基于Energiron工艺,采用线性拟合、相关系数对比、扫描电镜能谱分析(SEM-EDS)等研究方法,考察酸性氧化球团矿在特定还原气氛下的气基还原过程。研究结果表明:反应过程可分为3个阶段,第1阶段(0~5 min)控速环节为界面化学反应,表观活化能为28.8 k J/mol;第2阶段(5~28 min)为界面化学反应和内扩散混合控速;第3阶段(28~34 min)控速环节为内扩散;同时得出不同温度下的有效扩散系数Deff和反应速率常数krea,拟合出krea与温度T的关系式;最后给出内扩散阻力和界面化学反应阻力随时间的变化趋势。
Based on Energiron process, the research methods of the linear fitting, the correlation coefficient comparing and scanning electron microscope and energy dispersive spectrometer (SEM-EDS) were used to investigate the gas-based reduction process of the acid oxidation pellets under the particular reducing atmosphere. The results show that the reaction process can be divided into three phases: the controlled speed link of first stage (0-5 rain) is the interracial chemical reaction of which the activation energy is 28.8 kJ/mol, the second stage (5-28 min) is the hybrid of interfacial chemical reaction and internal diffusion, and the controlled speed link of the third stage (28-34 mim) is internal diffusion. The effective diffusion coefficient Deft and the reaction rate constant drea at different temperatures are calculated at the same time. At last, the variation tendency of resistance of internal diffusion and interfacial with time are given.