Two Phase Mass Transfer in Gas Stirred Reactors

Abstract

Gas stirred reactors are used in several metallurgical processes, such as the desulfurization of liquid cast iron, to increase the rate of the chemical reaction and homogenize the melt. Mixing times and two phase mass transfer rates were measured in a model system of a liquid steel ladle. Mixing times were increased by the presence of a second phase and were faster for off-center tuyeres. However, two phase mass transfer is faster for a center tuyere as compared to an off-center tuyere. The rate of mass transfer was independent of tuyere size, lance versus tuyere injection and only slightly dependent on the viscosity of the second phase. The dramatic increase in mass transfer at a critical flow rate is explained in terms of an increase in the interfacial area between the two phases.