We Need Discontinuous Improvements in Mineral Liberation Energy Efficiency

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

2. 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 Refractory ores Low grades $/t + = Margin contraction High consumables demand and costs inflation Oz Rec/t Hard ores (energy cost)

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

4. 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 utilizationTromans (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;

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

6. Can we comminute based on a new set of rules ?

7. 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 Shocking of Multiple Particles Directed energy application, mismatched energies Compression of Multiple Particles Directed energy application, mismatched energies Decreasing energy consumption ? Step-wise Compression of a Particle and its Daughters Individually Directed energy application, energy matching Step-wise Shocking of a Particle and its Daughters Individually Directed energy application, energy matching Step-wise Tension to a Particle and its Daughters Individually As above or better ? What about shear and torsion ?

8. Going Forward The nature of the sustainability challenges we face make aninnovative 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;

9. Open innovation – Creativity on demand, access the global brainpower