<p>The blast furnace (BF) process is highly dynamic in nature due to wide variations in raw material properties as well as process conditions. These variations affect thermal conditions of the furnace, controlling which is a major challenge for operators. While lower fuel adjustment carries the potential of BF chilling and long outages, the excess fuel input can otherwise lead to deviations in hot metal chemistry followed by rejection by downstream customers. To mitigate these process nuances, the present paper relates to a method and system where a structured heat and mass balance approach is adopted considering thermodynamics behind BF start-up. Moreover, different scenarios have been built so that with varying conditions, the desirable extra coke required for replenishment of thermal state can be computed for sustenance in hot metal quality in terms of hot metal Si content. This has led to the avoidance of hot metal rejection and coke rate savings of 5&#xa0;kg/thm and CO₂ reduction post-implementation of the system.</p> Graphical Abstract <p></p>