【摘 要】
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It is well understood that the longevity of a blast furnace campaign is limited by the wear of its hearth.Carbon dissolution and erosion of carbon refractories by the flow of sub - saturated molten ir
【机 构】
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Centre for Simulation and Modeling of Particulate Systems,School of Materials Science and Engineerin
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It is well understood that the longevity of a blast furnace campaign is limited by the wear of its hearth.Carbon dissolution and erosion of carbon refractories by the flow of sub - saturated molten iron are in part,the causes for such hearth wear.As a measure to protect the hearth refractories.addition of titanium - bearing materials into the furnace has become a common procedure during the critical stages of a campaign.Colloids of Ti ( C,N) particles are formed near the cooler eroded regions within the hot metal bath due to reduced solubility of titanium which may promote the formation of a protective layer along the eroded hearth surface.As a step to gain a fundamental understanding of the titanium behavior in a blast furnace hearth,a steady - state 3D CFD model based on BlueScope Steel s Port Kembla No.5 Blast Furnace hearth was developed.In the simulation,the hearth flow and temperature field were solved and validated first.Then,the formation behavior of the solid TiC particles were modeled by solving the species transport combined with thermodynamics of key chemical reactions.The effects of a sitting and floating deadman states were investigated.It was found that in a sitting deadman,a high concentration of TiC particles were held up dynamically near the cooler regions of the hearth,in particular along the hearth bottom and corner steps.Almost no trace of TiC particle was found along the hearth surface in a floating deadman because the large volume of liquid flowing through the coke free zone enhances overall hearth mixing which increases the near surface temperature above the Fe - Ti - C equilibrium temperature.
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