The SAIMM is a professional institute with local and international links aimed at assisting members source information about technological developments in the mining, metallurgical and related sectors.
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A monthly publication devoted to scientific transactions and specialist technical topics is unlikely to be on the priority reading list of the majority of the mining and metallurgical community. But it is the ambition of the Publication's Committee to make the Journal of much wider interest to our general membership from technician trainees to mine managers to CEO's of our constituent companies. It is to entice general readership that some 1200 words of valuable space are devoted to the Journal Comment each month. This is intended to highlight some of the features and impact of the papers to excite and activate attention.

To entice this preliminary glance before confining the publication to the book shelf or even the wpb, the author has to call on a large measure of journalistic licence in style, titles and quotations. It is essential to be spicy, controversial and even provocative to separate it from the abbreviated authoritative but necessary scientific style of the bulk of the contents.
The Journal Comment aims to be an enticement to dig into some important feature of the papers in the issue. For this reason it has been decided to include it as a separate item on the Institutes Web Site. This might provoke those who enjoy twittering, blogging and googling to submit comment and criticism, all of which will be welcomed and responded to. At least it is proof that somebody has read it.
R.E. Robinson

Sustainable development, digitalization, mineral value chains, and new paradigm shifts

The sustainable development of the Earth’s mineral resources ensures the continuous supply of the raw materials and metals upon which we rely. It is a critical global problem, particularly given the growth of emerging economies and increasing environmental concerns. Digitalization and related advances have facilitated important technological progress and the emergence of several paradigm shifts in the mining industry.

One of these shifts is based on the concept of a mining complex or mineral value chain, introduced to reflect an integrated engineering system. This integrated system manages the quality-quantity and extraction of materials from a group of mines, followed by the treatment of the materials through different interconnected processing facilities to generate saleable products for delivery to customers and/or the spot market. Given its integrated nature, a mining complex is optimized simultaneously in a single mathematical model, integrating all its components to capitalize on their synergies, facilitate multi-source data integration, as well as account for and manage technical risks.

Most technical aspects of a mining complex/mineral value chain are substantially affected by uncertainties (stochasticity) stemming from multiple sources. These range from the materials available in the ground to the operational performance of a mining complex, including the ability to adapt to endogenous and exogenous changes. The effects of uncertainty are compounded by multi-level decision-making. This includes decisions about which materials to extract and when, how to stockpile and/or blend materials, use available processing streams, handle waste, manage capital investments, sequence rehabilitation, and how to transport the various products.

Critical sources of uncertainty in this integrated system include the quality and quantity of materials produced from the mines (material supply uncertainty) and the metal’s spot market price (demand uncertainty). With new technological developments, it is possible to quantify and account for these uncertainties, as well as to assimilate new information collected as a mining complex operates, including data from various sensors. This new information needs to be evaluated and used to update models, forecasts, and further support complex, multi-level decision-making.

To date, new geostatistical simulation frameworks and smart(er) simultaneous stochastic optimization approaches allow us to perform the strategic planning of industrial mining complexes under uncertainty at a new scale of intricacy, not imagined a decade ago. As always, new challenges and opportunities emerge, thus it is hoped that the development of new paradigms will extend to stochastic ’self-learning’ mining complexes. Self-learning will capitalize from developments in artificial intelligence, enabling engineering production systems to learn from operations and respond to new, real-time incoming production information collected by a wide range of online sensors, already available in industrial mining complexes.

New digital technologies and related R&D will continue to create technological step-changes and paradigm shifts to advance the performance of mineral value chains and support the sustainable and responsible development of mineral resources – all new, advanced and exciting developments for both the mining industry and academia.

R. Dimitrakopoulos

A selection of diverse papers

The five papers in this edition cover a wide range of topics from computationally effective stope layouts to the bulk chemistry of critical elements in a waste product. The papers have been submitted by authors from South Africa (2), Canada, Kenya and Germany and I have tried to summarize them here.

The paper by Lohmeier, which examines the potential of copper slag from historic smelting operations at Tsumeb as a source of critical elements, describes the project and case study which was supported by the German Federal Ministry of Education and Research.

‘Mineral resources and mineral reserves report readability and textual choice’ by Du Toit and Delport recommends the consideration of adding a plain language requirement to improve the informational value of these reports. An awareness that certain textual choices can affect the interpretation of these reports is highlighted.

The research paper by Kiamba et al. on the prediction of rock fragmentation, presents data collected in a case study from two limestone quarries in Kenya. A particular empirical model was selected and shown to be a valuable instrument for pre surveying the impact of varying certain parameters of a blast plan.

The paper on stope layout optimisation by Sari and Kumral from McGill University, Canada, showed that a cluster based iterative approach generates near optimal stope layouts in a computationally effective manner.

Of particular interest to me was the paper on the evaluation of polymer binders for the briquetting of coal fines by a group from the Centre of Excellence in carbon-based fuels. Northwest University. Potchefstroom. A solution as to how to deal with coal fines has dogged and evaded the coal industry worldwide. This topic has been researched extensively over the past 15 years or so and briquettes of an acceptable physical standard can be produced, albeit at a cost. What has yet to be demonstrated is the economic uses for the briquettes and particularly the combustion products and characteristics.

This selection of papers again highlights the diverse nature of the subject matter that the Journal is pleased to publish. Enjoy the read.

D. Tudor

Communication in the Modern Mine

When asked to pen a commentary for the Journal, I felt it important to address the needs and forms of communication in the modern mine. Such communication, in principle, includes the topics of digitalization and personnel communication – both are vital for mine operational efficiency and for mine health and safety purposes. I will connect the two topics rather than comment individually. Two virtual conferences, namely Digitalization in Mining and the International Mine Health and Safety conference, were held recently. Selected papers from both conferences will be published in the Journal in due course.

Digitalization is all about data and how the data is collected, analysed, and used in decision-making. Traditionally in the past, we have relied on data that is collected manually (by a person with an instrument and a notebook) and which is then entered into some form of spreadsheet, for the compilation of reports. In the case of ventilation, geological, sampling, and geotechnical data, these reports are circulated to the requisite levels in the organization. This is a time-consuming exercise. Good reports may flow quickly, while poor reports tend to reside on desks for a long time.

Other data is used for month-end consolidation and reporting. The result is that information upon which decisions are made is usually out-of-date and historical. This includes critical information related to health and safety.

Similarly, verbal communication between personnel is an equally critical component for effective health and safety. However, this is generally limited in terms of language and the communication medium, thereby leading to communication problems, e.g. between individual mine personnel, including senior staff. Printed communications are equally important for health and safety. In these instances, items such as notices, instructions, and precautionary texts needed to convey information or data are required to address the issues of multilingualism and multimedia communication systems. This also requires the ability to read and write.

Digitalization offers us solutions to these concerns with the opportunity for real-time data collection and transmission through installed monitoring systems and instant transmission to control centres and data analytics. This includes environmental monitoring, survey measurement, production data, fleet management, and geological information.

In the case of geological information, most mining companies have implemented the TARP system, which relies on operators elevating problem situations to higher levels for assistance with solutions. In the case of hazardous geological conditions being encountered, it may take several days to reach resolution. In a digital world, however, the situation can be photographed, digitalized, and transmitted instantly to the point where the right decision can be made. The solution is rapidly communicated back to the operator for action.

Most newer operations have fibre optic systems installed well into the mine, and these need to be fully utilized to enhance communication and real-time control.

Data analytics in the control centre allows decisions to be made in real time and on the fly, through competent people appropriately skilled to make these decisions.

The power of artificial intelligence takes the manual drudgery out of data collection and analysis, making time available for people to reach value-adding decisions and be more in control.

Embracing the world of digitalisation will bring about step changes both in terms of more effective communication and vastly improved mine and health and safety in our journey towards zero harm.

A.S. Macfarlane

New Year, New Horizons

The beginning of a New Year brings with it the hope that new and better opportunities will arise, and this hope is no more acute than in this New Year. The difficulties encountered in all walks of life during 2020 will be long remembered. It remains to be seen how the world fares in 2021.

However, despite all the disruptions of the past year it is gratifying to note growth and continued interest in the SAIMM, its Journal and its published papers. Statistics show that over the year 2020, more than 300 new papers were submitted from 44 countries, with contributions from South Africa (42%), China (12%), Turkey (7%), Iran (6%), India and Indonesia (both 3%), an increasing number from north, central, and other southern African countries, the EU and USA, and from as far afield as Australia to Argentina and Chile to Russia. In terms of website statistics, data indicate that up to 17 000 visitors seek the SAIMM website per month, with the largest overview of pages on publications and Journal papers. As reported by the ASSAf and SciELO SA, over a period of 12 months to July 2020, the Journal recorded 10 349 resolutions for the 1 409 papers, giving and average of 7.4 resolutions per paper.

In the interests of increasing the standard of published scientific papers, new guidelines for authors are currently being drawn up and are due to be published shortly, with new schedules for reviewers to reduce the time for reviewing. The Editorial Board has recently expanded to include the panel of International Editorial Advisors as well as increased representation from industry and academia. As the Journal is now produced exclusively online, this has led to the elimination of printing costs and expanded the potential for circulation to a wider community.

With respect to content, it is worthy to note that the Journal continues to serve the interests of academia and industry, and in so doing it publishes fundamental research and applied industrial papers of interest to both. In addition, the Publication Committee has sought to re-define the Journal’s focus areas, dividing the minerals, mining, and metallurgical (MMM) sectors into further defined disciplines and sub-disciplines, with experienced Editorial Board members dedicated to each sector. In so doing, the disciplines may be seen to cross the entire MMM value chain, i.e., from geological exploration and mineral resources/reserves through mining and metallurgy, to digitalization, the environment, energy, and economics. Some editions provide papers on a dedicated theme, while others present a mix of general papers from a wide range of sources in this multidisciplinary industry.

This current edition of the Journal presents papers that illustrate the multidisciplinary nature of the publication. One paper is on mining (examining the influence of stemming practices on ground vibration on an opencast coal mine), two on extractive metallurgy (one on adapting a crusher design and a second on the effect of froth flotation operational parameters on froth stability and recovery), and a further paper is on energy efficiency (designing a framework to improve current efficiency in electrowinning).

The final contribution illustrates the interdisciplinary aspect of certain papers. For example, the overlap between the mining and geological disciplines. In this case, a pothole stress investigation is reported in the Merensky and UG2 reefs of the Bushveld Complex. The stress measurement in one porthole was found to be unique, indicating a very high stress level in the pothole rock which could have significance from a mining safety point of view. Questions regarding the nature, structure, and mechanical features of the pothole rocks and the geological process responsible for their formation were raised, which require collaboration between the mining and geological communities. It is to be hoped that further such collaboration between these disciplines will ensue. For the present, however, these issues remain unanswered. This paper was published in the interests of safety and not scientific prowess.

With the new steps being taken regarding the operation and content of the Journal and the clearer definitions of its fields of focus, it is to be hoped that such approaches will be of benefit to the entire MMM community and that collaboration, integration, and expansion of technical horizons across the MMM board will increasingly ensue.

R.M.S. Falcon

Journal Comment on December 2020 Edition

Welcome to another edition containing papers of general interest. In this issue, you will find a total of six papers, four of them are mining-related and the rest metallurgy.

This is a typical example of how the Journal intends to maintain a 50/50 split of papers between mining and metallurgy. The topics related to mining include practical modelling of long-term production scheduling, future trends in the international reporting codes, evaluation of mineral resources carrying capacity, and the prediction of flyrock and flyrock-related fields.

Metallurgical papers include a nonlinear prediction model with mass transfer theory and expert rules for refining low-carbon ferrochrome, shock heating of quartz used in silicon and ferrosilicon production, and optimization of chlorite and talc flotation using the experimental design methodology.

It is important to note that the Journal continues to receive papers from the international community, as only two out of the six papers in this edition are from South Africa. This is in line with Journal editor Professor Rosemary Falcon’s observation in May 2020, that approximately 70% of the papers submitted for publication are from international sources. With the Journal’s latest improved impact factor, this trend is expected to continue.

Enjoy the December edition of the Journal!

B. Genc

The Wave

Q.G. ReynoldsDuring the COVID-19 pandemic we’ve heard a lot about waves. First waves passing, second waves arriving, and how many such waves we might still have to endure in the future. Despite all the talk, each wave seems to catch us largely by surprise and we are too frequently left in a shell-shocked state, wondering ‘How on earth could things get so bad so fast?’ The problem here is that epidemics are an exponential growth phenomenon, and human beings are notoriously bad at grasping the import of exponential behaviour. Our internal forecasting and world-modelling instincts like to assume that things change linearly, and as a result we find it difficult to prepare ourselves for the true impact of an exponential event even as our rational minds can see it looming.

Exponential growth is linked to another part of the modern human experience, namely the computing power of our digital machines. This means that their ability to solve any particular problem passes from laughably impossible to difficult, then to trivially easy in a remarkably short space of time, upsetting and revolutionizing everything in its wake – much like a wave.

The point at which that wave breaks over your industry is determined only by how difficult it is to compute solutions to the mathematics describing it. In process metallurgy we might be forgiven for thinking that our engineering challenges are so vastly complex that traditional workflows will never be replaced by computational alternatives, but it’s only a matter of time. Right now the digitalization tsunami is tiny and easily ignored, but the ripples are building momentum, and recent experiences should warn us that it’s time to prepare, prepare, prepare.

Q.G. Reynolds
Pyrometallurgy Division, Mintek
Process Engineering Department, Stellenbosch University

Diamonds: Source-to-Use, 2020

The Diamonds: Source-to-Use 2020 conference was to have been held at the Birchwood Hotel and Conference Centre during 9–11 June 2020. It was to have comprised 1½ days of presentations/exhibitions and two technical site visits, to Multotech and Epiroc, as well as a beer tasting event at Mad Giant Craft Beers. By early March, we had 21 confirmed papers, including two keynote addresses.

And then, just as elsewhere in the world, our plans were interrupted by the hard lockdown associated with the COVID-19 pandemic. Although the SAIMM is well positioned to undertake virtual conferences, it was decided to rather wait until 2021 to hold a face-to-face meeting. Consequently, a new date of 8–10 June 2021 has been proposed. Given the difficulties of travel and the unknowns of how the pandemic will progress, we are looking at the possibility of holding a hybrid event, whereby delegates and presenters alike can either take advantage of a real conference or enjoy the benefits of virtual attendance.

The effects of the global pandemic have been seen across the entire diamond pipeline, disrupting production and sales as well as the entire downstream cutting and polishing industry. With no-one knowing how long these impacts will be with us, and not having certainly on what the post-COVID scene will look like, the theme of the conference – Innovation and Technology – is still appropriate, if not more so. We, as the global diamond community, will certainly have to apply our minds to the changed landscape and come up with new ways of doing business. We expect that the 2021 Diamonds: Source to Use Conference will attract many stimulating papers on the new ‘normal’ within the diamond industry, which may never look the same as it has in the past. We look forward to this new challenge with excitement and more than just a little trepidation.


In order to show our appreciation for the effort that many of the presenters dad made to get their papers completed and peer-reviewed in time for the original conference, it was decided to give them the opportunity to publish in this edition of the SAIMM Journal. The papers in this volume highlight some of the advances made across the range of exploration, mineral processing evaluation, and reporting of diamond projects.

T.R. Marshall

Meeting industry challenges

As we find ourselves in a world dominated by COVID-19, it is clear that the mining industry is not exempted from the impact of the pandemic. The industry will change in ways we cannot yet quite appreciate. This comes on top of the other challenges that mining (and indeed the wider world) is faced with, such as climate change, uncertain trade relations, and the imperatives of sustainable development. The coal mining industry faces a further challenge in that the need to reduce carbon emissions will inevitably lead to a reduction in the use of coal, particularly for the generation of power. It is accepted that the transition to renewable energy will proceed, and that the use of coal will decline in the medium to long term. A transition is needed that will result in security and affordability of electricity supply, while at the same time allowing the industry and all its stakeholders to adjust to the disruptions that such a transition will cause. For this to happen, stakeholders need to find new and innovative ways to operate, and the input of the scientific community is a crucial part of this process. In this edition of the Journal, general papers are published. Some touch directly on the issues the coal industry faces; others more indirectly. All, in their own way, will assist in meeting the challenges the mining industry is faced with.

H. Lodewijks
Coaltech Research Association NPC

Empowering the African minerals industry through diversity and inclusion

Many organizations that launch diversity and inclusion initiatives cite research showing that companies with more diverse teams outperform those with a more homogeneous workforce. According to some of these reports, the inclusion of voices from different geographic, gender, economic, and cultural groups not only creates opportunities for individuals to grow within the company, but also helps the organization to harness the talent and potential for itself, leading to greater profitability and value creation. Therefore, looking at it in simple terms, there is value in embracing diversity and inclusion initiatives in the workforce.

The Southern African mining sector, just like the global mining industry, still faces huge challenges when it comes to gender inclusivity and the creation of a supportive environment for career advancement of not only women but also other workers from diverse backgrounds such as, for example, LGBTQI. Issues such as gender disparity, safe spaces in the workplace, protective equipment, sanitation facilities, pregnancy and child care are but a few challenges that continue to plague the sector. There is thus a great need for strategies for advancing womens’ representation and encouraging decisions that are in the best interests of a diverse workforce in the mining industry.

In most cases, diversity and inclusion are often treated as a single initiative owned exclusively by the human resources section of each organization. However, for real change to happen, leaders of the mining industry need to not only buy into these initiatives, but also embrace the value of belonging. It is only when this happens that we will witness a significant change in the mining landscape. The industry must also realize that sticking to quotas does not mean inclusion; it’s only compliance and not commitment. The industry needs to go beyond that. Identifying individuals, creating safe spaces for them, providing support for them to grow into their roles, and creating conditions that promote inclusion on a daily basis will ensure that such initiatives are not once-off, but are long term, which would be of more benefit to mining companies.

The SAIMM as a professional organization that represents the needs and interest of mining professionals in southern Africa also has a role to play in driving such an agenda. And as such, the Diversity and Inclusion in the Minerals Industry (DIMI) Committee was initiated to raise awareness on these issues and to create platforms for discussion that can lead to the development of strategies for advancing and encouraging decisions that are in the best interest of a diverse workforce. The Committee is made up of dynamic male and female, emerging and experienced professionals from both industry and academia, who are all passionate about seeing positive changes in the minerals sector.

The Committee has held a number of talks at local universities to raise awareness among students and sensitize them particularly to issues related to gender inclusivity and safe spaces within the mining industry. The Committee has also hosted a workshop focusing on challenges and strategies for mentoring and retaining women in the mining industry. A webinar series given by highly notable speakers from within and outside the industry is scheduled for the month of August 2020, to celebrate Women’s Month. The series will cover talks on a weekly basis touching on diverse issues such as gender inclusivity in the workplace, creating a positive environment for diversity, conquering inner fears, developing a growth mind-set, and workplace strategies for mental health. The Committee is also planning to host the first-ever SAIMM conference on diversity and inclusion in the mining industry in August 2021.

The Committee has also been looking at establishing collaborations with partners who are keen to enhance the diversity landscape and cause in the mining industry. Informal collaborative partnerships have been established with the Minerals Council South Africa and Women in Mining South Africa (WIMSA). It is expected that all these strategies and activities will go a long way in catalysing a positive change in the mining industry.

S. Ndlovu
DIMI Chairperson

Focus on the Student Edition

‘It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us …’ – the opening lines to A Tale of Two Cities (1859) by Charles Dickens. And I say Amen to that!

Those words written 161 years ago resonate across nations as we struggle against the COVID-19 pandemic and a ravaged world economy. Gold and palladium at record levels – coal and zinc bottoming. Lives or livelihoods – I would not like to be the decision-maker having to choose between these options in South Africa with 14 mineworkers having died from COVID-19, and with nearly 3000 cases within the sector having been recorded at the time of writing. It is apparent that the balance, even in the world’s wealthiest countries, has tipped in favour of livelihoods over lives.

My heart says that this decision is insensitive to the pain of families who have lost a cherished parent or grandparent, or have to confront the anguish of entering the workplace and worrying about the risk of infection, but my brain says the alternative is no better. Without going back to work and earning money to buy food, many will face the spectre of malnutrition affecting the youngest and weakest within their families. A similar dilemma is facing us regarding the reopening of schools and universities. Opening will spread the virus, but remaining closed will produce a generation of deprived students who will struggle to catch up – probably for the rest of their lives. Hoping that home schooling or online learning are viable alternatives ignores the fact that these options are really open only to families with well-educated parents and/or with the financial means to purchase electricity, computers, and bandwidth, and will inevitably perpetuate and grow existing inequalities in our society.

This copy of the Journal is the Student Edition, containing the research output of students completing their final year of their chosen engineering course at local universities in both mining and metallurgical disciplines. Of the seven papers, three are on mining topics, and four on metallurgical topics, and there is no common theme among the papers. As members of the SAIMM, we can take some pleasure in reading the student papers in this copy of the Journal and feeling that the human resource capability required to sustain the mining industry is already in the making. I therefore encourage you to read the papers, or at least the abstracts, to get some feel for the research currently being undertaken at our universities. The research, though published in this copy of the Journal, was completed last year. Given the pandemic and its impact on the student body, I can only hope that we have sufficient papers this time next year to continue the tradition of issuing a Student Edition!

Five of the papers originate from the universities of Johannesburg, Pretoria, and the Witwatersrand, one from North West, and one from Stellenbosch. I don’t place any significance on this finding, as the distribution tends to vary significantly from year to year, depending upon the student body in that year and the selections made on where to publish their papers. I mention this only because I studied at the University of Natal, Durban (now the University of KZN), and I was hoping to see a paper from my alma mater. In my student years, the late 1960s and early 1970s, the departments of Chemistry and Chemical Engineering were positioned side-by-side, and were the last buildings on the south side of the campus before descending to Logan’s bookshop.

The Department of Chemistry, where I studied and graduated with my PhD, has since relocated to the Westville campus. The first-year chemistry course, and a small part of the second-year course, was shared by both departments, so I had many friends in engineering. Most left after 4 years, but I continued my loose association with engineering as I became a laboratory demonstrator for the first- and second-year engineering students in the chemical laboratories. I have since met many of those students who remembered the generally disliked three-hour laboratory afternoons, and recalled that I was intimidating as I stalked the benches looking over their shoulders at their mostly inept attempts to master practical chemistry. Really, me? – Never, you must be confusing me with someone else!!

The Department of Chemical Engineering was dominated at that time by two giants of South African academia and metallurgy: Professor Peter King and Professor Ted Woodburn. I knew of them by reputation only at that time, but I had the pleasure of meeting them later on many occasions in ‘real life’. I would like to quote an extract written by Professor Mike Moys of Wits (but a postgraduate student at Durban around that time): ‘They supported and competed intensely. Allow me to reminisce briefly about Ted. Ted would arrive in the morning in his Mini Minor. Those of you who knew Ted – a very large man – can imagine Ted extricating himself from the Mini! Ted’s other idiosyncrasy was his habit of management by walking around chewing his tie. Ted also had a remarkable laugh which defies description and echoed through the building every now and then. Peter kept his cool!’

Memories linger, and some seem to become more vivid with the passage of time. As Dickens wrote: ‘It was the best of times ...’, or that was what I recall from my student days. Does anyone else remember those days in Durban, or am I alone with these memories? Is it not human nature that our youth was always the best of times? But will this still apply to today’s students growing up in the midst of the COVID-19 pandemic? Perhaps to them, in years from now, looking back, ‘it was the worst of times’. I hope not!

R.L. Paul