IMPROVED DEHYDRATION EFFICIENCY IN PAPER-MAKING SYSTEMS USING MICRO-FIBRILLATED CELLULOSE Russian patent published in 2021 - IPC D21H21/10 D21H17/35 D21H17/36 D21H17/56 D21H17/68 

FIELD: paper industry.

SUBSTANCE: invention relates to producing paper, plates and cardboards. A method includes adding micro-fibrillated cellulose and at least one joint additive to a wet part of a paper-making machine. The joint additive can represent one or more of the following agents: acrylamide-containing cationic water-dispersion polymer, colloidal silicon dioxide, bentonite clay, vinyl amine-containing polymers and their combinations. Micro-fibrillated cellulose is produced from cellulose with a total anionic charge having anionic degree of substitution from 0.02 to 0.50. Vinyl amine-containing polymers are selected from homopolymers of N-vinylformamide, which are completely or partially hydrolyzed to vinyl amine, and which have N-vinylformamide content from 50% to 100% and hydrolysis degree from 30% to 100%. The weight ratio of micro-fibrillated cellulose/joint additive is from 1:10 to 10:1. The amount of micro-fibrillated cellulose and joint additive added to the wet part of the paper-making machine is 0.025-0.5% by weight per weight of dry pulp.

EFFECT: improved efficiency of dehydration in the paper-making machine is provided.

8 cl, 6 tbl, 6 ex