Effects of gas injection condition on mixing efficiency in the ladle refining process

The aim of this research was to investigate the effects of injection condition on the mixing efficiency of the gas injection treatment of the ladle refining process in steelmaking. A water modeling approach was employed. A NaCl solution was injected into the vessel and the electric conductivity value of the water solution was measured to represent the concentration of the additive. The results of this investigation reveal that up to a certain level, mixing efficiency is improved as the gas flow rate increases. Off-center injection is better than centerline injection. However, the injection lance should not be too close to the wall. Also, mixing efficiency is improved when the submerged depth of the immersion lance increases. The immersion hood has a optimal size as far as mixing efficiency is concerned. A larger or smaller hood would reduce its efficiency. The submerged depth of the immersion hood should be kept to a minimum to improve mixing efficiency.