Mineral Composition and Microstructure Changes of Iron Ore Sinter During the Gas-Solid Reduction

• Published in: 9th International Symposium on High-Temperature Metallurgical Processing pp. 817 - 825
• Main Authors: Zhao, Xia, Ma, Ze-jun, Yang, Yan-juan, Zhao, Yong, Pan, Wen
• Format: Book Chapter
• Language: English
• Published: Cham Springer International Publishing
• Series: The Minerals, Metals & Materials Series
• Subjects: Iron ore sinter; Mineral composition; Porosity; Reduction
• ISBN: 9783319721378; 3319721372
• ISSN: 2367-1181; 2367-1696
• DOI: 10.1007/978-3-319-72138-5_78

Characteristics of the gas-solid reduction reaction between iron ore sinter and carbon monoxide (CO) gas at 1273 K were studied with thermogravimetric analyzer. The microstructure, mineral compositions and porosity of sample were investigated prior to reduction, in the 30% reduced sample, in the 70% reduced sample, and in the fully reduced sample. At the reduction degree of 30%, the hematite and calcium ferrite was reduced to 44.4 and 60.4% respectively. At the reduction degree of 70%, all the hematite, calcium ferrite and magnetite were reduced to metal iron, only 36% wustite was left in the core area. The reduction reaction began with the loose structures and spread to the nearby area. In the area of micro-pores, the reducing gas can easily diffuse to the reaction interface to proceed the reduction reaction effectively. So increasing the content of micro-pores is an effective way to improve the reducibility of the sinter.