Process design and utilisation strategy for CO2 capture in flue gases. Technical assessment and preliminary economic approach for steel mills

• Published in: Renewable & sustainable energy reviews 2023-09, Vol.184, p.113537, Article 113537
• Main Authors: Navarro, J.C., Baena-Moreno, F.M., Centeno, M.A., Laguna, O.H., Almagro, J.F., Odriozola, J.A.
• Format: Article
• Language: English
• Subjects: CCU technology; CO2 methanation; CO2 valorisation; CO2–SO2 capture; Tecnoeconomic analysis
• ISSN: 1364-0321; 1879-0690
• DOI: 10.1016/j.rser.2023.113537

The steel industry is the most relevant sector in emerging economies due to its application in numerous fields. However, steel manufacturing involves large energy investment and produces significant greenhouse gas emissions. The current world economic and environmental scenario therefore necessitates that improvements in the footprint of the steel industry be made without affecting its viability. Considering the present challenge, we report two possible processes for Carbon Capture and Utilization (CCU). The first process is the competitive capture of CO2–SO2, followed by CO2 valorisation to methane. However, the CO2 capture capacity and lifetime for the adsorbent after multiple cycles could be improved through preliminary desulphurization of the gas current. The improved system demonstrates net profitability in a typical stainless steel plant. Therefore, it can be implemented in an industrial setting without profitability loss to steelmaking operations, fulfilling bot the goal of reducing CO2 emissions while protecting the mainstay of the plant. •High catalyst degradation for CO2 methanation under SO2 presence.•Improvement of the natural dolomite with the employment of slags as binders.•Competitive adsorption for CO2–SO2, with consequent degradation for the adsorbent.•Improvement of adsorbent lifetime with previous desulphurization of the gas current.•From an economic point of view the proposed process is suitable.