In a journey of centuries, the ironmaking blast furnace has gone through many technological changes, which made it a fit-for-purpose till today. However, for the first time in history, its existence is being challenged by other iron making processes, due to its high carbon footprint compared to others. Many researchers are working on adapting the existing blast furnace process to meet the new challenges. Modelling has played a crucial role in new adaptations of the process. The present review has been dedicated to historical developments of blast furnace modelling. The models are broadly classified into comprehensive, zone-specific, and data-driven models. The comprehensive models are further classified into lumped models, 1-D, 2-D and 3-D steady state and transient models, and CFD-DEM models. For the purpose of brevity, the zone-specific models are exemplified by burden distribution models only. Finally, developments in data-driven models are discussed, before some general conclusions are presented.

In FY-20, India’s steel production was 109 MT, and it is the second-largest steel producer on the planet, after China. India’s per capita consumption of steel was around 75 kg, which has risen from 59 kg in FY-14. Despite the increase in consumption, it is much lower than the average global consumption of 230 kg. The per capita consumption of steel is one of the strongest indicators of economic development across the nation. Thus, India has an ambitious plan of increasing steel production to around 250 MT and per capita consumption to around 160 kg by the year 2030. Steel manufacturers in India can be classified based on production routes as (a) oxygen route (BF/BOF route) and (b) electric route (electric arc furnace and induction furnace). One of the major issues for manufacturers of both routes is the availability of raw materials such as iron ore, direct reduced iron (DRI), and scrap. To achieve the level of 250 MT, steel manufacturers have to focus on improving the current process and product scenario as well as on research and development activities. The challenge to stop global warming has forced the global steel industry to strongly cut its CO₂ emissions. In the case of India, this target will be extremely difficult by ruling in the production duplication planned by the year 2030. This work focuses on the recent developments of various processes and challenges associated with them. Possibilities and opportunities for improving the current processes such as top gas recycling, increasing pulverized coal injection, and hydrogenation as well as the implementation of new processes such as HIsarna and other CO₂-lean iron production technologies are discussed. In addition, the eventual transition to hydrogen ironmaking and “green” electricity in smelting are considered. By fast-acting improvements in current facilities and brave investments in new carbon-lean technologies, the CO₂ emissions of the Indian steel industry can peak and turn downward toward carbon-neutral production.

The Basic Oxygen Furnace (BOF) process is an exceedingly fast refining process needing a good dynamic model for better understanding and dynamic control. The process is characterised by reactions at multiple scales: at the scale of the metal bath and the slag and at the scales of droplets and bubbles. The reactions take place at multiple sites too. The presence of the supersonic jet interacting with the metal bath and the slag layer, producing various sizes of drops in the emulsion which on reaction produce copious bubbles at its interface, lime dissolution issues, etc., make the description of the dynamics of the process complex and fascinating. There are still areas where an adequate quantitative description needs further research.