Enhancing Electrochemical Reactions in Smelting and Refining Operations

摘要

Two techniques are described for the enhancement of the kinetics of reduction of iron oxide from slags by carbon in molten iron. Laboratory experiments have shown that the rate of iron oxide reduction by carbon saturated iron can be increased by 5 to 10 times when the reaction is carried out under a reduced pressure atmosphere. This effect is the result of the increased volumetric gas flow through the slag layer and the associated increase in slag stirring. A model is presented, which relates the mass transfer coefficient for ferrous ions in the slag to the ambient pressure. Additional laboratory experiments examined the electrochemical nature of iron oxide reduction from slag. Results indicate that the reduction of iron oxide from slag is increased in the presence of an applied electric field. The external circuit allows for the separation of the half-cell reactions associated with iron oxide reduction and decarborization and increases the reaction area available for the individual reactions. These results have significant implications for several important slag metal reactions, which occur during the different unit process steps of traditional integrated steelmaking, EAF based steelmaking, and future iron and steelmaking technologies.