Investigation of the Reoxidation and Material Behavior ofDirectly Reduced Pellets and Fines Under Simulated RailTransport Conditions

European steel companies are endeavoring to switch to using directly reduced iron in steel production. Consequently, transporting directly reduced pellets, produced using reformed natural gas or hydrogen, by rail to various melting works will become increasingly important in the future. Alongside this change, it is essential that the metallization degree of the pellets does not decrease during transport, as it is important for further efficient processing, as well as safety reasons due to the exothermic nature of the oxidation reaction. This study compares the reoxidation behavior of industrially reduced pellets with that of H ₂-reduced pellets under simulated rail transport conditions on a laboratory scale. The fines of pellets were also examined to demonstrate the impact of increasing the specific surface area. Reoxidation tests were performed in defined container geometries to evaluate all possible conditions that could potentially affect the transported pellets. Analysis methods are based on visual assessment and recording of mass change over a defined period of time to accurately measure change in mass and metallization degree. The findings indicate that parameters such as particle size, oxidation conditions, environmental conditions, and container geometry during transport significantly influence the reoxidation behavior, with a pyramidal container design emerging as a promising wagon geometry.