纤维分级和低浓磨浆后纤维形态如何影响纸的性能

Merging interstage fractionation and low consistency adavantages during the TMP refining process: How fiber morphology impacts paper properties

研究了TMP磨浆工艺中纤维形态及其变化和低浓下进行纤维分级,以便理解纸的性质与磨浆工艺处理之间的相互关系。提出一种广泛深入的分析方法,对物理性能与机械性能进行分析,以表征纤维形态方面的固有性质。本实验磨浆过程主要包括高浓磨浆(HC)的初始阶段、使用小孔径筛框的纤维分级处理阶段、低浓磨浆(LC)阶段、最后的高浓磨浆(HCR)处理阶段。本实验的理念是在后续筛浆阶段浆料已处于低浓度状态。当游离度为100ml CSF时,使用较多的低浓磨浆(LCR)段易于获得较低的抗张强度,但是中试试验值表明其情况稍好。纤维分级实验表明,可以通过使用LCR来维持纤维的长度和改善长纤维结合情况;研究同时表明,在保证纤维强度不变的情况下,也可以减少能耗。从本实验的研究看出,大量的纤维结合和纤维结合密度的增加,可在很大程度上改善已发生内部脱层作用的纤维结构。

Fiber morphology and its evolution during refining and fraction at low consistency were studied to understand the key relationships between the mechanical properties of paper and those of fibers. A broad analysis is presented on the physical and mechanical properties characterising the intrinsic morphological properties of fibers. The experimental refining process involved a primary stage at high consistency （HC）, a fractionation stage with a small aperture basket, a low consistency （LC） refining stage, and a final high consistency refining （HCR） stage. The idea was to benefit from the pulp already being at low consistency following the screening step. Using a higher proportion of low consistency refining （LCR） tended to lower the tensile strength at 100 ml CSF, but some intermediate values did exhibit better responses to refining. Fractionation permits the use of LCR to retain fiber length and to develop additional long fiber bonding. The net gain remains even with energy reduction. It is believed, among other things, that a greater number or greater intensity of fiber-to-bar contacts would help increase internal delamination of the fiber structure.