Simulating Colloidal Thickening: Virtual Papermaking

Abstract

Paper is made by the continuous thickening of an aqueous suspension of cellulosic particles. In pub lished computer simulations, the interactions among cellulose fibers have mainly been considered the most relevant issue. However, colloidal particles are present in much larger numbers than cellulose fibers, and influence paper quality in different ways. In this study, we describe a new simulation proce dure for the interactions among fibers and fines, during the thickening process. Among the param eters involved in paper forming taken into consid eration are fiber and fine size distributions, fiber and fine concentration, fiber propensity to floccu late, and fiber flexibility, as well as parameters de scribing the process conditions, such as geometry of the filtering fabrics, drainage speed, turbulence intensity, and turbulence decay. Generated struc tures may be useful in interpreting physical pro cesses in the forming process, design of new mea suring instruments or estimation of product quality.

Keywords

Paper papermaking forming structure fibers fines colloidal

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