Future Scenarios for Reducing Emissions and Consumption in the Italian Steelmaking Industry

The amount of CO2 emissions, water and electricity consumption, and soil exploitation of the main steel production routes (integrated cycle, scrap recycling, and direct reduction) are analyzed applying three possible future scenarios: use of carbon capture and storage (CCS); use of green hydrogen in substitution of natural gas; use of biomethane. Using actual process data and theoretical assumptions, the emissions and consumptions of the whole steel production cycle (from the iron ore extraction to the final steel product) are computed, taking into account also the auxiliary sources of emissions (i.e., limestone calcination and gas compression). The assessment results have highlighted the huge energy requirements and soil exploitation related to the application of green hydrogen in the steelmaking cycle, despite its low CO2 emissions. On the contrary, the use of biomethane appears more attractive if combined with carbon capture and storage systems. Overall, the results of the assessment provide a starting point for understanding the current level of sustainability of steel production and allow the identification of the most promising and plausible scenario for the steel industry of the future and the possible criticalities of each.