Effect of plasma irradiation on the fine particle behavior in a spouted bed

Abstract

The combination of a spouted bed with non-thermal plasma has been used widely in industrial chemical processes. However, the detailed behavior of particles in a spouted bed with irradiation of plasma is still unknown. In this study, a fluidization experiment of fine white fused alumina particles under the irradiation of a dielectric barrier discharge (DBD) plasma generator was performed, and the effect of the plasma irradiation on the particle behavior in a spouted bed was evaluated. Essential operation parameters, such as static bed height, gas velocity, applied voltage, and working gases were changed, and the minimum spouted velocity, pressure drop, bed void fraction and spouted bed temperature with plasma enhancement were measured to understand the fluidization behavior of fine particles. As the results, the minimum spouted velocity decreased as the applied voltage increased to a high voltage, irrespective of the initial static bed height, while the void fraction of the solid bed before the fluidization point increased with an increase in the applied voltage. Fluidization behavior varied with the working gas, and the minimum spouted velocity with N2 was much higher than that of Ar. The temperature of the bed and particle surface did not show apparent changes when the plasma was applied. The proposed mechanism shows that the ionization of gas improves the interaction between particles and may cause the minimum spouted velocity to decrease.