Project duration: 1 January 2019 – 30 June 2021


The GREENY project focuses on increasing the energy efficiency of comminution and enabling the beneficiation of difficult to process secondary raw materials.  The raw slag, containing less than cost beneficially required of extractable metals, is to be used as a separate product for construction materials after comminution. During the project, emphasis is placed on improving and upscaling suitable crushing and grinding technologies for slag material to enhance the energy efficiency and performance of crushing equipment in demanding operational conditions. The processes are developed in general with difficult to refine secondary raw materials in mind, for example, materials which contain both brittle and ductile phases.

The solution (technology)

These objectives are met by upscaling new crushing and grinding processes and applying them to presently unused sources of secondary raw materials. As a use case, the GREENY project takes on the efficient reuse of the steel industry’s slag that is a side product in steel making. The design and optimization methodologies, processes and equipment that are developed are applicable also to other slags and secondary raw materials. In the GREENY use case, the slag contains valuable metals that can be extracted by a combination of selective comminution and metal liberation from the slag.


  • Metso Minerals Oy, Finland (Lead Partner)
  • ERAMET IDeas, France
  • Luleå University of Technology (LTU), Sweden
  • Technische Universität Bergakademie Freiberg (TUBAF), Germany
  • Teknologian tutkimuskeskus VTT (Technical Research Centre of Finland Ltd. VTT), Finland