Morphology and metallurgical behavior of coke at tuyere of blast furnace
LÜ Qing-qing1,2, ZHOU Jun-lan3, WANG Guang-hui1,2, DU Ping3, TIAN Yong-sheng1,2
1. School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, Hubei, China; 2. Key Laboratory of Hubei Province for Coal Conversion and New Carbon Materials, Wuhan 430081, Hubei, China; 3. Iron Making and Environment Research Office, Iron and Steel Research Institute of Shasteel, Zhangjiagang 215625, Jiangsu, China
Abstract:To study the coke deterioration process in the tuyere area, two coke samples were obtained from the edge of the tuyere and the tuyere area. The morphology and products of the reaction interface between coke matrix and oxidizing gas, slag and iron were detected by microspectrophotometer and scanning electronic microscope. The metallurgical behavior of coke in the tuyere zone was analyzed. The results show that oxidizing gas erodes the coke structure by consuming carbon matrix. Slag disintegrates coke by reaction, eroding and extruding gas coke pore walls. The hot metal at the edge of the tuyere area erodes coke mainly through carburization. The residual ash covers the surfaces of the pore wall, which may hinder the chemical reaction with slag and liquid iron. The disintegrated coke was highly graphitized, showing a flake graphite structure. The change of microstructure leads to the reduction of coke strength and finally disintegrated and powdered. After the coke disintegrates, the internal ash and slag powder mixes with the slag and finally forms the final slag.
吕青青, 周俊兰, 王光辉, 杜屏, 田永胜. 高炉风口焦炭的形貌与冶金行为[J]. 钢铁, 2021, 56(10): 45-53.
LÜ Qing-qing, ZHOU Jun-lan, WANG Guang-hui, DU Ping, TIAN Yong-sheng. Morphology and metallurgical behavior of coke at tuyere of blast furnace[J]. Iron and Steel, 2021, 56(10): 45-53.
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