Modelling of fluid flows in the blast furnace trough

The purpose of this study was to investigate fluid flows in the blast furnace trough and furthermore extend the lifespan of the trough. For that purpose both physical and mathematical models were utilised. The effect of different flow controllers, both at the surface and at the bottom of the trough, on the flow behaviour in the trough was examined. Additionally, the effect of the height of the bath level on flow velocities was studied. Return flows, caused by the tapping stream, are responsible for the wear of the walls at the impact point. According to the model tests, the smaller the area of turbulent flow, the stronger the flow in the vicinity of the walls appears to be. Return flows can not totally be restrained by flow controllers. However, the turbulence can be diminished with longitudinal pads at the bottom of the trough. Bottom pads cause increasing bottom wear and reduction in the length of laminar area. Increasing the amount of consumable refractory mass in critical areas of the trough slightly increases flow velocity in the vicinity of the walls. According to the calculations, the amount of entrained slag can be reduced by reducing the height difference between the slag and iron ports, raising the height of the bath level and reducing the height of the opening under the skimmer.