Carbon Dioxide Capture and Product Characteristics Using Steel Slag in a Mineral Carbonation Plant

Carbon capture and storage (CCS) technology can reduce CO2 emissions by 85 to 95% for power plants and kilns with high CO2 emissions. Among CCS technologies, carbon dioxide capture using steel slag is a method of carbonating minerals by combining oxidized metals in the slag, such as CaO, MgO, and SiO2 , with CO2 . This study assessed the amount of CO2 captured and the sequestration efficiency in operating a mineral carbonation plant with a CO2 capture capacity
of 5 tons/day by treating the exhaust gas from a municipal waste incinerator and identified the
characteristics of the mineral carbonation products. As a result, the average concentration of CO2
in the inflow and outflow gas during the reaction time was 10.0% and 1.1%, respectively, and the average CO2 sequestration efficiency was 89.7%. This resulted in a conversion rate of CaO of > 90%. This study manifested that mineral carbonation products are more stable than steel slag as a construction material and are effective at sequestering CO2 by forming chemically stable CaCO3.