本文对杨木硫酸盐浆在高浓条件下电化学介体脱木素的效果进行了研究。实验过程中根据电化学介体脱木素的工艺特点,设计制备了高浓电化学介体脱木素装置,并就该装置的电化学介体脱木素效果及脱木素后浆料的后续可漂性进行了探讨。结果表明:使用设计的电化学介体脱木素装置,能有效地提高电化学介体脱木素的浓度。在紫脲酸浓度2.0mmol/L,温度50℃,电解槽电压2.5V,pH3.0的工艺条件下,浆浓在3%~5%之间,循环流量为0.5L/min,处理时间为8h时,具有较好的脱木素效果。木素脱除率可达到30%左右,经过后续碱处理后,木素脱除率可达到41.4%,黏度降低率仅为10%左右。并且电化学介体脱木素后的纸浆具有较好的过氧化氢后续可漂性,当过氧化氢用量在2.5%时,其白度可达80%ISO以上。
The electrochemical delignification of poplar kraft pulp was investigated. The device of high-consistency electrochemical delignification was designed according to the technology of electrochemical delignification. Technol- ogy conditions of electrochemical delignification were: concentration of violuric acid 2. 0mmol/L, temperature 50~C , voltage 2.5v, pH 3.0. The results showed that using the designed device could efficiently increase the pulp consistency of the electrochemical delignification. The optimum operating parameters of electrochemical delignifica- tion were as follows: pulp consistency between 3% and 5% , electrolyte recycling 0.5L/min and processing time 8h. Under these conditions, the delignification ratio of 30% was obtained which could reach to 41.4% after the following alkali treatment of pulp. The loss of viscosity was about 10%. In addition, the delignified pulp can also be bleached to higher than 80% ISO with following EP stage at 2.5% H202 dosage, which indicates that the pulp has good bleachability.