MIXING TIME AND FLUID-FLOW PATTERN OF COMPOSITION ADJUSTMENT BY SEALED ARGON BUBBLING WITH LADLES OF LARGE HEIGHT DIAMETER RATIO

Based on a prototype installation, the mixing time and the fluid flow pattern of CAS (Composition Adjustment by Sealed argon bubbling) were studied by a water model analog simulation. The decisive criterion for this simulation was formulated as a dimensionless number Qmu/(D2sigma ) which can satisfactorily keep the physical similarity between model and prototype. The critical bottom blowing gas flowrate due to the exi stence of a slag baffle was defined and used to evaluate the reliabili ty of the simulation. It was found from the investigation that the flu id flow behaviour of CAS is significantly different from that of the c onventional ladle bottom-blow stirring. Comments on the design and ope ration of CAS were proposed. The optimization of CAS was recommended t o be conducting the operation with both eccentric bottom blowing and e ccentric slag baffle positioning by using ladles of large height/diame ter ratio.