Vol.55, No.1, 24 ~ 31, 2017
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Title |
Reduction Behaviors of Carbon Composite Iron Oxide Briquette Under Oxidation Atmosphere |
이기우 Ki-woo Lee , 김강민 Kang-min Kim , 권재홍 Jae-hong Kwon , 손상한 Sang-han Son , 한정환 Jeong-whan Han |
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Abstract |
The carbon composite iron oxide briquette (CCB) is considered a potential solution to the upcoming use of low grade iron resources in the ironmaking process. CCB is able to reduce raw material cost by enabling the use of low grade powdered iron ores and coal. Additionally, the fast reduction of iron oxides by direct contact with coal can be utilized. In this study, the reduction behaviors of CCB were investigated in the temperature range of 200-1200 ℃ under oxidizing atmosphere. Briquettes were prepared by mixing iron ore and coal in a weight ratio of 8:2. Then reduction experiments were carried out in a mixed gas atmosphere of N2, O2, and CO2. Compressive strength tests and quantitative analysis were performed by taking samples at each target temperature. In addition, the reduction degree depending on the reaction time was evaluated by off-gas analysis during the reduction test. It was found that the compressive strength and the metallization degree of the reduced briquettes increased with increases in the reaction temperature and holding time. However, it tended to decrease when the re-oxidation phenomenon was caused by injected oxygen. The degree of reduction reached a maximum value in 26 minutes. Therefore, the re-oxidation phenomenon becomes dominant after 26 minutes. (Received April 12, 2016; Accepted August 9, 2016) |
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Key Words |
iron oxide, reduction degree, SEM, strength, off-gas analysis |
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