Sulfur removal from sulphur containing iron ores

Purpose and goal:

Even if the transition from fossil-based iron and steel production to fossil-free steel production is expected to involve a shift from virgin raw materials to more scrap-based steel production, there will always be a need for new steel production from iron ore. In this project a thermal treatment method allowing to mine complex mineralisations with regards to elevated sulphur contents has been developed.

The project has identified important process parameters as well as mechanisms for efficient S removal as well as potential process parameters for thermal processing. Expected results and effects:

The project has identfied at what temperature full S removal occurs. Even the potential to treat flotation sand has been illustrated.

For Kaunis this result indicates that it is possible to treat the Sahavaara mineralisation and remove the containing sulphur. If traditional flotation route is chosen, the results also indicate that it is possible to treat the flotation sand in similar fashion. Hence, these results in combination give Kaunis several potential routes for further development of the Sahavaara mineralisation.

Approach and implementation:

The project has been carried out as a collaborative project between the project partners Swerim, LTU and Kaunis. Due to the Covid-19 situation, all project meetings have been forced into digital meetings. This has meant that some of the planned workshops have not be held as physical activities as originally planned

The work has been divided into 4 work packages. Within the various work packages, the focus has been to solve the specific challenges identified. Continuous meetings between the project parties have been held where results have been discussed and the next step been identified.