Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Collections
Magazine articles
Photographic life-prediction matrix for forming fabrics, TAPPI JOURNAL, November 1997, Vol. 80(11)
Photographic life-prediction matrix for forming fabrics, TAPPI JOURNAL, November 1997, Vol. 80(11)
Magazine articles
An overview of the south african pulp and paper industry, TAPPI JOURNAL, April 1999, Vol. 82(4)
An overview of the south african pulp and paper industry, TAPPI JOURNAL, April 1999, Vol. 82(4)
Magazine articles
Retention aids for highspeed paper machines, TAPPI JOURNAL, April 1999, Vol. 82(4)
Retention aids for highspeed paper machines, TAPPI JOURNAL, April 1999, Vol. 82(4)
Magazine articles
Vision of the future, TAPPI JOURNAL, November 1996, Vol. 79(11)
Vision of the future, TAPPI JOURNAL, November 1996, Vol. 79(11)
Magazine articles
Technology affecting the bottom line was the focus for the tappi/isa-pupid pcE&i conference, TAPPI JOURNAL, August 1997, Vol. 80(8)
Technology affecting the bottom line was the focus for the tappi/isa-pupid pcE&i conference, TAPPI JOURNAL, August 1997, Vol. 80(8)
Magazine articles
Beauty or the beast: life after iso 9000, TAPPI JOURNAL, October 1994, Vol. 77(10)
Beauty or the beast: life after iso 9000, TAPPI JOURNAL, October 1994, Vol. 77(10)
Magazine articles
Emerging pulping and chlorine-free bleaching technologies: in search of the ideal pulp mill, TAPPI JOURNAL, July 1991, Vol. 74(7)
Emerging pulping and chlorine-free bleaching technologies: in search of the ideal pulp mill, TAPPI JOURNAL, July 1991, Vol. 74(7)
Journal articles
Magazine articles
Effects of tissue additives on copy paper forming and properties, TAPPI Journal February 2024
ABSTRACT: Laboratory tests were conducted in an effort to determine the effects on paper machine process attributes and the properties of paper made from recycled copy paper furnish upon the addition of chemical agents that are commonly used in the production of hygiene tissue products. Due to continuing growth in tissue and towel grades of paper, such agents are experiencing greater usage. Charge titration test results revealed that certain dry strength agents associated with tissue manufacturing have the potential to shift the balance of charge in papermaking furnish to less negative or even positive values. Creping adhesive was found to contribute to fine particle retention, especially when present at relatively high levels. Release aid and a polyacrylate dispersant had the opposite effect. Low addition levels of both a creping adhesive and a debonding agent surprisingly increased a wide range of strength attributes of paper handsheets in comparison to sheets prepared from unaltered recycled copy paper furnish. The debonding agent decreased paper strength at higher levels of addition. Such effects appear to depend not only on the expected effects of agents themselves, but also on how they affect the charge balance of the wet-end system.
Journal articles
Magazine articles
Quantification of hardwood black liquor contamination in pine black liquor, TAPPI Journal February 2024
ABSTRACT: The presence of hardwood black liquor contamination in pine black liquor can negatively impact brownstock washer and evaporator operation, as well as reduce soap separation and yield. It is also believed to negatively impact commercial kraft lignin production. It was desired to develop a method of quantitatively determining the amount of low-level hardwood liquor contamination in pine black liquor. A method employing pyrolysis-gas chromatography mass spectrometry (py-GCMS) was developed to perform the desired measurement. Laboratory cooks with carefully controlled blends of pine and hardwood chips were prepared, and the resulting liquor was measured using this technique. Additionally, samples of pine and hardwood black liquors were blended in known quantities and analyzed. All these samples were submitted as blind samples. The resulting analysis suggests the py-GCMS method was able to accurately determine the level of hardwood contamination between 1% to 10% hardwood liquor using a low-level calibration curve prepared with coniferyl alcohol and sinapyl alcohol as standards.
Journal articles
Magazine articles
Modeling the dynamics of evaporator wash cycles, TAPPI Journal July 2024
ABSTRACT: Kraft pulping is a process that utilizes white liquor, composed of sodium sulfide (Na2S) and sodium hydroxide (NaOH), for wood delignification and pulp production. This process involves washing the dissolved organics and spent chemicals from the pulp, resulting in the generation of black liquor. Prior to its use as fuel in the recovery boiler, the black liquor is concentrated in multiple-effect evaporators. During the evaporation process, the inorganic salts present in the liquor become supersaturated and undergo crystallization. Fluctuations in sodium, carbonate, sulfate, and oxalate can give rise to severe sodium salt scaling events, which significantly impact the thermal efficiency of the evaporators, and ultimately, pulp production. Dynamic modeling provides insights into fluctuations in liquor chemistry in the evaporators. The primary objective of this study was to employ dynamic modeling to evaluate the effects of wash liquor recovery from evaporator wash cycles. The dynamics associated with wash cycles encompass variations in the concentrations of salts and solids in the recovered wash liquor, changes in the flow rate of wash liquor recovery, and fluctuations in liquor volume within the liquor tanks. The dynamic model was developed using Matlab Simulink and applied to the evaporation plant of a pulp mill in South America. By utilizing one month of mill process data, the model enabled the evaluation of fluctuations in liquor chemistry due to evaporator wash cycles. The developed model has demonstrated the potential to estimate the concentration of key ions responsible for scaling and to contribute to enhancements in evaporator washing strategies.