Search

Use the search bar or filters below to find any TAPPI product or publication.

Showing 1–10 of 2,529 results (Duration : 0.049 seconds)
Journal articles
Magazine articles
Open Access
Experiments and visualization of sprays from beer can and turbo liquor nozzles, TAPPI Journal February 2022

ABSTRACT: Industrial scale swirl-type black liquor nozzles were studied using water as the test fluid. Simple water spraying experiments were found to be very beneficial for studying and comparing nozzles for black liquor spraying. These kinds of experiments are important for finding better nozzle designs. Three nozzle designs were investigated to understand the functional differences between these nozzles. The pressure loss of nozzle 1 (“tangential swirl”) and nozzle 3 (“turbo”) were 97% and 38% higher compared to nozzle 2 (“tan-gential swirl”). Spray opening angles were 75°, 60°, and 35° for nozzles 1, 2, and 3, respectively. Video imaging showed that the nozzles produced sprays that were inclined a few degrees from the nozzle centerline. Spray patter-nation showed all the sprays to be asymmetric, while nozzle 2 was the most symmetric. Laser-Doppler measure-ments showed large differences in spray velocities between nozzles. The spray velocity for nozzle 1 increased from 9 m/s to 15 m/s when the flow rate was increased from 1.5 L/s to 2.5 L/s. The resulting velocity increase for nozzle 2 was from 7 m/s to 11 m/s, and for nozzle 3, it was from 8 m/s to 13 m/s. Tangential flow (swirl) directed the spray 6°–12° away from the vertical plane. Liquid sheet breakup mechanisms and lengths were estimated by analyzing high speed video images. The liquid sheet breakup mechanism for nozzle 1 was estimated to be wave formation, and the sheet length was estimated to be about 10 cm. Sheet breakup mechanisms for nozzle 2 were wave formation and sheet perforation, and the sheet length was about 20 cm. Nozzle 3 was not supposed to form a liquid sheet. Nozzle geometry was found to greatly affect spray characteristics.

Journal articles
Magazine articles
Open Access
Displacement washing of softwood pulp cooked to various levels of residual lignin content, TAPPI Journal September 2021

ABSTRACT: This study investigates the influence of the degree of delignification of kraft spruce pulp cooked at seven different kappa numbers, ranging from 18.1 to 50.1, on the efficiency of displacement washing under laboratory conditions. Although the pulp bed is a polydispersive and heterogeneous system, the correlation dependence of the wash yield and bed efficiency on the Péclet number and the kappa number of the pulp showed that washing efficiency increased not only with an increasing Péclet number, but also with an increasing kappa number. The linear dependence between the mean residence time of the solute lignin in the bed and the space time, which reflects the residence time of the wash liquid in the pulp bed, was found for all levels of the kappa number. Washing also reduced the kappa number and the residual lignin content in the pulp fibers.

Journal articles
Open Access
Statistical determination of the effects of enzymes on bleached pulp yield, TAPPI JOURNAL, August 2005, Vol. 4(8) (80 KB)

Statistical determination of the effects of enzymes on bleached pulp yield, TAPPI JOURNAL, August 2005, Vol. 4(8) (80 KB)

Journal articles
Open Access
Alkaline peroxide mechanical pulping of wheat straw Part 2: significance of peroxide stabilization to the brightening of wheat straw, TAPPI JOURNAL, July 2000, Vol. 83(7)

Alkaline peroxide mechanical pulping of wheat straw Part 2: significance of peroxide stabilization to the brightening of wheat straw, TAPPI JOURNAL, July 2000, Vol. 83(7)

Journal articles
Open Access
Advanced combustion and flow modeling: comprehensive model study improves recovery boiler operation, TAPPI JOURNAL, July 2000, Vol. 83(7)

Advanced combustion and flow modeling: comprehensive model study improves recovery boiler operation, TAPPI JOURNAL, July 2000, Vol. 83(7)

Journal articles
Open Access
Improved ozone efficiency at reduced charges -- an electrochemical model and new experimental approach, TAPPI JOURNAL, September 2000, Vol. 83(9)

Improved ozone efficiency at reduced charges -- an electrochemical model and new experimental approach, TAPPI JOURNAL, September 2000, Vol. 83(9)

Journal articles
Open Access
Pulping of aspen wood in acetic acid media: effect of operating conditions on yield and pulp properties, TAPPI JOURNAL, December 2000, Vol. 83(12)

Pulping of aspen wood in acetic acid media: effect of operating conditions on yield and pulp properties, TAPPI JOURNAL, December 2000, Vol. 83(12)

Journal articles
Open Access
An image analysis method to quantify fibre separation in wood subjected to fatigue loading, TAPPI JOURNAL, December 2000, Vol. 83(12)

An image analysis method to quantify fibre separation in wood subjected to fatigue loading, TAPPI JOURNAL, December 2000, Vol. 83(12)

Journal articles
Open Access
Black Liquor Recovery by Pressurized, Oxygen-Blown Gasificat

Black Liquor Recovery by Pressurized, Oxygen-Blown Gasification, 1996 Engineering Conference Proceedings

Journal articles
Open Access
Correlation Between Nodule size and Residual Carbonate Content in Lime Kilns, TAPPI JOURNAL, April 2007

Correlation Between Nodule size and Residual Carbonate Content in Lime Kilns, TAPPI JOURNAL, April 2007