硫酸盐蔗渣浆全无氯短序漂白生产工艺的研究

Study on the Chlorine-free Short Sequence Bleaching Process of Kraft Bagasse Pulp

在尽可能模仿工厂实际生产条件下,采用酸处理-臭氧-过氧化氢(AZP)全无氯(TCF)短序清洁漂白生产流程对硫酸盐蔗渣浆漂白工艺参数进行研究。实验结果表明,硫酸盐蔗渣浆漂白最佳工艺条件为:Z段浆浓36%,pH值2.0,臭氧用量1.2%,臭氧浓度120 g/m3,反应时间30 min,室温下进行;P段浆浓10%,过氧化氢用量3.0%,反应时间120 min,反应温度90℃,NaOH用量0.8%。最终得到的漂白硫酸盐蔗渣浆白度85.6%、黏度559 mL/g以及卡伯值3.6。同时,与传统漂白工艺流程(OQP1P2、OP1ZP2)相比,采用AZP短序漂后废水污染负荷最低,漂后废水CODCr为760 mg/L、BOD5为90 mg/L以及色度为680 C.U.。

With the conditions closely imitating the practice production of the mill,the parameters of sulfate bagasse pulp acid pretreatmentozone-hydrogen peroxide(AZP)short sequence total chlorine free(TCF)bleaching process were studied.The experimental results showed that the optimum process conditions were:pulp consistency 36%,pH value 2.0,ozone dosage 1.2%,ozone concentration 120 g/m3,reaction time 30 min,at room temperature for Z-stage;for P-stage pulp consistency 10%,the peroxidation dosage 3%,reaction time 120 min,reaction temperature 90℃,NaOH dosage 0.8%.The whiteness,viscosity and Kappa number of the bleached kraft bagasse pulp were 85.6%,559 mL/g and 3.57,respectively.At the same time,compared with the traditional bleaching processes(OQP1P2,OP1ZP2),the pollution load was the lowest when AZP short sequence bleaching was applied,CODCrvalue was 760 mg/L,BOD5 was 90 mg/L,and chroma value was 680 C.U.