Aggregate materials procurement

Various aggregate materials such as limestone, gravel and olivine are required for slag formation and to lower the melting temperature in the blast furnaces.

Proper slag control is also of major importance to ensuring ideal furnace operation. The optimum ratio of acidic to alkaline slag components is achieved in part by introducing the previously mentioned aggregate materials.

The requirement for limestone is currently about 650,000 tons per year. ROGESA currently procures this demand from various suppliers in Germany and France.

The annual requirement of around 75,000 tons of gravel currently is acquired primarily from regional suppliers.

In addition, depending on the level of hot metal production, between 60,000 and 90,000 tons of olivine are procured annually as flux for the blast furnace slag.