Fluidization Characteristic of Iron Powder at High Temperatures
1. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; 2. University of Science and Technology Beijing, Beijing 100083, China
Abstract:The fluidization characteristic and defluidization behavior of iron powder was investigated at higher temperature in a visual fluidized bed reactor. Influences of fluidizing gas velocity and particle size on defluidization temperature was studied. Results showed that the defluidization temperature increased with increasing fluidizing gas velocity and particle size. The minimum fluidization velocity at different temperatures was measured. Results showed that the minimum fluidization velocity increased with increasing temperature. The thermo-mechanical analysis indicated that the surface viscosity decreased with temperature, suggesting an increase of adhesion force between particles. Based on viscous flow theory, the mechanism of fluidization transition and defluidization was discussed.