Exploring the Potential of Molten Carbonate Fuel Cells for CO ₂ Capture and Concentration: A Feasibility Analysis in the Steel Industry

This work investigates the use of molten carbonate fuel cells (MCFC) to capture and concentrate CO₂ emissions in the steel industry using real industrial data from Duferco Engineering S.p.A. Three main simulations were conducted to evaluate the feasibility of the MCFC unit in parallel with various configurations: oxy-combustion, CO₂ conversion, and liquefaction. The results indicate that for a furnace exhaust flow rate of 40,000 N m³/h, a MCFC unit, fueled with biomethane, with a size between 5.6 and 5.9 MW, is needed to have a zero CO₂ process. All scenarios achieve a CO₂ reduction greater than 100% thanks to the use of biomethane in the methane steam reformer. The various configurations were compared through the Total Energy Consumption Index (TEC index), which represents the overall energy demand for the CO₂ capture and treatment process per unit of captured CO₂. Among the configurations, oxy-combustion with cryogenic separation is the least energy-intensive (TEC: 4.7 MJ/kg), while methanation by electrolysis has the highest energy requirements (TEC: 7.3 MJ/kg). Furthermore, sensitivity analyses suggest that fossil methane can replace biomethane while still achieving at least 85% CO₂ reduction, highlighting the potential of MCFCs in CO₂ capture in the steel industry.