Effect of Iron Carbon Agglomerates on Isothermal Reduction of Pellets with Different Reducibility

• Published in: Steel research international Vol. 93; no. 4
• Main Authors: Bao, Jiwei, Chu, Mansheng, Liu, Zhenggen, Han, Dong, Guo, Jun, Zhang, Lifeng
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.04.2022
• Subjects: Agglomerates; Carbon; Chemical reduction; coupling mechanisms; Gasification; Iron; iron carbon agglomerates; isothermal reduction; Mutual coupling; Pellets; Reactivity; reducibility
• ISSN: 1611-3683; 1869-344X
• DOI: 10.1002/srin.202100345

Effect of iron carbon agglomerates (ICA) on the reduction of iron‐bearing burden (pellet and sinter) is greatly important for blast furnace (BF) smelting. Herein, the effect of addition amount and reactivity of ICA on the reduction of pellets with different reducibility is studied, and coupling mechanism between reduction reaction of pellet and gasification reaction of ICA is revealed. The results show that as the addition amount of ICA‐1 increases from 0 to 25 mass%, the reduction degrees of pellet A (PA) with a lower reducibility and pellet B (PB) with a higher reducibility are improved from 40.09% and 46.57% to 46.37% and 52.66%, respectively. With the increase in the reactivity of ICA from 52.81% (ICA‐1) to 66.20% (ICA‐2), the reduction degrees of PA and PB are increased from 46.37% and 52.66% to 50.06% and 58.11%, respectively. Regardless of additional amount and reactivity of ICA, the promotion effect of ICA on the reduction of PB with a higher reducibility is more significant. The coupling mechanism is that the products of reduction reaction of pellet and the gasification reaction of ICA are reactants of each other, and the mutual coupling process between the two reactions occurs in a continuous cycle. There is a coupling effect between reduction reaction of pellets and gasification reaction of iron carbon agglomerates (ICA), CO generated by gasification reaction of highly reactive ICA can improve the reduction driving force of pellets. Mixing ICA among pellets can significantly promote reduction of pellets, which is of great significance for improving the efficiency of blast furnace smelting.