Numerical study on the mixing process of hot desulfurization slag and converter steel slag

Abstract

Slag mixing technique is a process that eliminates the lumping phenomenon of slag and iron in desulfurization slag. This process is conducted by mixing the high-temperature converter slag and iron desulfurization slag. The slag crushing difficulty is remarkably reduced after mixing. This technique eliminates the lumping phenomenon in the iron desulfurization slag. A numerical model based on Eulerian multiphase flow was established for the mixing process. The model obtained the characteristics of the phase field distribution inside the slag tank. The slag expansion phenomenon was identical with experimental results. A simplified temperature dropping model of slag mixing process was established based on the principle of energy conservation. According to this simplified model, the time dependence of the chemical reaction rate and temperature was investigated. The simplified model built by multifactor regression method can effectively predict the chemical reaction rate and temperature change under the following conditions: converter slag with an initial mass of 4–12 t, an initial iron oxide content of 20%–40%, an iron desulfurization slag mixing volume of 1–5 t, and an iron desulfurization slag mass flow rate of 0.1–1 t/s. The simplified model provides basic physical parameters for post-processing while ensuring safe production.