亚硫酸盐溶解浆漂白工艺的研究

Research on Suli te Dissolving Pulp Bleaching

采用冷碱精制（CCE）与传统CEH漂白相结合的漂白工艺对辐射松亚硫酸盐未漂溶解浆进行漂白,研究了冷碱处理浓度,H段漂白参数对浆料性质的影响,获得了较优的漂白工艺。结果表明：CCE段碱浓为75 g·L^-1;H段用氯量0.5%、漂白p H 9.5~10.0、漂白温度35℃、漂白时间1 h,经处理的浆料特性黏度能达到1010.3 m L·g^-1、白度82.1%ISO、α-纤维素含量92.5%。采用二氧化氯替代氯气时,在其他条件不变的情况下,当二氧化氯用量2.0%、漂白温度70℃、漂白时间3 h,漂后浆料白度能达到87.1%ISO,特性黏度1073.0 m L·g^-1,α-纤维素含量为92.7%,均高于CEH漂白。

In this paper, the traditional CEH bleach process combined with cold caustic extraction （CCE） were employed. Effects of cold caustic concentration and parameters in H bleaching process on the properties of the bleached pulp were studied so as to obtain the optimum bleaching process, The results showed when cold caustic concentration was 75 g·L^-1, chlorine dosage was 0.5%, bleaching pH was 9.5-10.0, bleaching temperature was 35℃, bleaching time 1 hr in H bleaching stage, the bleached pulp viscosity, whiteness, alpha cellulose can reach to 1010.3 mL·g ^-1, 82.1%, 92.53% respectively. When used of chlorine dioxide substitution of chlorine, under the same other conditions, when the amount of chlorine dioxide was 2%, bleaching temperature was 70 centigrade, bleaching time was 3 hr, the bleached pulp viscosity, whiteness, alpha cellulose content can reach to 1073 mL·g ^-1, 87.1% , 92.71% respectively were both higher than CEH bleaching process.