Challenge
Our team were engaged to conduct a technical investigation into a negative copper recovery step change at a mid sized copper/gold producer
The outcomes indicated that the grind size had shifted with respect to the throughput rate with the same ore types
- Recent circuit modifications introduced a bypass which directed a significant amount of water away from the milling circuit directly to flotation creating low milling circuit classification efficiencies
Solution
Designed, coded and commissioned constraint controllers to optimally balance the water throughout the circuit to improve overall grinding circuit efficiency and ultimately grind size
Developed models to optimally find the constraints at points with multiple variables. Examples include cyclone roping conditions and underflow tub level prediction
Results
Improved grind size to flotation at the same throughput rate and ore types by a statistically significant 5um, or 0.7% Cu and Au recovery
Trained and coached operations and technical teams in the use of the water balance controllers
Due to high leel of operator engagement during the process, control loop utilisation has remained high resulting in reduced shift to shift variation
