. Low active alkali dosage (14%) can keep the pulp viscosity almost unchanged or slightly while increasing the yield of pulp. The increase of pulp yield is caused by the increase of cellulose and lignin retention. In the final stage of pulping, the decrease of cellulose component is the main reason for the decline of pulp yield, while the xylan component remains basically unchanged, which is caused by the special structure of hemicellulose.