A system dynamic modeling to evaluate fluidized bed dryers under tempering and recirculation strategies

Abstract

Grain drying control strategies aim for a rational energy use and a final product with low breakage levels. However, an experimental approach may be prohibitive due to the costs, scale, and theoretical complexity of this operation. The simulation environment is suitable to design equipment’s and plan operations strategies with low cost and high certainty. This work utilized system dynamics modelling to quantify the percentage of product breakage during drying in fluidized bed dryers under recirculation and tempering strategies. A sensitivity analysis of the model’s input parameters including different fractions of recirculation was performed, showing their effects on drying and post-drying product quality. Finally, we present optimizations from different objectives of drying operations. The recirculation strategy worked as an attenuator to the drying rates and combined with tempering strategy reached a minimum breakage level.

Changes in Moisture Desorption Rate of Shelled Corn Layers in a Low-Temperature Deep-Bed Drying Column

“…Grain drying is required when the MC of grain poses a threat to safe storage and transportation and is an inevitable component of grain processing, which includes production, storage, and utilization [3]. During grain drying, moisture is transferred from a whole grain to the air and the latent heat required to vaporize the moisture is supplied by the drying air [4]. Thus, drying is a simultaneous process of heat and mass transfer [5][6].…”