2020 Volume 106 Issue 10 Pages 727-734
Gas injection has been widely used to enhance mass transfer and homogenization of temperature and composition of molten steel. In this paper, water model experiments for degassing were performed to investigate mass transfer at free surface in a gas-stirred vessel. Mass transfer coefficients in liquid phase were measured and the correlation with gas flow rate and liquid height were analyzed. A mass transfer model was constructed based on the Levich’s model assuming that a part of energy input by gas injection was consumed near the free surface. As a result, the following dimensionless correlation was obtained:
Sh＝23［d2／v ρ(hvϵ/d)3/4／σ］1/2Sc1/2
The present correlation agrees well with the mass transfer coefficients in liquid phase including previous data for water model systems and that of molten steel systems can be also approximately estimated.
