Multivariate Specifications of Raw Materials: Application to Aluminum Reduction Cells

A metallurgical process generally processes some raw materials or ores into concentrates or primary metals using different technologies. However, the quality of the incoming raw materials has an effect on the process performance. Hence, engineers have to apply different set points in order to account or compensate for raw material quality variations. This is frequently performed using a set of univariate specifications. In this paper, a methodology to build multivariate specifications is presented and illustrated using a case study from an aluminum reduction smelter.