Experimental Exploration of Slag Iron Retention Behavior in Blast Furnace Hearth
SHEN Zhiqiang
ZHANG Litong
SHI Baolai
ZHANG Wenzheng
Abstract：This study investigated the effects of slag components,coke bed characteristics,and unburned pulverized coal on slag retention rate and dripping rate,to clarify the chemical interaction mechanism at the high-temperature phase interface between slag and coke.The results showed that the retention rate decreased with increasing alkalinity,due to the increase in CaO content,decrease in slag viscosity,and improvement in fluidity caused by higher alkalinity.The liquidus temperature of slag increased with increasing alkalinity.The retention rate also decreased with increasing magnesium-to-aluminum ratio,as both MgO and CaO are basic oxides that can reduce slag viscosity.Furthermore,the magnesium-to-aluminum ratio positively correlated with the liquidus temperature and melting temperature.When the coke particle size increased from 10 to 20 mm,the porosity of the coke layer decreased,resistance increased,and the retention rate increased.Higher ash content on the surface of the carbon source decreased the alkalinity of slag,leading to an increase in the retention rate.When the content of unburned pulverized coal reached about 6%,the slag-iron retention rate reached a minimum of 8.6%,due to its dual role of supplementing iron C,improving fluidity,reducing coke layer porosity,and hindering slag-iron penetration.
Keywords：slagretention ratecoke layerdripping down
Publication Date：2025-08-20
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：6( 20-25 )