Abstract
In order to examine the effect of pulsating flow on the reduction kinetics, a single iron oxide pellet was reduced with hydrogen under pulsating flow in the temperature range of 500°C-1100°C and in the frequency range of 3.3-43.3 Hz. Three kinds of apparatus were employed to generate pulsating flow i.e. butterfly valve, rotary cock, and piston.
The rate of reduction was markedly accelerated by pulsating flow under the condition of a small flow rate of hydrogen.
After analysing the experimental results by the shrinking core model, it was found that the mass transfer coefficient in the gas film under pulsating flow was increased compared with that under steady flow.
The effect of pulsating flow on kinetic parameter such as mass transfer coefficient, intraparticle diffusivity and chemical reaction rate constant was also discussed.
