A Case Study of Sintering with Low Silica Iron Ore

The low-silica and low basicity sintering is an effective measure for improving iron grade of sinter and reducing the slag amount of ironmaking and steelmaking. Sintering of the mixture at basicity (1.9, 1.8, and 1.7) and SiO₂ content (5.0, 4.9, 4.8, 4.7, and 4.6) were conducted in a sintering pot, and the microstructures of typical sinters were taken into comparison in this work. Experimental results show that with the basicity decreases from 1.90 to 1.70, there is an obvious change in the tumbler strength index (TI) of sinter; SiO₂ content affects mainly on the yield, but to a lesser extent on the TI of sinter. At the basicity of 1.70 and SiO₂ content of 4.60%, the TI of sinter is 58.53% which is 5% lower than the sinter at basicity of 1.90 and SiO₂ content of 4.98%. At basicity of 1.80 and SiO₂ content of 4.60%, the sinter obtains a good performance (yield of 76.07% and TI of 60.09%), which is close to the indexes of sinter at relatively high-silica and high basicity ( basicity of 1.90 and SiO₂ content of 4.98%), indicating that low SiO₂ content and low basicity sintering can be implemented.