Novel blast furnace operation process involving charging with low-titanium vanadium–titanium magnetite carbon composite hot briquette

An innovative process of blast furnace (BF) operation involving charging with low-titanium vanadium–titanium magnetite carbon composite hot briquette (LVTM-CCB) was proposed for utilizing LVTM and conserving energy. In this study, the effect of LVTM-CCB charging ratio on the softening, melting, and dripping behaviors of the mixed burden was explored systemically, and the migration of valuable elements V and Cr was extensively investigated. The results show that with increasing LVTM-CCB charging ratio, the softening interval T₄₀-T₄ increases from 146.1℃ to 266.1℃, and the melting interval T_D-T_S first decreases from 137.2℃ to 129.5℃ and then increases from 129.5℃ to 133.2℃. Moreover, the cohesive zone becomes narrower and then wider, and its location shifts slightly downward. In addition, the recovery ratios of V and Cr in dripped iron first increase and then decrease, reaching maximum values of 14.552% and 28.163%, respectively, when the charging ratio is 25%. A proper LVTM-CCB charging ratio would improve the softening–melting behavior of the mixed burden; however, Ti(C,N) would be generated rapidly in slag when the charging ratio exceeds 25%, which is not favorable for BF operation. When considering the comprehensive softening–melting behavior of the mixed burden and the recovery ratios of V and Cr, the recommended LVTM-CCB charging ratio is 20%.