纳米TiO_2—两性淀粉对脱墨浆新闻纸抄造过程中DCS去除的研究

Study on the Removal of Dissolved and Colloidal Substances from Deinked Pulp with Nanosized TiO_2

研究了两性淀粉(AmS)、纳米TiO2单元体系、纳米TiO2-AmS双元体系、阳离子淀粉(CS)/阳离子聚丙烯酰胺(CPAM)/阴离子聚丙烯酰胺(APAM)三元体系对全脱墨浆(DIP)的动态絮聚作用,并考察这几种助留助滤体系在白水循环使用情况下,对抄造纸页部分性能及白水中DCS去除效果的影响。动态絮聚实验表明:AmS单元体系几乎没有去除DCS的作用,增大用量还会使体系的DCS残留量更高;纳米TiO2单元体系有一定的DCS去除效果;TiO2-AmS双元体系不仅提高了DCS的去除效果,还降低试剂用量,当其用量为0.16%(TiO2)-0.4%(AmS)时,DCS的去除率达到50%以上;三元体系的助留助滤效果较好,但是DCS的去除效果一般。白水循环使用抄纸实验表明:纳米TiO2-AmS体系对残余油墨的捕集能力最强,对DCS的去除效果也最好,在白水循环抄纸进行到22次时,DCS的富集量达到平衡,白水离心处理后CODCr值为43 mg/L左右,较好抑制了DCS的进一步富集;三元体系在循环进行到52次时,其离心处理后白水CODCr值稳定在65 mg/L左右。

This paper reported the removals of dissolved and colloidal substances （DCS） by flocculating with amphoteric starch （AmS） , nanosized TiO2 , TiO2- AmS dual - system and ternary retention systems contained CS - CPAM - APAM. The experimental results of dynamic flocculation by dynamic drainage jar （DDJ） showed that the AmS alone had little effect on DCS removal; both the nanosized TiO2 alone and the ternary retention system contributed limited effect on DCS removal, and a significant improvement of removal of DCS was achieved by adding TiO2- AmS with the dosage of TiO2（0.16% ） and AmS （0.4%） to the pulp suspension, and the removal ratio of DCS was more than 50%. During the process of hand-sheeting, the TiO2- AmS dual-system contributed to a minimum residual ink eoncentration and maximum brightness. The final equilibrium concentration of DCS for the dual system was lower than that of the ternary-component retention system.