Electric Arc Furnace Stirring: A Review

Thermodynamics and kinetics are affected by the stirring conditions. Higher-stirring intensities promote conditions closer to equilibrium and increase the mass-transfer coefficients. A major limitation of the conventional electric arc furnace (EAF) is the low velocities of liquid steel which result in very poor mixing conditions. The practical consequences are lower decarburization rates and lower melting rates. Herein, the forces that operate and promote the motion of liquid steel in a conventional EAF are reviewed in detail; buoyancy forces, momentum transfer by the oxygen jets, drag forces by CO bubbles are produced by decarburization and local electromagnetic forces at the electrode regions. It is shown in the short range and limited intensity of the previous forces. Bottom gas injection and electromagnetic stirring are the main methods that can induce forced convection in the EAF. The information available is summarized and analyzed to describe the results obtained at laboratory level and industrial scale using different stirring mechanisms. Finally, guidelines are provided in this review for further research on the basis of the limitations of the current results.