MODEL STUDY OF FLUID-FLOW PHENOMENA IN A BOTTOM BLOWN BATH IN THE PRESENCE OF REVERSE EMULSIFICATION

Model experiments were carried out to elucidate the behavior of rising bubbles and resultant liquid flow motion in a cylindrical bath agitat ed by central bottom gas injection. Emphasis was placed on the bubble and liquid flow characteristics in the presence of reverse emulsificat ion, i.e., the slag droplet formation in the lower metal layer. Silico ne oil and n-pentane were used as models for top slag and water was us ed as a model for molten metal. A thin top oily liquid layer was place d on a pool of water. Air was injected through a central single-hole b ottom nozzle. The bubble and liquid flow characteristics for the top s ilicone oil layer were modulated significantly from their respective c haracteristics in a water bath without a top oil layer. On the other h and, these two characteristics for the n-pentane layer were not influe nced by the top oil layer at all inspite of the occurrence of the reve rse emulsification. The difference of the bubble and liquid flow chara cteristics between the silicone oil and n-pentane layers can be explai ned by the fact that the fluid flow resistance at the silicone oil/wat er interface is much larger than that between the n-pentane/water inte rface.