| In recent years, some blast furnace burden structures are changed due to the continuous improvement of iron ore price in our country. Due to use much more foreign mining in Nanjing Iron and Steel Corporation, the blast furnaces always run out of state because of larger changes of iron ore into BF. No.2 BF in new ironworks runs well after it start in Nanjing Iron and Steel Corporation in August 2006, utilization factor has remained at 2.5 t/m3·d around. But from April 2007, No.2 BF has rarely gone smoothly, utilization factor has reduced to 1.0t/m3·d. Aiming at this status, combining burden structure features of No.2 BF, systematicly research on metallurgical properties of high basic sinter , acid pellets and Australia natural lump ores , in a view to provide reference for burden structure optimization in No.2 BF. Main include:Low-temperature(500℃)reducing capabilities,High-temperature(900℃) reducing capabilities,High-temperature(900℃) reducing swelling capabilities and High-temperature softening and melting properties of burden charges. From experimental analysis, propose existing metallurgical performance deficiencies,and analyze the causes, try to find viable solutions. Also provide a reliable theoretical basis to the optimization of No.2 BF burden structure.Also how to guarantee slag viscosity at a reasonable level with the constant changes of BF iron ore, the former metallurgs get the slag composition by using the past experience or manual calculation, then know the slag viscosity through direct view of phase diagram, which they use to guide production practice. This process takes lots of work, also the phase diagram can not fully match the true slag ingredients, which always lead to a larger error. This paper address the issue, work out a software which can calculate the academic slag composition and other parameters of different ore composition and changing burden structure. Also collected a large quantity of slag viscosity test datas of normal production by experiment in Nanjing Iron and Steel Corporation, and the test temperature is 1500°C. Because of insufficient datas at the scene of slags, which are not able to explain the slag viscosity changes with the slag composition. Use chemical reagent preparation of simulated slags on the basis of original BF slags for more comprehensive measurement. Main components of average simulated slags preparation principle is the exception of FeO and sulfur (due to technical reasons not allocated income), the remaining slag ingredients are the same to the original BF slags. Through studying on a large number of BF slag components, we make some corresponding restriction to part of simulated slag composition and parameters.Build access data base which adapt to normal practice in Nanjing Iron and Steel Corporation. Under the construct principle of coordinate conversion, with the software of Excel working out industrial viscosity diagram of CaO-SiO2-Al2O3 system slag at 1500℃.Put the slag composition to the system, then we can take it as a tool to measure the slag whether meet the demand of normal practice or not.
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