Analysis of single-particle breakage by impact grinding

doi:10.1016/S0301-7516(96)00008-7

International Journal of Mineral Processing

Volume 49, Issues 3–4, April 1997, Pages 223-236

https://doi.org/10.1016/S0301-7516(96)00008-7 Get rights and content

Abstract

A model is presented for breakage of single particles as a function of the impact energy. The model is based on a hazard function for test particles in impact energy in order to takes explicit cognizance of the distribution of feed particles in their resistance to breakage as well as the weakening of particles under repeated impacts. With this approach, it is possible to simulate the size spectra of progeny particles produced in impact grinding as a function of the impact energy employed, interrelate quantitatively the so-called t-family of curves, compute the primary, energy-free breakage distribution function, and predict the optimum level of impact energy for a given size reduction task. Extensive published data of Pauw and Mare on single-particle impact grinding are in agreement with the model.

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To reach faster adaptability, a deeper understanding of the fundamentals is necessary and thus, PBM is increasingly based on mechanistic models derived from DEM simulation or model experiments, allowing fast adaptions to new materials. The influence of past stresses below the particle strength, not leading to breakage, are considered in current research for modelling of the breakage rate Han et al., 2003; Vervoorn and Austin, 1990; Tavares and King, 2002; Morrison et al., 2007; Kapur et al., 1997; Vogel and Peukert, 2003; Tavares, 2009, but have not yet been taken into account for the breakage function. However, for impact breakage in the millimetre range, Tavares (2009) found that limestone broken with the same energy in the first impact event shows slightly smaller fragments than particles broken after several impact events.
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Research paperAnalysis of single-particle breakage by impact grinding

Abstract

Powder Technol.

Miner. Eng.

Int. J. Miner. Process.

Powder Technol.

Powder Technol.

Int. J. Miner. Process.

Prallzerkleinerung von Glas-Kugeln and unregelmassig geformten Teilchen aus Schwerspat, Kalkstein and Quarzsand

Chemie-Ing.-Techn.

Research paper
Analysis of single-particle breakage by impact grinding