8th International Congress on Science and Technology of Ironmaking - ICSTI 2018

Coke quality plays an important role in the blast furnace process. The current coke quality parameters used in Tata Steel, IJmuiden are the I40, I10 and CSR. With the introduction of more different types of coals there is a need for a more detailed characterisation of the coke. Especially for the behaviour of coke in the lower parts of the blast furnace a parameter is lacking. Previous research indicated coke texture as a promising candidate. A project was setup aimed at identifying the value of coke texture as a coke quality parameter for the blast furnace. For this evaluation a set of coke types based on industrial blends were produced with a variation in coke texture, charge density and grain size of inertinite. The coke texture measurement was evaluated first. One manual and two automated coke texture measurement techniques were used and compared. After the coke texture was established a range of tests were performed with the different coke types. These included the standard coke parameters like strength, CSR and ash chemistry, but also porosity measurements, reactivity test under blast furnace conditions and dissolution tests. In the dissolution tests heat treated samples of all coke types were included. Of these heat treated samples the degree of graphitisation was measured. Conclusions on the suitability of coke texture as a coke performance indicator for the blast furnace can be drawn based on the results of the various tests. Some interesting conclusions can be drawn from the coke dissolution experiments with heat treated coke samples. And some interesting relations were found between the sulphur level and the final carbon content of the hot metal in the experiments.