The GMSG is an international organisation one of the aims of which is to promote best practices in the mining industry. Its corporate members, partners and collaborators include the largest and most influential organisations in the mining world.
The guideline describes the “Morrell” approach for predicting the specific energy requirements of conventional crushing, High Pressure Grinding Rolls and tumbling mill circuits through the use of the SMC Test® as well as how to assess the energy utilisation efficiency of existing comminution circuits. As Barrick, the largest gold producing company in the world reported, this methodology was one of the key technologies employed by them in a program started in 2008. This program lead to significant savings at a number of Barrick’s operations which have been quoted as follows*:
“Results have been very positive with more than 20% net grinding energy improvement in one case. These actions have lead to more than 43,000 tonnes per year reduction in CO2 emissions in the three operations reviewed. Relative to Barrick’s total “carbon footprint”, this represents a net efficiency improvement of almost 1% and supports one of the key pillars of Barrick’s climate change standard. Overall the three sites reviewed have reduced energy consumption by about 61 million kWh per year in relative terms. This cost saving of about $5 million per year has been further augmented with more than 200 combined tonnes per hour of throughput providing in the order of 60,000 ounces of gold annually.”
The SMC Test® was developed by Morrell in 2003 and has since become one of the most popular and successful laboratory tests in the world for characterising the breakage properties of ores. To date the number of SMC Tests conducted has reached a staggering 40,000 which cover over 1400 deposits from 82 different countries. The SMC Test® is used extensively in the design of greenfield/brownfield comminution circuits and in geometallurgical modelling.
Copies of the guideline can be obtained on-line from the GMSG library using the following link:
http://gmggroup.org/guidelines/
*Buckingham, L., Dupont, J., Stieger, J., Blain, B., and Brits,C. 2009,”Improving Energy Efficiency in Barrick Grinding Circuits” , Proceedings of SAG 2011, Vancouver, Canada, paper #150