Action rules of H-2 and CO in gas-based direct reduction of iron ore pellets

作者：Yi Ling-yun; Huang Zhu-cheng^*; Peng Hu; Jiang Tao

来源：Journal of Central South University (English Edition), 2012, 19(8): 2291-2296.

DOI：10.1007/s11771-012-1274-0

• iron ore pellets
• coal gas
• gas-based direct reduction
• reduction kinetics
• gas utilization

The gas-based direct reduction of iron ore pellets was carried out by simulating the typical gas composition in coal gasification process, Midrex and Hyl-III processes. The influences of gas composition and temperature on reduction were studied. Results show that the increasing of H-2 proportion is helpful to improve the reduction rate. However, when phi(H-2):phi(CO)> 1.6:1, changes of H-2 content have little influence on it. Appropriate reduction temperature is about 950 A degrees C, and higher temperature (1 000 A degrees C) may unfavorably slow the reduction rate. From the kinetics analysis at 950 A degrees C, the most part of reduction course is likely controlled by interfacial chemical reaction mechanism and in the final stage controlled by a combined effect of gaseous diffusion and interfacial chemical reaction mechanisms. From the utilizations study of different reducing gases at 950 A degrees C, the key step in reduction course is the 3rd stage (FeO -> Fe), and the utilization of reducing gas increases with the rise of H-2 proportion.

• 出版日期2012-8
• 单位中南大学