Friday, 29 March 2013

How photography has changed!

Here's a blast from the past. We were doing a little spring-cleaning today and came across this 1969 press cutting from a local Manchester newspaper.

B.A. Wills 1969

From the age of 16 I worked as a part-time freelance photographer, and during my time at University spent my weekends supplementing my meagre grant by covering sports events for the local paper.

A few weeks after this photo was taken, Barbara and I were off on our great adventure, and the start of a wonderful life in the minerals industry.

B.A. Wills 1969
Approaching the Rhodesian border, September 1969
The camera that I used in the 1960s was a Rolleicord V. The more expensive Rolleiflex was out of my league then, although I now own one despite it being redundant. The twin-lens Rolleis used roll-film, with 12 photos on each roll, so after an afternoon at the football ground I returned to the darkroom to develop the rolls and then make prints from the negatives.

It was a slow and laborious process, and how things have changed with the advent of modern digital cameras. But I have to admit that I still miss the black and white images slowly emerging from the developing solution under the warm orange glow of the darkroom lamp!

Wednesday, 27 March 2013

Flotation research - does advancement require a paradigm shift?

Flotation has been a technology success story in providing metals and industrial minerals for mankind. Much of the technology development has taken place by industrial experience and trial and error. As the ore-base keeps changing, new challenges are arising. Lower grades require high volume throughput flotation technology for economy; more complex ores require the capability to handle finer feeds efficiently. Faster development will be needed as issues of material efficiency, use of water and tailings quality are becoming crucial for the acceptance of the industry.

After a century of research we are still struggling to fully understand flotation. There are several reasons for this, which will be discussed by Prof. Kari Heiskanen, of Aalto University, Finland, in his keynote lecture at Flotation ’13 in November.

The combination of two discrete phases in a turbulent continuum has proven to be full of challenges. Phenomenological models, embodied in the first order rate model and all derivatives thereof have, in Prof. Heiskanen’s view, come to the limits of their usefulness. We can and should use them to solve many practical issues where work can be based on laboratory experiments, but they will not give us any further understanding of the underlying physico-chemical phenomena involved. This understanding is needed, if we wish to develop new generations of effective flotation cells and processes.

Prof. Heiskanen will discuss the need to span research over several decades of scale, instead of working mostly on continuum scales. The momentum effects are multidimensional already in the continuum scale. The crucial point discussed will be the transfer of continuum momentum effects via the boundary layers to the molecular scale at these boundaries and the effects of boundary molecular structure to the continuum behaviour. This will be discussed in the light of a frother and bubble system. He will also refer to ideas of creating true multi-physics models for flotation. In doing so, some areas needing a deeper understanding will be identified and discussed.

What are your views on the future of flotation research?

Monday, 25 March 2013

A mining pilgrimage for Physical Separation ’13 delegates

The birthplace of modern mining. This is what I have often called the Camborne-Redruth area of Cornwall. In the 19th century this was the world's largest producer of copper and tin. With the decline of the mines, due to the discovery of large deposits of tin in Malaysia and copper in the Americas, Cornish miners took their expertise to all corners of the world, leaving behind a heritage and industrial archaeological landscape second to none.

Everyone in the mining industry should make a pilgrimage to this fascinating part of the world, and delegates at this year’s Physical Separation ‘13 conference will have the opportunity to do just that.

Last Friday Barbara and I attended a Camborne School of Mines (CSM) reunion at the King Edward Mine Museum near Camborne. This is without doubt one of the best mining museums in the world, particularly as far as mineral processing is concerned, and this is in no small way due to the dedication of Tony Brooks, ex-CSM mining lecturer and Tony Clarke ex-experimental officer at CSM. I worked closely with Tony Clarke in the 1970s to develop the CSM Pilot Plant and his enthusiasm for that project has obviously carried over to the KEM Mill, which simulates a late 19th century processing circuit, complete with working stamp mills, buddles, round frames, rag frames, Frue vanners and shaking tables.

Tony Clarke explains the principle of the rag frame
Preparing a vanning assay
Delegates at Physical Separation ’13, and accompanying partners, are invited to a tour of the historic Camborne-Redruth mining area in the late afternoon of June 21st. After a coach drive to Camborne, passing the South Crofty Mine, the last of the tin mines to close, we will commence the tour with a visit to the KEM Mill, to see the old gravity devices in action, before driving to the Basset Mines in the heart of the district (see posting of 12 June 2011 for a full description of the Basset Mines).

West Wheal Basset
Don’t miss this trip if you are attending the conference! Take a look at photos from the Physical Separation ’11 tour.

Wednesday, 20 March 2013

An invitation to a workshop for journal authors at Flotation ‘13

Flotation ’13 in November is the conference not to miss if you are involved in any way with flotation. Already all the exhibition booths have been sold, and companies from around the world are supporting the event.

The deadline for abstract submission is the end of June, and we look forward to a very full 4-day programme of papers from leading international specialists. We also expect, and encourage, papers from young researchers just starting out on their careers in this, arguably the most important unit operation in the minerals industry.

Authors of all papers will be invited to submit their manuscripts to Elsevier’s Minerals Engineering after the conference, for review and possible publication in a special flotation issue of the journal in 2014.

Preparing a good journal article is very much an art, and on 17 November from 14.00 to 16.30, the publishing company Elsevier will run an author workshop as part of Flotation ’13 at the conference venue, the Vineyard Hotel in Cape Town.

There will be two modules:

(1) How to get Published in a Research Journal and

(2) Author’s Rights and Responsibilities.

The first module will take around 90 minutes including questions and answers and will be presented by Dean Eastbury, Executive Publisher for Chemical Engineering at Elsevier and Professor Jochen Petersen, Department of Chemical Engineering, University of Cape Town and Editor-in-Chief of the Elsevier journal Hydrometallurgy. The second module takes about 45 minutes and will be presented by Dean Eastbury, who will also show a short video explaining The Article of the Future.

The workshop is aimed at people who are relatively inexperienced with publishing in research journals but expect to do so frequently in the future. If you are either a postgraduate student or young lecturer working in physical science research and would like to attend, please contact Dean directly at The workshop is entirely free of charge.

Immediately following the workshop is pre-registration for Flotation ’13 and a chance to relax and meet other delegates at the opening wine reception.

Wine reception at Flotation '11

Monday, 18 March 2013

New E-Book: Ni-Co 2013

With both nickel and cobalt featuring heavily in modern industry, there is an ongoing and intense interest in ore supplies and processing, applications development, and recycling. This e-book presents a collection of authoritative papers covering the latest advances in all aspects of nickel and cobalt processing, including fundamentals, technology, operating practices, and related areas of Platinum-Group Metals (PGM) processing. Special emphasis is given to the treatment of sulphide and laterite ores, concentrates, and secondary materials for the production of nickel and cobalt.

Ni-Co 2013 is edited by Thomas P. Battle, Michael Moats, Violina Cocalia, Harald Oosterhof, Shafiq Alam, Antoine Allanore, Rodney Jones, Nathan Stubina, Corby Anderson, Shijie Wang and is published by Wiley. It can be ordered directly from the publisher.

Thursday, 14 March 2013

Where is comminution going?

Last year at Comminution ’12 I opened the conference by discussing the quiet revolution which has taken place in comminution.

For most of last century there had been little development in comminution machines and circuits, cone crushing being followed by ball milling, rod mills sometimes acting as tertiary crushers. In the latter part of the century, however, autogenous and semi-autogenous milling became more prominent, and then high-pressure grinding rolls began to play an ever increasing role, as did stirred mills, the latter allowing the exploitation of ultra-fine grained ores which had hitherto been impossible to economically treat.

This revolution continues, so that comminution circuits today are very much different to those of the mid-20th century with their parallel lines of small ball mill-cyclones.

Typical 20th century ball mill circuit
The rod mill is almost an obsolete device, and I asked the question at Comminution ’12 whether ball mills would play a significant role in comminution circuits, or would they be superseded by SAG mills. Chris Rule, of Anglo Platinum felt that rod mills will play an insignificant role, as they are severely limited in terms of size, and ball mills may play a diminishing role as the upper feed size range of stirred mills increases.

This is interesting as last month at the SME Meeting in Denver I was discussing this with someone, I can’t recall who it was, who had heard that many operations were having to increase the proportion of steel balls in their SAG mills in order to improve performance, effectively converting them slowly back to ball mills.

So what are your opinions on this? How do you see future comminution machines and circuits evolving. Does the future lie with HPGR and stirred mills? These are all subjects which I hope will be discussed further at next year’s Comminution ’14.

Friday, 8 March 2013

Can Power be Consumed?

I may be being pedantic, but a phrase commonly seen in the media, and also in scientific journals is ‘power consumption’.

Can we consume power, or is power a means of creating energy (and vice-versa)?

In other words, should the correct phrase strictly be ‘energy consumption’.

Your advice sought.

Wednesday, 6 March 2013

The MEI Award to an outstanding young person

I met many interesting people at last week’s SME Annual Meeting in Denver. It was particularly good to meet, for the first time, Randy Zahn, of FLSmidth, USA, and to give him the good news that he is the recipient of the 2012 MEI Young Person’s Award. His very impressive citation is on MEI Online.

With Randy Zahn in Denver
This is the second time that the award has been made. Last year the winner was Peter Amelunxen.

Randy will be presented with the award at Physical Separation ’13 in Falmouth in June.

A call for nominations for the 2013 award will be made in December, so now is a good time to start thinking of nominating an outstanding young person who has made a significant contribution to mineral processing.

Sunday, 3 March 2013

SME 2013 A mineral processor's view

It is good to be back in Denver for what is one of the world's great minerals industry meetings. There is something for everyone here; in fact maybe too much for everyone, with the usual head-spinning number of parallel sessions, the huge exhibition, as well as receptions, awards, workshops and dinners. Mineral processing is only a small part of the overall proceedings, but even so I can only scratch the surface, and this report is very much my diary of personal experiences, which I hope will be supplemented by the input of others who attended.

Sunday February 24th
After nine days acclimatising in the mountains, Barbara and I arrived in Denver this morning via the Colorado Mountain Express. The road conditions were atrocious, and Denver itself is in the grip of a raging snow storm.

16th Street Mall, Downtown Denver
After registration we attended the official opening of the exhibition, and I thank John and Donna Starkey for loaning one of their exhibitor passes to Barbara so that she could accompany me for the 2 hour session.

Barbara with Donna and John Starkey, of Starkey & Associates, Canada
According to a tweet from the SME (@smecommunity) there are 585 exhibitors this year, a sizeable increase on last year's event in Seattle, but the opening was a relatively quiet affair, probably due to the snow, which has caused severe disruption of flights into Denver.

Monday February 25th

SME's resident tweeter,
Heather Gravning

The skies have cleared, the flights are back on schedule, and people are flocking in to register. Over 6800 have registered according to the tweets from @smecommunity, making this the largest ever SME. I arrived at 9am but not a lot happens on the first day of an SME and the exhibition does not open until 11am.

So the first port of call was to the Bookstore to see what is new this year. There was only one new book related to mineral processing, Process Plant Equipment, edited by Holloway et al and published by Wiley. This is a reference book for final year students as well as those who will work, or are working in production plants and refineries. It contains the information and practical guidelines needed to select, operate, maintain, control, and troubleshoot process plant equipment so that it is efficient, cost-effective, and reliable throughout its lifetime.

Guven Onal and Jim Finch
It was good to see old friends Prof. Jim Finch, of McGill University, Canada, and Prof. Guven Onal, of Istanbul Technical University by the Bookstore. Jim and I spent some time discussing a new project which we hope to be collaborating on. More on this at a later date. Also outside the Bookstore I met Romke Kuyvenhoven of Gecamin, Chile and we discussed MEI's involvement with Procemin '13 and next year's IMPC in Santiago, which will be organised by Gecamin. Romke will be presenting a short video this afternoon promoting the IMPC, and this can also be seen on YouTube.

Then into the exhibit hall, which as always is dominated by the huge FLSmidth display.

FLSmidth is a world leader as a source of engineered mineral processing equipment, systems and services and are major sponsors of MEI Conferences, and I called in to say hello to the many familiar faces, including Director of Global Marketing Andrew Cuthbert.

With FLSmidth's Andrew Cuthbert
I also called at the Metso booth, to thank them for their recent sponsorship of Comminution ’14. Metso provides a range of services to the minerals industry, including life cycle services, spare and wear parts replacement, field services, preventive maintenance, automation solutions, plant diagnostics, equipment refurbishment, as well as a broad range of training courses.

Before heading off for lunch I dropped in at Outotec, another major company providing a broad spectrum of services, including comprehensive processing plant solutions based on decades of research and development in its own research facilities and former plants. They are major sponsors of this year’s Flotation ’13 conference in Cape Town.

The mineral processing presentations commenced in the afternoon with the prestigious SME Award lectures. The highest award bestowed is the Antoine Gaudin Memorial Award and this year the recipient was Prof. Graeme Jameson of the University of Newcastle, Australia. Well known for the development of the successful Jameson Cell, first used at Tennant Creek in 1990, Graeme has in no small way contributed to improving the knowledge and hydrodynamics of flotation. His lecture Adventures in Flotation highlighted how flotation is a difficult art which is gradually yielding to science and informed observation.

The Richards Award lecture Making Simple Processes was presented by Nick Hazen, President and CEO of Hazen Research, USA who discussed how innovation is necessary for sustainability of future mining operations. These processes should be as simple as possible, such as innovative HPGR, bioheap leaching etc.

Prof. Jan Miller of the University of Utah, presented the Wadsworth Lecture on X-ray tomography for the 3D analysis of hydrometallurgical systems, a follow-on from his excellent keynote presentation at Process Mineralogy '12 (see also the posting of 16th August 2012).

Jan Miller, Nick Hazen and Graeme Jameson

Tuesday February 26th
The Symposium on Innovation in Metallurgical Processing got underway this morning, with Innovations in Comminution, and Innovations in Smelting running in parallel. Fair enough, but also running in parallel with these were sessions from the Mineral and Metallurgical Division (MMD) on Flotation; Plant Design and Optimisation; and Research and Characterisation. Frustrating to say the least, but having spent many years at SMEs I have learned to live with this and accept that the strength of the SME is mainly as a meeting place, so I gain most value by wandering round the exhibition.. The lecture room for this morning's comminution session was heaving, however, testament to the interest in this area, and the very high quality speakers who are presenting. By contrast the smelting session was lightly attended, reflecting more on the fewer number of researchers in this field.

In the comminution session Wolfgang Baum discussed recent innovations in process mineralogy and laboratory automation, a follow-on from his keynote at last year’s Process Mineralogy ’12. Automated mineralogical systems are becoming increasingly used in operations treating low grade and ever more complex and refractory ores. FEI is the world's largest supplier of automated mineralogical electron microscopes, and were sponsors of the last Process Mineralogy conference. The company has recently acquired Visual Sciences Group (vsg) whose software allows 3-D visualisation of mineralogical data.

There are many bewildering session clashes to come over the next few days, none more so than this afternoon. The Innovations in Separations session was extremely well attended. All the papers dealt with innovations in flotation - reagents, modelling, plant practice and surface chemistry. I felt sorry for the speakers in the session on Flotation which ran in parallel, and was attended by fewer than 20 delegates. Unbelievably, also running in parallel was a session on Problematic Non- Sulfide Gangue Minerals and Their Detrimental Effects in Flotation Performance. When I looked in at this one, there was an audience of 6 people! Not great if you have traveled all the way from Australia to present, as had two of the speakers.

The flotation reagent manufacturers were out in force in the exhibition, including Flotation ’13 sponsors Cytec and Clariant.

As flotation machines now tend to be gigantic, there were none of these on display, but there were a number of very large pumps on view. It was good to see Watson-Marlow represented, as their head office is just around the corner from my home in Falmouth, UK. Their pumps are well known for pumping harsh fluids in the minerals industry.






It has been a full and enjoyable day of meeting old friends and new people, rounded off nicely with a late afternoon international reception at the Hyatt Hotel for non-USA participants. In the photo below is Prof. J-P Franzidis, of the University of Cape Town, South Africa, and consultant to Flotation '13; Dr. Patrick Foster, lecturer at Camborne School of Mines, UK; and Dr. Zafir Ekmekci of Hacettepe University, Turkey's representative on the Editorial Board of Minerals Engineering.

It was also good to catch up with Mike O'Driscoll and Laura Syrett of Industrial Minerals, UK, and to congratulate Mike on winning 3rd prize in the SME photographic competition. Industrial Minerals is a media sponsor for three upcoming MEI Conferences. Mike and Laura are pictured below with Louis Bernard of Snowden Consultants, Canada.

Wednesday February 27th
More frustrating clashes in this morning's parallel sessions. Comminution II was reasonably well attended, as was Modelling and Simulation, Innovations in Hydrometallurgy and the student poster session, but there was only about a dozen people in the Phase Separations session.

The most well attended was Separations Innovation II which featured a paper by Bo Arvison on ore sorting, perhaps the oldest method of concentration. Automated sorting is increasing in importance with the development of faster sensing technology. In addition to providing likely economic benefits it also has the potential to reduce the greenhouse gas footprint of mining and mineral processing operations, as shown by Norgate and Haque in the latest issue of Minerals Engineering (Volume 42, 2013). In yesterday’s Innovations in Comminution session, Jens Lichter discussed the future of comminution, the main challenges being reduction in energy consumption, and how preconcentration using sorting will become ever more important in reducing the tonnages treated in comminution.

Ore sorting will be a major feature of Physical Separation ’13 in June, and one of the sponsors of this event is TOMRA Sorting, previously known as CommodasUltrasort. Worldwide over 200 TOMRA sorting systems are already contributing to more energy efficient and cost effective preconcentration.

TOMRA Sorting
As well as a TOMRA paper on chromite processing, the Physical Separation ’13 programme also includes two papers from Australia’s JKTech on the next generation sorters and the development of indices to assess sorting potential and the performance of sorting processes. Papers from the JKTech will also examine a novel separation method, dielectrophoresis.

Continuing with the theme of dry separation, I stopped off at the Separation Technologies LLC (ST) booth. ST is a developer and provider of specialized processing technologies for beneficiation of dry fine particle materials. Founded in 1989, ST capitalized on proprietary technology to develop a unique processing system based on triboelectric charging and electrostatic separation. The environmentally friendly process eliminates wet processing, requires little if any pre-treatment of the material and operates at high capacity - up to 40 tonnes per hour. The ST belt separator is ideally suited for separation of very fine  (less than 1 micron) to moderately coarse (300 microns) materials with very high throughputs. The US based company has deployed many separators, in North America, Europe and East Asia. 

Separation Technologies

An interesting paper in this morning’s Phase Separations session discussed Hawk Measurement Systems latest findings on the use of acoustic sonar technology for measuring the compact zone or bed level as well as the interface or hindered layer in thickeners.

Hawk Measurement
A level probe for a different application, flotation bank pulp level control, was demonstrated at the Zeroday Enterprises booth. Monitoring flotation bank pulp levels with the standard ultrasonic/floating ball assembly is often very unsatisfactory. At many operations any improved pulp level monitoring and control will significantly increase grades and recoveries. The innovative LTM level probe dramatically increases pulp level measurement accuracy, which operates conductively and provides near instantaneous measurements (100 ms) with 1% accuracy and measurement linearity.

Zeroday Enterprises

After an excellent three days, the finale, the Mineral and Metallurgical Division Luncheon was something of an anti-climax, dominated by an interminable after-lunch lecture. But it was good to see the students awarded the Richard Klimpel Scholarships by Jim Metsa, the Chairman of the Scholarship Committee. They are pictured below, but unfortunately I did not have time to add names to faces.

Other awards were the Outstanding Young Engineer Award to Lisa Schlink and the Arthur Taggart Award for best scientific paper to Jason Ripke and Glen Hoffman.

The final act was handing over the chairmanship of the MMD for the next year, from Jason Ripke to Corby Anderson of the Colorado School of Mines.

Jason Ripke and Corby Anderson
I have had a very enjoyable time in Denver, and would thoroughly recommend the SME as a great networking event. In an event of this size there will always be some aspects open to criticism. My only real criticism, however, would be with the timetabling of technical sessions and the MMD really must look at this so as to avoid the frustrating clashes which have occurred, which led to some sessions barely attended.

This has been the largest SME ever, which is a measure of the confidence in the industry at the moment. I hope that this continues, and look forward to being in Salt Lake City next year for what we hope will be an even bigger and better SME. Congratulations to all concerned on the organisation of SME 2013.