COMPUTER-AIDED GRINDING CIRCUIT OPTIMIZATION UTILIZING A NEW MILL EFFICIENCY CURVE

Grinding circuit optimisation is a complex problem requiring suitable decision aids. Both the need to reduce experimental costs and the impr oving reliability of mathematical modelling are leading to a growing a cceptance of computer simulation methods by engineers in mill design a nd grinding practice. Using a minimum parameter grinding model for tum bling mills, the authors have developed the ''reference state method'' for the calculation of grinding systems. The method enables predictio n of system behaviour when changes occur in the most important variabl es and parameters. A new ''mill efficiency curve'' analogous to the no rmalised grade-efficiency curve for describing classifier behaviour, i s suggested. It describes a unique size-dependent mass flow through th e mill to obtain a certain fineness condition. The curve is relatively invariant over a reasonable range of conditions. It is excellently su ited for objective evaluation and simulation. The wide application ran ge of the method is illustrated by typical examples, showing the advan tages both of the method and of the corresponding complex software sol ution ''CGC - Calculation of Grinding Circuits''.