Fluid Flow Characteristic of EAF Molten Steel with Different Bottom-Blowing Gas Flow Rate Distributions

As an efficient stirring method, bottom-blowing technology was applied in the present electric arc furnace (EAF) steelmaking process to improve the dynamic conditions of the molten steel. This article describes the development of a numerical model to simulate the 3D multiphase flows (gas, steel, and slag). Comparisons among uniform and non-uniform (linear and triangle distributions) bottom-blowing gas rate arrangements were performed with both metallurgic and dynamic parameters obtained from the numerical simulation process and separated liquid steel analysis. The numerical simulation results indicated that the bottom-blowing scheme with the gas rate in a linear change distribution had the best stirring effects in the molten bath. In addition, the dynamic conditions in the molten bath were worse when the bottom-blowing gas rate change was focused on the nozzle near the eccentric bottom tapping area. Furthermore, water model and industrial experiments were performed. For this purpose, 120 sets of heat industry data were collected in the 100 t EAF steelmaking process. The results showed that the non-uniform bottom-blowing scheme is more able to improve the dynamic conditions of the molten bath compared with the conventional uniform gas rate distribution, which further validated the reliability of the present numerical simulation results.