赤磁混合铁精矿球团焙烧固结机理研究

Mechanism of Roasting and Agglomeration on the ellets Produced by Blended Iron Ore Fines of Hematite and Magnetite

综合运用光学显微镜和显微图像分析仪等测试仪器和手段，对不同预热和焙烧条件下，巴西赤铁精矿与云南省内磁铁精矿搭配使用时氧化球团的矿物组成、显微结构以及焙烧固结机理进行了重点研究。研究结果表明，无论是在预热阶段还是在焙烧阶段，由于磁铁矿氧化生成的新生Fe2O3活性较赤铁矿颗粒中的原生Fe2O3活性高，磁铁矿的存在能够促进颗粒间Fe2O3再结晶的形成。因此，在赤铁精矿中适量配加磁铁精矿生产氧化球团，有利于降低预热焙烧温度，提高球团矿质量。

By means of modern measuring instruments and experiment methods including optical microscope and micrograph analyzer, the paper lays emphasis to study the mineral phase composition, microstructure, mechanism of roasting and agglomeration corresponding to the pellets produced by blended iron ore fines of Brazil Hematite and Yunnan Magnetite under the different conditions of preheating and roasting. The results show that, whether in the preheating step or in the roasting step, the existence of magnetite could benefit to generate the recrystallized Fe2O3 since the activity of the Fe2 O3 phase newly -generated from the oxidization of magnetite is higher than that of Fe2O3 phase o- riginally existing in the grains of hematite. Thus, the rational addition of the magnetite into the hematite while producing the oxidized pellets is favorable to reduce the temperature of preheating and roasting, and improve the quality of the pellet products.