A flexible design for computer programs to simulate mineral processing plants has been developed. A relaxation method is used to give rapid calculation of circulating loads and a Monte Carlo technique may be used to calculate accuracy estimates. Computer programs for the simulation of crushing and grinding plants have been written. An example, of the use of these, optimises a multi-stage grinding circuit. The design of a system of data structures for Fortran is presented to show how to increase the flexibility of future process simulation programs.
A model building technique has been developed to take advantage of both theoretical and empirical information about the unit being modelled. The procedure is presented as a series of steps and a proposal to automate these steps is presented. An improved regression technique using spline functions in one or more variables instead of analytic functions was developed to aid the model building. This multiple spline regression has been extended to include, periodic spline functions. An example, to show how an analytic base for the model building technique can be derived, develops a matrix theory of comminutioi machines.
Data from a large scale industrial crushing plant has been collected and used in the model building technique to obtain models of a cone crusher and a vibrating screen. These models were combined to produce a model of the complete crushing plant . Simulation of the plant was used to design and evaluate a control system which when installed on the plant provided a 15% to 20% increase in plant capacity, The optimum control settings for a delay line in this plant were also calculated. Further simulations have been used to calculate the operating curves for this plant under automatic control.