白云鄂博铁球团矿异常还原膨胀的机理

Abnormal reduction swelling mechanisms of pellets from Bayan Obo iron ore

通过对比白云鄂博铁矿、精矿及还原前后球团矿的显微结构,对白云鄂博球团矿异常还原膨胀的机理进行研究。研究结果表明,球团矿气孔中挥发分的爆发扩大了基体裂块间的孔隙,加快了还原气体的扩散,增加了反应面积,使还原速度加快,从而导致了球团矿恶性膨胀。白云鄂博球团矿的“挥发分膨胀理论”是一种全新的理论,对抑制白云鄂博球团矿的恶性膨胀具有重要指导意义。

The abnormal reduction swelling mechanisms of pellets from Bayan Obo iron ore was investigated by comparing the microstructure of the iron ore,concentrates and pellets before and after reduction.The results showed that the outburst of volatiles in the pores of pellets increased the gap between the matrix grains,speeded up the diffusion of reducing gas,increased the reaction area,and accelerated the reduction speed,which resulted in the abnormal swelling of pellets.The"volatile swelling theory of Bayan Obo pellets"was a new theory,which had important guiding significance to restrain the abnormal swelling of the Bayan Obo pellet.