Numerical simulation of coke collapse and its optimization during burden charging at the top of bell-less blast furnace

Coke collapse is very important in blast furnaces as it determines the ore-to-coke ratio and further affects the gas utilization and CO2 emissions. Therefore, a three-dimensional model considering three types of ores and burden matrix charging of a bell-less top blast furnace is established using the discrete element method (DEM). The effects of reverse charging, coke platform width, central coke charging, and pellet ratio are investigated. The results show that reverse charging decreases the amount of coke collapse and improves the radial ore-to-coke distribution. A central coke charging as low as 5 wt% significantly reduces the coke collapse and improves the radial burden distribution. The platform width is recommended to be larger than 2 m with a pellet ratio no larger than 40% to improve the ore-to-coke ratio distribution. (C) 2021 Elsevier B.V. All rights reserved.