Build-up formation in cement kiln preheater: qualitative and quantitative mineral characterization

Abstract

Extracting more information about reactions and parameters governing the build-up formation process, in the preheater system of the clinker burning line, could be an efficient tool to better attenuate their formation. In order to control their appearance, diagnosis steps of mineralogical analysis application for process optimization (MAA-PO) are suggested. Mineralogical characterization is carried out on three samples taken from different layers of the same build-up. The qualitative and quantitative X-ray diffraction, combined with chemical analysis and IR study, shows that Ternesite is the key mineralogical phase responsible for their growth and consolidation. Its appearance is governed by solid-solid reactions promoted by the available sulfate liquid phases, mainly Ca –langbeinite, as well as C12A7 and C4AF presence. The hot powder calcination degree, SO3 amount, LSF, SR and MA are operational data that have been correlated to the build-up mineralogical analysis. Based on this correlation, it is possible to predict the reactions kinetics involving in each layer formation and to estimate the development time of each. Results showed that MAA-OP is a promised novel approach to optimize clinker production process parameters.