Thermodynamic modeling of the synthesis of the main minerals of cement clinker from technogenic raw materials

In this article, thermodynamic studies of modeling the formation of the main minerals of cement clinker as a function of the Gibbs energy (Delta G) on temperature were investigated. The temperature range of the studies was 873-1873 K. In the course of modeling studies, the reactions of formation of cement clinker minerals (C2S belite, C3S alite, C(3)A - three calcium aluminates, C(4)AF - four calcium aluminium ferrite) from standard raw materials and non - standard-technogenic raw materials containing non-ferrous metals were calculated. Equations describing the dependence of the Gibbs energy on temperature with approximation coefficients (R-2) equal to 0.99 are found. According to the results of the conducted studies, the beginning (Tb) temperatures of the course of the compared clinker formation reactions were determined, which were 1008 K for the standard reaction, and 1023 K for the non-standard reaction. It was found that the reactions begin to occur in the temperature intervals for the standard (1008 K - 1873 K), for the non standard (1023 K 1873 K). At the same time, the values at the initial stage of the course of the standard reaction have a more negative value of the Gibbs energy than the non-standard reaction. With a further increase in temperature, it becomes evident that the Gibbs energy of the non-standard reaction of mineral formation in the temperature range 1173-1873K becomes more negative in comparison with the values of the standard reaction and exceeds its values from 9 to 19.01%.