Improve the deinking of waste printing paper pulp

Japan's Oji Paper Co., Ltd. developed a method that combines neutral flotation and enzyme treatment to deink ink waste printing paper and achieved good results. The waste printing paper stock adds chemicals during the deinking process to enable the agglomerated ink chips to be dispersed to prevent re-deposition on the fibers. A new technology proposed by the company can improve the deinking effect. For example, the neutral flotation method is very effective for deinking waste printing paper. It is generally suitable for lye soaking, but the whiteness of the pulp after deinking The degree is lower than the traditional alkaline flotation method, and the deinking effect on the waste offset paper is poor. Neutral flotation combined with enzyme treatment has the advantages of good deinking effect and high whiteness of pulp. After the waste printing paper pulp is soaked in a lye, a neutral flotation is performed by neutralization and then enzyme treatment, such as using cellulase, xylanase, mannan, amylase and the like. This combination of neutral flotation and enzymatic treatment can remove not only agglomerated ink fragments but also the final whiteness of the deinked pulp 6 to 8 compared to the conventional alkaline flotation deinking method. Degree (ISO).