Wednesday, 31 August 2011

Blooming Falmouth

Queen Mary Gardens, Gyllyngvase Beach

There is more to Falmouth than a beautiful coastline, great restaurants and pubs. It also has some of England's most beautiful gardens, particularly those on the two rivers, the Fal and the Helford.

Last month Falmouth won a Gold Award in the annual 'Britain in Bloom' competition, and the Queen Mary Gardens, immediately in front of the MEI Conferences hotel, the Falmouth Beach, was voted the 'best in the west'.

Monday, 29 August 2011

Metallurgical Challenges Facing the Gold Mining Industry

This is one of the themes of next year’s Precious Metals ’12 conference in Cape Town, currently being sponsored by Implats of South Africa and Australia’s Gold & Minerals Gazette.

The gold industry is experiencing change. Ores are more complex metallurgically, grades are lower and there are stricter environmental regulations making it more difficult to bring on new viable gold projects.

So it is timely that Dr. Robert Dunne, of Newmont Mining Corporation, USA, will present a keynote lecture reviewing the current status of processes used in the gold industries (i.e. milling, gravity, flotation, leaching, cyanide destruction/recovery and water treatment) and highlight where advances are being made to make the gold industry more viable.

Over the last 30 years Robert has worked for a number of mining companies including Anglo American, Anglovaal and Newcrest Mining and also spent time at the Western Australian School of Mines lecturing and at Mintek where he was involved in introducing new technologies into the mining industry. He is a graduate of the University of the Witwatersrand, South Africa and is an Adjunct Professor at the JKMRC, Brisbane, Australia.

Thursday, 25 August 2011

Extractive Metallurgy of Nickel, Cobalt and Platinum-Group Metals

Elsevier has announced the publication of Extractive Metallurgy of Nickel, Cobalt and Platinum-Group Metals by Frank K. Crundwell, CM Solutions, South Africa; Michael S. Moats, University of Utah, USA; Venkoba Ramachandran, Ram consultants, USA; Timothy G. Robinson, Freeport-McMoRan Mining Company and William G. Davenport, University of Arizona, USA.

Nickel, cobalt and platinum group metals are key elements for materials processing. They map together on the periodic table, occur together in many ores and are natural partners for further materials processing and materials manufacturing. It is for this reason that next year’s Precious Metals ’12 and Nickel Processing ’12 conferences will be running back to back in Cape Town.

These metals are, for example, important catalysts - with platinum group metals being especially important for reducing car and truck emissions. Stainless steels and CoNiFe airplane engine super alloys are examples of practical usage.

The book describes and explains the methods by which three related ores and recyclables are made into high purity metals and chemicals, for materials processing. It focuses on present day processes and future developments rather than historical processes.

The book provides a detailed review of the fundamental chemistry and physics of extractive metallurgy with practical lessons from industrial consultancies at the leading international plants

Details are as follows:
Hardback / 610 pages; Print ISBN: 9780080968094; Print list price: $189.95/€139.95/£119.95; Electronic ISBN: 9780080968100

Sunday, 21 August 2011

Around Port Isaac

Port Isaac harbour
Cornwall never fails to amaze and delight. Today we drove the 45 miles from Falmouth to the picturesque north coast fishing village of Port Isaac. Also known as the fictional "Portwenn" it is the setting for the long running TV comedy drama series Doc Martin.

Its narrow steep streets are bustling with tourists at this time of year, and we caught a glimpse of Prime Minister David Cameron taking some time off with his family.

A steep climb from the small harbour transports you into another world, where you see scarcely a soul and the only sounds are the soaring gulls and the crashing waves below the 75 metre high cliffs.

The scenery is simply stunning and the walk from Port Isaac to Port Quin was a hard one and a half hours of 'snakes and ladders' with the coast path plunging many times down to the tiny coves and rocky inlets before rising steeply again to the cliff top.

Port Quin
Wearily arriving at Port Quin we had a quick stop for refreshments before returning to Port Isaac on relatively easy inland footpath.

This is a day out from Falmouth that I would highly recommend to our visitors, providing that you have your own transport, and that you are fairly fit!

More Cornish Walks
More on Cornwall

Should laptops be banned from conference sessions?

Conference rooms are set up either as 'theatre (cinema) style' or 'classroom style'. The latter, which gives delegates the luxury of a table or desk, has become accepted without question as the better option, as it allows easy use of a laptop for making notes, viewing Proceedings papers etc.

MEI Conferences has always strived to go for the classroom option, but I am beginning to have doubts as to whether this is the better option. When I do sit in on a conference paper (rarely), I usually sit at the back and I have noticed that many of the delegates using laptops are more likely to be checking emails and browsing the web than concentrating their attention on the contents of the presentation.

Which leads me to ask, should laptops be banned, rather than encouraged, from conference sessions, and would theatre style then be the optimal setup?

Your comments on this will be very valuable.

Tuesday, 16 August 2011

ICAM '11 Conference Diary

Dr. Megan Becker
ICAM 2011, the 10th International Congress for Applied Mineralogy, was held in Trondheim, Norway, early this month. MEI was represented at the event by Dr. Megan Becker, of the University of Cape Town, and consultant to next year’s Process Mineralogy ’12.

Following is Megan’s conference diary, which I hope will be supplemented by comments from delegates.

Monday 1st August
Today marked the official start of the 10th ICAM, organised by members of the Geological Survey of Norway (NGU).

Radisson Blu Garden Hotel
The conference venue is the Radisson Blu Royal Garden Hotel overlooking the River Nid. There are over 150 delegates from 30 different countries represented at the conference, where 96 peer reviewed posters will be presented as papers and guided poster sessions.

Maarten Broekmans
The conference was officially opened by Dr Maarten Broekmans from NGU who is the Chief Editor of the Conference. Congratulations should go to the organising committee for persevering with the conference, despite the recent attacks on Friday 22nd July in Oslo. A minute of silence was given to remember those lost in the attacks at the ice breaker function last night which consisted of drinks followed by traditional Norwegian seafood soup and rolls which were heartily enjoyed by all.

Ying Gu (right) with Anglo American delegates
Chris Rule and Robert Schouwstra
Dr Ying Gu from the Julius Krutschnitt Mineral Research Centre in Brisbane, who is the current Chairman of the International Congress for Applied Mineralogy then added his words of welcome to the conference. He also congratulated Dr Dick Hagni from the Missouri University of Science and Technology, in Rolla, USA, who has attended all 10 ICAM conferences since the first conference held in Johannesburg, South Africa in 1981.

The 1st keynote of the conference was given by Jan Cramer from the Geological Survey of Norway on “The Northern Frontier – future mineral resources of the Arctic and Sub-Arctic”. Jan introduced his talk by reminding us all of the current need for mineral resources especially in countries such as China which want to raise their standard of living. Jan then methodically went through the mineral potential of Alaska, Canada, Greenland, Russia, Svalbaard and Fennoscandia (Norway, Finland and Sweden). He focused on some of the current challenges within these areas such as the need for more exploration particularly in deeper areas requiring the use of deep geophysics and drilling, improved processing technology, environmental challenges associated with mining within the Arctic and Subarctic, areal conflicts particularly with people native to these areas, the lack of regional infrastructure, and the distance to the markets. His keynote was particularly enlightening and refreshing for those of us focused on mining and mineral processing activities within the arid and semi arid regions of South Africa and Australia which also present their own set of challenges, particularly with respect to water shortages.

The 2nd keynote of the conference was given by Roelof Schuiling from the University of Utrecht on “Climate change and ocean acidification: Two problems – one solution”. Roelof started his keynote by noting that rising CO2 is probably associated with climate change, but is certainly associated with ocean acidification. He noted that this can either by controlled by adding a base, or removing the acid, two processes which Mother Nature has being doing herself for the last 4.6 billion years through the formation of dolomites and limestones (e.g. White Cliffs of Dover) and through the natural carbonation of olivine to listwanite (a carbonate altered serpentinite) in peridotites (e.g. Oman). Of the many (over 50) somewhat quirky uses which Roelof has for olivine, his focus was on the role of olivine on beaches and tidal flats where natural lugworms can increase the weathering / alteration rate of olivine by up to 1000 times. His keynote definitely caused some lively discussions, just indicating how topical the idea of natural or even engineered mineral carbonation is as a potential means of sequestering anthropogenic CO2.
Relaxing during a coffee break
The afternoon sessions of the conference held a change of pace with a session on geometallurgy as well as a parallel session on Process Mineralogy characterisation – two particular areas of relevance to anyone with an interest in process mineralogy and geometallurgy. Unfortunately one was quite torn deciding which session to attend, and brings to mind many of the old arguments against running parallel sessions at conferences. I know that MEI has always had very strong views on this. Given that I was presenting my own talk “Effect of alteration on the mineralogy and flotation performance of PPM platinum ore” in the geometallurgy session, I elected to stay in this session. Other talks of interest in this session was one by Prof Dee Bradshaw (JKMRC) on the “Role of process mineralogy in identifying the cause of the low copper recovery of chalcopyrite a Kennecott Utah copper mine” which was based on the work she did as part of her sabbatical with Rio Tinto in 2007. Dr Rob Schouwstra from AngloAmerican also presented his paper “Process Mineralogy delivering significant value at Anglo Platinum concentrator operations”. This paper was just another reminder of how important process mineralogy is in mineral processing and was backed up with a case study from their Amandelbult operation showing how process mineralogy has gone hand in hand with the implementation of fine grinding.

Tuesday 2nd August
Tuesday’s sessions were mostly focused on building and mineral materials and illustrates how the focus of the European Research Community differs from those rooted in Mineral Processing. With a guilty conscience I have to admit to taking an opportunity to slip out of the sessions and appreciate the sunny, warm Trondheim summer weather and join in the spirit of their annual St Olav’s festival. The city streets of Trondheim are alive with activity in the form of numerous stalls, musicians, a medieval market, a variety of jazz, rock and classical concerts celebrating King Olav Haraldsson, Norway's patron saint who reigned from 1015 - 1030.

Poster displays
The afternoon consisted of a “guided poster session”, a fairly novel concept to me. Each presenter was given 1 minute to do a summary of their poster, after 1 minute the coordinator rang the bell and the audience moved onto the next poster. Once the audience had established what was required from them, this turned out to be a great way to get exposure for your poster, and also allow you to get a snapshot of the work presented in parallel sessions which one might not have had the opportunity to attend. Possibly this idea should be considered in future MEI Conferences although one definitely needs to keep the noise levels down and ensure the audience cooperates.

Wednesday 3rd August
Wednesday held another interesting day of varied talks in the areas of Environmental Mineralogy, Geometallurgy and Image Analysis. Prof Dee Bradshaw, MEI's consultant to Flotation '11, was the first presentation of the day with her talk entitled “The development of a textural acid rock drainage index (ARDI) for predicting acid formation”. This was followed by Dr Dogan Paktunc from CANMET who spoke about “Sulfide oxidation and mobilization of arsenic in the Ketze River mine tailings”. Dogan gave a detailed characterisation of the arsenic bearing minerals and their As speciation, which have formed in these 20 year old mine tailings in Canada which have on average ~ 4 wt % As. His talk focused on the relative dissolution rates of the different arsenic minerals and whether an engineered approach can be used to promote the formation of the more inert As bearing minerals as a long term solution to managing ARD.

During the afternoon session on image analysis, Rogerio Kwitko-Ribeiro from VALE in Brazil presented some novel sample preparation methods involving centrifuging for automated SEM analysis to deal with the long standing issues of segregation during the preparation of particulate samples. Rogerio’s proposed methods are definitely worth consideration given the absolute necessity to have good data reconciliation in process mineralogy otherwise one spends hundreds or thousands of dollars on quantitative mineralogy for which the results aren’t even representative. This was followed by another interesting talk given by Pejman Oghazai from Lulea University of Technology in Sweden comparing the results of a mineralogical characterisation of iron ore using the particle texture analysis (PTA) software developed by the Norwegian University of Science and Technology (based on Oxford INCA hardware) with QEMSCAN (based on FEI hardware). Possibly another interesting development worth keeping an eye on for the automated mineralogical community...

Thursday 4th August
Thursday was probably the best day of the conference, consisting of a great geometallurgy session in the morning, a visit to the Nidaros Cathedral in the afternoon, followed by the conference dinner.

Undoubtably the most interesting talk in the morning session was given by Mike McDonald from Rio Tinto “Learnings from 5 years on-site MLA at Kennecott Utah Copper Company: Myth busters through quantitative evidence”. Mike showed that for many years the plant had been run on “mythical information” (e.g. a single analysis of a gold grain), and how plant operators were slow to accept the new quantitative mineralogical information derived from the MLA, even though the results were based on the analyses of millions of particles over several years. However, once the operators began to accept the value of the MLA results, positive changes could be implemented on site resulting in significant gains to the company. Another interesting talk of the session was given by Dieter Rammalmair from BGR in Germany showing once again the value of combining 2D MLA information with 3D micro tomography information. The complete integration of 2D and 3D mineralogical datasets will surely become one of the major milestones for process mineralogy in this decade.

The afternoon session consisted of a technical visit to the Nidaros Cathedral which was about a 15 minute walk from the conference venue. The Nidaros Cathedral and neighbouring Archbishops Palace (that hosts the Norwegian crown jewels, and is still used for official royal banquets) are the centre of the cultural history of Trondheim. In addition to the fact that the Nidaros catherdral is over 1000 years old and is built over the grave of their patron Saint, St Olav; it is made from soapstone. This would make it one of the worlds’ largest man-made constructions of naturally floating gangue, i.e. talc! I particularly enjoyed the opportunity to split up into smaller groups and wander around the site at ones leisure.
Visiting the Nidaros Cathedral
The conference banquet was very enjoyable occasion with a strong Norwegian theme. The dinner consisted of traditional Norwegian cuisine, which included reindeer steak. The evening’s entertainment consisted of the “Mineral Quintet”. Conference delegates enjoyed being serenaded with a variety of musical items from Mozart, Greig (who was Norwegian), and even begrudgingly music from the famous Swedish Abba. One of my lasting impressions of Norway which I will take home is the realisation just how much music means to them, and how it probably has helped them survive the many long winter days and nights over the last few centuries.

The evening concluded with the announcement of the venue for the next ICAM conference, which will be held in Mianyang City in China, from 21-29 July 2013. The conference is to be organised by Prof Faqin Dong from the Southwest University of Science and Technology in the Sichaun Province. It promises to be a very exciting venue for the conference, and we wish the organising team good luck for the next 24 months as they prepare for the conference.

Friday 5th August
Delegates from FEI
Friday was a relatively disappointing day for the conference and only consisted of 2 papers and then a “Summary and Review” panel discussion. David Haberlah from FEI did however give a very interesting paper on the application of automated mineralogy (QEMSCAN) in reconstructing microlithology of rock types from drill cuttings derived in the oil and gas industry. Surprisingly this was the only paper of the conference on oil and gas, even though there are many new and sophisticated techniques routinely used in this industry which we should be learning from.

The conference closed with a panel discussion on the future of applied mineralogy. It is rather concerning to note that there was no real industry representation on the panel and begs the question of how “applied mineralogy” can be “applied” when the connections and relationships to industry are somewhat tentative. Unfortunately, this was one of the overall characteristics of this conference and although my general descriptions of the papers over the week have been positive, I do have to admit to focusing on those papers that are the most relevant to process mineralogy, and not the majority of the papers presented during the sessions. This is of course, really the niche which the MEI Process Mineralogy conference has, as evidenced by the many papers last year at Process Mineralogy '10 which were delivered by industry representatives. And so on that note, I am concluding my week of “blogging” for Barry by noting just how special MEI Process Mineralogy is relative to ICAM, and of course reminding you all not to miss out on Process Mineralogy '12 to be hosted 7-9 November in our sunny Mother City, Cape Town, South Africa.

Dr Megan Becker (Process Mineralogy ‘12 Conference Consultant)
Centre for Minerals Research
Department of Chemical Engineering
University of Cape Town
South Africa

Monday, 15 August 2011

New Comments Alert

There are new comments added to the following blog postings since the last comments alert:

What is the future for heap bioleaching?
Whatever happened to Axsia-Mozley?
Memories of the Nchanga Tailings Leach Plant
Flotation '11- can you afford not to be there?
Metplant '11 Conference Diary

We welcome your comments on blog postings. If you do not have a Google account, the simplest way to add a comment is by selecting 'anonymous' as your profile, but please leave your name and affiliation in the comment.

Sunday, 14 August 2011

Special Bio and Hydrometallurgy issue of Minerals Engineering published

Bio and Hydrometallurgy ’10 was held in Cape Town, South Africa in November last year. Nineteen selected papers from the conference have now been published in Volume 24 Issue 11 of Minerals Engineering, with a Foreword by the MEI Consultant Prof. Sue Harrison. The papers are also available electronically on ScienceDirect.

The Proceedings of the conference, containing unrefereed papers, is available from MEI.

Biohydrometallurgy ’12 will be held in Falmouth, UK, in June next year.

Saturday, 13 August 2011

A CSM reunion in Penryn

Despite being a little jet-lagged after my return from Perth, Barbara and I attended a very enjoyable and interesting Camborne School of Mines reunion yesterday at the Tremough Campus in Penryn, a short drive from Falmouth.

Our annual CSM reunions are organised by ex-CSM librarian Linda Shimmield, who now lives in Adelaide, but regularly comes over to her beloved Cornwall to visit friends and family.

We toured the very impressive CSM facilities at Tremough, part of the University of Exeter, and I was particularly impressed by the SEM facilities, including a modern QEM-SCAN, used mainly for research and teaching, producing students eminently trained in modern process mineralogy.

Gavyn Rollinson (2nd left) explains
the SEM services
We were shown around this section by Dr. Gavyn Rollinson,  whose enthusiasm for his subject had impressed me when we first met in Brisbane 3 years ago at Automated Mineralogy '08. These impressive SEM facilities are the results of the endeavours of ex-CSM Director Prof. Keith Atkinson, and Dr. Alan Butcher, former geology lecturer at CSM, who emigrated to Australia to work with QEM-SEM at CSIRO, then on to Intellection, who marketed QEM-SEM and QEM-SCAN, in strong competion with the JKTech's Mineral Analyser (MLA). After the demise of Intellection, Alan moved to FEI, and is now ironically involved with marketing both QEM-SCAN and MLA. He regularly visits Cornwall to advise on QEM-SCAN operation.

It was a great reunion, and I also thank Andy Wetherelt, head of mining engineering at CSM for arranging the tour.

Friday, 12 August 2011

Metplant '11 Conference Diary

MetPlant 2011, the 7th in the series of metallurgical plant design and operating strategies conferences organised by the AusIMM, was held at the Pan Pacific Hotel, in Perth, Western Australia, from 8-9 August 2011.

MEI was the conference media sponsor, and this is my diary of events, which I hope will be supplemented by comments from those who attended.

Monday 8th August
David Pollard
Metplant convenor David Pollard, Director of Salamander Consulting Pty Ltd, welcomed the record number of 330 delegates this morning, after which the conference was officially opened by Michael Catchpole, Chief Executive of the AusIMM. Although 13 countries are represented, 90% are from Australia. South Africa, Canada and Indonesia, the next highest represented, accounted for a mere 1.5% each. There is a good mix, however, of operators, academics and manufacturers, so it looks like being an interesting two days.

MEI is one of the 31 exhibitors at the event, and I look forward to meeting people at the exhibition, held in the coffee and lunch break-out area.

Chris, Joanne and Rachel of RJ Flotation
My neighbouring booth is occupied by RJ Flotation, an interesting consultancy team run by two dynamic young ladies, Rachel Morgan-Jones and Joanne Blair, pictured left with Joanne's brother Chris. Between them Rachel and Joanne have 25 years experience of delivering flotation services to the global mining industry. They operate from a commercial mineral processing laboratory in Perth and specialise in bench scale flotation testing using the latest Essa equipment.

Richard (Ted) Bearman called in at the booth during the short coffee break. He had just presented a paper on crushers, and their importance in comminution circuits, which declined with the introduction and resultant dominance of AG and SAG based circuits. The recent move to consider more energy efficient circuits has, however, caused the industry to reconsider the role of crushers.

Ted was a student of mine at Camborne School of Mines in the 80s. He is now Director of Bear Rock Solutions, his own consultancy company in Perth, and will be a keynote speaker at Comminution '12 in Cape Town.

Stuart Glen, Mike Battersby and Mike Adams
Mike Battersby, of Maelgwyn Mineral Services, UK is one of the two UK representatives at the conference. This week he is supporting Maelgwyn Australia, of whom Stuart Glen is General Manager and Mike Adams, of Mutis Liber, is consultant metallurgist. Mike Adams is also MEI consultant to Precious Metals '12. MMS is making advances in the Australasian market and is engaged in full campaigns of work with major mining companies, through laboratory and off-site then on-site pilot plant work, to demonstrate the potential of processes such as Leachox gold technology and the CN-D cyanide destruction process. Maelgwyn Australia is presently moving into vastly expanded premises in Welshpool, Perth, where they will locate the 2-stage Imhoflot G-Cell pilot plant. Results from work on this will be presented in 3 months time at Flotation '11.

Paul Toor of Scanalyse presented a paper after the coffee break on the influence of liner wear on milling efficiency. Over-design of liners leads to increased life but at a cost to grinding performance, a relationship which to date has not been studied closely. The paper showed how liner life cycle can be optimised using the Scanalyse MillMapper software. Data from surveys were modelled in JKSimMet to provide direct comparisons of mill performance. This potentially provides a methodology for the design of liners that maintain a favourable shape for the majority of liner life, yielding desirable production parameters such as lower specific energy consumption and higher throughput, while at the same time maintaining practical liner life cycles.

Paul Toor (centre) is pictured with Scanalyse chief technical officer Jochen Franke and business development manager Steve Chaffer.

Daniel, Francois, Karen and Pieter
Blue Cube Systems of South Africa is a Gold Sponsor of Metplant, and is represented by Francois du Plessis and Karen Keet. They are photographed at the Blue Cube/Mintek booth with Pieter Strobus, who represents Blue Cube and Mintek in Australia, and Daniel van der Spuy of Mintek. Blue Cube and Mintek have an alliance for grade measurement, control and optimisation, the product of this being the inline grade analyser (MQI) and Floatstar software for flotation control and optimisation. They will be presenting a paper at Flotation '11 on the separate measurement of copper oxides and sulphides for flotation control, a world first. Francois is also planning a guided walk on Table Mountain for those interested. Details will be posted on the latest news updates when available.

I talked to Brian Packer and Simon Abrams of Western Process Equipment, who are representatives of Derrick Corporation, well known for fine screening. Brian had just presented a paper on the benefits that high frequency screens offer over hydrocyclones in closed circuit grinding. Western Process Equipment also represent Eriez Magnetics and sepro mineral systems, the latter being purchased by Falcon Concentrators in 2008. They manufacture scrubbers, small rod and ball mills, and agglomeration drums, as well as the Falcon Concentrator. The new Falcon ultrafine (UF) model operates at up to 600G, and is being used to treat scheelite, tin and tantalum at low capacities down to sizes as low as 3 microns.

For gravity concentration at coarser sizes, the Gekko InLine jig has found favour for separation of material with less than 0.5 SG differential at sizes larger than 300 microns, the aim, as explained by technical director Sandy Lewis-Grey (pictured with sales manager Tim Bell (right) and Phil Reese (centre) of Manas Resources) being to efficiently increase effective liberation sizes. They are currently being used for separations in silver, tin and zinc operations, as well as for gold sulphides. Gekko Systems are sponsors of the gravity concentration section of MEI Online, but they are also actively involved with modular processing plants. The 'Python' units are increasingly being used in small gold operations and are currently in operation with Goldfields in South Africa, as well as in Vietnam and Mexico.

Diana Drinkwater, the metallurgy training manager with the JKTech presented a paper this afternoon on how professional development can improve the technical skills of metallurgists. The work schedules of today's metallurgists have a very different balance between technical and non-technical responsibility than those in the past, and she showed how a shift towards a more technical focus has potential to deliver a range of benefits for industry at large and for the individuals in it.

Diana organises the JKTech's programme of professional development courses and workshops, three of which are scheduled to run in conjunction with November's Flotation '11.

The JKTech and North America's InfoMine have formed a joint venture company called R2Mining, which is currently in the process of extending the CostMine products into Australia and Asia. Since 1983 CostMine (previously Western Mine Engineering) has been providing the most comprehensive data for mine cost estimation and cost modelling for mining and mineral exploration in North America. R2Mining's general manager, Sean Shafiee is pictured with Diana Drinkwater and the JKTech's group metallurgist Sarah Schwarz.

Tonight's conference dinner was held in the ballroom of the Pan Pacific Hotel. It was a very pleasant evening which gave delegates and their partners the opportunity to socialise in a very relaxed atmosphere. I enjoyed meeting undergraduate metallurgists from Murdoch University, who had been given the opportunity of networking at the conference and dinner in return for their assistance with the conference infrastructure. It was also great to share a table with Ted and Clare Bearman, both ex-students of mine at Camborne.

Conference delegates and partners at the dinner predrinks

With Murdoch University students

Tuesday 9th August
I had a pleasant chat this morning with a couple of the Murdoch University students who I had met last night. They were unaware of MEI Online and its comprehensive job vacancies section, and the fact that there are free subscriptions to the fortnightly newsletters of news updates and job vacancies. Although the job vacancy section is international, they were surprised to see that the majority of mineral processing vacancies are within Australia.

Another welcome visitor to the MEI booth was Dan Curry, who I had lost touch with since his Xstrata Technology days. I last saw him in 2006 at the Ultrafine Grinding conference in Falmouth. Dan is now development leader for metals and mineral processing with Aurecon, based in Perth. Traditionally Aurecon has been involved with the design of infrastructure, and Dan's current role is to develop the company's mineral processing business, particularly the design and development of plants.

AMEC Minproc delegates
Geometallurgy is attracting increasing attention and is the subject of the AusIMM's conference GeoMet '11 in September, and one of the themes in next year's Process Mineralogy '12. Greg Harbort of AMEC Minproc Ltd, presented a paper this morning on the integration of geometallurgy with plant design. The use of geological data for optimisation of operating plants has become a significant part of the modern process mindset. At a design stage the process designer can use geometallurgical information to evaluate bottlenecks and potential design flaws and propose the best investment strategies for the project benefit.

Greg is a co-author of the book History of Flotation, and is pictured with AMEC colleagues Sarah Ball, Dave Morris and Todd Back.

Outotec is the principal sponsor of Metplant, and has a strong presence at the conference. Process equipment manager Rob Coleman presented a paper this afternoon showing how the flotation mechanism plays a key role in the flotation process. It is used to provide the contact between solid particles and bubbles and also the energy for these particles and bubbles to attach. The mechanism must therefore provide sufficient mixing to keep the solids in suspension so that they can be transported into the froth and recovered to the concentrate. The design of the mechanism is critical and over the past decade Outotec has developed and optimised a new mechanism designed to improve metallurgical and energy performance. The FloatForce mechanism consists of a rotor and stator arrangement and has been specifically designed to provide sustained mixing at higher air flows and lower power inputs. Over 500 of the mechanisms have been installed in existing and new operations. The Outotec team are photographed with the FloatForce unit, left to right John Durie, Laura White, Chris Greenwood, Steve Casas, Krystle Lusk and Rob Coleman.

The FLSmidth booth
Following afternoon tea, Jeff Euston, flotation product manager at FLSmidth presented a paper reviewing the science which supports, and occasionally challenges, the ongoing trend to larger flotation cells. In the last 20 years flotation cell sizes have increased almost exponentially and designs of 250 to 300 m3 are well established standard with plans for full scale pilot installations of 500m3. The benefits of scale up are well known, with reduced numbers of cells required, lower power costs per unit volume, etc., but the sophisticated techniques required to model these 'supercells' have led to a critical review of the fundamentals of flotation science and engineering.

FLSmidth is a gold sponsor of Metplant, and regularly sponsors MEI Conferences. Jeff Euston is pictured (right) in the FLSmidth booth with sales engineer Amit Zadoo and global product manager Paul McCurdie.

I have enjoyed the two days at this conference, catching up with old friends and meeting interesting new people. I particularly enjoyed talking to the Murdoch University students, and wish them every success in their careers. I hope they realise how fortunate they are to be involved in this crucially important industry, where technology must continue to evolve to deal with increasingly complex feed materials.

The Proceedings of Metplant 2011 are available on CD, price A$55. Details are at Metplant 2013 will also be held in Perth. Details will be on the MEI Conference Calendar as soon as dates are known.

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Wednesday, 10 August 2011

Innovations in Flotation Machine Design

Following the closing of Metplant '11, I attended an excellent lecture yesterday evening given by Prof. Michael Nelson, department chair in mining engineering at the University of Utah, USA.

This was the inaugural lecture in what will become a series of G.D. Delprat Memorial Flotation Lectures, instigated by Prof. Alban Lynch, the first Director of Australia's JKMRC.

Profs. Nelson and Lynch are co-authors of the AusIMM book The History of Flotation, along with Dr. Greg Harbort of AMEC Minpro. The royalties from the book partially funded the lecture, which was also sponsored by FLSmidth and Outotec.

Although entitled 'Innovations in Flotation', Prof. Nelson focused on mechanical flotation cells, and the trend to ever larger machines. This caused some concern with some members of the large audience, who were expecting opinions on column and Jameson Cells, and a representative from CSIRO questioned whether this focus on mechanical cell size, an area driven by operators and equipment manufacturers, undermined the huge role that research institutions and academia have played in the development of reagents and our understanding of the science of flotation.

Accepting this, and explaining that a short lecture such as this must concentrate on a specific area, Michael presented a fascinating history of how cells have developed since their first use on zinc tailings at Broken Hill in 1905, pioneered by G.D. Delprat, one of the most unrecognised, yet important figures in flotation.

The first Minerals Separation cells were pneumatic, and prone to blinding, and were later superceded by Denver Sub-A, Wemco Fagergren and Galigher Agitair cells, the Denver Equipment Company dominating the market by the middle of the century, with over 50% of world sales. A feature of flotation plants in those days was a multitude of parallel banks of many small cells in series, something I remember from my days at Nchanga in the early 70s where many rows of tiny 1.2 m3 Denver Sub-A cells, 20 in series, were gradually being replaced by the then massive 8.6 m3 Fagergrens.

The quantum change in cell design was the move to very large cells, with the development of large cylindrical cells by Outokumpu in the early 80s, with corresponding reductions in overall capital and operating costs, as well as ease of control. With developments in rotor and stator design, cells of up to 300 m3 are now standard, with plans for 500 m3 cells at full pilot scale.

In concluding Prof. Nelson mused on where the next innovations might be made and suggested that we should be looking outside the narrow confines of the minerals industry, and evaluate the methodologies used in related fields, such as dissolved air flotation in water treatment, and techniques used in oil and tar sands processing, as well as the new field of nanotechnology.

Overall I found this a very interesting and informative lecture, which was very well presented. Prof. Nelson has presented this before in various cities, so if it comes to an area near you, I would definitely advise that you make the effort to attend.

Monday, 8 August 2011

Metplant '11 off to a good start

I am in Perth this week for the 2-day Metplant 2012, organised by the AusIMM.

I arrived just after midnight on Saturday morning, and had a leisurely weekend, including a pleasant pub lunch yesterday with the Maelgwyn Mineral Services team.

It is only 2 months ago since my last visit, but prices here have continued to rise to crazy heights. On Saturday night I ate at an Indian Restaurant, but was staggered by the bill of AUD57 (£38) for a curry and a small beer, roughly twice what I would expect to pay in UK.

But enough of the whinging pom. Metplant got off to a fine start this morning, with a high turnout. MEI is the media sponsor, and my conference diary will be published on the blog at the end of the week.