As an emerging carbon capture and storage ( CCUS) technology，wet carbonation and storage of CO₂ from ferrous metallurgical slag has shown significant economic value due to its dual benefits of raw material resource utilization and carbon storage. This paper discusses the influence of time，temperature and CO₂ airflow flow on the carbonation efficiency of Ca ^{2 +} extract，and analyzes its restrictive links in combination with the reaction kinetic model; the morphological characteristics of the product are characterized by SEM and X-ray diffraction ( XRD) . The experimental data show that with the increase of temperature and time，the degree of carbonation first increases and then decreases. With the increase of gas flow，the degree of carbonation decreases first and then increases. The optimal reaction conditions are 22. 5 min at a CO₂ gas flow rate of 0. 1 L/min and a temperature of 60 ℃，and the carbonation rate is 68. 03%. Combined with the Arrhenius equation，the apparent activation energy is calculated as 24. 45 kJ/mol，which indicates that the reaction system is controlled by both surface chemical reaction and gas-liquid boundary layer diffusion. The product characterization shows that the purity of the synthetic calcium carbonate is 99. 37% ，and its crystal structure is mainly stable calcite and aragonite，and the proportion of calcium carbonate products ＜ 0. 075 mm fraction is 93. 6% ，which meets the quality standards of industrial precipitated calcium carbonate ( PCC) and could be widely used in papermaking，plastics and building materials. This study can provide key process parameters and theoretical support for synergistic carbon storage technology of metallurgical solid waste.