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Magazine articles
Evaluation of soap recovery efficiency from black liquor — analytical tools, TAPPI Journal April 2023
ABSTRACT: Soap skimmings (“soap”) are typically recovered from black liquor in kraft mills that process a high percentage of softwood. In many mills, the recovery of soap is inefficient, negatively impacting performance of evaporators and recovery boilers and resulting in loss of potential revenue. A thorough evaluation of soap recovery performance in a kraft mill requires measurement of soap content in black liquor at various sampling locations, especially around the soap skimmer.The standard laboratory method for evaluating soap content in black liquor is a complex, multi-step process that relies on solvent extraction and titration; most mills send these samples to an outside laboratory for this analysis. In this study, 100 black liquor samples, with a wide range of soap concentrations, were tested by the standard solvent extraction method. After additional dilution, each sample was also tested for surface tension with a bubble pressure tensiometer. The results were found to correlate very closely with the solvent extraction tests results. This alternate method, using surface tension measurements of diluted black liquor samples, produces rapid results and can be easily implemented in most kraft mills, which would facilitate much more frequent in-house evaluations of soap recovery performance.
Journal articles
Magazine articles
How do mud balls form in lime kilns?, TAPPI Journal April 2023
ABSTRACT: Mud ball formation in lime kilns has been a persistent problem in many kraft mills, particularly for older kilns that are equipped with chains. A systematic laboratory study was conducted to examine how mud balls are formed and the key factors that affect ball formation. The results confirm the general mill experience that high moisture and high sodium contents in lime mud are the main contributing factors to ball formation. The high moisture content allows lime mud to agglomerate and grow to form balls, while the high sodium content helps make the balls hard and retain their shape. A ball formation mechanism is proposed to explain how mud balls form and grow near the kiln feed end.
Journal articles
Mill study on improving lime kiln efficiency 15FEB133
Mill study on improving lime kiln efficiency, TAPPI JOURNAL February 2015
Journal articles
Bond strength of oxygen-delignified kraft pulps, TAPPI JOURNAL, February 1999, Vol. 82(2)
Bond strength of oxygen-delignified kraft pulps, TAPPI JOURNAL, February 1999, Vol. 82(2)
Journal articles
The polish pulp and paper industry, TAPPI JOURNAL, February 1999, Vol. 82(2)
The polish pulp and paper industry, TAPPI JOURNAL, February 1999, Vol. 82(2)
Journal articles
Results of Automatic Dirt Counting Using Transmitted Light, TAPPI JOURNAL, January 1999, Vol. 83(5)
Results of Automatic Dirt Counting Using Transmitted Light, TAPPI JOURNAL, January 1999, Vol. 83(5)
Journal articles
Effect of differences in climate on growth, wood, and pulp properties of nine eucalypt species at two sites, TAPPI JOURNAL, July 1999, Vol. 82(7)
Effect of differences in climate on growth, wood, and pulp properties of nine eucalypt species at two sites, TAPPI JOURNAL, July 1999, Vol. 82(7)
Journal articles
Air removal mill trials using pomp deaerator, TAPPI JOURNAL, June 1999, Vol. 82(6)
Air removal mill trials using pomp deaerator, TAPPI JOURNAL, June 1999, Vol. 82(6)
Journal articles
Modern converting equipment and controls for source and waste reduction, TAPPI JOURNAL, June 1999, Vol. 82(6)
Modern converting equipment and controls for source and waste reduction, TAPPI JOURNAL, June 1999, Vol. 82(6)
Journal articles
Cationic latex as a mulitifunctional papermaking wet-end additive, TAPPI JOURNAL, March 1999, Vol. 82(3)
Cationic latex as a mulitifunctional papermaking wet-end additive, TAPPI JOURNAL, March 1999, Vol. 82(3)