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Guest Editorial: Paper and bioprocess engineering at SUNY-ES
Guest Editorial: Paper and bioprocess engineering at SUNY-ESF, TAPPI JOURNAL January 2012
Magazine articles
China: now and in the future, TAPPI JOURNAL, May 1996, Vol. 79(5)
China: now and in the future, TAPPI JOURNAL, May 1996, Vol. 79(5)
Magazine articles
On-line corrosion monitoring in kraft white liquor clarifiers, TAPPI JOURNAL, June 1996, Vol. 79(6)
On-line corrosion monitoring in kraft white liquor clarifiers, TAPPI JOURNAL, June 1996, Vol. 79(6)
Magazine articles
Comprehensive safety training programs, TAPPI JOURNAL, July 1996, Vol. 79(7)
Comprehensive safety training programs, TAPPI JOURNAL, July 1996, Vol. 79(7)
Magazine articles
Editor's Notes: Paperless or Paper More?, TAPPI JOURNAL, Feb
Editor's Notes: Paperless or Paper More?, TAPPI JOURNAL, February 2005, Vol. 4(2)
Magazine articles
Challenges and opportunities for china's paper industry, TAPPI JOURNAL, October 2000, Vol. 83(10)
Challenges and opportunities for china's paper industry, TAPPI JOURNAL, October 2000, Vol. 83(10)
Magazine articles
Proper design and use of suction roll sealing strips in suction roll operation, TAPPI JOURNAL, November 1996, Vol. 79(11)
Proper design and use of suction roll sealing strips in suction roll operation, TAPPI JOURNAL, November 1996, Vol. 79(11)
Magazine articles
Chemically structured kaolin: a new coating pigment, TAPPI JOURNAL, February 1990, Vol. 73(2)
Chemically structured kaolin: a new coating pigment, TAPPI JOURNAL, February 1990, Vol. 73(2)
Magazine articles
Highly corrosion-resistant metals for the pulp and paper industry, TAPPI JOURNAL, March 1991, Vol. 74(3)
Highly corrosion-resistant metals for the pulp and paper industry, TAPPI JOURNAL, March 1991, Vol. 74(3)
Journal articles
Magazine articles
Effects of different soda loss measurement techniques on brownstock quality, TAPPI Journal July 2024
ABSTRACT: The efficiency of the kraft recovery plant, bleaching process, and paper machine are affected when black liquor carryover from the brownstock washers is not controlled well. Measuring soda loss within a mill can vary from using conductivity, either in-situ or with a lab sample of black liquor filtrate squeezed from the last stage washer, to measuring absolute sodium content with a lab sodium specific ion probe or spectrophotometer. While measuring conductivity has value in tracking trends in black liquor losses, it is not an acceptable method in reporting losses in absolute units, typically in lb/ton of pulp. This is further complicated when trying to benchmark soda loss performance across a fleet of mills with multiple washer lines. Not only do the testing methods vary, but the amount of bound soda on high kappa pulps can be significant. This variability creates inconsistent results, and studies are needed to understand the effect of different testing methods on the pulp quality. In this study, soda loss is expressed as sodium sulfate (Na2SO4). Four different methods to measure soda content in pulp off commercial brownstock washers were studied: full digestion (FD), washing soaking overnight and washing (WSW), soaking in boiling water and stirring 10-min (SW-10), and squeeze-no wash (Sq). Total, washable, and bound sodium sulfate calculations were determined for each soda content measuring technique using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results showed bound and washable sodium sulfate amounts significantly depend on which soda measurement technique was used. In addition, the soda results were correlated with the pulp kappa numbers. As the kappa number increases, bound soda increases, regardless of the soda measurement method used. Impacts of high sodium sulfate in brownstock are also discussed.
