Multi Zoned Dryers
Multi-zone dryers can provide independent and controlled drying rates while maintaining a straight and stable web at lengths up to 200 feet. Several polymeric coatings are dried by blowing jets of hot air on them from top and bottom sides in multi-zone dryers. The goal of removing solvent quickly from a coating by manipulating air flow and its temperature, together called operating conditions in this work, conflicts with the goal of producing blister-free coatings. Optimum operating conditions ensure minimum residual solvent and no defects. Determining optimum conditions for multi-zone dryers is a difficult task with severe convergence problems. Sometimes more than one solvent is used in the formulation of the coatings due to reduced cost and other benefits. Aim of the project is to determine optimum operating conditions for multi-zone dryers for multicomponent coatings using simple and rigorous methods.