Experimental study of the effect of gas injection parameters on the bath mixing intensity induced during steelmaking

Abstract

The present study is concerned with the evaluation of the bath‐mixing intensity induced by gas injection during steelmaking. The rate constant for the process of mass transfer between the two cold‐model simulated immiscible liquids (water/oil) is employed as the criterion of judgement of bath‐mixing intensity. Gas is either injected from the bottom alone or simultaneously from top and bottom. Bath‐mixing criterion is successfully correlated with the mixing power. Increase in bottom injection rate is found to increase the rate constant. In the simultaneous injection lance distance, and top and bottom gas‐injection rates are shown to be the relevent independent dynamic parameters. From the comparison of the rate constants between pure bottom and simultaneous injection and pure top and simultaneous injection, it is asserted that the simultaneous injection provides more operational flexibility, better control of slag formation and refining rates as per blow requirements and steel grades. However, some minimum gas is required to realize the operational benefits.