Cone crushers are commonly used for secondary and tertiary crushing stages in the aggregate and mining industry。 It has previously been demonstrated that the discrete element method (DEM) can be used to simulate rock breakage in crushers using a variety of modelling techniques。 In order to provide confi-dence in the simulation results the DEM models need to be validated against experimental data。 Such val-idation efforts are scarcely reported in the existing literature and there are no standardized procedures defined。 In this paper a laboratory cone crusher is simulated using DEM and the results are compared with laboratory experiments。 The rock material is modelled using the Bonded Particle Model approach calibrated against single particle breakage experiments。 Two case simulations have been performed investigating the influence of eccentric speed。 The laboratory crusher is a Morgårdshammar B90 cone crusher that has been equipped with custom machined liners, variable speed drive and a National Instruments data acquisition system。 The results provide novel insight regarding the stochastic flow behaviour of particles when exited by the mantle at high frequency。 The estimated product size distribu-tion matches the experimental results relatively well when evaluating the corresponding coarse region that is feasible to calculate from the DEM product discharge data。79858

1。 Introduction

The cone crusher is the most common machine type for sec-ondary and tertiary crushing of hard rock materials in the minerals processing industry。 During recent years, minerals processing experts and engineers have shown an increased interest in the operation of primary and secondary crushing and potential efforts to optimize the performance and operation have followed。 This interest directs focus on modelling and simulation capabilities in order to provide accurate and robust predictions。 Models com-monly range from relatively simple empirical analytical models to mechanistic analytical models and numerical models which for instance, utilize the discrete element method (DEM)。 The required quality and applicability of the different modelling approaches depends on why it is applied。 If the model is used in a fast and simple steady state simulation; a fitted empirical size reduction model may be enough, at least if the prediction capabil-ity limitations are well understood and considered。 In cases where, for instance, the influence on circuit performance due to a crusher liner design change is evaluated, a more advanced mechanistic crusher some kind of methodology needs to be applied in order to facilitate a useful description of the actual breakage events and how rock particles break apart。 The three most common approaches used for modelling breakage in DEM are listed below:

Bonded Particle Model (BPM) - Spheres are arranged in a cluster and bonded together in each contact point using bonding beams ( Potyondy and Cundall, 2004)。 

Particle Replacement Model (PRM) - Particles are replaced by a set of progeny fragments at the breakage event ( Cleary, 2001)。 

Tetrahedral Element Model (TEM) - Particles are modelled using a tessellated mesh structure using voronoi grains, polyhedrons or trigons ( Cundall, 1988; Potapov and Campbell, 1996)。 

All of these three approaches have been used for modelling compressive breakage in cone crushers。  Herbst and Potapov  (2004) used a version of the TEM method but only displayed results from a 2D simulation of a crusher。 The TEM approach was later applied in 3D by the same group for modelling a Morgård-shammar B90 laboratory crusher ( Lichter et al。, 2009)。 The PRM method has successfully been implemented for cone crusher sim-ulations by Cleary, Sinnott and Delaney ( Cleary and Sinnott,  2015; Delaney et al。, 2015)。

The BPM method has previously been applied for modelling of breakage in cone crushers by the authors in a series of publications ( Johansson et al。, 2015; Quist and Evertsson,  2016, 2010; Quist et al。, 2011)。 The BPM model is implemented on clusters of sub-particles assembled with the shape from 3D scanned rock particles。 The micro properties of the BPM model were calibrated against single particle breakage experiments and the results have been compared to industrial scale experiments。 The experiments were conducted on a Svedala H6000 cone crusher and the power draw and pressure signals were measured using a custom data acquisition system with a sampling rate of 500 Hz。