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Understanding the EUDR: Challenges and Opportunities for the Forest Products Sector, Paper360º September/October 2024

TAPPI News, Paper360º September/October 2024

The Challenges Ahead for the Global Tissue Industry, Tissue360º Spring/Summer 2024

Empowering Sustainable Tissue Production, Tissue360º Spring/Summer 2024

Empowering Sustainable Tissue Production, Tissue360º Spring/

Europap Tezol’s New Vacuum System: Peace of Mind and Major Savings, Tissue360º Spring/Summer 2024

Reducing Water Use in Tissue Making, Tissue360º Spring/Summer 2024

Reducing Water Use in Tissue Making, Tissue360º Spring/Summe

Optimizing Production While Ensuring Product Quality, Tissue360º Spring/Summer 2024

Numerical analysis of the impact of rotor and screen hole plate design on the performance of a vertical pulper, TAPPI Journal April 2025

ABSTRACT: The dissolving of mechanical pulp is one of the most important process steps in stock preparation, since pulping occurs at the very beginning of the papermaking process. Efficient mixing of the pulp in a short amount of time is essential to achieve high furnish volume flow rates. The design of the rotor, as well as the pulper vat and inserts, significantly affects the overall performance of the pulper, such as mixing efficiency and power demand. Using advanced numerical methods such as computational fluid dynamics (CFD) can accelerate the development process. The CFD simulations allow for detailed analysis of flow phenomena, making it possible to study a real-size machine numerically. This approach is particularly advantageous because it can reduce the need for timeconsuming and costly experiments associated with scaling up test rigs. In this study, we compared two different rotor designs utilized in a vertical pulper and evaluated the numerical results with experimental data. Rotor A is designed for low turbulence and low power demand, while rotor B is designed for high turbulence with high power demand. The CFD results showed good agreement with the experimental measurements. We investigated how the rotor design influences the free fluid surface and the mixing efficiency. Our study also highlights the differences in results depending on whether water or furnish is simulated, which exhibit Newtonian or, respectively, non-Newtonian fluid behavior. Additionally, a detailed numerical investigation of various screen hole plate designs revealed that the newly developed hole design significantly reduces pressure loss compared to a standard drilled hole. This outcome was consistent for both types of fluids investigated: water and furnish.

Editorial: PFAS—Intersections with the pulp and paper industry, TAPPI Journal March 2021

ABSTRACT: At the 2019 PEERS Conference in St. Louis, I sat in on a talk concerning the use of fluoropolyomers for welding and reparing of Flexible pipe.

Incorporation of post-consumer pizza boxes in the recovered fiber stream: Impacts of grease on finished product quality, TAPPI Journal March 2021

ABSTRACT: Grease and cheese contamination of used pizza boxes has led to misunderstanding and controversy about the recyclability of pizza boxes. Some collection facilities accept pizza boxes while others do not. The purpose of this study is to determine whether typical grease or cheese contamination levels associated with pizza boxes impact finished product quality. Grease (from vegetable oil) and cheese are essentially hydrophobic and in sufficiently high concentration could interfere with interfiber bonding, resulting in paper strength loss.Findings from this study will be used to determine the viability of recycling pizza boxes at current and future con-centrations in old corrugated containers (OCC) recovered fiber streams. These findings will also be used to inform the acceptability of pizza boxes in the recycle stream and educate consumers about acceptable levels of grease or cheese residue found on these recycled boxes.