We Need Discontinuous Improvements in Mineral Liberation Energy Efficiency Noko Phala CEEC Short Talk June 2012

We face several sustainability challenges …. Environmental and social responsibilities – reputational risks Skills availability and retention Employee safety – conditions (e.g. seismicity) and practices Inflationary cost pressures – energy price, mining inputs, wages There is scope for technology and innovation to steer the tankers = + $/t Hard ores (energy cost) High consumables demand and costs inflation Low grades Refractory ores Margin contraction Oz Rec/t

..and this has in turn led to a broad technology development spectrum

The most common grinding method – tumbling mill – is inherently energy inefficient. Whilst continuous optimization is necessary, we believe the sustainability challenges require radical breakthroughs in energy utilization Tromans (2008) analysis: Considering energy of resultant surface The base energy requirement is a grinding method independent analysis; The challenge to obtaining it is overcoming the kinetic barriers;

Discontinuous improvements in energy utilization – encouraging directions Pre-upgrading Pre-treatment Electric pulses Ultrasound Microwaves …etc ? $/t cost savings directly related to % waste rejection Sensor-based sorting : exploration of other attributes ? Ore dilution can be ~ 200 % in a deep level mine Is a HPGR just an efficient crusher ? VRM for finish grinding ? VSI potential? Explore other mechanisms … New Comminution Mechanisms $/t energy saving related to degree of ore softening Complete elimination of a tumbling mill should be the goal Just how close to the thermodynamic limit can we get ? Are we aggressive enough in pushing ideas through the development systems?

Can we comminute based on a new set of rules ?

Destruction of a solid – define optimal breakage mechanism, then design a fitting device…we feel like we are stuck with optimising existing devices  Multiple Impacts on Multiple Particles Misdirected impacts (misses), mismatched energies Compression of Multiple Particles Directed energy application, mismatched energies Step-wise Compression of a Particle and its Daughters Individually Directed energy application, energy matching Shocking of Multiple Particles Directed energy application, mismatched energies Step-wise Shocking of a Particle and its Daughters Individually Directed energy application, energy matching Decreasing energy consumption ? Step-wise Tension to a Particle and its Daughters Individually As above or better ? What about shear and torsion ?

Going Forward The nature of the sustainability challenges we face make an innovative mindset a business imperative - wild ideas are becoming normal part of project trade-offs; From policy and industry “statements” to radical approaches and executable industry roadmaps: how do we become more aggressive in pursuit of the goals ? Being more open, and reaching out more to fields outside ours for solutions to our problems;

Open innovation – Creativity on demand, access the global brainpower