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Magazine articles
Advanced real-time digital microscopy of foaming processes, TAPPI Journal January 2023
ABSTRACT: The properties of aqueous foams play a major role in foam forming and foam coating. Inline real-time foam measurements provide highly desired opportunities for optimization and control of foaming processes. This paper presents inline digital microscopy measurements of aqueous foams in foaming processes. It presents methods for providing detailed information on foam quality parameters, such as foam density and foam homogeneity in real time from the process. In addition, this study evaluates the performance of transillumination and front-light illumination in imaging of foams. The tests show very good results for the transillumination approach. Limitations of the image-based optical technique are discussed, and the precision of bubble size distribution measurement is assessed with a certificated reference substance. The measured foam densities are compared against the reference foam densities in the range 100•300 g/L, providing a linear correlation with R2 value of 0.99. In the case of heterogenous foams with a wide bubble size distribution, the bubble size-dependent dimensionless depth of field must be taken into account to obtain accurate estimates of foam density. Bubble-scale foam homogeneity is described by the standard deviation of bubble size distribution in foam.
Journal articles
Magazine articles
Chemical addition to wet webs using foam application, TAPPI Journal January 2023
ABSTRACT: In papermaking, the conventional way to add chemicals to the web is to dose them into the fiber stock and form the paper afterwards. However, in many cases, adding chemicals directly to the stock is challenging. For example, strength aids tend to increase flocculation in the stock, which limits the addition amounts of those aids. The need for better performance of paper (and paperboard) products has given rise to the need for functionalization of paper. Adding such functional chemicals to the stock is usually rather inefficient. Hence, novel methods are needed to add chemicals to the paper bulk. One such method is dosing chemicals to the wet web via foam application. In this study, we built a laboratory-scale sheetfed dynamic foam application device and utilized it to study addition of starch to wet bleached chemithermomechanical pulp (BCTMP) paper handsheets. The impact of parameters such as vacuum level, the amount of added chemical, and the viscosity of the foaming liquid on the penetration of starch into the wet web was explored. Starch penetration into wet webs was measured via iodine-potassium iodide staining, followed by image analysis. According to our results, controlling the viscosity of the foaming liquid gives the best possibility to control the penetration.
Magazine articles
The corrosion behavior of titanium (grade 2) in alkaline peroxide bleach liquors, TAPPI JOURNAL, June 1995, Vol. 78(6)
The corrosion behavior of titanium (grade 2) in alkaline peroxide bleach liquors, TAPPI JOURNAL, June 1995, Vol. 78(6)
Magazine articles
Chemical recovery conference emphasizes high solids firing and mill system closure, TAPPI JOURNAL, August 1995, Vol. 78(8)
Chemical recovery conference emphasizes high solids firing and mill system closure, TAPPI JOURNAL, August 1995, Vol. 78(8)
Magazine articles
Factors affecting the fabrication of corrosion barriers for rp equipment in bleaching environments, TAPPI JOURNAL, September 1995, Vol. 78(9)
Factors affecting the fabrication of corrosion barriers for rp equipment in bleaching environments, TAPPI JOURNAL, September 1995, Vol. 78(9)
Magazine articles
Finishing and converting division conference celebrates 25th anniversary, TAPPI JOURNAL, February 1992, Vol. 75(2)
Finishing and converting division conference celebrates 25th anniversary, TAPPI JOURNAL, February 1992, Vol. 75(2)
Magazine articles
Annual tappi papermakers conference held in nashville, TAPPI JOURNAL, August 1992, Vol. 75(8)
Annual tappi papermakers conference held in nashville, TAPPI JOURNAL, August 1992, Vol. 75(8)
Magazine articles
ISO 9000 registration-avoiding unnecessary procedures, TAPPI JOURNAL, November 1996, Vol. 79(11)
ISO 9000 registration-avoiding unnecessary procedures, TAPPI JOURNAL, November 1996, Vol. 79(11)
Magazine articles
ECF results please gruvon mill, TAPPI JOURNAL, January 1995, Vol. 78(1)
ECF results please gruvon mill, TAPPI JOURNAL, January 1995, Vol. 78(1)
Magazine articles
1995 looks good for corrugated and solid-fiber box production and folding paperboard boxes, TAPPI JOURNAL, April 1995, Vol. 78(4)
1995 looks good for corrugated and solid-fiber box production and folding paperboard boxes, TAPPI JOURNAL, April 1995, Vol. 78(4)
