Shoji Iwaoka

Stirring and its effect on aluminum deoxidation of steel in the ASEA-SKF furnace: Part I. Plant scale measurements and preliminary analysis

Simultaneous radioactive tracer dispersion and deoxidation measurements were taken in a 50 ton, electromagnetically stirred ASEA-SKF furnace. The tracer mixing studies were interpreted in terms of a one-dimensional dispersion model, by the “peak area method” and by the observation of the mixing time. The deoxidation measurements were interpreted by deducing the “deoxidation constant.” The measured eddy diffusivities ranged from about 100 to 300 cm2/s. and the circulation rates were of the order of 50 to 150 tons/min. The measurements indicate that the mixing characteristics of the system are not very much affected by power input (within the range studied), but the actual orientation of the electromagnetic field plays a major role. No direct correlation has been found between the rate of mixing and the deoxidation rate. It is suggested that a more sophisticated interpretation of the results through the use of turbulence theory would provide the desired relationship between mixing and deoxidation. Such work is in progress.