Effect of CuO on the Burnability and Mineral Formation of High C3S Cement Clinker

The effect of CuO on the clinkering process and mineral structure, components and morphology of high C3S cement clinker was studied. One reference mixture was prepared according to the potential mineral phase components C3S=75%,, C(3)A=7%, C(4)AF=18% and then was mixed, respectively, with 0.5%, 1%, 1.5%, 2%, 2.5% and 4% CuO. All samples were heated at a rate of 10 degrees C/min to the design temperatures and then maintained for 40 min. Analyses by the glycerol-ethanol method, XRD and SEM-EDS show that the minimum of free lime (f-CaO) content was related to temperature and CuO amount. The higher the temperature, the lower the amount of CuO corresponding to the f-CaO minimum content. CuO promotes the formation and growth of C3S and C(4)AF and a new compound is found. In addition, these phenomena are discussed theoretically. In conclusion, CuO alters the burnability and the formation and structure Of C3S in a high C3S cement system.