复合镁质添加剂对球团生产影响的试验分析

Analysis on effects of multiple MgO-bearing additive on pellet production

球团矿作为一种优质的高炉炼铁原料,其配比不断增加。试验采用复合镁质添加剂代替膨润土,提高球团矿中的MgO含量,考察其对生球质量和球团冶金性能的影响规律和作用机理。试验结果表明,采用复合镁质添加剂代替膨润土后,生球抗压强度略有降低,落下次数变化不大,爆裂温度均高于600℃;球团矿的低温还原粉化指数(RDI+3.15)变化不大,均高于92%,完全能够满足高炉冶炼要求;还原度和还原膨胀性能显著提高,MgO质量分数由0.2%增加到2.0%,球团矿还原度RI由67.58%增加至91.47%,还原膨胀指数RSI由23.51%降低至19.25%。为高炉优化炉料结构、进一步增加球团矿的配比提供支撑。

Pellet is one kind of iron-making raw material with high quality, and its proportion in the blast furnace charge is increasing gradually. Effects of multiple MgO-bearing additive replacing bentonite to improve MgO content in finished pellet on the pellet quality and metallurgy properties were investigated. The result indicated that after the replacement, the compression strength of green pellet decreased slightly, drop times changed little and bursting temperatures were all above 600 ℃, the low-temperature reduction disintegration index changed little and was all above 92% which could satisfy the requirement of blast furnace melting. The reduction degree and reduction expansion performance were significantly improved. The MgO content and reduction degree(RI) of the pellet increased from 0.2% to 2.0% and from 67.58% to 71.47%, respectively. The reduction expansion performance(RSI) decreased from 23.51% to 19.25%.