Influence of gypsum’s mineralogical characteristics on its grinding behaviour applied to cement fabrication

In an industrial process of cement fabrication, the use of mixtures of 95% clinker and 5% gypsum with two different kinds of gypsum (similar chemical composition but different source) results in grinding power consumption differences up to 15%. The mentioned differences are not explained when performing power consumption evaluations according to Bond’s method. On the other hand, studies of both gypsums by means of transparency microscopy show their differences in textural characteristics and lead to the explanation of such a behaviour difference, as much in grinding in the industrial process as in the laboratory tests. The transparency microscopy continues being a recommended tool in the selection of appropriate raw materials in the cement industry.