Process Mineralogy '12 Conference Diary

Process Mineralogy '12 was held at the Vineyard Hotel, Cape Town, from November 7-9, 2012. The following is my diary of events, which, as always, I hope will be supplemented by comments from delegates who attended.


Conference sponsors

Wednesday November 7th
This morning I welcomed the 123 delegates from 21 countries to Process Mineralogy '12. This is the second conference in this series, and despite the recent problems on the South African mines, has attracted a record attendance and nine sponsors. This is not surprising, as process mineralogy should be of major interest to every modern mineral processor.

Three months ago I spent a day on the Nchanga mine in Zambia, my first visit since I left there nearly 40 years ago. While discussing the operations with the metallurgical staff I was interested to hear that the main copper losses from the mine were due to chalcocite. Why this was particularly interesting was that 40 years ago, despite the broad suite of minerals in the ore, there would have been no mention of a mineral, all losses being reported by chemical assay as acid soluble or acid insoluble copper. Process mineralogy was something which apparently did not exist- we did not even have a microscope on the concentrator.

Now that ores have become more complex and refractory, knowledge of process mineralogy is essential on every mine, and the tools with which we analyse the behaviour of mineral assemblages have by need become increasingly sophisticated (and expensive!). So we have a lot to look forward to over the next three days, with case studies from various operations, the emergence of new technologies, such as tomography, and the continued development of geometallurgy, the science of integrating geology and mineralogy with mineral processing and extraction.

With Megan Becker

Following my brief introduction, I had the great honour of presenting the inaugural MEI Young Person's Award to Peter Amelunxen (posting of November 7th), before introducing our process mineralogy consultant, Dr. Megan Becker, of the University of Cape Town. She talked about the changes that are taking place in the process mineralogy community and how we are generally moving in the right direction. There are some really exciting developments in the world of x-ray tomography that should enable us to really get to grips with things like routinely imaging particles in 3D, measuring coarse particle liberation, rapid scanning for minerals of interest etc.

This morning's keynote lecture, presented by Dr. Wolfgang Baum, of FLSmidth, USA, set the scene perfectly for the day's papers on process case studies. Entitled "Ore characterization, process mineralogy and lab automation - a roadmap for future mining" he looked at the upstream requirements of process mineralogy in the future. Some mineralogical and chemical laboratories are making the step change toward automation, but the use of automated mineral analysis and high-throughput mineralogical ore profiling in production requires a faster pace. Cross belt neutron analyzers, over-the-belt NIR and, eventually, on-line XRD systems will become important for competitive ore processing. The mines of the future may be outfitted with down-hole probes and on-site automated mineralogy modules. Robust and rigorous use of automated laboratories and cross-belt technology will be the new frontier for process mineralogy.

With Byron Bezuidenhout (South Africa), Musarrat Safi (South Africa),
Friederike Minz (Sweden) and Tobias Salge (Germany) who were presenting
papers for the first time at an international conference

The morning session continued with case studies on mineral processing operations including an extension of process mineralogy to the processing of waste.
After an excellent Vineyard lunch, the afternoon session was dominated by 4 case studies from Anglo American Technical Solutions, a major user of automated mineralogy systems. Of the other four papers, there was an interesting one from Norway on the effect of sulfides on the whiteness in paper production, highlighting how process mineralogy is diversifying.

Thursday November 8th
The rapid development in sophisticated mineralogical techniques was highlighted in today's papers, led by an excellent keynote lecture by Prof. Jan Miller, of the University of Utah, who set the scene by showing how X-ray tomography has progressed from the late 20th century to the present day. He stressed that appropriate education and training of young scientists in this area is necessary to develop the advanced skills for future development and applications. What is encouraging in this respect is the high proportion of young people attending the conference, which bodes well for the future.

It is only four years since our last annual Automated Mineralogy conference in Brisbane. At that time the only mineralogical SEMs generally available were the JKTech's Mineral Liberation Analyser (MLA) and Intellection's QEMSEM and QEMSCAN. Intellection went into receivership shortly after Automated Mineralogy '08 and QEMSEM/SCAN were taken over by FEI, who now also market the MLA.

The FEI booth

Conference sponsor FEI is a premier provider of electron- and ion-beam microscopes and solutions for applications across many industries. The company is displaying the recently introduced MLA EXpress™, a low-cost, bench-top, automated mineralogy analyzer that may enable the mining industry to maximize the recovery of valuable metals from the ore. MLA EXpress extends mineral liberation analysis to a broader scale of mining operations.

Major changes in recent years include developments in the technical capabilities of automated mineralogy and associated techniques, and the growth in the number of instrument manufacturers.

This is the first time that the Czech company TESCAN has attended an MEI Conference, and their sponsorship of this one highlights how they are building a reputation in designing, manufacturing and selling scanning electron microscopes and system solutions for different applications, currently having over 1300 SEM installations in more than 60 countries.

At the TESCAN booth

The TESCAN Integrated Mineral Analyzer (TIMA) is a new SEM-based automated mineralogy solution for the mining and minerals processing industries. TIMA measures mineral abundance, size by size liberation, mineral association and grain size automatically on multiple samples of grain mounts, thin sections or polished sections.

Oxford Instruments is another company sponsoring an MEI Conference for the first time. Building on more than 20 years of experience in Scanning Electron Microscope-based Mineral Liberation Analysis, the company is exhibiting INCAMineral, an Automated Mineral Liberation Analysis solution
for multipurpose SEMs. This combines the functionality expected from a dedicated automated mineralogy system with the flexibility of a SEM.

Oxford Instruments

Automated techniques for mineral classification, liberation analysis and textural analysis featured strongly in the afternoon session, which included a paper from Carl Zeiss Microscopy Ltd, presenting an SEM solution based on a fully automated mineralogical tool, MineraLogic, that performs the characterisation, classification and quantification of ash minerals. MineraLogic was on display at the conference and generated much interest. 

Demonstration of MineraLogic

After two intensive days it was good to relax with delegates at the Gold Restaurant in the city, for a very informal African themed conference dinner (see also posting of 9th November).

Friday 9th November
Geometallurgy was the theme of the 10 papers presented in this morning's session, which included two presentations on rare earths beneficiation from South Africa's Mintek and conference sponsor SGS.

The SGS booth

The final sesion dealt with the tools of process mineralogy. Prof. Johan de Villiers of the University of Pretoria showed that the most common methods for generating mineralogical information of relevance to the minerals and metallurgical industry are usually in the order: optical microscopy, XRD analysis and Quantitative SEM analysis. These are usually generated by persons skilled in one of these techniques. As a consequence, the results of the other techniques are often overlooked or neglected. He discussed the applicability of each of the methods and their strengths and weaknesses. Conference sponsors PANalytical and Bruker AXS presented interesting papers, the former showing how X-ray diffraction can be used for process optimisation, and Bruker how XRD, XRF and MLA have been combined to analyse an iron ore.

At the PANalytical booth

The Bruker AXS booth

Megan Becker and Amanda closed the conference, and invited delegates to attend Process Mineralogy '14, which will be held at the same venue from November 17-19, 2014. Then it was out into the sunshine for yet more wine
and final farewells.

All 57 papers presented at the conference are available on CD from MEI.