Development of an axisymmetric population balance model for spray drying and validation against experimental data and CFD simulations

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• 作者：Mark Pinto^a ; Ian Kemp^b ; ^{ian.c.kemp@gsk.com" class="auth_mail} ; Sean Bermingham^a ; Thoralf Hartwig^b ; Ariane Bisten^b
• 关键词：Two-fluid nozzle ; Droplet size distribution ; Drying kinetics ; Crust formation ; Computational fluid dynamics ; Particle residence time
• 刊名：Chemical Engineering Research and Design
• 出版年：April, 2014
• 年：2014
• 卷：92
• 期：4
• 页码：619-634
• 全文大小：5122 K

文摘

An incremental model for spray drying, including a full droplet size distribution, has been implemented in a flowsheeting package incorporating tracking of distributed particle properties. Results were compared with expected trends based on standard theory and with results from a laboratory-scale spray dryer with a two-fluid nozzle for atomization. Predicted trends were as expected, with larger droplets giving substantially longer drying times and higher final moisture content. Predicted final moisture content was lower than measured values, as the very short residence times for fine particles were inadequately represented by first-order falling-rate drying kinetics. Dryer gas flow patterns were simulated by computational fluid dynamics. Calculated droplet residence times were much lower than for a plug-flow or fully mixed gas flow, because a high-velocity gas flow zone from the two-fluid atomizer persists down a substantial part of the dryer.