Comparing power draw predictions in experimental scale tumbling mills using PEPT and DEM


A. Mainza, I. Govender, L. Bbosa, M. Powell, N. Plint




XXVI International Mineral Processing Congress - IMPC 2012



Positron Emission Particle Tracking (PEPT) and the Discrete Element Method (OEM) are used toinvestigate Power Draw in a laboratory scale tumbling mill. The mill is run dry in batch mode atdifferent speeds using mono-size charge of glass beads, and is mounted along with a torquetransducer to measure power. Particle tracking information from PEPT is used to reconstruct themotion of glass beads and infer the overall charge behavior, while OEM is employed to simulateparticle motion and interaction, with collision mechanics calculated using the Hertz-Mindlin contactmodel.For PEPT and OEM data, the product of torque and average angular velocities in discrete cells areaccumulated to obtain mill power. This method is found to be within statistical agreement wtthmeasured power for all tests. Spatial distributions plotted from this approach highlight the regions ofthe mill that draw the greatest power. A second technique to obtain Power Draw from OEM data whichsums particle forces against the mill geometry is similarly found to accurately predict mill power withlower statistical error.Conference website


dem, PEPT, Power Draw