THE EFFECTS ON PULP QUALITY AFTER COOKING AND BLEACHING WHEN BAMBOO IS COOKED TO DIFFERENT KAPPA NUMBERS
Eka Chemicals AB Sweden, South China University of Technology, Guangzhou, China and Karlstad University in Sweden have carried out an extensive evaluation of the optimal way of processing domestic bamboo in the production of high quality bamboo pulps/fibres. The effects of different conditions on the quality of unrefined pulp after both cooking and bleaching processes when cooking to different kappa numbers is discussed first. The unbleached kappa numbers in question ranged from 10 to around 26. Two cooking methods were applied in the laboratory: high temperature with a short cooking time (A pulps) and low temperature with a long cooking time (B pulps). A relevant sample of mill-cooked pulp was used as a reference. Regardless the kappa number, the screened pulp yield of the B pulps was significantly higher than for the A pulps, both before and after bleaching. This can be explained by the increased content of hemicelluloses, particularly xylan. Whatever cooking method is employed, the quality of the pulp is hugely benefited when cooking to kappa numbers above 20: e.g. the tensile index of unrefined pulps was increased from 35 to 45 (Nm/g). The rewetted zero span also increased significantly. Evaluation on the fibre level reveals that these differences are mainly due to increases in deformations (kinks) and dislocations when the pulp is cooked to a very low kappa number. Similar trends, albeit with different absolute values, were observed after ECF (D EOP D) bleaching to 88％ ISO. As far as chemical consumption and environmental impact are concerned, the expected effects of varied kappa number levels were observed: the cooking method had only a minor impact on these parameters.
bamboo non-wood kraft cooking ECF bleaching pulp yield strength properties fibre properties fibre defects fibre strength fibre dislocations
Thomas Greschik Guo Sanchuan Anette Heijnesson-Hult(e)n Jiri Basta Zhan Huaiyu Ulf Germg(a)rd
Eka Chemicals AB, SE-445 80 Bohus, Sweden Karlstad University, SE-651 88 Karlstad, Sweden State Key Laboratory of P&P Engineering, South China University of Technology, Guangzhou, 510640,Chi
国际会议
广州
英文
1461-1464
2010-11-08（万方平台首次上网日期，不代表论文的发表时间）