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Journal articles
Examination of the potential to reduce water application rat
Examination of the potential to reduce water application rates for hardwood pulp logs stored in wet decks, TAPPI JOURNAL August 2016
Journal articles
Alkyl ketene dimer (AKD) sizing of paper under simplified tr
Alkyl ketene dimer (AKD) sizing of paper under simplified treatment conditions, TAPPI JOURNAL August 2016
Journal articles
Effect of sheet temperature on web densification during ca
Effect of sheet temperature on web densification during calendering, TAPPI JOURNAL February 2016
Journal articles
Support vector regression and model reference adaptive contr
Support vector regression and model reference adaptive control for optimum control of nonlinear drying process, TAPPI JOURNAL February 2016
Journal articles
Biochemical methane potential of kraft bleaching effluent a
Biochemical methane potential of kraft bleaching effluent and codigestion with other in-mill streams, TAPPI JOURNAL February 2016
Journal articles
Causes of back-trap mottle in lithographic offset prints on
Causes of back-trap mottle in lithographic offset prints on coated papers, TAPPI JOURNAL February 2016
Journal articles
A method to produce paperboard with a lightweight low-density coating, TAPPI Journal November 2025
ABSTRACT: In this work, a method is described in which a coating layer is produced that consists of a network of bubble-shaped air-filled voids within the coating. This is accomplished by instantaneously flash-drying all the water in the coating as it exits the application nip. The nip is formed between a polished chrome drum and a deformable press roll. The combination of the drum temperature, nip pressure, and nip width allow for sufficient energy to be transferred to the coating to completely flash-dry the coating material. The pressure within the nip is sufficient to allow the coating to superheat within the nip, then flash boil as it exits the nip. This boiling effect and resulting expansion are constrained by the roll surface, resulting in a coated surface that mirrors the polished chrome surface. The coating immobilizes while in the process of boiling, which preserves the bubble structure. With a coat weight of 5 g/m2, a flat, smooth surface is produced. This process was scaled up to a mill production machine layout and run at speeds as high as 450 m/min.
Journal articles
Pre-damping effects on water absorption and drying dynamics in flexographic printing, TAPPI Journal November 2025
ABSTRACT: Optimizing flexographic printability can involve the ink and the substrate, as well as the printing process. It has been widely reported in the literature that controlling topography of the substrate and its porosity are vital for good flexographic printability, especially when using water-based inks. This study focuses on how pre-damping a surface impacts liquid absorption and improves wet trapping (ink on ink with no intermediate drying) in flexographic printing. A Prüfbau universal print tester was adapted to analyze flexographic wet-on-wet ink printing and trapping using yellow and magenta inks for contrast. Slow drying of the first ink layer (yellow) leads to mottle when the second layer (magenta) is applied. The study explores the “wet sponge” hypothesis: a pre-damped surface should absorb liquid faster. The Lucas- Washburn equation describes long-term absorption, but it does not capture short-term uptake, which instead follows a linear dependence on time.
Journal articles
ABSTRACT: This study investigates the impact of pulp screening on oxygen delignification of high lignin content kraft pulps from spruce wood. An alternative process is proposed: terminating kraft cooking at higher kappa numbers and applying oxygen deligni
ABSTRACT: This study investigates the impact of pulp screening on oxygen delignification of high lignin content kraft pulps from spruce wood. An alternative process is proposed: terminating kraft cooking at higher kappa numbers and applying oxygen delignification directly to unscreened and non-defibrated pulp. The objective is to evaluate whether this non-standard approach can maintain delignification efficiency while improving yield and reducing energy input. The findings demonstrate that screening prior to oxygen delignification is not essential for effective lignin removal or pulp quality. Similar delignification degrees and ISO brightness levels were obtained after oxygen delignification, whether it was performed on screened or unscreened pulps. Notably, the delignification rate in the oxygen stage was the same for the non-standard procedure as for pulp from the standard procedure with the reject fractionremoved prior to the oxygen stage. No significant differences were seen in fiber morphology, brightness level, orbrightness stability. The amount of total fiber charges in pulps not screened before oxygen delignification was slightly higher than in screened pulps.
Journal articles
ABSTRACT: Lignin’s potential as a source of sustainable aromatic compounds is significant, but its utilization is currently limited by its chemical reactivity. Chemical reactivity of lignin depends on the present functional groups, such as hydroxyl, metho
ABSTRACT: Lignin’s potential as a source of sustainable aromatic compounds is significant, but its utilization is currently limited by its chemical reactivity. Chemical reactivity of lignin depends on the present functional groups, such as hydroxyl, methoxy, and carbonyl groups. Therefore, in this study, multivariate analysis-based chemometric models have been developed for rapid determination of aliphatic hydroxyl (Alp-OH) and phenolic hydroxyl (Ph-OH) groups in lignin samples. Two chemometric models, principal component regression (PCR) and partial least squares regression (PLSR), were established with Fourier transform infrared spectroscopy (FTIR) spectral data of 28 lignin samples. Both the models were developed based on raw and pretreated spectroscopic data with Savitky-Golay (S-G) filtering and standard normal variate (SNV) and multiplicative scatter correction (MSC). The predictive performance of the PLSR model is better for predicting Alp-OH (R2 = 0.94%), syringyl-OH (R2 = 0.96%), guaiacyl-OH (R2 = 0.98%), p-hydroxyphenyl (R2 = 0.93%), and total Ph-OH groups (R2 = 0.97%) with the data pretreated by MSC. Finally, the predicted results of these parameters for three new samples for the developed models are found to be very close to the estimated values by NMR.