Processing of Waste from Enrichment with the Production of Cement Clinker and the Extraction of Zinc

Materials (Basel). 2022 Jan 3;15(1):324. doi: 10.3390/ma15010324.

Abstract

This paper presents studies on the processing of enrichment tailings as a component of a raw mixture in order to obtain cement clinker, with simultaneous distillation of zinc. Thermodynamic studies were carried out in the temperature range of 600-1600 °C using the software application "HSC Chemistry 6" developed by the metallurgical company Outokumpu (Finland). As a result of the conducted studies, we found that zinc contributes to the intensification of mineral formation of cement clinker. In particular, it was found that the formation of belite is possible in the temperature range from 990.7 to 1500 °C with Gibbs energy values of -0.01 and -323.8 kJ (which is better than the standard process by -11.4 kJ), respectively; the formation of alite is possible in the temperature range from 982.9 to 1500 °C with Gibbs energy values of -0.05 and -402.1 kJ (better than the standard process by -11.4 kJ), respectively; the formation of tricalcium aluminate is thermodynamically possible in the temperature range from 600 °C at ΔGTo = -893.8 kJ to 1500 °C at ΔGTo = -1899.3 kJ (better than the standard process by -1570.1 kJ), respectively; and the formation of four calcium aluminoferrite is possible in the temperature range from 600 °C at ΔGTo = -898.9 kJ to 1500 °C at ΔGTo = -1959.3 kJ (better than the standard process by -1570.2 kJ), respectively, with simultaneous distillation of zinc into a gaseous state for its further capture.

Keywords: cement clinker; enrichment tailings; technogenic material; thermodynamics; zinc metasilicate; zinc sublimates.

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