An integrated reclaimed process of refining slag with calcium-containing wastewater for CO2 mineralization and utilization by using a high-gravity carbonation process was proposed in this study. The effect of various liquid agents on calcium ion leaching behavior from the refining slag was determined and the mass-loss method was used to evaluate the leaching kinetics. The influence of different high gravity factor and liquid-to-solid ratio on carbonation conversions were investigated and the reaction kinetics were identified via surface coverage model. The efficacy of refining slag utilized as supplementary cementitious materials including workability and mechanical strength was assessed. The morphological, mineralogical, and thermal analyses were carried out and the results revealed the presence of calcite to support the carbonation theory. The results of maximal CO2 capture capacity of 0.183 g CO2 per g slag and performance of carbonated slag utilization with 5% and 10% substitution ratio confirmed the feasibility of the integrated reclaimed process.