Optimization Of Two-strand Tundish Configuration And Impurity Removal By Mathematical Model

Tundish is an important reactor in the steelmaking process. Its function is not only depositing and distributing liquid steel, but also purifying liquid steel and removing non-metallic inclusions in it. This paper describes the mathematical simulation of flow field in tundish of NO.3 Steelmaking Plant of WISCO by using commercial software FLUENT and optimizing the structure of the tundish. Effect on steel flow in the tundish of bubble curtains is studied by mathematical simulation, and inclusion removal in the tundish is simulated. The factors affecting particle removal are analyzed, and mathematical model for calculating inclusion removal in the tundish is further improved.The fluid flow behavior of liquid steel in the tundish has been calculated with turbulence inhibitor, or turbulence inhibitor together with wires and dams tundish, which shows that a flow pattern favorable to the removal of tundish can be realized with proper located flow control devices in the tundish.The study on the bubble curtain tundish shows that gas injection from tundish bottom can form zonal gas curtain which breaks short-circuit flow, accelerates liquid steel mixture and is helpful for inclusion removal. The combination of turbulent inhibitor with bubble curtain can increase steel melt mixture. The technology is beneficial to effectively improving the feature of molten steel flow and prolonging residence time of molten steel, reducing the area of dead zone, improving inclusion removal. The gas blowing parameters have great effect on characteristic of liquid steel flowing, the gas volume fraction and inclusions removal rate. The study indicates it can have best result, when the appropriate gas blowing rate is 0.98m~3/h.The technology is also beneficial to effectively improving the feature of molten steel flow when turbulence inhibitor, wires, dams and gas curtain are adopted at the same time. But the molten steel's secondary pollution is likely to happen when the refractory melts.From the production of clean steel, energy-saving, and consumption-reducing point of view, this technique is effective and economic only when gas blowing quantity in the turbulence inhibitor tundish is 0.98m~3/h.