C emQUANT ® software Mathematical modeling in quantitative phase analysis of Portland cement

Abstract

It is necessary to determine a complete mineralogy of clinker cement to correctly understand, interpret, and predict the outcome of any plant production process. The cement industry's standard method (ASTM C 150) used in quantitative phase analysis of alite, belite, aluminate, and ferrite has long been known to provide approximate concentrations. The wet chemical and optical microscopy methods are too slow and too expensive to be used on a large scale. The X-ray diffraction-based Rietveld method features its own limitations and so far has been used in a very small number of industrial laboratories. This article describes original commercial software named C emQUANT, employed for major and minor phase quantification in Portland cement. C emQUANT's input data consists of up to 17 constituents, such as CaO, SiO 2, Al 2O 3, Fe 2O 3, TiO 2, Mn 2O 3, SrO, MgO, Na 2O, K 2O, P 2O 5, SO 3, and loss of mass (LOM). Minor element oxides and LOM are essential if a full mineralogy is to be calculated and a high accuracy output data is to be obtained. Using a novel mathematical modeling approach, the input constituents are distributed among preselected mineral phases in such a way that the input and output mass balances are matched. The phases automatically quantified by C emQUANT are: alite, belite, aluminate, ferrite, aphthialite, gypsum, bassanite, lime, calcite, periclase, KC 8A 3, NC 8A 3, langbeinite, thenardite, KC 23S 12, arcanite, C 4AMn, and anhydrite. In comparison with Bogue calculation, C emQUANT is much more accurate for major phases and provides concentrations of additional secondary phases. Fifteen international clinker cement reference materials were analyzed using C emQUANT and obtained phase concentrations were compared with data from Bogue calculations. Main methods used in clinker cement phase quantification are discussed and compared with C emQUANT.