Investigating the impact of pre-heating and stamping processes on metallurgical coke reactivity and strength

Coke plays a crucial role in the iron metallurgical process, as the efficient operation of a blast furnace requires high-quality coke. The stamp‑charging method of coke production has proven superior to the conventional top‑charging method, as it improves coke quality and allows for a higher ratio of non-coking coal. In this study, the quality of coke produced by three different methods was examined. The preheating and stamp‑charging method, which involves heating the coal blend to the tarrification point before stamping, showed a significant enhancement in coke quality. During pre-heating, the oil and tar within the coal act as a self-binder, leading to denser coal charging. The results demonstrated that hot stamping generally improved both coke strength and coke reactivity behavior compared with conventional charging techniques, although the extent of improvement strongly depended on coal blend quality. Two-way ANOVA analysis revealed that coal blend composition predominantly governed CRI behavior, whereas charging methodology exerted comparatively stronger influence on CSR development through enhanced bulk density and coke matrix consolidation. The study highlights the importance of simultaneously optimizing coal blend quality and charging methodology to maximize the utilization of non-coking coal with minimal adverse impact on metallurgical coke quality.