Abstract: Behavior of pre-reduction and final reduction of iron ore powder was investigated in a quartz fluidized bed reactor, and the effects of temperature and residence time of pre-reduction on the final reduction process were analyzed. Surface morphological properties of pre-reduction and final reduction products were observed and the effects of pre-reduction conditions on the final reduction were analyzed. The results indicate that temperature significantly influences the reduction rate and product structure. Pre-reduction degree increases with pre-reduction temperature, while there is some fluctuation in final reduction degree. Under the optimal pre-reduction temperature of 973 K, the final reduction degree is up to 80.4%. In addition, decrease of pre-reduction time is partly in favor of increase of the final reduction degree, but not for pre-reduction under certain conditions.

Key words: iron ore powder, fluidized bed, pre-reduction, final reduction

摘要： 在石英流化床中研究了铁矿粉的预还原和终还原行为，考察了预还原温度和时间对终还原过程的影响，通过对预还原和终还原产物表面形貌的观察，分析了预还原条件对铁矿粉终还原的影响规律. 结果表明，温度对还原速率和产物层结构有重要影响，预还原度随还原温度提高而增加，但终还原度有波动，较理想的预还原温度为973 K，终还原度可达80.4%. 在一定条件下缩短预还原时间不利于铁矿粉预还原，但有利于终还原.

关键词: 铁矿粉, 流化床, 预还原, 终还原