By utilising raw materials, additives/correction materials, as well as secondary raw materials, primarily metallic impurities (iron, non-ferrous metals, stainless steel, etc.) are brought into the continuous raw meal grinding process and disturb the production of raw meal, causing damage and greater wear to the vertical mill and the conveyor aggregates. Currently, the partition of magnetic constituents of the feed is achieved by the utilisation of a magnetic separator. Since only partial separation of metallic impurities can be realised, subsequently, two serially-connected metal detectors are used. These metal detectors operate a discharge flap in case of metal detection to avoid that impurities are transported into the mill. The fraction at which the impurities are separated, can be conveyed to the mill again. The material flow containing impurities is internally referred to as “reject” and must be disposed of. This process is only minimally selective and therefore, the losses of valuable material are significant. In course of this thesis, representative sampling was conducted, and the relevant material flows were characterised regarding valuable material and impurities. Based on this, possibilities for efficient reduction of the impurities were identified and several variations for processing were compared. Viable aggregates for this application were proved regarding operational functionality and for integration in the existing process. Finally, a plant concept was compiled which is technically and economically realisable and under consideration of the local circumstances and logistics of material flows. The overall objective of this thesis was the compilation of a plant concept, whereby the process for separating impurities efficiently to avoid their insertion to the vertical mill and the reduction of losses of valuable material in the reject should be achieved.