制浆工艺对高得率KP浆羧基含量的影响

Effect of Process Variables on the Carboxyl Groups Content in Modified High Yield Kraft Pulp

绿液预处理和硫酸盐蒸煮工艺参数影响纸浆的羧基含量。随着绿液用量的增大、预处理温度的升高、时间的延长 ,羧基含量开始增加 ,而后减少 ;当预处理绿液用量为 30 %、 1 2 0℃、处理时间 30～ 40min时 ,羧基含量达到最大值。用碱量是对羧基含量影响最大的参数 ,羧基含量随KP蒸煮段用碱量的增大明显下降 ;H 因子为 1 2 0 0时 ,羧基含量较高。随着卡伯值和得率的降低 ,羧基含量减少。制浆方法也会影响羧基含量 ,不同制浆方法所得的纸浆在得率或卡伯值相同的情况下 ,羧基含量有所不同。

During green liquor pretreatment-kraft pulping process,both pretreatment and kraft cooking variables influence the carboxyl groups content of the pulp.With an increase in green liquor charge,pretreatment temperature and time,the carboxyl content increases at first and then decreases.The carboxyl groups content reaches a maximum when GL/(GL+H 2O)=30%,pretreatment temperature is 120℃,pretreatment time is 30 min.The active alkali dosage of kraft cooking stage influences carboxyl content strongly,the carboxyl groups content of pulps linearly decreases as the active alkali dosage increases.The carboxyl groups content decreases with the decrease of kappa number and unscreened yield of the pulps.