Effect of novel intensification structure on drying of particulate materials in spouted beds

Abstract

Through the hot air-drying experiment, the differences in drying rate, unit energy consumption, and bed pressure drop of the conventional spouted bed (CSB), the spouted bed with an integral swirling blade nozzle (ISBN), the spouted bed with spherical longitudinal vortex generators (LVGs), and the integral multi-jet spout-fluidized bed (IMJSFB) were studied. The Weibull distribution function was introduced to fit the drying data, and the differences in moisture diffusion coefficient, scale parameters, and drying activation energy of the four types of spouted beds were further discussed. The drying performance parameters of the four types of spouted beds were comprehensively evaluated. The results show that, compared with the CSB, LVGs and IMJSFB reduce the activation energy of the drying process, while the ISBN increases the activation energy of the drying process. The IMJSFB shows more excellent performance in terms of drying rate, scale parameters, unit energy consumption, and bed pressure drop, with the highest comprehensive score. Compared with CSB, ISBN and LVGs, the IMJSFB is more suitable for drying wet particles. For the IMJSFB, there exists an optimal value of particle diameter (d = 2 mm) for the drying process, which makes the particle drying rate reach maximum.