SIMULATION OF BURDEN CHARGING IN A BLAST-FURNACE EQUIPPED WITH A BELL-LESS TOP SYSTEM USING DISCRETE ELEMENT METHOD

摘要

To achieve a stable and efficient blast furnace operation it is important to have a controlled gas flow inside the furnace with a proper burden distribution, thus a strict control of the particulate material size distribution inside the charge is required to avoid generation of preferential paths of the gas through the burden. This work uses Discrete Element Method (DEM) to simulate raw material loading into a blast furnace equipped with a Bell Less Top (BLT) system. The simulations were based on a real operation of a steelmaking plant in Rio de Janeiro (Brazil). The simulations allowed for the evaluation of the contribution of the physical properties of the raw materials fed into the furnace such as size distribution, shape and density, as well as the effect of the rotating chute of the BLT system on the loading of coke and the metallic burden, which is constituted of sinter, lump iron ore and pellet particles. A post-processing tool was developed that allowed a qualitative and quantitative analysis of the DEM simulation results in terms of particle size and component segregation at the top of the blast furnace. As such, the work establishes the foundations of a methodology that allows optimization of the rotating chute algorithm as a function the burden properties.