CFD-DEM Investigation on Pressure Drops of Heterogeneous Alternative-Layer Particle Beds for Low-Carbon Operating Blast Furnaces

Abstract

Low-carbon operation technologies of the blast furnace (BF) are crucial for reducing carbon dioxide emissions from the steelmaking industry. The variation characteristic of permeability and structure in a BF lumpy zone has a critical impact on achieving low-carbon operations. Still, their influences have not been fully understood, and related studies are very limited. To solve the problem of the deteriorating permeability of blast furnaces after lowering the coke ratio, this study aims to provide insights into the pressure drop of the lumpy zone in an ironmaking BF based on computational fluid dynamics coupled with the discrete element method (CFD-DEM) model. The study systematically investigates the influence of different packing configurations on permeability using a heterogeneous alternating-layer (HAL) packed bed. After the model was validated by comparing the simulation’s results with ones calculated by the Ergun equation, it was used to investigate the effects of the number of layers, coke-mixing ratio, nut coke replacement ratio, and particle-size ratio on the structure, void fraction variation, and pressure drop of the HAL packed bed. The results reveal the effect of these factors on the permeability of the lumpy zone, providing fundamental guidance towards low-carbon operations of BFs.