Modelling the mixing in an elliptic top submerged gas injected vessel
New iron-making technologies have been studied in the last two decades as alternatives to the iron blast furnace. The AusIron process uses a pair of top submerged lances to inject air into a molten bath of iron ore, slag and coal to produce pig iron. A study of the mixing behaviour in a water model of the AusIron process was carried out to determine the mixing characteristics to enable optimising the feed positions for the iron ore and coal. A series of stirred tank mixing model was proposed based on observations from dye tracer studies. The model was then fitted to thermal tracer results, which enabled the mixing pattern to be reproduced and studied. The lances were found to produce localised mixing. Mixing throughout the vessel was found to be effected through a shear layer lying between the two lances. The mixing model provides a means for studying the effects changing the values of different variables, such as gas flow rates and depth of lance immersion.