AG/SAG mill acoustic emissions characterisation under different operating conditions

Towards the development of an improved and more efficient online monitoring system in an industrial AG/SAG grinding mill, the present study employs a laboratory-based AG/SAG mill and acoustic sensor to investigate the acoustic characteristics of different mill operating conditions. Specifically, mill operating conditions such as empty mill, individual charge compositions and their combinations, together with different lifter heights and mill speeds were studied. The results showed remarkable acoustic emission in ball only load and reduced in order of ball-water, ball-rock, rock-ball-water, rock only, rock-water, water only and no load. Water and rock showed minor and major dampening effects on the mill acoustic emission, respectively, in the presence of steel balls. Generally, mill rotational speed, charge load as well as lifter height variations reflected well in the mill noise emission. This study supports the use of mill acoustic sensing technique to understand different grinding conditions in AG/SAG mills for improved and continuous process monitoring, energy-efficient milling, and enhanced optimisation.

Automated summary

This study investigated the acoustic characteristics of different mill operating conditions using a laboratory-based AG/SAG mill and acoustic sensor. The results showed variations in acoustic emission under different load conditions and the dampening effects of water and rock on mill noise emission in the presence of steel balls. Mill rotational speed, charge load, and lifter height variations were found to be reflected well in the mill noise emission, supporting the use of mill acoustic sensing technique for improved process monitoring and optimization in AG/SAG mills.