Home » Volume 27, 2012 » Issue No. 5
Development of TMP fibers in LC- and HC- refining
Rita Ferritsius, Sofia Reyier Österling, Olof Ferritsius
Low consistency (LC) refining and high consistency refining (HC) has been studied in a TMP mill. When strength properties were increased, the development of fiber properties was different in LC- and HC-refining. Fiber curl decreased in LC-refining but increased in HC-refining. LC-refining decreased fiber curl and increased tensile index simultaneously in this study. It is therefore likely that the decreased fiber curl contributes to the increase of tensile index in LC-refining. Furthermore, fiber wall thickness decreased and external fibrillation increased in HC-refining, while these properties were only slightly influenced in the LC-refining. Fibrillation was found to decrease in most cases for LC-refining while fiber wall thickness index increased slightly but consistently, which might indicate a less dense structure of the fiber wall or its surface layers.
Double-disc HC-refining with the same energy input as in a conical single-disc refiner resulted in fibers of higher external fibrillation, lower fiber wall thickness and higher fiber curl at a given fiber length.
The results indicate that analyzing individual fiber dimensions could be a better tool for understanding how fibers develop in different kinds of refining than analyzing conventional handsheet properties.
BIN, Disintegration, Fiber curl, Fiber dimensions, Fiber wall thickness, Fiber width, Fibrillation, HC-refining, LC refining, Mechanical pulp, Sheet properties, TMP
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PDF Document N2012-27-05-p860-871-Ferritsius.pdf (1314KB)
Development of TMP fibers in LC- and HC- refining (2012-27-05-p860-871-Ferritsius.pdf)