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TAPPI Journal Summaries, Paper360º September/October 2024

Optimizing OCC refining with defloccing, TAPPI Journal April 2025

ABSTRACT: Subjecting pulp to a high shear zone immediately after refining results in more efficient refining. This phenomenon was originally observed to benefit softwood pulp refining. It was attributed to floc reduction based on floc measurements in mill refiners and the observation of reduced headbox plugging. Hence, this phenomenon has been termed “defloccing.” The present work shows this technology also benefits refining of North American old corrugated containers (OCC). The combined results of several mill trials with OCC defloccing demonstrate the interactions between OCC refining intensity, defloccing technology, and other state-of-the-art refining improvements. At the same refining intensity, defloccing OCC on 100% recycled machines increases OCC refining efficiency by 15%, with greater efficiency improvement on machines that use softwood as well as OCC. Furthermore, it is shown that the benefits of defloccing are additive to refining improvements made in the refining zone of a refiner plate. Most OCC refiner plate designs can therefore benefit from the addition of a defloccing feature.

UPM CEO Jussi Pesonen Named European CEO of the Year, Paper360º March/April 2019

UPM CEO Jussi Pesonen Named European CEO of the Year, Paper360º March/April 2019

Pulp Mill Energy Audit Pays Off, Paper360º July/August 2019

Pulp Mill Energy Audit Pays Off, Paper360º July/August 2019

TAPPI Journal Summaries, Paper360º July/August 2019

TAPPI Journal Summaries, Paper360º July/August 2019

TAPPI Journal Summaries, Paper360º March/April 2019

TAPPI Journal Summaries, Paper360º March/April 2019

Facing the Market, Paper360 May/June 2019

Facing the Market, Paper360 May/June 2019

The Shortest Route to Fiber Quality, Paper360 May/June 2019

The Shortest Route to Fiber Quality, Paper360 May/June 2019

Wood Pulp: The New Cotton for the Garment Industry?, Paper360 May/June 2019

Wood Pulp: The New Cotton for the Garment Industry?, Paper360 May/June 2019

Lignin-based resins for kraft paper applications, TAPPI Journal November 2019

ABSTRACT: We investigated miscanthus (MS) and willow (W) lignin-furfural based resins as potential reinforce-ment agents on softwood and hardwood kraft paper. These resins might be sustainable alternatives to the commercial phenolformaldehyde (PF) resins. Phenol is a petrochemical product and formaldehyde has been classified as a carcinogen by the U.S. Environmental Protection Agency. The lignin used in this study was derived from hot water extraction (160ºC, 2 h) of MS and W biomass, and may be considered sulfur-free. These biorefinery lignins were characterized for their chemical composition and inherent properties via wet chemistry and instrumental techniques. The resin blends (MS-resin and W-resin) were characterized for their molecular weight, thermal behavior, and mechanical properties. Mechanical properties were measured by the resin’s ability to reinforce softwood and hard-wood kraft papers. The effect of adding hexamethylenetetramine (HMTA), a curing agent, to the resin was also examined. Mixtures of PF and lignin-based resins were investigated to further explore ways to reduce use of non-renewables, phenol, and carcinogenic formaldehyde. The results show that lignin-based resins have the potential to replace PF resins in kraft paper applications. For softwood paper, the highest strength was achieved using W-resin, without HMTA (2.5 times greater than PF with HMTA). For hardwood paper, MS-resin with HMTA gave the highest strength (2.3 times higher than PF with HMTA). The lignin-based resins, without HMTA, also yielded mechanical properties comparable to PF with HMTA.