Decarbonizing rotary kiln–induction furnace based sponge iron production

The direct carbon dioxide (CO2) emissions from the iron and steel sector are nearly 7 % of the global CO2 emissions from energy use. India is the world's second-largest producer of steel and the largest sponge iron producer. India produces one-third of the global sponge iron, mostly from rotary kilns using coal as an energy source, resulting in higher energy and emission intensities than the global average. This study evaluates major options for CO2 abatement in the rotary kiln–induction furnace process for steel production. Based on the mass and energy balances of a typical sponge iron plant, this study evaluates the techno-economic potential of nine major decarbonization measures. The proposed decarbonization measures include improved energy efficiency, improved material efficiency, renewable energy use, and fuel substitution. Marginal abatement and green premium curves are generated by incorporating the dependency of different measures. Depending upon the set of options chosen, carbon abatement is in the range of 55.8 %–99.2 %. It is observed that 11.5 %–20.6 % of decarbonization potential can be achieved without any additional cost to the customer. These findings are insightful for policymakers and industry stakeholders and provide a foundation for designing and implementing a net-zero pathway for the sector.