Project Details
Projekt
Numerical investigation of the liberation of critical raw materials in the form of Engineered Artificial Minerals (EnAMs) from tailored solidified slag phases by DEM-based comminution
Applicant
Professor Dr.-Ing. Harald Kruggel-Emden
Subject Area
Mechanical Process Engineering
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 470536680
There is a constant need for minerals, metals, and natural materials in the development of new technical applications. These materials include so-called critical raw materials, which are categorized due to their importance to a variety of industries and their supply risk. It is essential for Europe’s transition to climate neutrality to ensure diversified and undistorted access to global markets for these raw materials. This can be achieved by reducing, reusing and recycling the critical raw materials already in circulation and by finding new sources Slags from pyrometallurgical processes present a potential new source of critical raw materials. Traditionally, pyrometallurgical processes aim to improve the quality, yield, economic feasibility of the main phase, and all other elements are driven into the secondary liquid slag phase. During solidification the slag either forms a homogeneous amorphous structure or produces crystals. These crystals are considered as artificial minerals, referred to as Engineered Artificial Minerals (EnAMs), and are a source of valuable elements. EnAM recovery requires the liberation of EnAM crystals by comminuting the slag into particles, followed by further separation. Overall aim of the proposed research work is to contribute to the prediction of EnAM liberation from tailored slag systems by utilizing multiscale Discrete Element Method (DEM) modelling and to derive and extend liberation process models based on it. Breakage in this model depends on both EnAM constituents and grain texture of a particle. This extends the dependencies considered in the first funding period (FP1) of PP 2315, where breakage was realized only dependent on EnAM constituents. To include mineral liberation run-time efficient in the DEM, the bonded particle model (BPM) in combination with experimental single particle investigations is utilized to derive the breakage criterion and breakage function of a particle as part of a particle replacement method (PRM) approach. A liberation process model is derived and extended for the first time in the context of EnAM liberation, based on DEM modelling by BPM and PRM, and accompanied by experimental investigation on the single particle (piston-die) and the apparatus level (roller crusher/mill). This model can be used for quick process evaluation and optimization in the context of EnAM liberation. Both the DEM models and the liberation process model will be calibrated to the slags considered throughout the second funding period (FP2) of PP 2315. This will allow for an understanding of the mode of breakage for EnAM liberation and the selection of optimal process conditions in this context. The successful completion of the second funding period of PP 2315 enables the novel DEM framework and the liberation process model to be deployable at best for predictive liberation modelling, involving both EnAMs and natural minerals in the future, which is currently still in its infancy.
DFG Programme
Priority Programmes
