Modelling coating quality in fluidised bed coating : spray model

Fluidised beds are widely used in industrial applications, for example the coating of particles. Most of the research done on this process concerns the modelling of the hydrodynamics and the mechanics of the three-phase system (solid, gas and liquid) in a fluidised bed reactor, but little research has been performed on developing a quality model of the coating process. A quality model should be able to predict the quality of the process in terms of coating thickness and uniformity and the occurrence of unwanted side-effects, including agglomeration, attrition and spray loss. Therefore, a new quality model was developed for the coating process in a top-spray fluidised bed. The first step in the development of the new model was the creation of an accurate spray model that describes the movement and the heat and mass transfer of the droplets in the coating process. As a first, qualitative, step in the identification of the spray model, a sensitivity analysis was carried out to verify the impact of different input variables on the output variables of the model.Fluidised beds are widely used in industrial applications, for example the coating of particles. Most of the research done on this process concerns the modelling of the hydrodynamics and the mechanics of the three-phase system (solid, gas and liquid) in a fluidised bed reactor, but little research has been performed on developing a quality model of the coating process. A quality model should be able to predict the quality of the process in terms of coating thickness and uniformity and the occurrence of unwanted side-effects, including agglomeration, attrition and spray loss. Therefore, a new quality model was developed for the coating process in a top-spray fluidised bed. The first step in the development of the new model was the creation of an accurate spray model that describes the movement and the heat and mass transfer of the droplets in the coating process. As a first, qualitative, step in the identification of the spray model, a sensitivity analysis was carried out to verify the impact of different input variables on the output variables of the model.C