SAG mill closed loop control

IGO Limited greatly improved grinding mill efficiency and stability using predictive control based on our 3DPM® online particle size distribution (PSD) measurement. Commissioning of 3DPM was done smoothly by remote connection, useful when not allowed to visit the mine.

IGO Limited, the owner and operator of the Nova Nickel Operation in Western Australia decided to purchase 3DPM after a successful trial. The purpose of the use of 3DPM was to increase knowledge and understanding of the material flow and hence improve the production efficiency and the product quality in the mine.

3DPM vision system provides on-line particle size distribution (PSD) measurements of rock and bulk material through 3D measurements on conveyor belts. In this case the size distribution is used as a “disturbance variable” in a model predictive controller for a SAG mill. The model can predict by up to 100 seconds in advance the effect on the SAG mill weight. This has greatly improved the stability of the grinding circuit as well as increased the energy efficiency of the Mill.

3DPM at IGO Nova Nickel operation

The rock bolt detection feature detects rock bolts in real time, alerting the operator and allowing them to stop the feed to remove the rock bolt. This feature enables IGO to act quickly and avoid unplanned downtime and costly damages.
IGO control systems engineers are currently looking at other ways in which the measurement can be used. One possible use is to use the measurement to track the wear of the jaw crusher liners. As the jaw crusher liners wear down, the average size of the crushed particles increases. This will allow IGO to do jaw crusher maintenance in a smarter way.