Methods to Survey and Sample Grinding Circuits for Determining Energy Efficiency

This guideline covers surveying and sampling Autogenous Grinding (AG), Semi-Autogenous Grinding (SAG), rod, and ball mill circuits within the normal range of application. The intended application of this analysis is to treat a complete grinding circuit as a singular process block, irrespective of the number of grinding stages or internal classification steps. This approach allows a quick, relatively low-cost assessment of overall grinding circuit efficiency and can identify if more detailed analysis or circuit optimization work is required. Following circuit changes, the same methods can be used to compare the impact on circuit efficiency of varying operating conditions. This approach removes the need to survey internal circuit streams and mass balance around classification stages, greatly reducing labour requirements, survey turnaround time, and costs associated with sampling, sample analysis, and circuit modelling. While the intent of this guideline is not to define a full grinding circuit survey procedure, the techniques described observe industry best practice and can provide a firm starting point to analyze mineral comminution circuits at any required level of detail.