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
Dec
reas
ing
ener
gy c
onsu
mpt
ion
?
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