Several types of coke are recognised according to their physical and chemical properties. Among these types, the blast furnace and foundry cokes are high-quality cokes. A further two types of quality coke are used, to a lesser extent, as a supplementary fuel in the production of pig iron – nut and pea.
Blast furnace coke
Blast furnace coke is used mainly as a reducing agent and a heat source in blast furnaces. It also acts as a carrier and filling material in which gas circulates through the blast furnace charge column.
| Blast furnace coke |
Grain size 25 - 90 mm |
| Blast furnace coke |
Grain size 40 - 90 mm |
| Blast furnace coke |
Grain size + 80 mm |
Foundry coke
In terms of its qualities, foundry coke is similar to the blast furnace variant. Foundry coke is currently not only used for cast iron production; it is also a highly sought-after fuel in the production of basalt-based insulation materials. Compared to blast furnace coke, foundry coke differs primarily in its higher rigidity and lower abrasion resistance. The comparably higher quality of foundry coke makes it suitable for the production of pig iron. On the other hand, blast furnace coke is not suitable for the smelting of cast metals without prior adjustments in the full range to the smelting technology.
| Foundry coke I |
Grain size +100 mm |
| Foundry coke II |
Grain size 70 - 130 mm |
| Foundry coke III |
Grain size 60 - 90 mm |