桉树制浆造纸性能的研究(第二报)——雷州半岛四种桉树浆的漂白试验

<正>对柠檬桉烧碱—蒽醌浆(AP+AQ)和硫酸盐浆(KP)进行了H单段,H—H两段,C—E—H三段以及C—E—H—D四段漂白试验。对雷林一号桉、草律桉、窿缘桉硫酸盐浆还做了H单段漂白性能的对比试验。结果表明:在用氯量7％、浆浓6％,温度40℃、时间3小时的H单段漂白条件下,柠檬桉(AP+AQ)和柠檬桉(KP)的白度均可达70度以上。采用C—E—H—D四段漂,用氯量为6％,柠檬桉(AP+AQ)的白度超过80度,D.P.在800以上。四种桉树中,雷林一号桉的漂白性能最好,窿缘桉最难漂白,草律桉与柠檬桉的漂白性能相近。柠檬桉、草律桉、雷林一号桉制得的漂白浆,物理强度甚好,裂断长6060—8050米,耐折度59—413次,可以用来生产一般文化用纸,也可考虑用来生产某些高级纸张。

STUDIES ON PULPING AND PAPERMAKING PROPERTIES OF EUCALYPTUS WOODSII. Bleaching Experiments on Four Species of Eucalyptus in Leizhou Peninsula

Bleaching experiments on soda-anthraquinone (AP + AQ) and kraft pulps (KP) of E. citriodora have been carried out in the H, H-H, C-E-H, and C-E-H-D sequences. Bleaching properties of kraft pulps of E. Leizhou No.l, E. tsaaulyuh No.2. and E. exserta in the H process have also been tested. Results indicated E. citriodora (AP + AQ) and E. citriodora (KP) both reached a brightness of over 70% (G. E.) , when an active chlorine of 7% and a pulp consistency of 6% were employed under a temperature of 40℃ for three hours in the H sequence. The brightness of E. citriodora (AP +AQ) reached over 80% (G. E.) and D. P. above 800 when chlorine of 7% was used in the C-E-H-D sequence. Of the four species of eucalyptus, the bleaching property of E.Leizhou No.l was the best, and E. exserta was found most difficult to bleach. The bleaching property of E. tsaaulyuh No.2 was similar to that of E. citrodora. Physical strengths of the bleached pulps of E. citriodora, E. tsaaulyuh No.2 and Leizhou No.l turned up to be quite good, with a breaking length of 6060-8050M, and a folding strength of 59-413. All these pulps can be used to produce paper for printing purposes or even some finer paper.