Publication: Determining the Bond Efficiency of Industrial Grinding Circuits Guideline (Revision)

December 16, 2021

Resistance does matter. Ask any metallurgist what can tip the balance between profit and loss, and they’ll tell you it often comes down to the rock – the cost of crushing that rock.  

Determining the Bond Efficiency of Industrial Grinding Circuits describes the Bond method for quantifying and comparing the relative energy efficiency of most industrial comminution circuits. It’s also an effective teaching tool that can be used by junior engineers looking to understand how apply this method. This minor revision of the guideline originally published in 2016 contains additional context and clarification. 

The Bond Work Index, published by Fred Bond in 1952, was a revolutionary theory that helped mining engineers measure rock hardness and its resistance to being crushed. The harder the rock, the more energy it takes to crush it, the higher the mine’s energy bills.  

Rob McIvor, Chief Metallurgist at Metcom Technologies explains, “By relating power consumption in crushing and grinding to the feed and product size distribution, the Bond Work Index and Bond Work Index Efficiency are widely accepted throughout industry as the standard benchmarking tool essential for the design, improvement and management of comminution circuits. Metcom Technologies has continuously promoted and trained others in Bond’s methods as a required element for process improvement of mineral comminution circuits.” 

Leonard Hill, Director of Metallurgy and Strategic Planning Technical Services, Freeport-McMoRan agrees, “As we move towards defining and reducing the cost of carbon in our industry, understanding and optimizing energy usage at mining operations has become a high priority. Determining the Bond Efficiency of Industrial Grinding Circuits is a practical GMG guideline that can be used by operators and designers to evaluate the energy usage efficiency of comminution circuits. It provides a step-by-step method for collecting samples, analyzing data and calculating the Bond Work Index efficiency ratio of a circuit for benchmarking and identifying process improvement opportunities.”  

The Global Mining Guidelines Group (GMG) brought together a project group of global subject matter experts to collaborate on producing this latest release. McIvor notes, “The numerous contributions of comminution experts from around the globe has led to this rigorously vetted guide for the determination of Bond efficiency in industrial grinding circuits.”  

“GMG’s goal when facilitating these collaborative opportunities is to end up with a product that helps drive the industry forward,” says Andrew Scott, GMG Vice-Chair Working Groups and National Cluster Development Manager, METS Ignited. “Our member mining companies and subject-matter experts from within the mining community asked us to provide a neutral, collaborative space where they could update the previous guideline and ultimately publish a timely and educational product.”  

Read the guideline here

GMG also published a revised edition of The Morrell Method to Determine the Efficiency of Industrial Grinding Circuits. It is also available on the GMG Guidelines Page.

About GMG 

The Global Mining Guidelines Group (GMG) is a network of like-minded companies driving change in the mining industry. Together, we help develop knowledge, educate, and guide the global mining industry. We monitor the pulse of the industry and develop multi-disciplinary guidelines and strategies to manage risk, enhance performance, design solutions, inform planning and decision making, and save time and money. Our members are mining companies, original equipment manufacturers (OEMs), original technology manufacturers (OTMs), research organizations and consultants from around the world who recognize that innovation does not happen in silos. GMG improves communication and facilitates collaboration to foster a more sustainable and efficient future for mining. Our multi-stakeholder working groups address topics such as interoperability, data access and usage, artificial intelligence, autonomous equipment, underground communication, battery-electric equipment, and comminution efficiency in mining. For more information contact us here



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