The Kinetic Study of Carbonation of BOF Slag at High Temperature: Impact of Particle Size Characteristics

Basic oxygen furnace slagBasic oxygen furnace slag (BOF slag) (BOFS) with high content of free CaO (f-CaO) can be utilized as a kind of building materialsBuilding material after carbonation. However, the degree of carbonation varies greatly depending on the particle size of slagSlag. In this study, the carbonation processProcess of BOFS with different particle sizes was evaluated in an autoclave. The highest CO2 sequestrationCO2 sequestration and f-CaO consumption reached 6.49% (64.9 g CO2/kg slagSlag) and 99.81%, respectively, when the particle size of BOF slagBasic oxygen furnace slag (BOF slag) was less than 61 μm. Additionally, the size of particles had a minor impact on f-CaO consumption but significantly affected CO2 sequestrationCO2 sequestration. With CO2 sequestrationCO2 sequestration as an indicator, the results showed that the carbonation of BOFS was accurately described by the shrinking core model and the carbonation processProcess was proved to be controlled by internal diffusion. The effectiveness and environmental benefits of this method make it worth promoting for the carbonation and stabilization of steel slagSteel slag.