ROMI: Role of Magnesium in iron oxide pelletizing

Purpose and goal:

Primary iron sources are expected to continue to play a critical role in the transition towards a sustainable society during a foreseeable future. Iron ore pellets is one primary source that can be produced fossil-free with the Swedish ore base and that can be used in todays conventional, as well as in a future fossil- free, iron and steel production

The project investigated the possibility of using a complex iron ore with a naturally high Mg content in pelletization. The results show a strong correlation between magnesium origin and the following iron oxide oxidation behavior. Expected results and effects:

The studies carried out show a strong link between Mg and the oxidation processes. The results show that Magnesium´s mineral form in the material in combination with total element composition is of greater importance than the amount of Magnesium. A high content of Mg that is bound in gangue will not necessarily affect the magnetite lattice during the induration process and thus no obvious affects on product properties are to be found.

However, initially lattice-bound Mg leads to dissociation of hematite at higher temperatures and can affect product properties. Approach and implementation:

The project has been carried out in collaboration between the academic and industrial partner. A part of the material to be used was pre-processed by an external international party (not part of the project), which due to covid led to an initial delay in the project. Materials and primary analyzes were otherwise carried out at the industrial partner and was input to the project.

These were then further investigated by the academic party and was then analyzed jointly and the results were implemented when possible . The project set-up and implementation have proceeded accorded to plan.