Tuesday, 8 October 2013

GeoMet 2013

It was good to report on Dr. Megan Becker's recent award at World Gold '13. Megan, of the University of Cape Town, is MEI's consultant to Processing Mineralogy '14. Immediately following World Gold, GeoMet '13 was held at the same venue and Megan has kindly provided the following report: 


Monday 30th September

This morning Dr Simony Dominy from Snowden welcomed around 200 delegates to the 2nd AusIMM GeoMet conference which is held here in the Hilton Hotel, in Brisbane Australia. I have great expectations about the quality of this conference, which follows on from the highly successful inaugural GeoMet conference, also held in Brisbane in 2011. The conference was formally opened by Alice Clark, the immediate past president of the AusIMM. Alice duly noted her thanks to all the sponsors: especially for the platinum sponsor FLSmidth (FLSmidth are also sponsoring the MEI Process Mineralogy '14 conference next year). Following Alice Clark's official opening, Dr Simon Dominy did a brief survey of the mix of delegates attending the conference: a fairly equal mix of geologists and metallurgists with a few mining engineers. Somehow as a process mineralogist, I felt that my own career interests weren't captured since although I have degrees in both geology and engineering, I feel like I sit somewhere in between these two disciplines and don't have a real identity within either one of them. I'd be interested to hear from other process mineralogists what they feel.

Geomet '13
The FLSmidth team
The first speaker of the conference was Professor Steve Begg who delivered the Pedro Carrasco lecture. Steve is the Professor of Petroleum engineering and Management at the Australian School of Petroleum at the University of Adelaide. His plenary Some reflections on uncertainty, decisions, models and people set the theme of the morning, focusing heavily on geostatistics. Steve noted a very real problem in industry in that the bigger and more important a project gets, the more likely it ends up in disaster. He talked through a variety of reasons as to why business outcomes are not living up to expectations: through gross under estimates and a naive understanding of NPV, as well as the fact that good decision making requires accurate estimates of uncertainty. He clearly clarified the differences between uncertainty and natural variation, in that uncertainty is a function of what we know. His underlying message to the audience was that the main role of the geoscientist / engineer is to support decision making and that technical work is aimed at uncertainty assessments to aid decision making.

The theme of geostatistics continued through the morning and after lunch there was a change of pace focusing more on the topics of ore characterisation and texture analysis. Professor Dee Bradshaw from the JKMRC (a consultant for MEI's Flotation '13 conference in Cape Town next month), gave a review paper on The influence of textural variation and gangue mineralogy on recovery of copper by flotation from porphyry ore co-authored by Al Cropp and Will Goodall. Dee's paper set a theme for the conference in noting how important texture is in geometallurgy. She also talked through the first principles of the theoretical grade recovery curve, whereby the mineralogy ultimately dictates the overall grade and recovery emphasising the nature of the relationship between grade and recovery. The theoretical grade recovery curve is probably one of the most useful contributions that has developed out of the field of process mineralogy and I always ensure that I expose my undergraduate and postgraduate students to this concept.

Geomet '13
Dee Bradshaw and Simon Dominy with JKMRC students
The afternoon continued through the theme of textures with some nice talks by Dr Julie Hunt from CODES at the University of Tasmania Estimating comminution indices through ore mineralogy, chemistry and drill core logging, as well as by Laura Perez-Baurneuvo on New perspectives on quantitative textural analysis. Laura is currently finishing up her PhD studies at the University of Madrid, Spain. I first met Laura at Process Mineralogy '12 in Cape Town at the end of last year where she gave one of the best presentations of the conference. Laura has developed some of her own textural indices that are centred on the use of linear intercepts and showcased using a case study from the Zambian copper belt.

Tuesday October 1st

Day 2 of the conference started with a keynote from Prof Karin Olson Hoal from the Colorado School of Mines discussing the importance of mineralogical inputs into geometallurgical programs. She started fairly light-heartedly with a cartoon on the Pyrites of the Caribbean as an illustration of the role of mineralogy with the poor mineralogist trying to defend himself by pointing out that the gold is in the pyrite. Her key message was to emphasize that the mineralogy is the quantification of ore body variability and this needs to be incorporated into financial models for project variability.

The second keynote was delivered by Steve Williams from GEOMET Tech in Canada: A historical perspective of the success of geometallurgical methodologies. Although somewhat controversial as to when the history of geometallurgy actually started, he did emphasize the need that people of multiple skills need to work together, and that often geomet just requires pure long term commitment from those involved in building and refining a geometallurgical model and believing it will provide long term value, even in cases where the model indicates that the deposit will not be economic. Once again, the theme of ore variability came through in that "there is no such thing as an average ore body".

Geomet '13
Aukje Benedictus (left) of FEI demonstrating the new mine site automated mineralogy
The rest of the day provided an interesting mix of case studies on gold, PGMs, uranium, iron ore, and copper; as well as the development of various methodologies as indicators of geometallurgical performance be they from actual physical tests (BWI, flotation indicator, leach performance) or from actual mineralogical and chemical data (e.g. the mineralogical approach of Prof Pertti Lamberg from Lulea University of Technology in Sweden). Caroline Johnson from CSIRO in Australia delivered a very articulate and interesting presentation on the microscale characterisation of pristine and processed calcrete hosted uranium ore that showed the need for a thorough understanding of ore forming processes when interpreting hydrometallurgical extraction.  

The conference dinner was held on Tuesday evening, and provided a good break from the formalities of the conference and a chance to catch up with old and new acquaintances to the backdrop of some light hearted live jazz.

Wednesday October 2nd

The third day of the conference continued on the theme of ore variability with a keynote delivered by Prof Malcolm Powell of the JKMRC, University of Queensland. Malcolm spoke on how the value of geometallurgy is not in the measurements and the data, but rather on how you use it and illustrated this by his vision of future mining where ore processing circuits leverage ore variability to maximise resource efficiency. This of course requires the ability to be able to model equipment and circuit performance with efficiency, which is the aim of his Research Chair in Sustainable Comminution. Malcolm's talk was followed by Dean David of AMEC Australia who spoke of how the Joint Ore Reserves Committee (JORC, managed through the AusIMM) now requires the reporting of geometallurgical information in mineral resources and reserve estimation. This is clearly an indication that geomet is here to stay and that geometallurgy is now becoming part of global best practise.

My favourite talk of the conference was delivered by Michelle Sciortino from Royal Nickel Company who gave the best example of geometallurgy in practise in her talk on the geomet modelling of the Dumont nickel deposit in Canada. Michelle clearly showed the integration of mineralogical and metallurgical information in the geometallurgical model, and how it has been continually refined to account for the mineralogical complexities of the Dumont deposit.

Last but not least, the conference concluded with some talks on the need for incorporating acid rock drainage (ARD) indicators into the geometallugical model. As we continue to process more mineralogically complex ores, so we need to be thinking about ARD upfront when designing the operation. Ultimately, we should be thinking about ways of removing ARD upfront rather than late stage treatment with lime addition.

After the awards of the best young presenter prizes to Caroline Johnson from the CSIRO (best local presentation) and Michelle Sciortino from the Royal Nickel Company (best international presentation), Dr Simon Dominy gave his closing conference remarks. Simon spoke of how the challenges for geomet in the future will be to ensure that the geomet approach gets embedded in practise, ensuring correct sampling and testing methodologies especially on small scale samples, reducing mineralogical uncertainty and designing plants for ore variability. The 3rd GeoMet conference is planned for early 2016. 

No comments:

Post a Comment

If you have difficulty posting a comment, please email the comment, and any photos that you might like to add, to bwills@min-eng.com and I will submit on your behalf