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Journal articles
Magazine articles
Numerical analysis of slot die coating of nanocellulosic materials, TAPPI Journal November 2020
ABSTRACT: Nanocellulosic coatings as a food packaging material are of commercial interest due to their nontoxic nature, renewability, and excellent barrier properties. Complex shear-thinning rheology poses challenges in designing and sizing equipment to pump, mix, and process the suspension and actual coating process. This study aims to determine the effectiveness of computational fluid dynamics (CFD) in predicting nanocellulosic suspension flow in light of existing rheological data. We employ and compare three distinct rheological models to characterize the rheology and flow of nanocellulose suspensions through a slot die coater, where the model parame-ters are established from existing slot rheometry measurements. A volume-of-fluid (VoF) based finite volume meth-od is employed to simulate the flow in a slot die operated in an unconventional metering mode. Results with the Casson model predict the presence of unyielded regions in the flow, which was not captured using the power law model. These stagnation regions will incur coatability issues stemming from flow intermittencies and lead to poten-tial defects in the coating layer, including fracture. The results suggest that a rheological model that includes yield stress should be considered while modeling such flows. A need for better rheological data to model nanocellulosic flows, especially at high consistencies and shear rates, is also highlighted.
Journal articles
Magazine articles
The use of hollow sphere pigments as strength additives in paper and paperboard coatings—Part 2: Optimization in paperboard formulations for opacity and strength, TAPPI Journal November 2020
ABSTRACT: This report aims to summarize the efforts in testing the properties of coatings for paperboard utilizing hollow sphere pigments (HSPs). HSPs are known to effectively scatter light and replace titanium dioxide (TiO2) in architectural coating formulations. The effect of the particle size and void fraction was evaluated, along with many coating parameters, including level of addition, binder chemistry, and blends of two HSPs. The small HSPs that have optimized voids for scattering light showed equivalent strength to the TiO2-containing control. The strength data was surprising, particularly the improvement in strength for coatings containing large particle size HSPs. Because of this increase in strength, four parts of binder could be removed, which allowed for higher brightness while not compromising other properties, including hot melt glueability. These trends held true using different binder chemistries (styrene acrylic, vinyl acrylic, and styrene butadiene). Upon refining the formulations further, blends of two HSPs showed further benefit.
Conference papers
New Revenue Opportunities for Pulp and Paper Sector from Carbon Capture, 20PEERS Conference
New Revenue Opportunities for Pulp and Paper Sector from Carbon Capture, 20PEERS Conference
Conference papers
FEL1 and 2 • The Beginnings of Successful Paper Machine Conversions, 20PEERS Conference
FEL1 and 2 • The Beginnings of Successful Paper Machine Conversions, 20PEERS Conference
Conference papers
CROSS FLOW FILTRATION OF GREEN LIQUOR FOR INCREASED PULP PRODUCTION, IMPROVED GREEN LIQUOR QUALITY, AND ENERGY SAVINGS, 20PEERS Conference
CROSS FLOW FILTRATION OF GREEN LIQUOR FOR INCREASED PULP PRODUCTION, IMPROVED GREEN LIQUOR QUALITY, AND ENERGY SAVINGS, 20PEERS Conference
Conference papers
The Usefulness of Two-Side ERIC Buchner Handsheets for Deinking Agent Development, 20PEERS Conference
The Usefulness of Two-Side ERIC Buchner Handsheets for Deinking Agent Development, 20PEERS Conference
Conference papers
Incorporation of Post-Consumer Pizza Boxes in the Recovered Fiber Stream: Impacts of Grease on Finished Product Quality, 20PEERS Conference
Incorporation of Post-Consumer Pizza Boxes in the Recovered Fiber Stream: Impacts of Grease on Finished Product Quality, 20PEERS Conference
Conference papers
Rehabilitating Aging Plant Pipelines with Minimal Operational Downtime, 20PEERS Conference
Rehabilitating Aging Plant Pipelines with Minimal Operational Downtime, 20PEERS Conference
Conference papers
DEVELOPMENT OF CONVERGING-DIVERGING MULTI-JET NOZZLES FOR MOLTEN SMELT SHATTERING IN KRAFT RECOVERY BOILERS, 20PEERS Conferene
DEVELOPMENT OF CONVERGING-DIVERGING MULTI-JET NOZZLES FOR MOLTEN SMELT SHATTERING IN KRAFT RECOVERY BOILERS, 20PEERS Conferene
Conference papers
Impact of Ozone Bleaching on Effluent Discharge, 20PEERS Conference
Impact of Ozone Bleaching on Effluent Discharge, 20PEERS Conference