碱度对镁质低硅球团矿冶金性能的影响

Effect of alkalinity on metallurgical properties of magnesian low-silica pellets

为寻找镁质低硅球团矿最优碱度条件,提高球团矿的质量,本文通过对不同碱度下镁质低硅球团矿冶金性能的变化规律进行研究,并对不同碱度下球团矿的矿相结构、元素分布、孔径分布等进行分析,探讨碱度对球团矿综合冶金性能的影响机理,通过灰色关联度法确定球团矿综合性能最佳的碱度条件。结果表明:随着碱度的增加,球团矿的抗压强度、还原性和还原膨胀指数均先增加后降低,球团矿的抗压强度在碱度为0.40~0.80时相对较好,低温还原粉化性能逐渐劣化,熔化温度区间整体呈降低的趋势,料层最大压差和综合透气性指数均逐渐降低,这表明高碱度球团的软熔滴落性能优于低碱度球团。在试验条件下,碱度为0.60时球团矿的综合性能最佳。

In order to find the optimal alkalinity conditions of magnesian low-silica pellets and improve the quality of pellets, the influence mechanism of alkalinity on the comprehensive metallurgical performance of pellets is discussed by studying the variation law of the metallurgical properties of magnesian low-silicon pellets at different alkalinity levels, and the ore phase structure, element distribution and pore size distribution of pellets under different alkalinity levels are analyzed, while the best alkalinity conditions for the comprehensive performance of pellets are determined by the grey correlation degree method.The results show that the compressive strength, reducibility and reduction expansion index of pellets increase and then decrease with the increase of alkalinity, and the compressive strength of pellets is relatively good at 0.40~0.80,the low temperature reduction pulverization performance is gradually deteriorated, the melting temperature interval shows an overall decreasing trend, and the maximum pressure difference of the material layer and the integrated permeability index are both gradually decreased, which indicates that the soft melting drip performance of the high alkalinity pellets is better than that of the low alkalinity pellets.Under the test conditions, the overall performance of the pellets is best when the alkalinity is 0.60.