MPC Feed-Forward for Constraint Handling

In a mineral concentrator, ore is milled and later separated into concentrate and tailing by a process called flotation. When a milling line abruptly stops, a significant inflow disturbance to the downstream flotation series is often observed. To avoid de-tuning the flotation level controller to handle the worst case scenario, we introduce a feed-forward model predictive controller (MPC) that considers the closed loop system in its design. This addition to the control structure givesconstraint handling properties to the existing well-functioninglevel controller.