Trio of guidelines offer best practices methods for circuit analysis

GMSG’s Industrial Comminution Efficiency Working Group (ICE) has successfully published its three comminution efficiency guidelines involving the Bond Work Index, the Morrell Method, and Surveying and Sampling. Each guideline is part of a greater effort to reduce energy usage in the ore grinding process.

Comminution Efficiency accounts for the highest energy usage in the mining industry. According to a report by the Coalition for Energy Efficient Comminution, grinding and crushing ore accounts for 53 per cent of an average mine site’s energy consumption. All three guidelines have been developed as best practices for circuit analysis techniques and methods.

Use of the Bond method and the comprehensive Bond Work Index allows personnel to quantify and compare relative energy efficiencies, offering a mode of benchmarking to observe energy consumption. With these benchmarks in place, operators can measure output and adjust as necessary to create cost-efficient and energy-efficient solutions. The Morrell method utilizes data from the SMC Test to predict an ore body’s comminution circuit in order to determine energy consumption depending on the ore’s properties.

Using the comminution measurement approaches of the Bond Work Index and the Morrell method, the surveying and sampling guideline details methods to survey and sample grinding circuits to generate sufficient information of suitable quality to support reliable efficiency analysis by these and comparable methods. It deals specifically with surveying and sampling Autogenous Grinding (AG), Semi-Autogenous Grinding (SAG), rod, and ball mill circuits operating within the normal range of application.

“The Bond and Morrell methods, when applied in parallel to an analysis, give the user a means to cross check conclusions,” says Aidan Giblett, Senior Technical Advisor, Mineral Processing at Newmont Mining Corporation, and ICE Working Group leader. “This is particularly important when comparing one operating condition to another, as the methods should indicate a comparable change in efficiency. This can provide important validation of any conclusions drawn from circuit analysis.”

GMSG would like to extend a sincere thank you to all who made the publication of these three guidelines possible, with a special thank you to Giblett, Robert E. McIver, Alex Doll, James Connelly and Michael Daniel. Potential next steps for the working group will be to create an online database and benchmarking tools to monitor the effectiveness of the guidelines in practice.

All three guidelines, “Morrell method for determining comminution circuit specific energy and assessing energy utilization efficiency of existing circuits”, “Determining the Bond Efficiency of industrial grinding circuits” and “Methods to survey and sample grinding circuits for determining energy efficiency” are available to download from the GMSG library. For more information on GMSG’s guideline work, please contact Heather Ednie.

Download the full press release here.