Relationship between the technical parameters of cokes produced from blends of three Polish coals of different coking ability

The demand for metallurgical coke for blast furnaces is forcing the coking industry to look for new sources of coking coals. The physical and chemical parameters of coals used in coking blends determine the quality (reactivity and strength) of the finished cokes. This study examines the technical properties of the cokes produced from various blends of three Polish coals with different coking. These coals were collected from three mines: Zofiówka, Szczygłowice, and Krupiński (Upper Silesian Coal Basin, Poland). The coal charges were coked in the laboratory scale, at temperatures of up to 1000 °C, in an inert atmosphere. The coke reactivity (index CRI) and the coke strength after reaction (CSR) were measured and correlated to the properties of parent coals using statistical analysis. The result of this study shows strong relationships between the concentration of the best coking coal (Zofiówka) in the blend and the CRI and CSR of the resulting coke. The CRI and CSR parameters for cokes obtained from single coals and from their blends show the additive character. This study also confirms the linear relationship between CRI and CSR parameters of the cokes.