we need discontinuous improvements in mineral liberation energy efficiency noko phala ceec short...

We Need Discontinuous Improvements in Mineral Liberation Energy Efficiency

Noko PhalaCEEC Short TalkJune 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

Refractoryores

Margin contractionOz 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 ComminutionMechanisms

$/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 ParticlesMisdirected impacts (misses), mismatched energies

Compression of Multiple ParticlesDirected energy application, mismatched energies

Step-wise Compression of a Particle andits Daughters IndividuallyDirected energy application, energy matching

Shocking of Multiple ParticlesDirected energy application, mismatched energies

Step-wise Shocking of a Particle andits Daughters IndividuallyDirected energy application, energy matching

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Step-wise Tension to a Particle and its Daughters IndividuallyAs 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