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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
Magazine articles
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
Tailoring Fiber Properties to Paper Manufacture: Recent Deve
Tailoring Fiber Properties to Paper Manufacture: Recent Developments, 1995 Pulping Conference Proceedings
Journal articles
Practical windows and inhibitors for grade 2 titanium use in alkaline peroxide bleach solutions, TAPPI JOURNAL, November 1995, Vol. 78(11)
Practical windows and inhibitors for grade 2 titanium use in alkaline peroxide bleach solutions, TAPPI JOURNAL, November 1995, Vol. 78(11)
Journal articles
Some fundamental aspects of wood chipping, TAPPI JOURNAL, October 1995, Vol. 78(10)
Some fundamental aspects of wood chipping, TAPPI JOURNAL, October 1995, Vol. 78(10)
Journal articles
Steam drying and fluidized-bed calcination of lime mudâ??results of extended pilot studies, TAPPI JOURNAL, September 1995, Vol. 78(9)
Steam drying and fluidized-bed calcination of lime mud—results of extended pilot studies, TAPPI JOURNAL, September 1995, Vol. 78(9)
Journal articles
Monitoring the stability of a paper machine, TAPPI JOURNAL, April 1996, Vol. 79(4)
Monitoring the stability of a paper machine, TAPPI JOURNAL, April 1996, Vol. 79(4)
Journal articles
An expert system advises operators on process control conditions, TAPPI JOURNAL, April 1996, Vol. 79(4)
An expert system advises operators on process control conditions, TAPPI JOURNAL, April 1996, Vol. 79(4)
Journal articles
Short-run statistical process controlâ??a basic charting method, TAPPI JOURNAL, April 1996, Vol. 79(4)
Short-run statistical process control–a basic charting method, TAPPI JOURNAL, April 1996, Vol. 79(4)
Journal articles
Laboratory kraft pulping of juvenile tropical pines: pinus patula, p. tecunumanii, p. maximinoi, and p. chiapensis, TAPPI JOURNAL, April 1996, Vol. 79(4)
Laboratory kraft pulping of juvenile tropical pines: pinus patula, p. tecunumanii, p. maximinoi, and p. chiapensis, TAPPI JOURNAL, April 1996, Vol. 79(4)