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Manufacturing of the Future: A Manager and His Dog?, Paper360º November/December 2019
Manufacturing of the Future: A Manager and His Dog?, Paper360º November/December 2019
Journal articles
Magazine articles
Editorial: TAPPI Journal goes Open Access in 2020, TAPPI Journal October 2019
ABSTRACT: Scientific publishing has changed significantly since the 1990s with the evoluation of the internet, which has largely migrated journals from subscription-based print publications to online content like eBooks, portable document formats (PDFI's), and web-based HTML files. Along with these changes in format has come a growing trend for online journal content to be either partially or fully "Open Access" (OA) so that more institutions and individuals can take full advantage of scholarly literature without a subscription of society membership status.
Journal articles
Magazine articles
Evaluation of novel drum chipper technology: pilot-scale production of short wood chips, TAPPI Journal October 2019
ABSTRACT: Impregnation of wood chips with acidic pulping liquors is improved when using short chip lengths. If the average wood chip length is too short, conventional chipping technology will generate excess small material, such as pin chips and fines. The possibility of using newly developed drum chipping technology to produce short-length wood chips was evaluated with a pilot drum chipper operating at different drum velocities and in-feed angles. With a drum velocity of 30 m/s, the average wood chip lengths and the combined fractions of pin chips and fines were 24 mm and 3.3%, 22 mm and 4.2%, and 17 mm and 8.5%. The highest fractions of total accept chips (large and small accepts), 89% to 90% without screening, were observed for drum velocities of 30•34 m/s and average wood chips lengths of 21•22 mm. The results indicate the potential of drum chipping technology for producing short wood chips with relatively high fractions of accept chips and tolerable fractions of pin chips and fines.
Journal articles
Magazine articles
Exergy and sensibility analysis of each individual effect in a kraft multiple effect evaporator, TAPPI Journal October 2019
ABSTRACT: The multiple effect evaporator (MEE) is an energy intensive step in the kraft pulping process. The exergetic analysis can be useful for locating irreversibilities in the process and pointing out which equipment is less efficient, and it could also be the object of optimization studies. In the present work, each evaporator of a real kraft system has been individually described using mass balance and thermodynamics principles (the first and the second laws). Real data from a kraft MEE were collected from a Brazilian plant and were used for the estimation of heat transfer coefficients in a nonlinear optimization problem, as well as for the validation of the model. An exergetic analysis was made for each effect individually, which resulted in effects 1A and 1B being the least efficient, and therefore having the greatest potential for improvement. A sensibility analysis was also performed, showing that steam temperature and liquor input flow rate are sensible parameters.
Journal articles
Magazine articles
Editorial: A preview of PEERS 2019, TAPPI Journal September 2019
ABSTRACT: Coming soon is PEERS • TAPPI’s annual Pulping, Engineering, Environmental, Recycling and Sustainability gathering for industry professionals. Held this October 27-30 in St. Louis, MO, the conference is co-located with the International Bioenergy & Bioproducts Conference (IBBC) and the 12th Research Forum on Recycling. Universities and research organizations from around the world are represented in the conference content, and below is a sampling of just a few of the many presentations that might interest TAPPI Journal readers.
Journal articles
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Critical parameters for tall oil separation I: The importance of ration of fatty acids to rosin acids, TAPPI Journal September 2019
ABSTRACT: Tall oil is a valuable byproduct in chemical pulping of wood, and its fractions have a large spectrum of applications as chemical precursors, detergents, and fuel. High recovery of tall oil is important for the economic and environmental profile of chemical pulp mills. The purpose of this study was to investigate critical parameters of tall oil separation from black liquor. To investigate this in a controlled way, we developed a model test system using a “synthetic” black liquor (active cooking chemicals OH- and HS- ions), a complete process for soap skimming, and determination of recovered tall oil based on solvent extraction and colorimetric analysis, with good reproducibility. We used the developed system to study the effect of the ratio of fatty acids to rosin acids on tall oil separation. When high amounts of rosin acids were present, tall oil recovery was low, while high content of fatty acids above 60% significantly promoted tall oil separation. Therefore, manipulating the content of fatty acids in black liquor before the soap skimming step can significantly affect the tall oil solubility, and hence its separation. The findings open up chemical ways to improve the tall oil yield.
Journal articles
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A new technique for the measurement of show-through mottle of fine paper, TAPPI Journal September 2019
ABSTRACT: Mottling within print-through and show-through is caused by the variability of the local optical properties of the sheet. This mottling is visually disturbing and a mark of poor paper quality. The ability to predict print-through mottle of printed paper by measuring show-through mottle on the unprinted sheet would be a valuable asset for paper machine control.We examined the relationship between print-through mottle and show-through mottle. We worked with nine samples of 60 lb. uncoated fine paper (90 g/m2), from various North American paper companies, that were printed on an offset press, 400K (400% Black), on both sides. A show-through mottle instrumental determination technique was developed using an existing Fast Fourier Transform-based algorithm. The nine samples examined were ranked similarly by the visual evaluation of print-through mottle and by the instrumental determination of show-through mottle. We thus established that show-through on the unprinted sheet can be used as a reliable predictor of print-through, therefore saving time and money for papermakers. We also found a significant two-sidedness in show-through for some of the samples.
Journal articles
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SIF Prevention Program Focuses on What Matters Most, Paper360º September/October 2019
SIF Prevention Program Focuses on What Matters Most, Paper360º September/October 2019
Journal articles
Magazine articles
He’s Got the Pulp: Schalka Sets Record as LA CEO of the Year, Paper360º September/October 2019
He’s Got the Pulp: Schalka Sets Record as LA CEO of the Year, Paper360º September/October 2019
Journal articles
Magazine articles
IDEAS Digital Twin Technology for Evaporation Plants, Paper360º September/October 2019
IDEAS Digital Twin Technology for Evaporation Plants, Paper360º September/October 2019