Plant-wide control of grinding mill circuits: Top-down analysis

A generic top-down control structure is proposed for the optimal steady-state operation of a grinding mill circuit. The economic cost function of the grinding mill circuit is defined with reference to the final product of the larger mineral processing plant. A mineral processing plant in this study consists of a comminution and a separation circuit. The comminution circuit's operational performance primarily depends on the mill's performance. Since grindcurves define the operational performance range of a mill, the grindcurves are used to define the setpoints for the economic controlled variables for optimal steady-state operation. For a given metal price, processing cost, and transportation cost, the proposed structure can be used to define the optimal operating region of a grinding mill circuit for the best economic return of the mineral processing plant.