Electric arc furnace slags
In the early nineties Arbed decided to replace the blast furnaces by electric arc furnaces which use mainly scrap iron as primary material for steelmaking. The fusion of scrap iron in the electric arc furnace results in a by-product, which has the dark grey aspect of an almost artificial color rock after cooling. This rock, with the designation electric arc furnace slag (EAF) possesses excellent chemical, physical and mechanical characteristics.
When the scrap iron fusion is completed, the liquid slags are evacuated from the furnace into an excavator bucket, led by means of special devices to the slag pits and poured in. After cooling, the slags are broken and put on stock before processing. The material then passes several crushers, i.e. drum- and gyratory crusher in order to be broken into aggregates of the dimensions requested by the customers. Finally, due to iron separation through electromagnets and screening in several stages the aggregates reach their final characteristics such as granulation, form and cleanliness index.