DRYING OF A PAPER COATING - EXPERIMENTAL-STUDY AND MODELING

This research deals with the physical mechanisms that occur during dry ing of a paper coating. A study at the local scale of the drying of a paper coating coupled with natural binder (starch) migrations is carri ed out. In this aim, drying experiments have been realized and lead to the determination of drying kinetics, time evolution of moisture cont ent profiles, and starch concentration distribution at the end of dryi ng. The results obtained allow the modelling to be validated. This mod el, which is based on diffusive liquid transport, takes into account t he shrinkage of the coating and the migration of the different solid c omponents during drying. It leads us to suggest that starch migration occurs until the coating is totally consolidated.