DEM study of particle segregation in the throat region of a blast furnace

Particle segregation in the throat region of iron-making blast furnaces (BFs) is an important issue, as the non-uniformity of burden materials due to segregation in the radial and vertical directions in this region may affect the gas distribution, heat and mass transfers, and chemical reactions inside BFs. Therefore, it is important to understand the fundamentals of particle segregation in the throat region for stable and efficient BF operations. In this work, particle segregation near the furnace top is studied at particle scale in basic terms and the effects of several key variables on particle segregation are investigated including particle size ratio and sliding friction coefficient using DEM simulations under full-scale conditions. The results show that particle size ratio plays a very important role in segregations along both radial and vertical directions, while the sliding friction coefficient has insignificant effect on these segregations. Moreover, the mixed layer of coke and ore particles is also captured in this work. This study provides useful microscopic information for optimizing burden distribution in ironmaking BFs.