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Journal articles
Hydrogen-peroxide-reinforced oxygen delignification of southern pine kraft pulp and short sequence bleaching, TAPPI JOURNAL, July 1990, Vol. 73(7)
Hydrogen-peroxide-reinforced oxygen delignification of southern pine kraft pulp and short sequence bleaching, TAPPI JOURNAL, July 1990, Vol. 73(7)
Journal articles
Heavy metal analysis of inks: a survey, TAPPI JOURNAL, April 1992, Vol. 75(4)
Heavy metal analysis of inks: a survey, TAPPI JOURNAL, April 1992, Vol. 75(4)
Journal articles
Predictive maintenance: monitoring the health of gear drives, TAPPI JOURNAL, August 1992, Vol. 75(8)
Predictive maintenance: monitoring the health of gear drives, TAPPI JOURNAL, August 1992, Vol. 75(8)
Journal articles
Kinetic studies on soda-anthraquinone pulping of indian mixed hardwoods, TAPPI JOURNAL, August 1992, Vol. 75(8)
Kinetic studies on soda-anthraquinone pulping of indian mixed hardwoods, TAPPI JOURNAL, August 1992, Vol. 75(8)
Journal articles
An improved process for converting cellulose to ethanol, TAPPI JOURNAL, August 1992, Vol. 75(8)
An improved process for converting cellulose to ethanol, TAPPI JOURNAL, August 1992, Vol. 75(8)
Journal articles
Making the right choices for successful bagasse newsprint production: part 1, TAPPI JOURNAL, December 1992, Vol. 75(12)
Making the right choices for successful bagasse newsprint production: part 1, TAPPI JOURNAL, December 1992, Vol. 75(12)
Journal articles
Potential of enzymes for wood debarking, TAPPI JOURNAL, February 1993, Vol. 76(2)
Potential of enzymes for wood debarking, TAPPI JOURNAL, February 1993, Vol. 76(2)
Journal articles
Magazine articles
Considerations in managing wastewater odor at pulp and paper operations, TAPPI Journal March 2022
ABSTRACT: Many pulp and paper mills are, at least periodically, faced with the release of odors that can migrate offsite and be considered a nuisance by nearby residents. At chemical pulp mills, perceptible odors associated with reduced sulfur compounds (RSCs) are common, many of which are highly perceptible owing to their low odor thresholds. As releases of RSCs and other odorous substances from production processes are progressively controlled, the proportional contribution from wastewater treatment systems to areal odors can increase. This review paper summarizes important fundamentals of odor generation, source identification, and control. Common odorous substances are identified, and mechanisms for their generation are summarized. Approaches for measuring odorous substances are detailed to enable more effective management, and various odor control strategies are discussed.
Journal articles
Effects of calcium on sodium salt scaling with the presence of resin acids and fatty acids, TAPPI Journal June 2026
ABSTRACT: Reintroducing tall oil soap or its related products into high dry solids black liquor has been found to reduce sodium salt scaling in falling film evaporators. Aside from resin acids and fatty acids, which are the likely scale inhibitors, calcium is reintroduced into black liquor because of the relatively high calcium content of tall oil soap. One concern is that this increase in calcium content might lead to the formation of additional calcium and sodium scales in evaporators. In this work, we investigated the relationship among trace amounts of calcium, sodium salts, resin acids, and fatty acids in a controlled system using a model salt solution and a benchtop setup. We studied the effects of the calcium carbonate addition and calcium carbonate scales on sodium salt scaling in the presence of resin acids and fatty acids. We found that some calcium carbonate is incorporated in the precipitated sodium crystals, and the suspended sodium crystals become larger and more compact with increasing calcium carbonate concentration. Experiments in the benchtop setup show that precipitating calcium carbonate scale on the heat exchanger does not lead to a higher rate of sodium salt scaling. The solubility of calcium carbonate is not affected by the addition of resin acids and fatty acids. These findings indicate that the reduction in sodium salt scaling through the addition of tall oil soap is primarily related to resin acids and fatty acids, rather than to calcium or to interactions between calcium and mixtures of resin and fatty acids.
Journal articles
Optimization of optical coverage of board surfaces with assessment of light scattering and absorption using mineral as a coating component, TAPPI Journal June 2026
ABSTRACT: One of the primary functions of mineral inclusion into paper or paperboard is to improve the optical performance of the substrate. A coating may be applied to a sheet in order to cover a dark base, to improve the sheet opacity, to give the correct smoothness and gloss, or to give a suitable surface on which to print. The brightness of a pigment has long been used as a guide for pigment choice in paper and board. However, the measured paper brightness is a function of color and light absorption (K) of the coating and base and the light scattering (S) within the sheet resulting from interfaces with different refractive index. The optical performance can be quantified by measuring the S&K coefficients as described by the Kubelka-Munk model/theory in a filled or coated paper sheet. In coating, this is often assessed as a function of coat weight, and the corresponding physical sheet properties are assessed at the same time; for example, the correct gloss, smoothness, point-to-point uniformity, and printability. The optical performance in the sheet is often not directly related to the pigment brightness, but is largely a function of the particle packing within the sheet and coating layer. In the first and second main sections of this work, respectively, we show how S&K calculations from the Kubelka- Munk equations can be used in coated sheets to determine the optical performance and how this can be used as a predictive tool for the final sheet performance. This is presented for base sheets with different starting brightness. The third section of this work focuses on how mineral combinations in coatings can be used to improve the light scattering and consequently the optical performance of the board. We include theoretical considerations and then finally share a case study for improvement on the optical properties of recycled board.