Coking coal:
Coking coal is a kind of bituminous coal with low volatile matter, medium caking property and strong caking property. Bituminous coal with high coalification degree and good coking property. Also known as main coking coal.
There are two kinds of coking coal. The first is dry ash-free volatile VDAF >: 10% ~ 28%, and the adhesion index g >；; 65, maximum thickness of colloidal layer, y≤25mm. The coking performance of this part of coal is particularly good, and qualified blast furnace coke can be produced independently. The other dry ash-free volatile vdaf >: 20% ~ 28%, and the adhesion index is g >；; 50 ~ 65, coking is more serious than the former. Coking coal is a typical coking coal with medium volatile matter and good cohesiveness, and can form colloid with good thermal stability when heated. Coke with large size, few cracks, high crushing strength and good wear resistance can be obtained when coking alone. However, the generated expansion pressure makes it difficult to push coke, so it is necessary to add gas coal and lean coal to improve the operating conditions and coke quality. In coking coal blending, coking coal can play the role of coke skeleton, reduce shrinkage stress, thus improving the mechanical strength of coke, and is a high-quality coking raw material.
Coke:
Coke is made of bituminous coal by high-temperature coking process, which is mainly used for blast furnace ironmaking and smelting of non-ferrous metals such as copper, lead and zinc, and plays the role of reducing agent, heating agent and material column skeleton.
Casting coke is a kind of coke specially used for cupola ironmaking. Casting coke is the main fuel for cupola ironmaking. Its function is to melt the burden, overheat the molten iron, support the column and maintain its good permeability. Therefore, cast coke should have the characteristics of large lump, low reactivity, small porosity, sufficient impact crushing strength, low ash content and low sulfur content.