| Abstract Scope |
Bauxite is a rock composed of minerals and impurities. The main components in bauxite are kaolinite, gibbsite, hematite and anatase. Gibbsite is one of the minerals important for aluminum production. In the mining industry, quantification of minerals and impurities is needed, with gibbsite being reported as available alumina, and kaolinite, one of the major impurities, as reactive silica. The precision of these analysis results influences figuring out the KPIs needed to define the productivity of the Bayer process, aiding the decision making process. So, it is necessary to apply a robust methodology to ensure the quality of a quantitative analysis, such as repeatability and reproducibility analysis (R&R). The R&R analysis of these measurements was performed at Hydro Alunorte (Barcarena/PA/Brazil) with 3 different bauxite samples and applying an ANOVA statistical analysis. P- and T values of 6.5% and 10% were achieved for the analysis of available alumina and reactive silica, respectively. With the data it was possible to find opportunities for improvement, reduce deviations, and guarantee quality and reliability in the Bayer process. |