Sunday, 31 August 2014

Tall Ships in Falmouth

Tall Ships Falmouth 2014

Falmouth’s association with the sea and ships has been a part of Cornwall’s heritage for centuries, so it is not surprising that the town always gives an enthusiastic welcome to the sailing ships of bygone times. Fortunately  many of these vessels have been restored and looked after and they still ply the oceans, albeit in a different capacity, that of sail training.

Four days ago 46 Sail Training vessels from around the world, including 11 of the magnificent square-sail Tall Ships, arrived in Falmouth for four days of festivities culminating in the start of the race to London Greenwich this afternoon.

It has been a wonderful few days. Falmouth has been heaving with people who have contributed to a great festive atmosphere.

Crowds flock into Falmouth

Refreshments at the Chain Locker overlooking the inner harbour

Pre-race fireworks

Parade of Sail


A Postcard from Townsville

An email in from Jon, who left Falmouth on Thursday, and arrived in Townsville yesterday after a 40 hour journey:

This is the third AusIMM Mill Operators conference I have been to. After previously visiting Fremantle and Adelaide I am now in Townsville in North Queensland for this the 12th in the series. The venue is the Jupiters Hotel and as can be seen from this picture of me this morning on Castle Hill the surrounding area is incredibly beautiful.

The conference starts tomorrow but this evening there was a quick early registration drink reception before the GD Delprat distinguished lecture which was being given by John Ralston. This gave me a quick chance to catch up with some regular MEI delegates including Sergio Vianna and Chris Greet.

Alan Hitchiner (Evonik Industries), Peter Munro (Mineralurgy Pty) and Chris Greet (Magotteaux)

Diana Drinkwater (JKTech) and Sergio Vianna (FLSmidth)
If you are attending then be sure to come and see me, I’ll be outside the main hall by the AusIMM table with plenty of information on upcoming MEI Conferences.


Wednesday, 27 August 2014

In conversation with the Inspirational Brierleys

Corale and Jim Brierley in Cornwall, June 2014
We were priviledged to have two of the world's most eminent biohydrometallurgists at Biohydromet '14 in Falmouth. Husband and wife team Corale and Jim Brierley took very active parts in the conference, Corale delivering a keynote presentation, and Jim was one of the panel members in the final discussion on the future of biohydrometallurgy.

Corale also took the time to speak to the Cornwall Women in Mining Group about her life and career, from growing up on a cattle ranch in Montana to the present day running Brierley Consultancy LLC with her husband Jim. Amanda reported that Corale's tales of fluctuating successes and failures were a true inspiration.

Seattle, 2012
I first met Corale in Seattle in 2012 where she presented a fascinating Milton E. Wadsworth Award Lecture on the present and future of bioleaching applications at SME '12. I found the history fascinating, and had not realised that bioleaching had been around for the past 55 years. It was that lecture that inspired me to invite Corale and Jim to Falmouth for Biohydromet '14, which also led to Corale's appointment as biohydrometallurgy representative on the Editorial Board of Minerals Engineering.

Corale and Jim have prepared a joint biography for the Mining Foundation of the Southwest (USA) for their joint induction in December 2014 into the American Mining Hall of Fame (Medal of Merit award for transformative contributions to the mining industry) and have given us permission to share it via the blog. It's a fascinating story and indeed inspirational:

Jim was born and raised in Denver – the only child of an immigrant single mother. He developed an interest in science as he grew. This resulted in his choosing a major in Bacteriology at Colorado State University, graduating in 1961 with a Bachelor’s Degree.  Although Jim never considered himself an exceptional student, his CSU advisor encouraged and supported his application for graduate study at Montana State University.  Here, Jim had a unique opportunity to continue his studies and conduct research in Yellowstone National Park on microbial life in thermal springs for both his MS and PhD degrees.  The irony of this was that during his first trip at the age of 9 to Yellowstone Park on a family vacation he stepped in a thermal spring, badly burning his leg on the first day of the vacation. This unfortunate accident may have led in some odd way to his fascination with thermal springs.

Corale was born in Shelby, Montana – a small town located on the Canadian border. Her parents were sheep ranchers. When she was five years of age, the family, which included one older brother, relocated to a cattle ranch about 50 miles north of Yellowstone National Park in the southwestern part of Montana. Corale attended a one-room country schoolhouse in McLeod, Montana for grades 1 through 8, occasionally riding her horse, Betty, to school. She attended high school in Big Timber, Montana, graduating in 1963 with her class of 50 students. During the summers following her junior and senior years in high school, she worked in the Department of Microbiology at Montana State University in Bozeman under a fellowship from the Montana Cancer Society. There she met Jim, who was working on his graduate degrees. Corale started college at MSU in 1963, majoring in microbiology, and took a job as a student lab technician working for Jim’s major professor, Dr. Kenneth Temple, who earlier had discovered the microorganism, Thiobacillus (now Acidithiobacillus) ferrooxidans, which was long considered the workhorse of biomining.

Jim, Corale and Dr. Temple made frequent trips to remote hot spring areas in Yellowstone Park as part of Jim’s PhD research work. These were occasionally overnight trips in the winter, requiring snowshoeing, with one memorable summer-time trip to the grizzly-bear infested Hayden Valley/Mary Mountain area of the Park. Jim’s research on the contributions of bacteria to the chemistry of acid hot springs led to the discovery of the first high temperature (thermophilic), acid-loving microorganism that later became known as Acidianus brierleyi - named by German scientists in honour of Jim. This microorganism and its other closely-related ‘Archaea’ cousins are now central to the leaching of primary copper sulfide ores, principally chalcopyrite and enargite.

Working and experiencing Yellowstone Park adventures together, it was inevitable Jim and Corale would marry, which they did in December 1965, just months before Jim would start his first employment as an Assistant Professor of Biology at New Mexico Institute of Mining and Technology in Socorro. They moved to Socorro the summer of 1966 with Corale enrolling as a student at NMT majoring in biology. The irony of this was, because of the small size of the Biology Department, Corale had to take classes from Jim – and she didn’t always get the best grades in the class! Corale graduated in 1968 with a BS in Biology.
At NMT, Jim met Dr. Roshan Bhappu (American Mining Hall of Fame Medal of Merit Recipient, 2006) who introduced him to the mining community providing an opportunity to research microbial processes in bioleaching of copper in sub-marginal grade dumps.  Jim progressed through the academic ranks to become Professor and Chairman of the Department of Biology at New Mexico Tech.  This period was a time for enhancing his interest in applications of microbial processes for metals transformations, both leaching and sequestration.

Corale and Jim c1972
Corale enrolled in a Master’s program in Chemistry at NMT in 1970; her research was a study of the high-temperature microbe that Jim has discovered in Yellowstone Park. This research culminated with a MS degree in 1971 and the first “Brierley and Brierley” technical publication in 1973. In 1972 Corale began working at the New Mexico Bureau of Mines and Mineral Resources, a division of NMT, continuing bioleaching research, largely funded by the U.S. Bureau of Mines and supplemented with funding from other federal agencies.

Jim and Corale collaborated on bioleaching research over the subsequent decade, co-authoring a number of publications jointly and with other colleagues. Jim took a 6-month sabbatical leave in 1976 to work with colleagues at the University of Warwick and the Warren Spring Laboratory in England; simultaneously Corale took a leave of absence from the New Mexico Bureau of Mines and worked at the Royal School of Mines in London. This experience piqued Corale’s interest in getting a PhD degree, which she received in Environmental Science from the University of Texas at Dallas in 1981, after a sabbatical leave from the New Mexico Bureau of Mines.

Following her return from Dallas, Corale was approached by the venture capital community to form a company to develop biotechnology for mining. This company, Advanced Minerals Technology, was founded in 1982 and Jim was hired as the research director. The company was relocated from Socorro to Golden, Colorado in 1985 and employed some 23 scientists and engineers, who developed and patented technologies for bioleaching and metal removal from waste streams. The 1987 stock crash was devastating to the company; with little revenue and even less availability of investment capital, the company let go its employees, including the research director, and sold assets. Newmont Mining Corporation acquired most of the company’s hard assets, hired Jim as Chief Research Scientist and moved the lab and Jim to the company’s research facility in Salt Lake City, Utah in 1988. Jim’s mandate was to develop a biological process for processing low-grade gold ore in which the gold was locked in a sulfide mineral; the objective was to biooxidize the sulfide, exposing the micron-sized gold particles for subsequent extraction with dilute cyanide solution.

Corale followed Jim to Salt Lake City, taking a year off to manage the wind-down of Advanced Mineral Technologies, form a new company, VistaTech Partnership Ltd., to house the patents and co-edit a book, Microbial Mineral Recovery, with a colleague. In 1990 Newmont Mining Corporation hired Corale as Chief of Environmental Process Development. The job involved work at several legacy mine sites to manage acid rock drainage and contaminated waste rock and soils. Just 18 month after being hired the position was abolished when Newmont was forced to lay-off a number of employees during the “Sir Jimmy Goldsmith era of corporate raiding”.

In late 1991 Corale found herself looking for a new job. She was offered positions at several Department of Energy labs; however, her desire was to remain affiliated with the mining sector. Contacts with mining companies always led to the same response: “we aren’t interested in hiring you full time, but we have a strong interest in bioleaching and need some consulting advice”. Mining company and DOE contacts resulted in a steady stream of consulting work – so much work in fact there wasn’t time to look for a real job. Thus began a consulting career and the founding of Brierley Consultancy, which continues today. However, consulting presented a new problem. Jim and Corale had always collaborated on R&D and were long accustomed to bouncing technical ideas off each other. Now Jim was working on proprietary technology for Newmont and Corale was consulting on bioleaching technology, often under confidentiality agreements, for what could be considered Newmont’s competitors. Suddenly, communication between Jim and Corale on technical matters ceased.

In 1996 Newmont moved their research laboratory to the new Malezemoff Technical Facility in Englewood, Colorado where Jim continued with development of the company’s bioheap pretreatment for refractory sulfidic gold ores. This research led to a number of patents and publications and the commercial application of the technology at the Gold Quarry Mine in Nevada.

With the relocation from Salt Lake City to Highlands Ranch, Colorado, Corale continued her consulting work. In the mid-1990s there was strong interest in heap bioleaching crushed, secondary copper ores in northern Chile and Australia and biooxidation of sulfidic gold ores and concentrates, which led to a constant stream of consulting work throughout the world. Teaching short courses in conjunction with mining organizations provided the perfect venue to secure consulting clients among mining companies and financial institutions. Corale was inducted in 1999 as a member of the U.S. National Academy of Engineering for "innovations applying biotechnology to mine production and remediation". Academy membership is among the highest professional distinctions accorded an engineer and honors those who have demonstrated unusual accomplishment in the pioneering of new and developing fields of technology.

Jim retired from Newmont as Chief Research Scientist for Biohydrometallurgy in 2001, joined Corale’s consulting company and was inducted in 2002 as member of the U.S. National Academy of Engineering for “recognizing the potential of high-temperature biomining, and for innovative industrial biomining practices”. Once again Jim and Corale were able to seek each other’s advice on technical matters.

Many of the technical papers Jim and Corale published individually and together over the decades became the basis for the bioleaching technologies applied commercially today for copper and gold recovery. About 18-20% of the world’s copper is now produced using heap bioleaching of secondary copper ores and about 3% of the global gold production stems from the bacterial pretreatment of sulfidic-gold concentrates followed by cyanidation of the biooxidized residues.

Jim and Corale have received many professional awards over their long careers and both remain professionally active, providing consulting services to the mining and financial sectors, presenting papers and short courses, reviewing submissions for technical journals, and chairing and serving on committees and boards for the National Research Council and the U.S. National Academy of Engineering (NAE). After serving 5 years on the NAE council, Corale was elected in 2014 as NAE Vice-President to embark on yet another professional chapter.

Jim (2nd left) and Corale with Pieter Van Aswegen and Jan Van Niekerk at Biohydromet '14

More Conversations

Monday, 25 August 2014

Where are SAG mills going?

In our recent conversation, Prof. Alban Lynch was very sceptical about where semi-autogenous grinding (SAG) mills have gone, and thinks they have taken us along the wrong track. He feels that they may be attractive in terms of high productivity, but says that "their energy efficiency is poor, and I feel that these immense machines are going to turn into very large ball mills".  Developments in fine crushing machines may turn out to be viable alternatives to SAG mills.

Interesting, as in a recent article in Mining Magazine (July/August 2014, pp. 27), Kurt O'Bryan of Weir Minerals says that, although SAG mills have been around for over 40 years, the demand to process more ore in less time is a key factor in where comminution trends are heading.  He says that "SAG mills have to be bigger to meet these demands. Some are up to 12.1-12.8 m in diameter in order to handle the higher tonnages, and the size of these mills makes them harder to install and operate efficiently".

He says that Weir is seeing a rise in demand for larger cone crushers that are matched with large high pressure grinding rolls (HPGRs) for customers who want to replace SAG mills in order to increase efficiency. Utilising cone crushers and HPGRs allows ore to be processed from 250mm to 50mm in cone crushers, then down to less than 6mm from HPGRs. O'Bryan also explains that "the interparticle comminution inherent in the HPGR process is uniquely efficient relative to other forms of comminution in crushing or milling".

So what do the operators think? Do you have problems with SAG mills, and how do you view their future? Is finer crushing a viable alternative? And no doubt the manufacturers will have something to say?

Two major conferences just a week away

MEI is a media partner for two conferences which start next week, one in Australia and the other in South Africa.

The AusIMM's Mill Operators' conference will be held in Townsville, Queensland. Jon Wills will be representing MEI, so please share your news with him as he will be reporting on the event for MEI Online and the blog.

Similarly look out for UCT's Dr. Megan Becker at the General Meeting of the International Mineralogical Association (IMA 2014) in Sandton, South Africa. Megan will be representing MEI and reporting for the blog in her capacity as consultant to MEI's Process Mineralogy '14 conference.

Saturday, 23 August 2014

The Chilean IMPC is fast approaching

MEI is a media partner for this year's IMPC, which is now only 2 months away. I will be there representing MEI and preparing a pictorial report on the congress as in previous events (see posting of 30 September for report on the previous IMPC).

This year Chile is the host country of the XXVII International Mineral Processing Congress – IMPC 2014, to take place between October 20 and 24 at the Sheraton Hotel in Santiago in the context of “optimizing water and energy for sustainable mining.”

The Sheraton (centre) at San Cristobal
The IMPC has become the most prestigious global forum in promoting scientific and technical knowledge in mineral processing and extractive metallurgy. The congress was initiated in 1952 in the UK and since then has taken place periodically around the world. This year the meeting expects to bring together over 1,000 professionals and academics from the mining industry, representing approximately 50 countries.

“It is extremely valuable for professionals to have this space to come together and talk about their experiences with production and management processes, compare capacities obtained while using the latest technologies, and discuss solutions that have been found when facing certain problems posed by the ore, whose grades are diminishing more and more,” said Professor Juan Yianatos from the Universidad Federico Santa María, President of the IMPC 2014.

Over 500 articles by authors from 50 countries have been received for the congress. The papers will be published in the Congress Proceedings and presented at the event. Additionally, there will be a Sustainability Symposium, organized by the Sustainability Commission of the IMPC Council.

The technical sessions will cover the following topics: comminution; flotation; physical separation processes; water and tailings management; energy efficiency; control and process optimization; process geometallurgy and mineralogy; hydrometallurgy; concentrator plant operation and project development; urban mining; human capital; sustainability and mineral economics.

The congress is organized by Universidad de Chile, Universidad de Concepción, Universidad Técnica Federico Santa María, Chilean Council of Engineers, and Gecamin- the leader company in developing technical conferences for the mining industry.

Friday, 22 August 2014

Cornish Mining Sundowner- August

Around 25 people attended last night's sundowner on a cool, dry evening in Falmouth.


The next sundowner will be on Thursday September 18th, and as always there is an open invitation to join us at Falmouth's Chain Locker if you are in the area at that time.

Wednesday, 20 August 2014

Automated Mineralogy continues to make big strides

Automated mineralogy has evolved rapidly over the past few years, with many new major players providing alternatives in a very competitive market.

A few months' ago Will Goodall and Al Cropp of MinAssist, called in at MEI. They were both involved with Intellection in the early days of QEMSCAN technology.

I was pleased to hear last week that Will's company MinAssist is the latest sponsor of Process Mineralogy '14 in November.

Al Cropp has since moved on from MinAssist, and is now with Carl Zeiss, also a Process Mineralogy '14 sponsor. Only a couple of weeks ago Zeiss launched a new automated mineralogy system for the mining industry, which is described on MEI Online. The new system will be on display at the conference, so I look forward to catching up with Al, and with Will, in Cape Town in November.

Al Cropp (seated) with the new Zeiss instrument

Monday, 18 August 2014

Call for Abstracts- Physical Separation '15 and Computational Modelling '15

Abstracts are now invited for two of MEI's small specialised conferences, which will run back to back in June next year. As with all MEI Conferences, papers accepted for presentation will be published on a Proceedings flash drive, available at the conference, and then authors will be invited to submit edited papers to Elsevier Science after the event for peer-review and publication in a special issue of Minerals Engineering, the world's highest ranked mineral processing journal. Both conferences are certified for Continuous Professional Development.
With its very long evenings June is a great time to be in Cornwall, so plan ahead and aim to spend some time exploring this beautiful area of the world.

 Computational Modelling '15 will be the 5th in this very specialised but popular series and as always the aim of the conference is to bring together both users and developers of computational modelling from academia and industry to share their knowledge and expertise (see report on the 2013 conference). This conference is aimed at the full spectrum of people involved in computational modelling in minerals processing and materials handling, from model development, validation and all the way through to application.
The specific areas include:
• Model development and computational techniques
• Modelling of minerals processing and materials handling unit operations
• Optimisation of plant and circuit operation and design
• Experimental validation including novel experimental techniques
Physical separation methods are ubiquitous, and there is no mining operation in the world which does not make use of the density differences between solids and liquids. Whether it be gravity concentration, classification or dewatering, the principles of separation are essentially the same and Physical Separation '15, the 3rd Physical Separation conference, will bring together researchers and operators who have common interests in:
• Gravity concentration methods - single and multi-G separators and dense medium separation
• Classification techniques - hydrocyclones, air classifiers etc.
• Solid-Liquid Separation - thickeners, clarifiers etc.
• Papers dealing with magnetic separation, and electronic sorting
• Microwave technology. There are many aspects of mineral processing where the use of microwaves has potential and papers dealing with the enhancement of physical processes by microwaves are encouraged.
The keynote lecture Reducing energy consumption in comminution by doing much less of it! will be given by Dr. Rob Morrison of JKMRC, Australia, who will discuss the potential of physical separation methods, particularly electronic sorting, within comminution circuits.
Cornwall, the “birthplace of modern mining”, is an appropriate place to hold such an event, as this was the first place in the world where physical separation methods were practiced on a large scale, and the programme will include a visit to the historic Camborne-Redruth copper and tin mining district, where ruins of 19th century ‘dressing floors’ can be explored (see also the report on the 2013 conference).

If you would like to present a paper at either of these meetings, please submit your short abstract by the end of December of this year. If your company is interested in exposure via sponsorship, details for Computational Modelling '15 can be found here, and here for Physical Separation '15.

Friday, 15 August 2014

A brief history of classification in grinding circuits

In our recent discussion, Prof. Alban Lynch expressed an opinion on the use of hydrocyclones in closed grinding circuits: "the way they are used now is an absolute nonsense, with circulating loads in some cases of well above 200%. The future is high frequency screens". This has led, unsurprisingly  to a few comments on the use of hydrocyclones and screens in milling circuits.
Prof. Lynch has been in touch this morning by email, and asks me to publish this short technical note, which he entitles Classification – the enigma in mineral processing.
An enigma is defined as a puzzling or inexplicable occurrence. The description fits the present position of wet classifiers well. We need to grind increasing amounts of low grade, harder ores to meet the demand for metals so the expenditure on mills and understanding breakage is high. Classifiers can limit circuit productivity by 10% or more yet there seems to be relatively little expenditure on ensuring that size separation in classifiers is accurate and efficient. Knowing the past is the starting point for doing better so I will briefly review the story of cyclones and size separation.
 Cyclone classifiers have been used in dry and wet grinding circuits for decades. The hydro-cyclones used in wet circuits are small, inexpensive, easy to operate, and handle changes in throughput without difficulty.  Their disadvantage is that their separation characteristics are poor and they can produce recycling loads up to 400% although the particles which require regrinding may comprise only a small fraction of this. These high loads limit the capacity of mills to grind new feed and reduce the sharpness of the split, both of which may be costly. The problem occurs in both dry and wet processes and the different approaches used in the cement and ore industries to operating centrifugal separators will be discussed.      
In cement circuits the Askham dynamic separator was used for many years from 1885. It was superior to static cyclones but the circulating load was high and to reduce it a second generation centrifugal separator was designed and built in 1960. Further reduction in the load was still needed to reduce the grinding cost further and a third generation separator was designed and built in 1985. The improvement which has occurred over three generations is shown in the table and figure below.

There was intermittent interest in hydro-cyclones for wet circuits from 1891 but the Dorr rake classifier became available in 1902 and this unit and the Akins spiral classifier were used for wet classification from 1900-1950. By then the post war minerals boom had started and this required higher capacity processing units. Hydro-cyclones were of interest because pumps were available which could create high velocity spiralling flows in cyclones and these flows provided a mechanism to separate the feed into coarse and fine streams. Performance of hydro-cyclones improved when Kelly Krebs designed the involute entry which reduced disturbances in the outer spiral.                                                                                                      
Since then the strategy to handle high capacities of grinding circuits has been to build nests of hydro-cyclones and larger hydro-cyclones and these have been effective in handling high flows. But only with high frequency screens does there seem to have been much emphasis on better separation. These screens have been successful in reducing circulating loads and improving the sharpness of separation in 300 tph grinding circuits at the Apatit mine in the Kola Peninsula, Russia.             
Screens are more expensive than hydro-cyclones and their capacity limits must be observed during operation. But these limits will be extended and they will be an important part of the future of wet classification.  

Wednesday, 13 August 2014

News of South-West England minerals people

Nick and Felicity (Flee) Wilshaw of Truro-based Grinding Solutions Ltd joined us for lunch today. Offering technical, marketing and investment consultancy, as well as laboratory testing facilities, to all fields of mineral processing, their company is particularly recognised throughout the industry as a leader in ultra-fine grinding. As such Grinding Solutions was a sponsor and exhibitor earlier this year at Comminution '14.

With Nick and Flee at MEI
Now they are seeking to broaden their flotation capabilities, and this week Jon's partner Dr. Kathryn Hadler, formally with Imperial College, joined the company to strengthen the expertise in this area.
Kathryn with IMPC Chairman Cyril O'Connor, Cape Town 2011
A very good friend of Nick and Flee is Charlie Northfield, Process Plant Manager at the new tungsten mine, Drakelands, in Devon. Charlie and Nick graduated from Camborne School of Mines with degrees in Mineral Processing Technology in 1980. Following on the success of the monthly Cornish Mining Sundowners in Falmouth, Charlie has initiated a Devon Sundowner, and has sent me the photo below, taken at the inaugural sundowner on 1st August, attended by Wolf Minerals employees, with guest of honour Andrew Sarosi, former Chief Metallurgist, Hemerdon Project, AMAX Exploration UK.
1st Devon Mining Sundowner. Andrew Sarosi 2nd left, Charlie Northfield 2nd right
The Sundowners are planned to be held on the first Friday of every month from 5pm at the Miner’s Arms, Hemerdon. Anyone involved in mining and related industries is welcome.

Monday, 11 August 2014

In Conversation with Alban Lynch, the first Director of the JKMRC

International Mining magazine's inaugural Hall of Fame took place this year at the SME Annual Meeting in Salt Lake City. Among the legends of the minerals industry profession who were honoured was Prof. Alban Lynch, one of the giants of comminution. This was one of many awards that he has received in his long and distinguished career. He is an Officer of the Order of Australia, and in 2010 in Brisbane received what is considered to be mineral processing's top award, the Lifetime Achievement Award of the International Mineral Processing Congress.
Alban Lynch (left) receiving the IMPC Lifetime Achievement Award
from Eric Forssberg, Brisbane 2010
I first met Alban in 1986 when he presented a keynote lecture at the NATO ASI in Falmouth. He and his wife Barbara live in Brisbane, and I phoned him recently to talk about his career and to hear his views on modern mineral processing and how he sees the future progression of our industry.
Alban Lynch was born in Queensland in 1930 and worked as an industrial chemist in the paint industry from 1947-1953, while studying part-time for a Diploma in Chemical Engineering from Sydney Technical College. After graduating in 1954 he took up a position as a metallurgist at Zinc Corporation, Broken Hill, as his fiancée Barbara was from there, and studied for a BSc and MSc as an external student at the University of New South Wales.
He spoke about Maurice Mawby who came from Broken Hill, and described him as "one of the real greats". Mawby was very much involved with the development of flotation and he ascended from metallurgist to Chief Executive and set up the great years of Conzinc Riotinto Australia, which became Rio Tinto Australia. Alban remembers him as a man with a remarkable memory who would walk around the plant at Broken Hill recognising everyone and asking about their families. It must have rubbed off on Alban, as this is exactly what T.C. Rao, who obviously had great respect and affection for him, said about him in our recent conversation. Alban remarked that he and Rao "had many an argument on a Sunday afternoon, which Rao always won!"
In 1958 Alban joined the Dept. of Mining and Metallurgical Engineering at the University of Queensland (UQ), where he would remain for most of his long career, spending the first 12 years as a Research Officer for mineral processing operations, and being awarded a PhD in the department in 1965.
His arrival at UQ was at an opportune time, as by 1960 the first mineral boom in 30 years was forming and in 1961 the Australian mineral industry, through the newly formed Australian Minerals Industry Research Association (AMIRA), established by Maurice Mawby, decided to fund jointly sponsored research to improve mining and mineral processing technology.  Mawby had set up a special projects laboratory at Broken Hill, which he staffed with 12 engineers, as he knew that technology had to change in the mining industry. In 1962 a three year AMIRA project on grinding started at UQ with a group consisting of Alban, two graduate students and two technicians. The theme of the research became the modelling and simulation of grinding circuits. Jim Foots, the General Manager at Mount Isa Mines Ltd, supported the work by permitting the circuits in its old concentrator to be experimental test sites and this was the start of the tradition of project research being plant based and of graduate students, including T.C. Rao, spending months at plants on thesis projects which had the objectives of improving local circuits and providing data to support the general programme on modelling and simulation. Funding of the project has been renewed periodically for 50 years, in what is now the P9 project, although changes have occurred in its scope and size.
By 1967 mathematical models had been developed for rod mills, ball mills and hydrocyclones and simulation of a copper circuit containing one rod mill, three ball mills and six hydrocyclones indicated a proposed rearrangement which, when made, resulted in a large increase in capacity. Similar simulation work with the rod mill, 2 ball mill, 2 rake classifier circuit at Zinc Corporation in Broken Hill had a similar result. By this time Bill Whiten had joined the group and brought much needed computing skills. During the next seven years research extended to modelling of crushers and screens at Mount Isa, autogenous mills at Tennant Creek, and banks of flotation cells at Mount Isa and Philex Corporation in the Phillipines, and to the control of grinding circuits using a PDP8/I computer provided by AMIRA. This culminated in the publication of one of Alban's most well known books, Mineral Crushing and Grinding Circuits.
Alban Lynch with AMIRA computer, early 1970s
In 1971 the research group was given strong encouragement by MIM Holdings Ltd when the company established the Julius Kruttschnitt Mineral Research Centre (JKMRC) to be its Brisbane base, with Alban Lynch its first Director, a position he held until 1989, when he handed over to Dr. Don McKee, allowing Alban to concentrate on his new role as UQ's Professor and Head of Mining & Metallurgical Engineering, a position he held until 1993. (Click here for a biography of Julius Kruttschnitt, who Alban regards as another outstanding figure in the history of Australian mining). 
By 1974 the modus operandi of the JKMRC group was well established and its research activities in modelling were extended to coal flotation in the Bowen Basin mines and crushing at the Mount Newman iron mine and the Bougainville copper mine. The establishment of the JKMRC made Alban "realise the importance of graduate students working in plants- to get anywhere in mineral processing you don't spend your time fiddling around in laboratories and the students realised that this was a great opportunity for them, and the mines were very supportive".
In 1975 the decision was made to extend modelling research to blasting because that was the first in the sequence of size reduction processes. The feasibility study was carried out with support from Mount Isa and Mount Newman and the blasting project became a large and long running AMIRA project. The research was very useful to blasting engineers but it was many years before the link between blasting and crushing and grinding was developed. Alban strongly believes that mineral processing in the future needs to be linked to mining, and he talked with enthusiasm of UQ's Gideon Chitombo, a Zimbabwean "who is a superb public speaker, and who is also wrapped up in the future of mining and has set up projects funded by many major mining companies". Gideon recognises that mining must take into account mineral processing, and he will be presenting a plenary lecture on this, hopefully followed by a forum, at the IMPC in Santiago in October.
By 1980 models of grinding and flotation circuits were well developed and another book was published Mineral and Coal Flotation Circuits, co-authored with N.W. Johnson, E.V. Manlapig and C.G. Thorne. Many short courses were given on modelling, but simulation could not be used widely because engineers did not have easy access to bureau type computers. Personal computers were becoming available so a project was established to put the models on a PC. To demonstrate the validity of the modelling work and debug the programme the engineer who wrote the software spent 6 months with the PC at plants of AMIRA sponsors in USA and 6 months with sponsors in Australia. This was the origin of JKSimMet, which he feels was so successful because "a guy called Dave Wiseman wrote it. He had a lot of experience at Mount Isa, so he knew what was needed from a simulator". Knowing Dave well, I could understand Alban's praise for him, and his ability to keep things simple, a failing of many modern models, which have become so complex and difficult to understand that they are not easily accepted by operators. I remarked that often at conferences I get the impression that academics are talking to each other, but that the people at the 'sharp end' are not truly involved.

Dave Wiseman keeping it simple for me in Seattle, 2012
It was interesting to hear that he is "very sceptical about where SAG mills have gone, I think they have taken us along the wrong track. They may be attractive in terms of high productivity, but their energy efficiency is poor, and I feel that these immense machines are going to turn into very large ball mills". 
Although he has been involved with hydrocyclones for very many years he feels that "the way they are used now is an absolute nonsense, with circulating loads in some cases of well above 200%. The future is high frequency screens". He and Hakan Dundar from Hacettepe University, Turkey, have analysed data from several large operations and "it is very clear that these screens are so much better than hydrocyclones and there will be a paper on this at the IMPC in October". It is interesting that the new tungsten mine in UK will be operating their ball mills in closed circuit with Derrick screens, rather than hydrocyclones, and we will be hearing more of this at Physical Separation '15 in Falmouth.
After 6 years as Head of Department at UQ. Alban spent a large portion of the next 15 years lecturing on modelling and setting up research programmes in other countries, notably in Malaysia, Brazil, Mexico and Turkey. The most successful was concerned with cement clinker grinding in Turkey where the research group has expanded from one graduate student in 1999 to 3 staff and 8-10 graduate students in 2009. Following the pattern developed at JKMRC the dry grinding group at Hacettepe University works closely with the cement industry and is expanding its activities into related areas.   He regards Hacettepe as being "far and away the best mineral processing University in Turkey, for exactly the same reason as why the JKMRC became so successful- the students are prepared to go out on plants and actually do the work, whereas this does not happen at the other Turkish Universities".
He also found time during this period to co-author two more books, in 2005 The History of Grinding, with Chester Rowland, and the latest in 2010, The History of Flotation with Greg Harbort and Mike Nelson.

Launch of History of Flotation at the 2010 IMPC in Brisbane,
with Mike Nelson and Greg Harbort
His latest project is a Handbook on Comminution, with the AusIMM, which he hopes will be available at Comminution '16 in Cape Town. He is also involved, with the AusIMM, in the development of a virtual museum at Broken Hill, recording the town’s mining industry and its great contributions to mineral processing technology.
Talking to Alban Lynch was a great pleasure and privilege and I hope that his interesting views on mineral processing will lead to some open debate.

More Conversations

Saturday, 9 August 2014

The Valleys- the Heart and Soul of Wales

Barbara and I are back in Cornwall after a few interesting days in South Wales, once one of the great coal mining areas of the world, prior to the mass closure of UK coal mines in the mid 1980s. At its peak in 1913, 57 million tons of coal were dug out of the hills by 232,000 men and boys working in 620 mines. 
Blaenavon main street
We based ourselves in Blaenavon, a World Heritage Site, and almost certainly the best preserved example of a traditional South Wales iron-making town. Although part of the town dates from the late 1780s, most of the buildings are representative of an early mid-Victorian Welsh industrial community with much of it built before 1870.
 Blaenavon lies on the very edge of the South Wales coalfield, above the valleys of Ebbw Vale and Merthyr Tydfil, where seams of coal and bands of iron ore are shallow and outcrop on a hill overlooking Abergavenny.

There were many coal mines around Blaenavon, and Big Pit was one of them. Sunk sometime between the late 1830s and 1860, by 1870 the Blaenavon Iron & Steel Coal Company was the second largest coal producer in South Wales, employing 1300 workers in its heyday. It closed in 1980 and three years later was opened as the excellent Big Pit National Coal Museum, which I cannot recommend highly enough.

Big Pit National Coal Museum

The underground tour, with guides who were former miners, is an eye-opener to life underground in a working coal mine, and the visual displays are magnificent.


Nearby is the Blaenavon Ironworks museum, equally impressive. The ironworks was built in 1788 and in 1812 the furnaces were claimed to be among the most productive in the world. The site became a highly integrated ironworking operation where the mining of coal and iron ore took place alongside the smelting and forging processes.

It was here that Sydney Gilchrist Thomas made one of the last major breakthroughs in steel making in the 19th century. In 1878 he and his cousin Percy discovered how to remove phosphorus from steel, which revolutionised steel making in Europe and America.

By one of the huge iron furnaces
Coal mining is a hazardous business and many lives have been lost in South Wales collieries, but no mine disaster has been so tragic as the one that occurred in the tiny village of Aberfan in October 1966, when an avalanche of colliery waste buried part of the village. Torrential rain brought the waste down onto several buildings, engulfing the Pantglas Junior School, where morning lessons had just begun. 144 people were killed, including 116 children. Today the school site is a garden of remembrance to this disaster which perversely brought the valleys worldwide attention.

Although Wales is renowned for its mining, it is also famous for its many castles, 641 of them, some built to keep the English out, others built by the Normans and Plantagenets to keep the Welsh out. We visited the 13th century castle at Caerphilly, the largest castle in Wales, and second largest in the UK after Windsor, and only 25 miles from Blaenavon. Its most dramatic feature has to be the tower that 'out leans' Pisa! 

Caerphilly Castle
Returning to Cornwall we spent a few hours in the Welsh capital, Cardiff, and visited its castle, with its 13th century Norman motte and keep.

Cardiff Castle

Wednesday, 6 August 2014

Great news for Minerals Engineering

The 2013 Journal Impact Factors have been published, and I am pleased to see that Minerals Engineering is once more the highest ranked mineral processing journal, being second only to Elsevier's specialised journal Hydrometallurgy.

I am not exactly dancing for joy at this news, however, as I have never been a great fan of the capricious impact factor ranking, although I know it is of great importance to many academics. A more important guide for me is journal usage, the number of downloads that journal papers receive on ScienceDirect, and for Minerals Engineering, that is truly enormous. In 2013 a record 260 papers were published (compared with 212 in 2012) and there was also a record number of downloads from ScienceDirect, 460,961, the most downloaded paper in 2013 being A review of the beneficiation of rare earth element bearing minerals (Jordens, A.; Cheng, Y.P.; Waters, K.E.). The journal's rejection rate in 2013 was 63%.

What I am particularly pleased with is the figure below, which benchmarks the journal's performance on the basis of feedback from the most important people who contribute to the journal's success, the authors.

The Author Feedback Program is a continuous research program monitoring the performance of Elsevier's primary journals. It allows Elsevier to closely monitor author opinion and thus journal performance. Authors are invited to rate a number of statements concerning their publishing experience. These statements are grouped into areas, including reputation, peer review, production speed, publishing services, the editorial board and impact factor.

Elsevier also asks each author to rate another journal in which they have recently published.  The score for each area for Minerals Engineering is then compared against the average of all other titles. The "average", which is a convenient benchmark, is zero on the chart. Scores above zero mean, for that area, that Minerals Engineering is rated higher than average. Conversely, factor scores below zero, mean for that area, Minerals Engineering is rated lower than average.  The order in which the factors appear in the chart denote their importance to authors (i.e. the first factor listed is, on average, the most important consideration when deciding where to publish for the authors of the journal).

The overall result is impressive and I would like to take this opportunity of thanking all those who work with me to maintain Minerals Engineering's consistently high standard; the Editorial Board, supplemented by around 275 reviewers, who give up their valuable time to contribute to the peer-review process, my excellent Publishing Manager at Elsevier, Dean Eastbury and his very helpful team, particularly Divya Kaliyaperumal who deals patiently with all production problems, and last but by no means least, all the authors who submit their valuable research work to the journal and the associated MEI Conferences.

Monday, 4 August 2014

Two interesting keynotes to look forward to at Process Mineralogy '14

Process Mineralogy '14 is only 3 months away, and the technical programme contains papers by authors from 16 countries. The two keynote lectures will be presented by top scientists from Sweden and UK. 
Prof. Pertti Lamberg, of Luleå University Sweden, will identify a way forward in process mineralogy, utilising automated mineralogy for modelling and simulating beneficiation processes (see posting of 16 May 2014).
Bernd Lottermoser
The second keynote "Predicting acid rock drainage: past, present, future" by Prof. Bernd Lottermoser, who has a Chair in Environmental Geochemistry at the University of Exeter, Cornwall, UK and is also Visiting Professor at the University of Tasmania, Australia, deals with a highly topical subject. Mine wastes such as waste rocks, tailings and heap leach residues often contain abundant sulphide minerals that may oxidise and dissolve to generate acid rock drainage (ARD) water, with the oxidation products potentially impacting on ecosystem and human health. Total worldwide liability associated with the current and future remediation of ARD is approximately US$ 100 billion. Consequences of failing to predict ARD for individual operations and for the mining industry include unplanned spending on remedial measures and reputational damage. Despite these severe risks, predicting the properties of mine wastes is typically not an attribute which is strongly embedded into the development of mineral resources, and examples of failures to predict waste properties accurately are plentiful. Moreover, the tests currently used for the characterisation of mine wastes still have serious limitations, are riddled with uncertainties that are hard to quantify, or only allow predictions that represent the best estimate of what might happen in the future. Also, today’s mine waste classification schemes are far too simple, blinded by chemical data and obsessed with chemical analyses.
Prof. Lottermoser will show how the time has come to drastically improve our scientific efforts to forecast the likelihood of ARD accurately. Improvements in our predictive capabilities will come from new field and laboratory tests and the application of state-of-the-art characterisation tools and methodologies at individual exploration and mine sites. Such data are needed to establish the operational challenges, impacts and closure liabilities of ores and wastes.

Saturday, 2 August 2014

A very memorable evening on the Singapore River

You may recognise a few people on this short movie, taken at the Minerals Engineering '91 conference dinner in Singapore over 23 years ago.

The evening boat trip on the Singapore River was memorable, not only for the people who attended, but also for the multitude of microorganisms, waiting to pounce, in all the delicious food which was served.  Over half the delegates failed to show the following morning, due to a mass bout of food-poisoning!