Effects on Retention and Drainage of Converting from 100% OCC to 50% OCC: 50% NSSC in a Closed-Cycle Paperboard Mill, 2001 Papermakers Conference Proceedings
The Smurfit-Stone mill at Matane, Québec, recently converted its furnish from 100% old corrugated containers (OCC) to 50% OCC:50% neutral sulphite semi-chemical (NSSC) pulp. The work reported here was to determine the best retention and drainage aid for the new furnish. Results indicated that the poly(ethylene oxide) (PEO)/cofactor retention aid systems were the most efficient in first-pass retention, vacuum drainage, and free drainage. PEO, a neutral polymer, works well in the presence of large amounts of anionic trash in NSSC pulp. However, PEO systems retain more water in the sheet than other retention aids, forming a wetter sheet. We found that the polymer chitosan performed well in a highly anionic NSSC environment. It was one of several other systems that we investigated. Final sheet properties in this study were the result of the furnish composition and the retention aid system used.
Effects on Retention and Drainage of Converting from 100% OCC to 50% OCC: 50% NSSC in a Closed-Cycle