Feed Pile Modelling in a Reducing Electric Furnace

Abstract

The Reducing Electric Furnace (REF) is a promising technology for the transition to hydrogen-based steelmaking, in which Direct Reduced Iron (DRI) is melted in a slag–metal bath, but feed material entry and feed pile formation remain poorly understood. This work develops a DEM-only three-phase framework for DRI–slag–metal interactions that captures drag, convective heat transfer, melting and cohesion, and proposes two alternative buoyancy formulations: an Archimedes model for a ‘wet’ pile with slag penetration and a hydrostatic model for a ‘dry’ pile without penetration. Results show that whether the pile floats or sinks in the slag is governed primarily by the assumed degree of slag penetration into the pile. In all cases, interaction with the metal phase is limited. Slag properties such as temperature, thermal conductivity, density and layer thickness dominate pile size, shape and melting, while slag viscosity and particle thermal properties play a secondary role. This work provides a foundational DEM-only model and first insights into feed pile behaviour in Electric Smelting Furnaces.