竹化学机械浆筛分耦合长纤维级分磨浆的增强工艺研究

Study on the Enhancement Technology of Bamboo Chemi-mechanical Pulp Classifying Coupled with Long Fiber Fraction Refining

关键词:  竹化机浆  筛分分级  PFI磨浆  耦合增强  纸张性能

Key Words:bamboo chemi-mechanical pulp  classifyng and grading  PFI refining  coupling reinforce  paper properties

摘要:本研究通过筛分竹化学机械浆（简称化机浆）得到各级分原料，耦合长纤维级分进行PFI磨浆处理，并将磨后长纤维级分与未处理短纤维级分按原比例混和抄纸；通过形态、形貌和保水能力确定长纤维分级标准，研究了长纤维级分经PFI磨浆处理后的形态、形貌和滤水性能变化，并分析了竹化机浆筛分耦合长纤维级分磨浆处理对纸张性能的影响。结果表明，竹化机浆中R50和P200/R400级分含量分别为46.4%和27.3%；微观结构表征显示R50和P50/R100级分纤维形态完整，表面较为光滑。筛分耦合长纤维磨浆后，随着PFI磨浆转数增加，R50和R100浆料游离度下降，保水值上升，纤维平均长度减小，平均宽度增加；磨浆转数增至7 500 r时，细小纤维含量分别增至22.3%和26.6%。随磨浆转数的增加，R50和R100纸张松厚度下降，抗张指数和撕裂指数均增加；R50-P50/R400和R100-P100/R400纸张松厚度下降，抗张指数升高，撕裂指数先增加后降低。

Abstract:This study obtained raw materials of various fractions by screening bamboo chemi-mechanical pulp and coupled long fiber fractions for PFI refining treatment. After refining， the long fiber fractions were mixed with untreated short fiber fractions in their original proportions for papermaking. The classification standards for long fiber grading were determined based on morphology， appearance， and water retention capacity. The changes in morphology， appearance， and water filtration performance of long fiber fractions after refining were studied， and the impact of the bamboo chemi-mechanical pulp screening coupled with long fiber fraction refining treatment on paper performance was analyzed. The results showed that the contents of R50 and P200/R400 fraction in bamboo pulp were 46.4% and 27.3%， respectively. The microscopic structures characterization indicated that the fiber morphology of R50 and P50/R100 fraction was incomplete with relatively smooth surfaces. After screening coupled with the refining of long fibers， with the number of PFI refining revolutions increased， the freeness of R50 and R100 pulp decreased， the water retention value increased， the average fiber length decreased， and the average width increased When the refining revolutions increased to 7 500 r， the content of fine fibers increased to 22.3% and 26.6%， respectively. With the increase in refining revolutions， the bulk thickness of R50 and R100 paper decreased， while the tensile index and tear index both increased. For R50-P50/R400 and R100-P100/R400 papers， the bulk thickness decreased， the tensile index increased， and the tear index first increased and then decreased.