1992 Volume 78 Issue 3 Pages 415-422
In the steelmaking and some other metal refining processes, bottom gas blowing is a popular method. In these systems, gas is blown into high temperature liquid metal from the bottom of the vessel at a temperature lower than the liquid temperature. Therefore, heat transfer takes places between bubbles and liquid. The mechanism of the heat transfer and the effect of the heat transfer on the formation of bubbles and the rising characteristics of the bubbles were investigated using air and helium in water model. The temperature of the injected gas was about -110°C. Heat transfer between bubbles and liquid almost finished near the nozzle. Bubble expansion due to the heat transfer resulted in the gas holdup increase in the radial direction. In the field far from the nozzle, the bubble characteristics for cold gas injection was the same as that for ambient temperature gas injection at the same mass flow rate.