Using discrete simulation for a mine mill

A simulation model of the materials flow through a mine mill can have important practical applications. Unlike a materials balance model that tends to balance the output to the input of the mill, a discrete system simulation model follows the progression of a single unit of material through the various stages of the mill. A unit of ore passing through the system can be considered as a discrete element It should be possible to model the mill using discrete system simulation techniques. This was done for a generic, working mill using the GPSS/H(tm) language and PROOF Professional(tm) animation. The model assumed that the mill feed was assumed to be in so many units/minute. This rate was taken to be a variable which could change during the simulation. The milling rates could also be sped up or slowed down. This example shows that it is possible to use a language such as GPSS/H to model continuous flow in a mill. The basic flow of material was from a single crusher through a set of crushing devices (either ball, rod or autogenous could be used here), into the floatation cells, to the driers and into various stockpiles. The whole program was written in modular form so that it can be eventually incorporated into a larger program which includes the mining of the ore. The animation model used shows the working of the mill in "cartoon" fashion.