Drone image of the month: It’s all in the mix
- What does it show?
We are at the top of the production chain of the integrated steel mill of thyssenkrupp Steel. The view encompasses one of a total of six adjacent fine ore blending yards at the Duisburg-Schwelgern location. A so-called ‘stacker’ moves the bed on rails to fill it with raw materials for sintering.
- What is the purpose of a fine ore blending yard?
Before steel production, pig iron is produced in the blast furnace. This requires iron ore, coke, and other additives, which must be sorted and prepared accordingly. While coarser raw materials are suitable for immediate use in blast furnaces, finer material is first transported to the blending yards where it is mixed with other fine ores, fuels, and additives to form a homogeneous mixer ore of consistent quality.
- And what is the stacker used for?
Blending yards are built up in layers. The stacker ensures that the individual raw materials are ‘stacked’ one after the other in regular layers as well as in the longitudinal direction. The device needs approx. 15 minutes for one trip. Each blending yard is about 390 meters long, about 13 meters wide, and will end up being up to 13 meters high. By the time this height is reached, the stacker will have completed up to 600 trips!
- What is the lifetime of a fine ore blending yard?
A full, freshly stacked blending yard comprises 140,000 tons of ore. As a rule, after four to five days all the material is used up for sintering or pig iron production. As soon as one of the blending yards is empty, another one is ‘cut,’ and the empty blending yard is stacked again. This is why there are a total of six such blending yards on site: While two are being filled up in parallel, two can be emptied. The remaining two blending yards serve as buffers.