PREDICTION THE PRODUCT PARTICLE SIZE DISTRIBUTION OF VERTIMILL

A test campaign with a pilot scale VertiMill was performed with samples of iron ore and copper ore from Vale S.A. in order to evaluate the application of this type of equipment in primary grinding. Professionals involved in the design of new grinding circuit have discussed a lot about what methodology to use to scale-up VertiMill. This paper presented a new methodology for VertiMill scale-up and simulation by population balance model using parameters determined through results from a conventional tubular batch ball mill. The test requires small amounts of samples and can be carried out in any laboratory that has a batch ball mill. To determine the breakage parameters it was used BatchMillTM software, which interpolates different particle size distributions from batch tests to obtain parameters that represent a wide range of VertiMill operation. These breakage parameters were used to simulate the pilot scale tests using the ModsimTM software, which simulates the operation of grinding and classification equipment. The simulation results indicate that it is possible to predict the particle size distribution of the VertMill product with acceptable accuracy using the methodology proposed