Study on Preparation and Carbon Sequestration Performance of Carbide Slag-CFB Fly Ash Composite Particles

Using industrial solid waste carbide slag as calcium source, novel composite particles were prepared by adding circulating fluidized bed (CFB) fly ash and cement for modification and coupling with curing process. Results show that the high content of CaO in carbide slag provides a strong alkali environment for the system, and a large number of hydration products such as C-S-H gel and ettringite are generated in the hydration process of the optimal ratio group. The strength of the sample after 28 days of curing reaches 4.619 MPa, which is about 109% higher than that of 1 day curing. The initial CO₂ adsorption capacity of the composite particles reaches 0.34 g/g, and at 850 ℃, the CO₂ adsorption capacity only decreases by 31.5% after 16 cycles. The adsorption isotherm conforms to double exponential model, and the kinetic data conforms to quasi-second-order model, indicating that the adsorption process is controlled by chemical bonding.