Friday, 20 October 2017

Grinding Solutions Ltd hosts an impressive October Mining Sundowner

The October Cornish Mining Sundowner in 2015 was hosted by Grinding Solutions Ltd (GSL) to showcase their new premises at Tresillian just outside Truro (posting of 23 October 2015). Two years later we were hosted once more last night by GSL to celebrate the opening of their recently extended laboratory and office facilities, and also to meet their continuingly expanding team. As last time, the event was very well attended, by over 100 people, with representatives from across the industry including equipment suppliers such as Metso, partners including Petrolab and other mining companies based in Cornwall. The Camborne School of Mines was also well-represented, with a number of trustees and a strong contingent of students.

Grinding Solutions originally specialised in fine grinding but in recent years has been applying its innovative and consultative approach to areas including  process mineralogy,  flotation and  gravity separation. The new facilities will accommodate an all new  biohydromet and cyanide leaching lab which are being set up with input from Dr Chris Bryan and Dr Dave Dew from the Environmental and Sustainability Institute, Camborne School of Mines, University of Exeter.  The fast-growing Cornish company, with an international client base, has further plans for expansion in the future. Equipment on display included a wide range of mills such as the Metso SMD test mill, a LME4 IsaMill, the Magotteaux Mill, as well as 10mm to 5” hydrocyclones, and Denver, Wemco, Magotteaux and FLSmidth flotation cells.
 A few photos are posted below, and I have added names where I can.
Two long serving Metso staff, and CSM graduates Andy Wilkinson (2nd left)
and Graham Davey (4th left). Far right is James Strongman of Petrolab Ltd

2nd left is Chris Bryan, MEI consultant to Biohydromet '18


Flee Wilshaw of GSL with Linda Matthews, Paul Burton and Alan Matthews

Jim Turner, KP van der Wielen, Nick Wilshaw, BW, Paul Morgan and Bentley Orchard

Flee Wilshaw, Tony Clarke, Barbara Wills with Dennis Murphy, CSM graduate
who recently retired after over 30 years with Johnson Matthey
Thanks again to Nick and Flee Wilshaw and their staff at GSL for their hospitality. We look forward to seeing Nick and Flee at Flotation '17 next month, and GSL are one of the sponsors of Comminution '18 in Cape Town in April. They will also be represented at Biohydromet '18 in Namibia.
Flee and Nick Wilshaw and the GSL team
Twitter @barrywills

Monday, 16 October 2017

A new journal and a new generation

On January 1st a new look Minerals Engineering will be launched, as a result of its merger with the International Journal of Mineral Processing (IJMP).  Since the inception of Minerals Engineering in 1988 I have been Editor (see also posting of 8 June 2013), and 3 years ago a dynamic young researcher, Dr. Pablo Brito-Parada, joined me as Associate Editor, to assist with the ever increasing paper flow.
Times are changing and the editorial structure of the hybrid journal will be dominated, quite rightly by a new generation of young minerals engineers. My position now is as Editor-in-Chief. Pablo is promoted to Editor, and is joined by Associate Prof. Kristian Waters, former editor of IJMP.
Pablo Brito-Parada is a Research Fellow in the Department of Earth Science and Engineering at Imperial College London. His research focuses on industrial multiphase flows, particularly in mineral processing, combining experimental techniques and numerical modelling for equipment evaluation and design. A Chemical Engineer by training, he worked in academia and industry in Mexico before moving to the UK, where he completed his PhD in froth flotation at Imperial College London. He has since coordinated industrial flotation optimisation campaigns, led the flotation research at the Rio Tinto Centre for Advanced Mineral Recovery as well as other mineral processing research projects. He is currently Principal Investigator at Imperial College for IMPaCT, a €10m consortium funded by the European Commission with the objective of developing solutions for small scale sustainable mining in Europe.
Kristian Waters is an Associate Professor at McGill University, Canada. He has an M.Eng. in Chemical Engineering with German from UMIST, UK, an MSc in Instrumentation and Analytical Science also from UMIST and PhD in Chemical Engineering from the University of Birmingham, researching into the effect of thermal treatment on the physico-chemical properties of minerals He then spent 2 years as a post-doc at Imperial College London working with Prof. Jan Cilliers on fine particle flotation and PEPT.  In 2009 he moved to McGill as Assistant Professor, and was awarded tenure in 2015. His current research is quite varied, covering the majority of separation techniques and some water treatment, his recent research targeting the beneficiation of rare earth bearing minerals.
Pablo and Kristian will be aided by six Assistant Editors: Grant Ballantyne, University of Queensland, Australia; A. Deniz Bas, Laval University, Canada; Erin Bobicki, University of Toronto, Canada; Zoltan Javor, Aalto University, Finland, Anita Parbhakar-Fox, University of Tasmania, Australia; Martin Rudolph, Helmholtz Institute Freiberg for Resource Technology, Germany.
None of the 8 editors and assistant editors were born when the International Journal of Mineral Processing was founded by eminent sampling statistician Pierre Gy in 1974, the year that I started my 22 years at Camborne School of Mines. Mineral processing itself has seen great changes in those 43 years, and in fact only became a discipline in its own right at the beginning of the 20th century.
Prior to the industrial revolution of the 18th and 19th centuries the demand for metals was not very high. The small county of Cornwall in south-west England was the major producer of copper and tin in the mid 19th century, when world production of copper was about 60,000 tonnes per year, compared with around 20 million tonnes now. The copper ores were of very high grade and needed little upgrading, apart from simple hand sorting by bal maidens, female workers who worked the surface plants. Tin ores did need crushing and grinding, in stamp mills, prior to gravity concentration in crude devices such as buddles and rag frames.
The 'discovery' of electricity had a profound effect on metal demand, particularly for copper, and soon the main source of supply was from the vast deposits discovered in the Americas and Australia. By the beginning of the 20th century the demand for metals and minerals had become so high that the 'easy' ores were becoming scarce and the simple sorting and gravity methods could not adequately treat the ever decreasing grades and complexity of the vast quantities of mineral deposits which were available.
The mining industry was in crisis, and so was the industrialised civilisation, although most people would not have been aware of this. The search was on for an innovative method of upgrading the low grade base metal ores, and the great saviour of the mining industry was froth flotation. The invention of modern flotation is attributed to Francis Elmore, who patented a vacuum flotation process in 1904, which was used in the Zinc Corporation plant in Australia for 6 years, although the first recognisably "modern" flotation technique had been patented in London in 1903 by Sulman and Picard, and this used air bubbles formed by forcing compressed air through holes in the cell, but it would be years before such pneumatic cells would be commercially used. By 1908 flotation was working well for bulk flotation of zinc tailings, but the search was then on for means of treating primary sulphides, which led to the development of xanthate collectors, selective activators and depressants, and, as they say, "the rest is history". Just as it is difficult to overestimate the importance of the mining industry, so it is difficult to overestimate the value of froth flotation to modern society. How would we economically produce the metals and minerals that modern society cries out for without this process, which I have always referred to as the most important technological development since the discovery of smelting? Throughout the century, as the available ores became leaner and more complex, so flotation was adapted to effectively deal with them, and to this day research both into the physical and chemical aspects of flotation continues unabated.
There were also innovations in comminution in the early years of last century, with inefficient and energy consuming stamp mills being replaced by tumbling mills, which could be run in closed circuit with classifiers to control product size, so by the 1930s mineral processing flowsheets typically consisted of comminution in cone crushers and rod mills, and long lines of ball mills running in parallel, followed by banks of small flotation machines also running in parallel. By 1974 there had been innovative new processes, such as high intensity magnetic separation, the first enhanced gravity separators, and the first column flotation cells, and in extractive metallurgy hydrometallurgical techniques such as leaching, solvent extraction and ion-exchange with electrowinning were found to be viable options to traditional smelting. However typical mineral processing plants would have been instantly recognised by pre-war operators, as lines of small mills and flotation cells still dominated.
The biggest impact on minerals engineering was the rapid development, and increase of computer power in the 1980s, which has led to the simulation models that are used today, and the development of DEM, CFD etc. But perhaps more importantly powerful computers led to sophisticated methods of controlling mineral processing operations automatically and this in turn led to designers looking to overcoming the problems associated with replacing many small machines with fewer very large machines which could be more easily instrumented and controlled, and the trend for larger and larger flotation machines and grinding mills continued into the present century. Comminution in particular has seen major changes this century, with the development of high pressure grinding rolls (HPGR) and stirred mills, and it may be that these will replace tumbling mills in circuits in the not too distant future.
Worldwide the mining industry consumes around 2% of all electrical energy, and comminution is the major consumer, so great efforts are now made to reduce energy consumption, as well as water consumption which is also critical. In some respects we have come full circle- in the 19th century hand sorting was an important technique, and now electronic sorters are proving their worth in crushing circuits, thanks to multi-channel sensors made possible by powerful computers. Sorting will be a major feature in future comminution circuits, scalping out coarse barren rock, and hence reducing energy and water consumption.
I have to say that I wish I were 40 years younger, as our young editors now stand on the cusp of a second industrial revolution, the end of the era of the internal combustion engine, and the dawn of the new era of electric cars (see posting of 30 August). There will be a boom in metal demand, particularly copper, nickel and cobalt, and of course lithium for the Li-ion batteries. We are also now in the age of the "Hi-Tech Metals" used in all computers and smart phones (posting of 5th June), and the increasing demand for metals such as germanium, gallium and indium will put huge pressures on the supply of these metals, many of which are the by-products of base metal processing.  As these metals are present in tiny amounts in each individual computer or phone, and often alloyed with other elements, recycling presents enormous problems, but the move to the circular economy means that we have to get smarter at recovering and reusing the vast quantities that we have already extracted from the earth, rather than relying on continued pursuit of new reserves of ever poorer quality and at substantial environmental cost.
There are exciting times ahead, with enormous challenges, and minerals engineers, and Minerals Engineering, will play a critical role in the dawning of this new age.
Twitter @barrywills

Saturday, 14 October 2017

Recent comments

There have been comments on the following postings since the last update:

Memories of Prof. Keith Atkinson
Golden memories
Seeds of recovery?
CEEC extends its support of MEI Conferences
Will the end of the era of the internal combustion engine herald a golden age for mining?
China demonstrates its strength in numbers
Are these WASET conferences just a scam?
Liberia joins the international band of minerals engineers
Can power be consumed?
In memory of Alan Bromley: an inspirational geologist and a pioneer of geometallurgy

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Wednesday, 11 October 2017

In memory of Alan Bromley: an inspirational geologist and a pioneer of geometallurgy

Only two months ago I reported on the death of Prof. Keith Atkinson, former Director of the Camborne School of Mines, and a geologist with a keen interest in mineral processing (posting of 6th August). Now I report sadly on the death of one of his fellow CSM geologists, Dr. Alan Bromley, who died yesterday at the age of 79.
Alan's career at CSM began in 1969, and he was an inspiration to me during my time at CSM. He was of a rare breed, a geologist, who like Keith Atkinson, had a keen interest in mineral processing. He was one of the pioneers of the then new discipline of process mineralogy, and, although the word had not yet entered the dictionary, one of the early geometallurgists. He was a brilliant teacher, with a zany sense of humour, 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 that 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.
We often reminisced on how process mineralogy has evolved since then, with sophisticated automated scanning electron microscopes now commonplace in large operations. In the early 80s, CSM was the proud owner of one of the early image analysers, the monochromatic Quantimet 720, capable of performing linear scans on mineralogical specimens. Such was the power of this machine, that it lured the late Prof. Peter King from Wits University to a sabbatical at CSM, where he worked closely with Alan on his pioneering research into liberation analysis.
Alan left CSM in 1991 to found Petrolab in Redruth, Cornwall. He sold the business to James Strongman in 2006 and the last time that I saw him was during a visit to Petrolab two years ago to look at the installation of their new Zeiss Mineralogic Mining automated mineralogy system, a machine that Alan and I could never have even dreamt about in the mid 1970s.
Alan (3rd right) at Petrolab in 2015, with James Strongman demonstrating the new Zeiss machine
Alan will be sorely missed and our thoughts are with his wife Lesley, also a geologist, and his two sons from a previous marriage. I would like to invite all of you who knew Alan to share your memories of him below.
Twitter @barrywills

Wednesday, 4 October 2017

Comminution '18: it's not too late to submit an abstract

The official deadline for abstract submission to Comminution '18 was the end of September. We will be preparing the draft timetable towards the end of this month, so there is still time to submit a short abstract if you would like to present your work to an international audience in Cape Town, and have your paper considered for a special comminution issue of Minerals Engineering.
Delegates at Comminution '16
More information can be found in the posting of 21st August, and in the report on Comminution '16.
See what people have said about previous Comminution events.

Monday, 2 October 2017

Liberia joins the international band of minerals engineers

A review of pretreatment of diasporic bauxite ores by flotation separation was submitted to Minerals Engineering in July and was accepted after revision a couple of weeks ago. It is now available on ScienceDirect.
Darius and Borbor
What is so special about this paper is that it is the first to be co-authored by researchers from Liberia, one of the world's poorest countries. Borbor Gibson and Darius Wonyen are in the Department of Geology and Mining Engineering at the University of Liberia, Monrovia. The 3rd author is Saeed Chelgani, an adjunct professor at the University of Michigan, a regular and respected author and reviewer for Minerals Engineering. Three years ago he began work on a USAID project, to teach students at the University of Liberia. He was very impressed with the many bright minds, "brilliant students who could show a high level of understanding scientific matters".
Saeed decided to write an article with them. As there were no mineral processing laboratories he taught them how to write a review article. Flotation is Saeed's main interest and Liberia has bauxite mines so a useful option was a review on diasporic bauxite flotation. He says that he was very impressed by the way they undertook this task and now they are delighted that the article has been accepted and published, the first article co-authored by University of Liberia students.
Congratulations Borbor and Darius, I hope this will motivate you and your colleagues to submit further articles, and thanks Saeed for your dedication in motivating these two students in this way.
Twitter @barrywills