MgO对赤铁矿焙烧压团组成结构与强度的影响

Effect of MgO on Structure and Strength of Hematite Roasted Briquetting

在赤铁矿中添加MgO制备焙烧压团,利用矿相显微分析、扫描电镜分析、抗压强度检测和FactSage热力学计算相结合的方法,研究了MgO添加量对焙烧压团组成结构与抗压强度的影响机理。结果表明,随着MgO的增加,压团孔隙率降低较为明显;焙烧压团未氧化的磁铁矿含量升高,赤铁矿含量降低,且随着MgO添加量增加,焙烧压团具有很好的综合显微力学性能,在压团氧化焙烧过程中,应适当增加磁铁矿的含量,以增加压团抗压强度;当MgO添加量为2%和4%时,焙烧压团磁铁矿含量分别达到18.97%和24.16%,在不配加粘结剂的情况下,每个压团抗压强度可以达到1.924kN和1.993kN。

Calcined briquetting was prepared by adding MgO to hematite.Mechanism of effect of MgO addition on composition and compressive strength of roasting compaction was investigated with combination of ore phase microscopy,scanning electron microscopy,compressive strength testing,and FactSage thermodynamic calculations.The results show that porosity drops obviously with increase of MgO addition.Magnetite content in roasting briquetting rises and hematite content drops with increase of MgO content.The interwoven structure of hematite and magnetite has good comprehensive micromechanical properties.In oxidative roasting process,magnetite content should be raised appropriately to increase compressive strength of briquetting.When addition amount of MgO is 2% and 4%,magnetite content in calcined briquetting is 18.97% and 24.16% respectively,and compressive strength of every briquetting is 1.924 kN and 1.993 kN respectively without binder addition.