Influence of Coal Reactivity on Carbon Composite Briquette Reaction in Blast Furnace

In this research, using the carbon composite briquette (CCB) containing carbon: 20.30 wt%, Fe3O4: 29.70 wt%, FeO: 39.70 wt%, metallic iron: 1.57 wt%, and gangue: 8.73 wt%. the reaction behavior of the CCB in BF and the influence of coal reactivity was examined by the numerical investigation. Results showed that the development of the CCB reaction in BF was divided into six stages. The initial temperature of the CCB self-reduction was 850 K, the dominant temperature range in CCB reaction being effective for BF energy-saving was from 1000 K to 1150 K, its final reduction fraction, and final carbon conversion was 1.0 and 0.9, respectively. By decreasing the activation energy of coal gasification, the initial temperature of CCB self-reduction became lower, the effective temperature range of CCB reaction for BF energy-saving was wider, and the final carbon conversion increased, indicating to improve the coal reactivity in CCB could intensify the effect of its reaction on BF energy-saving. By increasing the activation energy of coal gasification, the initial temperature became higher, the effective temperature range of CCB reaction for BF energy-saving was narrower, and the final carbon conversion decreased, reflecting that to reduce coal reactivity in CCB could weaken the effect of its reaction on BF energy-saving.