A Review on Reduction Swelling and Degradation of Fluxed Pellets in China: Current Advances and Future Directions

Iron ore pellets have become an essential blast furnace burden component, offering significant advantages in energy conservation, emission reduction, cost efficiency, and productivity due to their high iron grade, excellent reducibility, low fuel consumption, and minimal environmental impact. However, in high‐proportion pellet operations, fluxed pellets are prone to reduction swelling and low‐temperature reduction degradation in the upper regions of the furnace which can lead to severe operational issues. Moreover, current understanding of their swelling and degradation mechanisms remains contradictory, hindering the wider application of this technology. Therefore, this article presents a comprehensive review of the reduction swelling and low‐temperature reduction degradation behaviors of fluxed pellets. The underlying mechanisms are elucidated by integrating recent global research progress, and the key factors influencing pellet swelling and degradation are systematically analyzed. Furthermore, control and optimization strategies adopted by steel enterprises are summarized, along with current technical challenges and prospective research directions. The ultimate aim is to propose practical measures to mitigate swelling and degradation in fluxed pellets, thus promoting high‐proportion pellet smelting in blast furnaces and contributing to the development of green, low‐carbon ironmaking technologies.