Research On The Optimization Of Smelting Process With Low Grade Iron Ore In Blast Furnace

With the iron and steel industry into the era of meager profit, more and more iron andsteel enterprises are smelting the low grade ore gradually. the paper make research onlow-grade iron ore smelting in Xinyu Iron and Steel Group, which mainly containsreasonable structure of raw fuels、 upper and lower adjusting system and intensifiedsmelting.At last,we get some conclusion.(1) After optimizing the structure of the original fuel, especially improving the qualityof coke, the adverse effect of the large amount of slag from low-grade iron and some poorproperty of metallurgical properties has been overcome well.By usingSinter5,which metallurgical properties are very good of, adding pellets and lump ores ofJinggangshan suitably, increasing the amount of6m coke, optimizing the ratio of4.3m cokeand Xinchangnan coke,blast furnace permeability has greatly improved, and permeabilityindex up to37.(2) After smelting with the low grade ore,the indexs on blast furnace have improvedgreatly by adjusting upper and lower system,which is based on the optimization of burdenstructure. After ore batch increases to68t,the amount of ore at the4th gear increases tworing, the length of the raceway prolongs to1.12～1.14m,the actual iron production in24hours has been up to6535t, and the fuel ratio has dropped to515kg/t.(3) Some intensified smelting measures have been adopted after optimizing themain parameters, which got Some achievement.However,compared to the high grade ore,thedegree of intensified smelting should weakened,especial Coal ratio.At the top pressure220kPa, Coal ratio150kg/t, Rate of oxygen4.25%, the fuel ratio has dropped to502kg/t and theactual iron production in24hours has been up to6625t.(4) When the raw material ratio of15%pellets+5%Jing gang shan lump ore+80%Sinter5, the coke ratio of70%6m coke+10%4.3m coke+20%Xinchangnan coke, fuel ratio502kg/t and the actual iron production in24hours6625t have got at blast furnace10ofXinyu Iron and Steel Group by adjusting upper and lower system and adroping someintensified smelting measures.