(515a) Numerical and Experimental Analysis of Heat Transfer in a Continuous Spouted Bed with Particle Bottom Feed

Spouted beds are largely used due to their high heat and mass transfer rates and good mixing of solids. Specially, spouted beds are applied to deal with large particles (dp > 1mm), where fluidized beds are not efficient. In the literature there are several experimental and simulation studies using batch spouted beds. However, little information can be found regarding continuous spouted beds. The continuous operation has some important advantages such as higher production capacity and lower operating costs. The objective of this work is to perform numerical simulations and experimental analysis of heat transfer in a continuous spouted bed with particle bottom feed. To perform this analysis, experiments using glass beds as a particulate phase were carried out. The air inlet velocity and temperature were set to 20m/s and 80ºC respectively. During the experiments, the air temperature (central channel and annulus) and the particulate phase temperature (inlet and outlet) were measured. The average particle diameter and the particle density were 0.0039m and 2500kg/m3, respectively. The Eulerian-Eulerian multi-fluid modeling approach was applied to predict the gas-solid flow behavior, and the energy balance of each phase was solved to account for the heat transfer. The commercially available FLUENT 6.3 Computational Fluid Dynamics (CFD) code was used to perform the numerical simulations. The effective thermal conductivity of the particulate phase was considered to be a function of the particle concentration and it was added using a compiled executable code by means of a User Defined Function. The simulation results of air temperature (central channel and annulus) and solids temperature (inlet and outlet) showed a good agreement with the experimental data.