CAJ | 학술논문

采用光学显微镜、莱卡图像分析软件对低品位赤铁矿煤基直接还原产品中金属铁晶粒尺寸进行检测。利用Hillert晶粒长大动力学模型对低品位赤铁矿煤基直接还原过程中铁晶粒的长大行为进行研究。结果表明：在还原温度为1200℃、还原时间为5~120 min时，金属铁晶粒的生长速率常数k为1.155μm2/min；在1200℃时，球团还原过程中，金属铁晶粒的平均尺寸D(μm)与还原时间t(min)的关系式为D=exp(0.565ln T+0.072)。在还原时间为120 min时，还原球团金属铁晶粒的平均尺寸D(μm)与还原温度T(K)的关系式为D=exp(-8995845ln T+8.899)。在还原温度1000~1200℃范围内，还原球团的金属铁晶粒生长表观活化能为132.53 kJ/mol。
채용광학현미경、래잡도상분석연건대저품위적철광매기직접환원산품중금속철정립척촌진행검측。이용Hillert정립장대동역학모형대저품위적철광매기직접환원과정중철정립적장대행위진행연구。결과표명：재환원온도위1200℃、환원시간위5~120 min시，금속철정립적생장속솔상수k위1.155μm2/min；재1200℃시，구단환원과정중，금속철정립적평균척촌D(μm)여환원시간t(min)적관계식위D=exp(0.565ln T+0.072)。재환원시간위120 min시，환원구단금속철정립적평균척촌D(μm)여환원온도T(K)적관계식위D=exp(-8995845ln T+8.899)。재환원온도1000~1200℃범위내，환원구단적금속철정립생장표관활화능위132.53 kJ/mol。
The size of metal iron grain of low grade hematite during coal based direct reduction was tested using optical microscope and Leica image analysis software. The growth behavior of metal iron grain was investigated using Hillert grain growth dynamic model. The results show that the growth rate constant of metal iron grain is 1.155μm2/min when reduced at 1 200 ℃ for 5-120 min. The relationship between the average size of metal iron grain D(μm) and reduction time t(min) is D=exp(0.565ln T+0.072) at reduction temperature of 1 200 ℃. The relationship between the average size of metal iron grain D(μm) and reduction temperature T(K) is D=exp(-8 995 845ln T+8.899) when reduced for 120 min. The apparent activation energy of metal ferrous grain growth is 132.53 kJ/mol in a reduction temperature range from 1 000 ℃ to 1 200 ℃.