Influence Of MgO Distribution On Metallurgical Properties Of Blast Furnace Comprehensive Burdens

In recent years,with the steady development of economy,the blast furnace ironmaking industry has also made rapid development,both in terms of equipment conditions or quality of molten iron,ironmaking technology level and environmental protection have made great progress.At the same time,the development of the new process of ironmaking,the increase of the proportion of flux pellets into the blast furnace,and the change of raw material conditions also caused changes in the suitable MgO content and burden structure in the raw materials of the blast furnace.The suitable MgO content and the burden structure,on one hand,it can improve the desulphurization ability and slag iron separation ability of the blast furnace slag,ensure the smelting of the blast furnace.On the other hand,it also can improve the production and quality of molten iron and increase the economic benefits of enterprises.By studying the influence of MgO/Al₂O₃ on the metallurgical properties of sinter,it is found that when the basicity was controlled at 2.0,the carbon content was 4.1%,and the MgO/Al₂O₃ is in the range of 0.9 to 1.0,the metallurgical properties of sinter were better.Through the study of the consolidation mechanism of sinter,it is found that MgO has a higher melting point.With the increase of MgO/Al₂O₃,MgO will produce more high-melting point substances during the sintering process.For example:?Mg·Fe?O·Fe₂O₃,CaMgSiO₄,and Ca₃Mg?SiO₄?₂,et al,resulting in a decrease in the number of sintering liquid phase,which is not conducive to the improvement of sintering metallurgical properties.By studying the influence of MgO content on the metallurgical properties of magnesium flux pellets,it is found that when the basicity is controlled at 1.0,the roasting temperature is 1250°C,and the MgO content is 2.0%,the mechanical strength and roasting metallurgical properties of pellets are optimal.It meets the actual production requirements.Through the study of the roasting and cementing mechanism of magnesium flux pellets,it is found that with the increase of MgO content,the production of high melting point of MgFe₂O₄ is increased,resulting in a decrease in the amount of calcium ferrite production,which limits the improvement of metallurgical properties of pellets.By studying the influence of the MgO content and the burden structure on droplet performance of comprehensive burdens,it is found that when the MgO/Al₂O₃ of sinter is 1.0,the MgO content of flux pellets is 2.0%,and the blast furnace burden structure is 68%sinter+16%flux pellets+16%ore.The maximum pressure difference and the total characteristic value of the burden are small,and the droplet performance is optimal.Under these conditions,the fluctuation of pressure is smaller and dripping is more smoothly.Figure 56;Table 30;Reference 54.