IMPROVING PROPERTIES OF POPLAR APMP BY MODIFIED PULPING PROCESS
Changing conventional two stages chemical impregnations into one chemical impregnation before refining and one supplementary bleaching stage after refining in poplar APMP pulping process were studied. Through the comparison of physical properties and beating energy consumption of the pulp obtained from the conventional and the modified APMP pulping process, the optimal conditions of the modified process were: NaOH 4％, H2O2 2％, 50 min, 75℃ and liquor ratio 1: 4 in chemical impregnation stage and NaOH 2％, H2O2 4％, 60 min, 70 ℃ and pulp concentration 10％ in supplementary bleaching stage. 4％ NaOH in the impregnation stage could soften fibers more effectively and 2％ H2O2 could maintain the brightness of pulp and keep off pulp from alkali darkening. 2％ NaOH was sufficient to provide alkali environment for peroxide bleaching, and 4％ H2O2 enabled obtaining high brightness in the supplementary bleaching stage. The brightness of pulp obtained from the modified APMP process increased 4％ ISO. Both the opacity and light scattering coefficient of pulp were improved. The breaking length, tearing index and bursting index of pulp obtained from the modified APMP process increased respectively by 0.5 km, 3％ and 13.3％. The synergy of peroxide with alkali in the modified APMP pulping process not only improved the optical properties of pulps, but also enhanced the strength properties. The supplementary bleaching stage could prevent invalid decomposition of hydrogen peroxide in refining process and pulp yellowing, and promote fiber softening to be beaten and fibrillated more easily, reducing beating energy consumptions. Compared with the conventional process, at the same beating degree as 44 °SR, the beating energy consumption in the modified APMP process was reduced by 17％.
poplar APMP modified APMP pulping supplementary bleaching beating energy saving
Peng Liu Guihua Yang Jiachuan Chen Minmin Yu Kai Zhang
Key Laboratory of Paper Science and Technology of Ministry of Education, Key Laboratory of pulp and paper of Shandong Province, Shandong Polytechnic University, Ji nan, 250353, China
国际会议
16th International Symposium on Wood,Fiber and Pulping Chemistry(第十六届木材、纤维及制浆化学国际会议)
天津
英文
549-552
2011-06-08（万方平台首次上网日期，不代表论文的发表时间）