Abstract:
In order to reduce the carbon footprint of cement industry and recycle carbide slag, carbide slag was added into carbonation curing cement as the mineral admixture. The influence of carbonation curing on the compressive strength, drying shrinkage, chloride ion penetration of cement paste added with carbide slag was studied, and the microstructure of cement paste was analyzed by X-ray diffraction, thermal analysis, mercury intrusion porosimetry, scanning electron microscopy, etc. The results show that carbonation curing can improve the compressive strength and chloride ion erosion resistance of cement paste added with carbide slag, reduce the electric flux by 38.17%-50.08%, reduce the 56 days drying shrinkage by 8.8%-25.2%, and refine the pore structure. About 10% of carbide slag can be used as resource under the premise that the strength of cement paste is not reduced, and the carbon fixation rate of cement paste can reach 11.19%-15.87%. The purpose of capturing and solidifying carbon dioxide, recycling carbide slag and improving the performance of cement paste are achieved by carbonation curing.