Study on the reducibility of iron ore pellets at high temperature
The behaviour of iron ore pellets in a blast furnace must be considered to improve ironmaking operations, especially when a large amount of the pellets is used. This study presents the reduction degree, mineralogical composition, and morphology of the pellet reduced in a gas mixture of 60% CO and 4...
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| Format: | Article |
| Language: | English |
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Vietnam Ministry of Science and Technology
2022-03-01
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| Series: | Vietnam Journal of Science, Technology and Engineering |
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| Online Access: | https://vietnamscience.vjst.vn/index.php/vjste/article/view/74 |
| _version_ | 1828047923690078208 |
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| author | Cao-Son Nguyen Thanh-Hoan Nguyen Son-Lam Nguyen Anh-Hoa Bui |
| author_facet | Cao-Son Nguyen Thanh-Hoan Nguyen Son-Lam Nguyen Anh-Hoa Bui |
| author_sort | Cao-Son Nguyen |
| collection | DOAJ |
| description |
The behaviour of iron ore pellets in a blast furnace must be considered to improve ironmaking operations, especially when a large amount of the pellets is used. This study presents the reduction degree, mineralogical composition, and morphology of the pellet reduced in a gas mixture of 60% CO and 40% Ar at temperatures between 900 and 1,100oC. The pellet was prepared from iron ore from the Cao Bang province, Vietnam, by rotary drum. The obtained results showed that the reduction degree of the pellet increased with increasing reduction time and temperature. The activation energy of the reducing reaction was calculated to be 63.2 kJ/mol, which indicated that reduction occurred more easily in the present condition. X-ray diffraction (XRD) results revealed mineralogical phases such as hematite (Fe2O3), magnetite (Fe3O4), wüstite (FeO), metallic iron (Fe), and fayalite (Fe2SiO4) existing in the pellets when reduced for different times and temperatures. Fe and Fe2SiO4 were found to be the majority in the pellet that was reduced for 90 min at 1,100oC. Scanning electron microscopy (SEM) observations suggested the formation of a liquid phase, e.g., Fe2SiO4, which retarded the reducing reaction because it hindered the diffusion of gas flow inside the pellet. This phenomenon is essential to blast furnace ironmaking because pellets must be completely reduced before they move down to the liquid zone.
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| first_indexed | 2024-04-10T18:49:30Z |
| format | Article |
| id | doaj.art-a41acf56d73c48bb9c74138b1147c7c3 |
| institution | Directory Open Access Journal |
| issn | 2525-2461 2615-9937 |
| language | English |
| last_indexed | 2024-04-10T18:49:30Z |
| publishDate | 2022-03-01 |
| publisher | Vietnam Ministry of Science and Technology |
| record_format | Article |
| series | Vietnam Journal of Science, Technology and Engineering |
| spelling | doaj.art-a41acf56d73c48bb9c74138b1147c7c32023-02-01T08:17:01ZengVietnam Ministry of Science and TechnologyVietnam Journal of Science, Technology and Engineering2525-24612615-99372022-03-0163410.31276/VJSTE.63(4).03-07Study on the reducibility of iron ore pellets at high temperatureCao-Son Nguyen0Thanh-Hoan Nguyen1Son-Lam Nguyen2Anh-Hoa Bui3School of Materials Science and Engineering, Hanoi University of Science and TechnologySchool of Materials Science and Engineering, Hanoi University of Science and TechnologySchool of Materials Science and Engineering, Hanoi University of Science and TechnologySchool of Materials Science and Engineering, Hanoi University of Science and Technology The behaviour of iron ore pellets in a blast furnace must be considered to improve ironmaking operations, especially when a large amount of the pellets is used. This study presents the reduction degree, mineralogical composition, and morphology of the pellet reduced in a gas mixture of 60% CO and 40% Ar at temperatures between 900 and 1,100oC. The pellet was prepared from iron ore from the Cao Bang province, Vietnam, by rotary drum. The obtained results showed that the reduction degree of the pellet increased with increasing reduction time and temperature. The activation energy of the reducing reaction was calculated to be 63.2 kJ/mol, which indicated that reduction occurred more easily in the present condition. X-ray diffraction (XRD) results revealed mineralogical phases such as hematite (Fe2O3), magnetite (Fe3O4), wüstite (FeO), metallic iron (Fe), and fayalite (Fe2SiO4) existing in the pellets when reduced for different times and temperatures. Fe and Fe2SiO4 were found to be the majority in the pellet that was reduced for 90 min at 1,100oC. Scanning electron microscopy (SEM) observations suggested the formation of a liquid phase, e.g., Fe2SiO4, which retarded the reducing reaction because it hindered the diffusion of gas flow inside the pellet. This phenomenon is essential to blast furnace ironmaking because pellets must be completely reduced before they move down to the liquid zone. https://vietnamscience.vjst.vn/index.php/vjste/article/view/74blast furnaceiron ore pelletmineralogymorphologyreduction degree |
| spellingShingle | Cao-Son Nguyen Thanh-Hoan Nguyen Son-Lam Nguyen Anh-Hoa Bui Study on the reducibility of iron ore pellets at high temperature Vietnam Journal of Science, Technology and Engineering blast furnace iron ore pellet mineralogy morphology reduction degree |
| title | Study on the reducibility of iron ore pellets at high temperature |
| title_full | Study on the reducibility of iron ore pellets at high temperature |
| title_fullStr | Study on the reducibility of iron ore pellets at high temperature |
| title_full_unstemmed | Study on the reducibility of iron ore pellets at high temperature |
| title_short | Study on the reducibility of iron ore pellets at high temperature |
| title_sort | study on the reducibility of iron ore pellets at high temperature |
| topic | blast furnace iron ore pellet mineralogy morphology reduction degree |
| url | https://vietnamscience.vjst.vn/index.php/vjste/article/view/74 |
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