Critical Granular Size Impact on Softening and Melting Behaviors of Sinters: From the Viewpoints of the Competition between In-situ Liquid Generation and Holdup

抄録

Unraveling the critical granular size in various chemical processes involving granular materials, such as blast furnace ironmaking process, holds significant importance in optimizing production efficiency. This study focuses on investigating the critical granular size by employing six mono-sized sinter packed beds, which are reduced at elevated temperature up to 1400°C. Quantitative analysis reveals two distinct behaviors, inconsistent shrinkages between 1200–1350°C and size-dependent rates of pressure drops approaching their maximum values. These results highlight the presence of a critical granular size between 2 mm and 4 mm under present experimental conditions. To elucidate these findings, a hypothesis based on the competition between the active role of liquid generation and the passive role of liquid holdup is proposed, and the strategies for utilizing the small particles below the critical size in binary-sized beds are given full discussions. This work aims to provide laboratory-scale experimental insights into the critical granular size effect and will shed light on exploring the critical granular size in industrial-scale processes involving granular materials in the future.