Method for removing composite stickers in recycled pulp

Abstract

The invention relates to a sticker-removing method, and provides a method for removing composite stickers in recycled pulp. The provided method can remove stickers efficiently and effectively. The method comprises the following steps: (1) preparing a sticker removing agent; (2) collecting composite stickers in recycled pulp: adding recycled pulp and water into a pulp dispersing machine, dispersing the recycled pulp to form a fiber suspension liquid, and then adding cation polyacrylamide into the suspension liquid to convert the composite stickers in recycled pulp into flocculate; (3) adding the sticker removing agent prepared in the step (1) into the flocculated composite stickers to carry out reactions for 3 to 4 hours, and filtering.

Description

technical field [0001] The invention relates to a method for removing stickies, in particular to a method for removing composite stickies in recycled pulp. Background technique [0002] At present, waste paper has become an important raw material in my country's pulp and paper industry. Recycling waste paper can effectively alleviate the shortage of raw materials in my country and minimize environmental pollution. The most important thing in waste paper recycling is to remove impurities, and the most important impurity is stickies, which has become a major problem that paper mills urgently need to solve. Stickies generally consist of hot melt adhesives, labels, tapes, latex and other polymers found in waste paper. Due to its negative charge in the slurry system, it can adsorb various cationic substances. Stickies are easy to block the equipment such as purifiers and screens during the pulping process; in papermaking, stickies are easy to adhere to felts and drying cylinder...

AI Technical Summary

Problems solved by technology

Stickies are easy to block the equipment such as purifiers and screens during the pulping process; in papermaking, stickies are easy to adhere to felts and drying cylinders, affecting the operation of the paper machine, resulting in paper breakage

[0003] In the prior art, the methods used to remove the adhesives in the recycled pulp generally include physical and chemical agents and biological enzyme methods. The physical methods are usually removed by mechanical operation, and the removal effect of the adhesives is not good, while the chemical methods generally use cations. Type compounds are removed, and the effect is relatively general. It has also been reported that the biological enzyme method has been applied to remove stickies, but the effect is not good.