SINOPSIS

An experimental study is conducted on a gas-particle stirred ladle system with throughflow of molten metal using a simplified water model. A real-time image processing technique is employed to investigate the effects of nozzle location, throughflow rate and air and particle flow rates on the melt-particle mixing as well as to determine the timewise variation of gas and particle behavior. It is disclosed that the mixing energy supplied to the ladle consists of four sources including buoyancy, gas and particle injections and throughflow and that the mixing time decreases with an increase in the total mixing energy. No effect of nozzle depth on mixing appears explicitly if mixing times measured are summarized as a function of the total mixing energy. Longer mixing time is attained in the lower mixing energy regime, in which the main contribution is due to the rising gas bubbles through the melt driven by buoyancy. On the contrary, shorter mixing time is expected if the mixing energy input is larger and depends mainly on gas and particle injections. Correlation equations are derived to predict the mixing time in a gas-particle stirred ladle with throughflow.