低钛烧结矿还原粉化机理研究

国内某厂生产的低钛烧结矿可用于2 500 m3高炉冶炼,强度指标达到普通烧结矿水平,但其低温还原粉化率仍比普通烧结矿高40%以上,还原粉化机理尚不明确。通过分段测试低钛烧结矿的还原粉化率并进行矿相分析,结果发现:低钛烧结矿中的赤铁矿-气孔结构是产生裂纹的源头,铁酸钙熔蚀结构是主要粘结相,但此结构中有许多细小裂纹,裂纹沿程存在许多赤铁矿晶粒,其还原速率较快且易形成交叉网状裂纹,使粘结相结构受到严重破坏,致使烧结矿还原粉化性能差。

Research on Reduction Degradation Mechanism of Low Titanium Sinter

A kind of low-Ti-sinter produced in a domestic plant can be used for 2500m3 blast furnace smelting,the strength index is up to ordinary sinter level,but its low temperature reduction degradation index is 40% higher than ordinary sinter,the reduction degradation mechanism of low titanium sinter is still not clear.Low temperature reduction property of low-Ti-sinter was tested in several stages,and the microstructure in each stage was analyzed.The results show that,the hematite-pore structure in low-Ti-sinter is the source of crack,the calcium ferrite molten structure is the main binding phase,but there are many small cracks in this structure,along which there are a lot of hematite grains,the reduction rate is fast and cross reticular cracks are easy to form,the binding phase structure will be severely damaged,resulting in poor low temperature reduction degradation properties of sinter.