Direct reduction of carburized pre-reduced pellets by microwave heating
来源期刊：中南大学学报(英文版)2014年第1期
论文作者：胡兵 HUANG Zhu-cheng(黄柱成) YI Ling-yun(易凌云) JIANG Tao(姜涛)
文章页码：351 - 357
Key words：oxidized pellets; pre-reduction; carburizing; microwave heating; direct reduction
Abstract: A new iron-making process using carburized pre-reduced iron ore pellets and microwave heating is investigated. The pre-reduced pellets, with a porous structure, and fine particles are carburized homogeneously at 400-650 °C in a CO atmosphere. The carburized carbon not only acts reaction as a reduction agent, but also absorbs microwave in the reduction process. Hence, the carburized pre-reduced pellets can be rapidly reduced by microwave heating. There are three procedures involved in the process, namely, gas-based pre-reduction, low-temperature carburization and deep reduction by microwave heating. Carburized pre-reduced iron ore pellets show a rapid temperature rise that is twice as fast as the results for pre-reduced pellets in the laboratory. This not only improves the efficiency of the microwave heating, but also accelerates the reduction of iron oxides. The temperature of the pre-reduced pellets rises to 1050 °C in 45 min when the carburization rate is 2.02%, and the metallization rate and compressive strength reach 94.24% and 1725 N/pellet, respectively.
HU Bing(胡兵)1, 2, HUANG Zhu-cheng(黄柱成)1, YI Ling-yun(易凌云)1, JIANG Tao(姜涛)1
(1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. Zhongye Changtian International Engineering Co., Ltd., Changsha 410007, China)
Abstract:A new iron-making process using carburized pre-reduced iron ore pellets and microwave heating is investigated. The pre-reduced pellets, with a porous structure, and fine particles are carburized homogeneously at 400-650 °C in a CO atmosphere. The carburized carbon not only acts reaction as a reduction agent, but also absorbs microwave in the reduction process. Hence, the carburized pre-reduced pellets can be rapidly reduced by microwave heating. There are three procedures involved in the process, namely, gas-based pre-reduction, low-temperature carburization and deep reduction by microwave heating. Carburized pre-reduced iron ore pellets show a rapid temperature rise that is twice as fast as the results for pre-reduced pellets in the laboratory. This not only improves the efficiency of the microwave heating, but also accelerates the reduction of iron oxides. The temperature of the pre-reduced pellets rises to 1050 °C in 45 min when the carburization rate is 2.02%, and the metallization rate and compressive strength reach 94.24% and 1725 N/pellet, respectively.
Key words:oxidized pellets; pre-reduction; carburizing; microwave heating; direct reduction
