Monday, 28 September 2015

See who is coming to Flotation '15

Things are looking good for Flotation '15 in 7 weeks' time.

We have just published the delegate list as it stands today, and will be updating this every Monday up to the conference.

Join us in Cape Town in November.
Registration details
Provisional Programme

Many thanks to our sponsors:

Saturday, 26 September 2015

SAG '15 Conference Diary

By any standards the Semi-Autogenous and High Pressure Grinding Technology (SAG) conferences are very important events on the comminution calendar. Essentially operators' conferences, this was the 6th in the series, which was initiated in 1989, and has always been held in Vancouver, the previous one in 2011. This year's event was held over four days, from September 20-23 at the Pinnacle Hotel Vancouver Harbourfront, and was organised by the SAG Conference Foundation, a Canadian registered non-profit organisation.  
Vancouver Harbourfront
The conference attracted over 650 delegates engaged in the field of autogenous, semi-autogenous and HPGR grinding in the industrial and metalliferous mineral industries to an intensive 4-days of over 100 oral presentations, supplemented by poster displays, and for the first time in the series a trade exhibition. Roughly 64% of the attendance was from North America, 11% from Australia, 5% each from Chile and South Africa, the remaining 20% being thinly distributed over 26 countries.
This was my first attendance at a SAG conference, MEI being a media partner, so I knew little of what to expect, approaching the four days with anticipation of making new contacts amongst the huge audience. I used the exhibition area as a focus for networking and this is my diary of a great week in Vancouver.
Sunday September 20th
The conference was opened this morning by Bern Klein of the University of British Columbia, and Chairman of the Local Organising Committee. 
Bern Klein with local organising committee members Laurie Reemeyer,
Mike McClintock and Reem Roufail
With Technical Chairman Brendan Costello, of Fluor Canada,
one of my CSM students from the 1980s
As comminution is the most energy intensive operation in mineral processing, it was appropriate that the first five papers before the first coffee break dealt with energy in comminution and that the first of these was presented by Grant Ballantyne of the University of Queensland, and a member of the Coalition for Eco-Efficient Comminution (CEEC). The CEEC, still a relatively young organisation, now has a very high profile in the industry, and MEI is proud to have its involvement in Comminution '16 as an industry advocate.
Grant discussed the CEEC's energy curve program, which is growing rapidly, with over 1.3 billion tonnes of ore in the database already. This program shows each operation where it currently sits on the efficiency curve, similar to a cost curve. Not only does it show where an operation sits on the curve, it also shows the position relative to other mining operations, so that improvements in processing efficiency can be tracked using this tool. CEEC's program is offered free to the industry: operating data is analysed into the program; the individual detailed results are sent in confidence back to the participant, while the unidentified data is added to the collated global data.
CEEC is running workshops around the world to demonstrate the application of the CEEC energy curve. Details to sign up for the CEEC workshop prior to Comminution '16 are already on CEEC's web site and plans are in place for similar events in Perth, Brisbane, Santiago and Turkey over the next 12 months. Last month FLSmidth added its global strength to CEEC’s mission to accelerate the transfer of knowledge around more efficient and productive mineral processing strategies (MEIOnline).
CEEC Executive Officer Sarah Boucaut, board members Ivan Mullany and Zeljka Pokrajcic,
and Grant Ballantyne with FLSmidth Sr. Vice President-Executive Accounts Peter Flanagan
With Rob McIvor
In the same session as Grant's paper, Rob McIvor of Metcom Technologies, USA described and gave examples of grinding circuit efficiency measurements and systematic application for the improvement of grinding circuits. Rob will be presenting a keynote along these lines at Comminution '16 aimed squarely at operating metallurgists and company management, as well as a pre-conference workshop to assist plant metallurgical staff and equipment/material suppliers to manage and improve the processing performance of ball milling circuits with clarity and confidence (posting of 1st June).
Following Rob's presentation were a further 20 presentations, in sessions on energy, geometallurgy, pre-concentration, and testwork and ore characterisation for SAG and HPGR. A very full day from 8 am to 6.30 pm with short breaks for coffee and lunch. A nice feature, however, was the streaming of the presentations into the exhibition area, which facilitated dipping into and out of sessions.
Steve Morrell presented the first Geometallurgy paper, on global trends in ore hardness. Steve is founder of CITIC SMCC Process Technology Pty Ltd an Australian company which provides independent technical services to various mining projects, mainly in the area of comminution circuit design, technology and equipment selection, and optimisation of mineral processing plants. It operates as an independent consulting company, and is ultimately owned by Comminution '16 sponsor CITIC Heavy Industries, a market leader in China, with equipment operating successfully in China and around the world, including Asia, Europe, America, Africa and Australia.
Steve is 2nd left in the photo below, with Rajiv Kalra, managing director of CITIC Australia, Beny See Hoy, general manager North America and Mexico, and Dave Lumsden, global manager- crushing. On display was their stirred mill, three of which are currently being installed in Chile by Codelco.
Geometallurgy is becoming increasingly important in the minerals industry and Marcos Bueno of Australia's Ausenco stressed its importance in comminution testwork programmes, to characterise the ore in order to describe the variability of ore breakage properties. Geometallurgical approaches consider the mine sequencing and the characteristics of different ore types, thus minimising risk in comminution circuit design.
It's always good to meet husband and wife teams, and Henry and Susan Kurth, of Australian company Scantech, were no exception. Susan is Marketing Administrator and Henry Vice President-Sales for North America, and this afternoon he presented a paper on the Geoscan Elemental Analyser for optimising plant feed quality and process performance. Geoscan is used for multi-element analysis of conveyed bulk materials in real time, weighted tonnage results being used to monitor quality, divert increments (bulk sorting), ore blending and feed forward control to optimise downstream processes.
Monday September 21st
A nice feature of the conference is delegates' breakfast, a full hot and cold buffet served each morning from 6.30 in the conference area, where I have been able to catch up with a few familiar faces.
Malcolm Powel and Luis Tavares
Two of these were Profs. Malcolm Powell, of Australia's JKMRC, and Luis Marcelo Tavares of the University of Rio de Janeiro, Brazil, who presented papers on simulation this morning. Malcolm and Luis represent two of the six institutes comprising the Global Comminution Collaboration, which identifies comminution research needs and unifies the approach to working on these needs. The other four institutes are Sweden's Chalmers University, the University of Cape Town, Germany's Technische Universitat Braunschweig, and Turkey's Haceteppe University. At the recent AGM Luis stepped down as chairman, to be replaced for a one year stint by Prof. Arno Kwade of Braunschweig.
If yesterday was intensive then today certainly was, presentations commencing at 8am and finishing at 8.20pm, with two 20 minute coffee breaks and two one hour breaks for lunch and afternoon reception and buffet.
Nine posters were also displayed today in the exhibition area. Two of these were from Andritch Automation, who provide automation solutions, including controls, electrical and power engineering. The two poster presentations, the first entitled “Calculating SAG mill bearing pressure using thin film hydrodynamics” and the second “SAG-mill-optimization-using-model-predictive-control” emphasise the importance of modelling and advanced control in SAG mills. The long term vision is to enable the industry to more effectively use the equipment they have purchased through optimal circuit design and control. Andritch simulation tools help design or debottleneck mineral processing plants, and the company has donated its IDEAS simulator to mining Universities around the world, and at UBC the 40 license donation is being used at the undergraduate level to help students understand process unit operations when in steady state mode and also as a tool to introduce students to process control when in dynamic mode.
The Andritch team with UBC's Reem Roufail (3rd right) and Stefan Nadolski (2nd right)
The morning technical sessions contained presentations on Discrete Element Modelling, and Modelling and Simulation. After lunch there were sessions on Circuit Design and Mill Drives.
Metso has a high profile at most important conferences, and Victoria Herman, product manager for Metso's HRC High Pressure Grinding Rolls, gave a presentation this afternoon on the building of the world 's largest HPGR, the HRC3000, at the Morenci Metcalf Concentrator, part of the 63,500 tpd expansion at the Freeport-McMoran site. Victoria is photographed below with others in the Metso team.
Australian company Bradken is a leading supplier of high quality mill liner systems to suit AG/SAG, ball and rod mills, and in the evening session on Mill Liners, Product Technology Manager Craig Faulkner described a step change in liner design for the 32ft SAG mill at Kansanshi in Zambia.
Craig Faulkner, 3rd left, with other members of the Bradken team
Polycorp is one of the leading rubber liner manufacturers in North America, and the company's PolyStl™ liners are the composite of a special wear resistant steel and high pressure moulded rubber. Similar liner designs have been used for many years in AG / SAG mills up to 32 feet in diameter. Pictured below are the Polycorp team. Pramad Kumar (3rd left) co-authored a paper this evening on PolyStl™ liner development at Chirano Gold Mines in Ghana, which was presented by University of Utah's Raj Rajamani.
In the next booth was Tega, another company supplying liners for primary grinding, autogenous and semi-autogenous mills, and in the photo below representatives were discussing their products with some of the strong delegation from China.
The Chinese delegation

Tuesday September 22nd
Another intensive day of presentations from 8am to 8.20 pm, supplemented by 10 new poster displays. Today's sessions covered fine grinding, AG/SAG circuits, HPGR circuits start-up, SAG pre-crushing, process control, and operating practices.
Outotec has a presence at all major conferences, having just committed to sponsoring the next 4 MEI Conferences (posting of September 24th). Hanspeter Erb is hoping to present a paper at Comminution '16, and this morning reviewed the metallurgical performance of the HIGmill™ in a primary milling application. The target was to verify whether the mill could handle coarse feed (3-5mm), ultimately aiming to provide a more energy efficient alternative to ball milling. He is pictured 2nd left with other members of the Outotec team, including Steve Schmidt (left) who I have not seen for a few years. Steve was a regular with Xstrata Technology at MEI's comminution conferences. After 13 years with Xstrata, he moved to Outotec this year as commercial product manager focusing on fine grinding.
Interestingly Hanspeter's paper immediately followed Chris Rule's presentation. Chris, of Anglo American Platinum, showed how ISAMill™ technology has progressed from the original Mount Isa Mines ultrafine grinding applications. Larger ceramic media is now pushing the boundaries of feed size and can offer advantages in grinding efficiencies, product size distribution and internal wear. It is evident that stirred mills are going to play a big part in future circuits, and that there will be an inevitable decline in the use of ball mills.
During the first coffee break I looked in at the poster displays, and caught up with 8 of the 9 delegates from the University of Cape Town.
Also good to see one of my CSM students, Paul Morgan, by his poster on the introduction of Turbo Pulp Lifter System at Karowe Diamond Mine in Botswana. Paul graduated from CSM in 1986 and is now Consultant Engineer-Comminution with South African company DRA, although he works from home in Scotland.
With DRA Director Glenn Bezuidenhout and Paul Morgan
Starkey & Associates Inc. is the name behind a number of the most successful SAG circuit designs in the mining industry today, their projects spanning the globe. Eleven well known testing laboratories work with the company to provide SAGDesign™ testing services and I recently reported on the installation of a test mill in Cornwall, UK. So it was good to catch up with John Starkey, a regular sponsor of MEI's comminution conferences, who invented the SAGDesign™ test, now acknowledged to be a world-class method for grinding circuit design, and is accepted as a standard for ore hardness testing. Starkey & Associates uses the patented SAGDesign™ technology to calculate accurate mill sizes from measurements on a client’s own ore samples, and one of these clients is Russian company TOMS, also a regular MEI comminution conference sponsor. In this morning's session John discussed new projects in Russia for hard and soft ores with SAG mills selected from the results of SAGDesign testing.
John Starkey (2nd right) at the TOMS booth, with interpreter Ekaterina Butko,
Head of Crushing and Comminution Yury Kulikov, General Dorector Arkady Senchenko
and Contract Manager Anna Dergacheva
German company Koppern is a specialist in engineering, manufacturing and technical services for roll presses and HPGRs worldwide. In this afternoon's session Andrew Gardula, Managing Director of Koppern Australia described the first year of operations of a HPGR at the Tropicana Gold mine, in Western Australia. He is pictured right with Managing Director Christopher Schafer and Senior Process Engineer Felix Heinicke. Felix also presented a paper, on Sunday evening, on mathematical-petrographic rock characterisation as support for sizing of HPGRs.

Wednesday September 23rd
The last day got off to an interesting start with a presentation by Paul Staples of Ausenco, Australia, who asked whether SAG mills are losing market confidence. Although a mature technology, a number of recent projects are not achieving nameplate capacity, and he gave a critical review of underperforming AG/SAG mills based on public domain information comparing design expectations with actual operational performance.
With Dave Meadows
The whole morning was devoted to SAG/AG circuit optimisation, and Dave Meadows of Bechtel, USA added to Paul's theme by reviewing the grinding circuit design and performance at Antofagasta Minerals Centinela concentrator in Chile, which was commissioned in 2010. At that time the grinding circuit featured the largest of a kind SAG mill at 12.2m x 7.92m and two 8.2m x 13.6m ball mills. The plant met the nameplate capacity in late 2011 but had some challenges in upstream and downstream plant areas.

It was good to see Dave at the conference, another of my mid-1980s CSM students. For a long time he was with FLSmidth, but recently moved to Bechtel as global manager of metallurgy.
Following the lunch break there were sessions on HPGR optimisation, and General Interest. One of these papers, the 3rd from the end, should provide a useful reference for applied SAG mill operation in the industry. Malcolm Powell of the JKMRC, Australia presented a compilation of common operational issues encountered on SAG mill circuits worldwide. Twenty issues were listed, the symptoms described, and some theoretical background provided upon which the routes to tackle these issues are based.
The penultimate paper was presented by Ricardo Fernandez, of Weir Minerals, Chile. He described how AG or SAG milling frequently becomes a bottleneck in an operation as the generation of critical size pebbles, and the subsequent required re-crushing of these, results in an extra burden for the (S)AG mill in the form of a recirculating load of harder and more abrasive material. HPGR crushing may provide a profitable alternative or addition, allowing the crushed pebbles to be bled to the subsequent downstream ball mill and beneficiation stages, thus freeing desired capacity for the (S)AG mill stage and enhancing overall plant throughput.
In the photo below Ricardo (3rd left) and other members of the Weir team are showing me models, all produced by 3D printing, of their range of crushers.

Before conference Chairman Bern Klein wound up a memorable conference in the late afternoon, McGill University's Jim Finch invited everyone to attend next year's IMPC in Quebec City, with a reminder that the deadline for abstracts is the end of this month - over 700 have already been submitted!

Personally I found SAG '15 to be a very rewarding event and despite the very short breaks between sessions I managed to make a lot of new contacts and catch up with many familiar ones, many being pleasant surprises as no delegate list was available.
With so many papers presented, I could only scratch the surface of the technical content in this report, so I invite those who attended to add their own comments on their own particular highlights and thoughts. And how was the Conference Dinner on the final night, which unfortunately I had to miss?
In thanking the organising committe for a very well organised event, let's not forget the team of enthusiastic student volunteers from the University of British Columbia, who are pictured below with conference registrar Alex Doll.
Back row: Tugba Cebeci, Diana Nakuru, Alex Doll, Yiran Zhang, Hongtao Ma and Nawoong Yoon
Front row: Pei Li, Amit Kumar, Siddhant Kar and Sijia Liu
The conference Proceedings is available via the SAG '15 website, and the next event is provisionally planned to be held in 2019. MEI will certainly be there, and I hope to see many of the delegates from SAG '15 at next year's Comminution '16, which in many ways complements the SAG series.

Thursday, 24 September 2015

Minerals Engineering Conference 2015 report

by Tomasz Niedoba and Agnieszka Surowiak,
AGH University of Science and Technology in Krakow, Poland

On September 14-17, 2015, the Mineral Engineering Conference 2015 (MEC 2015) took place in Szczawnica, at the hotel “Nawigator”, Poland. Previously this cycle of conferences was held as joined conferences: XX International Conference of Mineral Processing and LII Symposium on Physicochemical Problems of Mineral Processing. This year’s main organizer was AGH University of Science and Technology in Krakow, Faculty of Mining and Geoengineering, Department of Environmental Engineering and Mineral Processing.

76 delegates attended the MEC 2015

The Conference started on September 14 with a Plenary Session which took place in Dworek Gościnny – one of the most beautiful buildings in the city of Szczawnica which is one of the most known Polish spas. During this session, two jubilees took place because of the 70th Anniversaries of Professor Andrzej Łuszczkiewicz from Wroclaw University of Science and Technology as well Professor Aleksander Lutyński from Silesian University of Science and Technology. After short laudations the jubilates gave very interesting speeches about current trends, opportunities and threats in mining.

In the evening, a grill party took place which was organized in horse stud “Rajd”, located in Jaworki, about 8 km from Szczawnica. The delegates were transported there by buses.

The second day was dedicated to the main scientific part of the Conference. In two parallel sessions, divided into morning and afternoon sessions (Physicochemical Problems of Mineral Processing and Minerals Engineering ones) about 50 speeches were presented. The topics of the presentations were various, including the technological aspects of mineral processing, modern solutions, mathematical modeling and optimization, monitoring, reclamation or measurements in mining. All papers were prepared professionally and were very interesting.

In the evening, diner was organized in the Jazz Club, located next to Dworek Gościnny, where the plenary session took place.

The third day started with a special session of papers which were part of the other conference – the 3rd Polish Mining Congress, of which the main part took place in Wroclaw. The delegates of the Mineral Processing part of the Congress were invited to Szczawnica to present their speeches. All together, 15 presentations took place within this session. In the afternoon, the delegates had an opportunity to participate in one of the most famous attractions of Szczawnica – Dunajec river rafting. This is a 2 hours event during which tourists can enjoy the beauty of the Pieniny mountains while sitting in a raft. Fortunately, the weather was very good so it was possible to truly feel the atmosphere of these beautiful locations.

Rafting on the beautiful Dunajec river

In the evening, the Gala Dinner was organized again in Dworek Gościnny. During this event the official closing of the Conference took place. After it, the delegates could enjoy the evening which ended at 3 am next day.

On Thursday September 17, the delegates traveled home after breakfast.

All together, 76 delegates took part in the Conference. Apart from Polish delegates from universities and industrial plants, also the international guests from such countries as Finland, Great Britain, Nigeria, Iraq, China PR, Egypt, Turkey and USA were present. The general number of presented papers was 65. We invite everybody for next year’s edition of MEC, which will be organized by Wroclaw University of Science and Technology.

Further information about the Conference MEC 2015 can be found on the website  

Outotec weighs in with major support for Biohydromet '16

All is looking good for MEI's June conferences in Falmouth, where Biohydromet '16 and Sustainable Minerals '16 will run back to back.

We are very pleased to announce that giant international company Outotec, who agreed some time ago to support Sustainable Minerals '16 (posting of 13th April), is to provide corporate sponsorship for Biohydromet '16.

Outotec is relatively new to the biohydrometallurgy field, having recently acquired the majority of the shares in Biomin South Africa Pty Ltd and certain assets from Biomin Technologies S.A. in Switzerland (MEI Online). Biomin's BIOX® technology, a proven technology for bioleaching, complements Outotec's portfolio of gold processing technologies.

We are proud to continue our long association with Outotec, who is also sponsoring Flotation '15 and Comminution '16 in Cape Town prior to the June conferences in Falmouth.

Monday, 21 September 2015

Vancouver's Bayshore

After two days confined to the hotel, I managed to escape for a couple of hours this afternoon and walked down to Gas Town and then back along the Bayshore

Although the city has developed since my last time here, 23 years ago for Minerals Engineering '92, the Bayshore has changed little, and the two photos below were taken a few minutes walk from the conference hotel, The Pinnacle.

Sunday, 20 September 2015

SAG '15 off to a good start

I am in Vancouver this week for the 6th Semi-Autogenous and High Pressure Grinding Technology conference.

This is without doubt the most important operators' conference for comminution technology, and always attracts a huge audience, this year well over 650. It is very intense, this week over 100 papers will be presented in oral sessions over the four days, and these will be supplemented with poster presentations, and for the first time, a trade exhibition.

MEI is the official media partner, and I will be publishing a report on the conference early next week.

Thursday, 17 September 2015

Official Opening of the Drakelands Tungsten-Tin Mine

Fourteen months ago I called in at the Wolf Minerals' Drakelands Mine at Hemerdon, near Plymouth, (posting of 10th July 2014) to see how things were progressing on the building of the processing plant with its interesting flowsheet (posting of 25th June). The site was certainly a hive of activity and commissioning took place ahead of schedule, at the end of June.

The processing plant site in June 2014
Speaking at the last CSM Annual Dinner (posting of 15th March) Wolf Minerals Managing Director Russell Clark said that there had been little local opposition to the mine. “People think that as you’re on Dartmoor, there must be protests. I have never seen support like this. We’re lucky we are in an area that has a mining history. A lot of local people are used to seeing a pit, used to seeing a quarry, and they recognise it’s good for the economy.” 

Production of tungsten is dominated by China, which has about 60 per cent of global reserves, but Drakelands could be the biggest tungsten mine in the Western World. However, since my last visit the price of tungsten, like most metals, has fallen markedly and Russell recently said that if prices were going to stay where they are now for the next 20 years the mine probably would not have been built, but he doesn't believe they will. In a recent interview in The Times (September 2nd 2015) he insisted that the market was at its lowest ebb. "There's going to be a point where people need to go back to the global market. At that point there will be a spike in the tungsten price and we should be in the perfect position to deal with it" he said. There are already signs that the weak market is forcing high-cost operators to shut down, and some private Chinese producers are beginning to close their operations.

No matter what happens, today was a very significant date in the mine's history, and I was privileged to be invited to the mine's official opening ceremony. Prior to that I joined the tour of the processing plant organised for media and brokers, and I was very impressed by how things have progressed since my last visit 14 months ago, the plant now producing 20 tonnes per week of tungsten concentrate.

Due to the high density of wolframite and the by-product cassiterite, gravity concentration dominates the flowsheet, DMS cyclones, spirals and shaking tables producing a combined W-Sn concentrate, from which arsenopyrite is removed by froth flotation.

Crucial to the flowsheet is a kiln which roasts hematite to magnetite, which is removed by low-intensity magnetic separators, before high-intensity magnetic separation separates the tungsten concentrate from the tin concentrate, the latter providing about 10% of revenue.

The DMS cyclone plant
DMS Cyclones
Tables and spirals
Shaking table

Monday, 14 September 2015

Comminution Handbook Launched at MetPlant '15

The Comminution Handbook (posting of 24th August) will be a welcome addition to the bookshelves of many practicing metallurgists and process engineers, as it has been many years since there has been a new publication of kind. Its sixteen chapters are structured around the themes of breakage characterisation, processing equipment, circuit design and process optimisation and control.

Edited by Prof. Alban Lynch, with contributions from 38 world experts, the book was launched last Monday in Perth, on the first day of MetPlant '15 organised by the AusIMM (see MEI Online for report on the conference). MEI was a media partner for the conference and I wish I could have attended to meet members of the Lynch family who were there to launch the book. Due to a recent fall, Alban could not be there in person, but his son Martin, daughter Suzy and grandson Clem were, together with his daughter-in-law Elizabeth (married to son Patrick, who was away.

Also in the photo below, kindly supplied by Suzy, are Janine Herzig, who officially launched the book on behalf of the AusIMM, and Greg Lane, a valuable contributor to the book, from Ausenco.

Clem Lynch, Martin Lynch, Janine Herzig, Greg Lane, Suzy Lynch-Watson and Elizabeth Lynch
I believe the book is set to become a seminal volume, and the MetPlant conference delegates clearly agreed, all 56 copies brought to Perth by the AusIMM staff being sold on the spot, with back-orders taken for many more. 

Thursday, 10 September 2015

Zeiss Mineralogic Mining comes to Cornwall

Last week I reported on my visit to the impressive SGS Minerals Services laboratories at Wheal Jane, near Truro. Their mineralogical support is provided by Petrolab in nearby Redruth, whose local clients also include Wardell Armstrong International and Grinding Solutions, as well as Wolf Minerals' new Drakelands mine in Devon.

I called in at Petrolab last week to look at the installation of their new Mineralogic Mining automated mineralogy system (MEI Online), being installed by Al Cropp and Ben Tordoff of Zeiss. Both Zeiss and Petrolab are major sponsors of MEI's Process Mineralogy '17 and Zeiss is providing the same corporate support for Flotation '15 and Comminution '16, highlighting the company's current high profile in terms of innovation and industry presence.

Zeiss has worked very hard to make the Mineralogic platform versatile and robust in terms of method of analysis, automation and reproducibility. This versatility means that Petrolab can provide the latest innovative solutions and support for their metallurgical test programs. Petrolab Director James Strongman told me that, looking forward, he wants to see automated mineralogy become an integral part of all aspects of the mine from exploration and feasibility to environmental impact and remediation, and in collaboration with the application team at Zeiss he is very excited about the opportunities ahead.

Petrolab is actively involved and very keen on collaboration with academic research, and is currently supporting PhD research at the University of Plymouth into REE mineralisation and a recently completed MSc with Camborne School of Mines looking at the gravity and magnetic response of some rougher table feed samples supplied by Wolf Minerals. The MSc was very successful and James is now looking to take the student Jake Harrison on full-time as a junior mineralogist and lab assistant.

The link with CSM is an important one, and not surprising as Petrolab was founded in 1991 by Dr. Alan Bromley, who I worked with for many years at CSM. He was an inspirational geologist with a real interest in mineral processing, and a lecture that he gave way back in 1975 "A geologist looks at mineral processing" had a profound influence on the way that I also looked at mineral processing, as he showed that mineral processors should have a thorough knowledge of the mineralogical composition of their ores and concentrates. Now this is obvious, but at the time I had left Zambia only a couple of years before and during my time on the Nchanga Concentrator it is hard to believe now that, despite the wide suite of copper minerals, there was not even an optical microscope in the metallurgical office. If the tailings assay was creeping up, the answer was to add a little more reagent to the head of flotation, with little thought that the high assay may have been due to poor grinding, or the presence of poorly floating minerals.

It was great to see Alan at Petrolab. He sold the business to James in 2006, and John Fletcher joined James as co-Director in 2007. Alan had nothing but the highest praise for what they have done over the past decade, their impressive staff now comprising the two directors, two mineralogists, one software engineer and a thin section technician.

At Petrolab with Ben Tordoff, John Fletcher, Alan Bromley, Al Cropp and James Strongman
It is really good to see all the collaboration that is taking place now in the very dynamic minerals sector in Cornwall, and expect to hear much more of Petrolab and others in the future.

Tuesday, 8 September 2015

European Symposium on Comminution and Classification

Today is the first day of the ESCC2015 Conference, held in Gothenburg, Sweden. MEI is the official media partner, but as I was unable to attend I am grateful for this short report sent by the Local Organising Committee:

Professor Magnus Evertsson from Chalmers University of Technology began the conference by talking about that the long term sustainability and energy use is a unifying theme for the ESCC 2015 symposium. During the last century humankind has transformed from being a small world on a large planet to being a large world on a small planet. The debate around global warming and climate change is intensified. We do need to find sustainable solutions that are truly long term. A fossil free world is claimed by some researchers to be within reach in 35 years. To achieve that goal or at least to work in that direction, researchers in academia and industry have to join forces and we all need to contribute and cooperate to find smarter, cooler and more technically advanced solutions to our needs.

The first keynote speaker of the day was Professor Luis Marcello Tavares (Universidade Federal Rio de Janeiro) with his presentation about Advanced Modeling of Ball Mills, followed by Greta Fragnière (TU Braunschweig) and her presentation about Evaluation of a Mechanistic Model for Prediction of Breakage Rates Through Simplified Test Material and Malcolm Powell (University of Queensland) who talked about The Effect of Loading Rate in Single Impact Particle Breakage using High Velocity Breakage Device.

Todays sessions will cover the themes:
* Comminution and classification of industrial minerals, cement, ores and secondary materials.
* Grinding, dispersion and classification of fine particles
* Fundamentals, modelling and simulation

This seems to be the season for comminution conferences. MEI was also a media partner for last month's International Comminution & Classification Congress in Mexico, but my attempts to get there were thwarted by problems with my BA flights. In just over a week's time I will be in Vancouver to report on SAG '15. And then, of course, the end of next month is the deadline for abstracts for MEI's Comminution '16 in Cape Town.

Monday, 7 September 2015

Comminution '16 Final Call for Abstracts

With mining companies having to tighten their belts in these hard times, the importance of optimising comminution, the most energy intensive operation in mineral processing, becomes ever more important.

Comminution '16, which will be held in Cape Town in April is the 10th in MEI's conference series, which have continued to grow, Comminution '14 attracting 226 delegates from 27 countries (see full report and pictures, and comments from delegates, in posting of 23 April 2014).

Reflecting the need to reduce energy and increase the efficiency of comminution, we now have the backing of the Coalition for Eco-Efficient Comminution (CEEC) as Industry Advocate, and already 16 companies are providing major corporate support to what we are sure will be another opportunity for experts from around the world to discuss new ideas and common problems.
For the first time we will be inviting plant operators to submit short abstracts and to take part in a session devoted to short presentations describing how innovative techniques have benefited their circuits. Operators can derive tremendous benefits by taking part in a conference such as this and highlighting their operations. As Clifford Mutevhe, of Anglo American Platinum commented: "Comminution '14 not only enhanced my knowledge but also helped me identify solutions to the milling circuit I manage. Some of the discussions we had, we have carried them forward as part of the business process improvements. I also managed to identify with a huge pool of knowledgeable people from across the world. I could not imagine communicating daily and interacting with people from SA, USA, France, Iran, China, Australia and various other countries. Some have become my friends, importantly."

Those who wish to present in the formal technical and poster sessions will also be required to submit draft papers before the conference. These unrefereed papers will be available to delegates on USB sticks. After the conference, authors will be invited to submit final papers, which will be peer-reviewed with a view to publication in a special issue of Minerals Engineering, the world's number 1 mineral processing journal. The deadline for abstract submission is the end of October.

Highlights of the technical sessions will be three keynote lectures from world renowned experts in comminution, Joe Pease of Mineralurgy Pty Ltd (posting of 15 January), Australia, Prof. Malcolm Powell of Australia's JKMRC, and Rob McIvor of Metcom Technologies Inc., USA (see posting of 1 June). Joe and Rob will also be presenting two workshops on the Sunday before the conference which will be of great value to plant metallurgical staff and management, grinding circuit equipment and material suppliers, and others interested in design and optimisation.

As always the conference will be held in Cape Town's Vineyard Hotel, its superb gardens under Table Mountain providing the perfect setting for the extended coffee breaks, lunches and happy hours, intended to give delegates the opportunity of relaxing and networking in the best of conditions.

The view from the Vineyard conference centre
Lunches will be served in the exhibition area, where 13 of the 23 booths available have already been reserved.

Last year at Process Mineralogy '14 we held the conference dinner at nearby Kirstenbosch Botanical Gardens and this was a great night of good food, wine and entertainment, so we look forward to the Comminution '16 dinner in this unique setting.

Kirstenbosch Botanical Gardens
All in all, a conference not to be missed and we look forward to seeing you at the Vineyard next April.

Thursday, 3 September 2015

Porthtowan to Chapel Porth

This is a superb short walk, only 1.3 miles, between two of Cornwall's most picturesque little coves. For those wishing to walk from Porthtowan I would suggest that you extend the walk for another half a mile and take the steep hike up the cliff from Chapel Porth beach to the iconic Wheal Coates (posting of 20 August ), its Towanroath pumping engine house arguably being the most photographed in Cornwall, as it is more accessible than the famous Crowns Engine houses at Botallack (posting of 16th April).

There is also much evidence of mining activity just north of Porthtowan, although little remains now of Wheal Charlotte, which was worked not very succesfully for copper in the early 19th century, except for a crumbling engine house and a few spoil heaps.

Apart from the steep climb up the heavily eroded footpath from Porthtowan, this is a fairly easy little walk, with some great north coast scenery, particularly looking down to the beaches of Porthtowan and Chapel Porth, and the superb view looking north when approaching Chapel Porth of the not too distant Wheal Coates.

Porthtowan beach

The crumbling remains of Wheal Charlotte

Descending to Chapel Porth, with the view of Wheal Coates across the valley

Chapel Porth beach

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