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SetPoint: That’s My Jam, November/December 2023 Paper360º

Effects of rings on flow and temperature in lime kilns, TAPPI Journal June 2022

ABSTRACT: A steady state, two-dimensional (2D) axisymmetric model has been developed to help understand how rings form and grow in a typical lime kiln. Rings of varying length, thickness, and geometry at the front and back faces were modeled to study the effects on flue gas flow and temperature. The results show that ring growth causes the gas velocity to increase and insulates the adjacent refractory, resulting in a lower kiln shell temperature. The results also reveal the formation of recirculation zones immediately down-stream of the rings, as well as temperature deviations upstream and downstream of the rings that might promote recarbonation and further ring growth. The model was applied to a kiln from a kraft mill with front-end and mid-kiln rings and good agreement was obtained between the measured and predicted kiln shell temperatures, providing confidence in the modeling.

Web instability in the open draw and the impact on paper machine efficiency, TAPPI Journal May 2022

ABSTRACT: Paper is most likely to break in the first open draw on a paper machine where it is unsupported, wettest, and weakest. Tension is applied to peel the web from the roll surface, as well as minimize web flutter in the open draw. The average tension is well below the breaking point and is often set by adjusting the speed difference between the press and the next machine element by visually observing the behavior of the web. However, machine direction variations caused by instabilities in the paper machine can cause tension swings that exceed the strength of the web. Measurement of the web’s release point from press rolls on pilot and commercial paper machines was used to identify the cause of tension instabilities. Variations in the speed of the paper machine drives and the work of adhesion from the press roll surface were identified as key factors. Fluctuations of paper moisture, which affects the elastic modulus and strength of the web, appear to be less important.

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.

Static and dynamic sorption of lignin removed Populus euramericana, TAPPI JOURNAL February 2018

Static and dynamic sorption of lignin removed Populus euramericana, TAPPI JOURNAL February 2018

Combustion behavior of kraft black liquor droplets from hot

Combustion behavior of kraft black liquor droplets from hot water pretreated hardwood and softwood chips, November 2016 TAPPI JOURNAL

Novel CaCO3-polymer nanocomposite fillers for the improvemen

Novel CaCO3-polymer nanocomposite fillers for the improvement of bagasse-based papers, November 2016 TAPPI JOURNAL

Understanding conductivity and soda loss

Understanding conductivity and soda loss

Taison Group’s Twin PrimeLineSTs Bamboo Tigers, Tissue360º Spring/Summer 2019

Taison Group’s Twin PrimeLineSTs Bamboo Tigers, Tissue360º Spring/Summer 2019

When Operations Runs Maintenance, Paper360º January/February 2019

When Operations Runs Maintenance, Paper360º January/February 2019