Mathematical Modeling of Drying in a New Concept of Silo-Dryer-Aerator and the Quality of Soybean Seeds (Glycine max (L.) Merrill)

Abstract

The aim of this study was to model and validate a new concept of a silo-dryer-aerator for the drying of soybean seeds and determine the quality of the seeds in function of the air temperatures in the drying. Soybeans with water contents of 17% (w.b.) were dried and stored in a silo-dryer-aerator system that was designed with a drying chamber and four independent storage cells in the air drying temperatures at 30, 40 and 50 °C in silo-dryer-aerator. The drying in the air temperature at 30 °C in the cell C1 the diffusion approximation model was the one that best fit the data, in the cell C2 the Newton model prevailed and in the cells C3 and C4 the Midilli model. In the drying with air temperature of 40 °C in the cell C1 the Page model was the one that better adjusted the data, whereas in the cell C2 the model of diffusion approximation determined the best fit, while in the cells C3 and C4 the Page model obtained better fit. In the drying with air temperature of 50 °C in the cells C1, C2, C3 and C4 the logarithm model was the one that best represented the fit of the data. The increase in the drying air temperature to 50 °C decreased the quality of soybeans seeds. In the upper and middle part of the cells there was an increase in electrical conductivity (140.02 μS/cm/g) and germination (53%) compared with the lower dryer position.

Investigation of the Effect of Duct Geometry on Drying Air Flow in Conventional Grain Dryers by Porous Media Approach

“…This process exposes the grain to high mechanical stresses that can cause cracks, fissures, and fractures because the grain surface lacks the plasticity or elasticity to support them. Mathematical models are used in drying analysis, as well as in the development and optimization of dryers to describe such phenomena [15][16]. For example, Nowak and Przystupa [17] presented an algorithm for the assessment of the efficiency of grain dryers by calculating energy rating indices including water vapor content, temperature, and dryer capacity.…”