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By R. T. Jones

"SynopsisScientific progress relies on the publication of ideas and experimental results that can be replicated, tested, and improved over time. The first printed book on metallurgy to have been published in Europe is considered to be De la Pirotechnia, written in Italian by Vannoccio Biringuccio, and published in Venice in 1540. Together with De Re Metallica, written by Georgius Agricola and published in Latin in 1556, this can be considered to mark the start of scientific and technical literature in this field. Scientific publishing of journal papers has been in existence for 350 years, since the world's oldest and longest-running scientific journal, the Philosophical Transactions of the Royal Society, was first published in London in 1665.The nature of scientific societies has changed significantly since the early days when regular meetings were held to discuss science and conduct experiments, and the reading of scientific papers took place, and publication of papers was undertaken to record the proceedings of meetings, often including rather robust debate. In today’s world, there is a plethora of publications, and it is close to impossible for anyone to keep up with the vast flow of information. International conferences with hundreds of presentations have taken the place of the local meetings that used to discuss a single paper or experiment. In this frenetic environment, it is essential that researchers are able to trust the material they read.The system of peer review is used to maintain standards and to improve the quality of papers. This vital system is, however, significantly flawed. There is little incentive for reviewers to invest sufficient time in picking up all errors in publications, and any ineptitude on their part is usually protected by anonymity. It has reached the point where some reviewers have mistakenly permitted the publication of hoax papers deliberately presented with a complicated scientific facade. In light of such astounding inadequacies, perhaps a more open review process would be an improvement. Electronic publishing allows errata to be linked to the original papers.There is an increasing trend towards open access for papers in scientific journals and conference proceedings, which helps to reach as wide an audience as possible. This also supports the statement in the Universal Declaration of Human Rights, which says ‘everyone has the right freely to … share in scientific advancement and its benefits’."

Jan 1, 2015

By H. E. James

Much has been said and written about the need to reduce South Africa's dependence on gold. To compensate for the decline in the country's foreign-exchange earnings resulting from the phasing out of gold, which must inevitably occur at some future date, a far higher priority will have to be placed on the mining, beneficiation, and export of the 59 other mineral commodities produced in South Africa. The basic strategy of the mining and metallurgical industries should be to move from the traditional approach of establishing a resource base to the establishment of a market base; to turn from production orientation to market orientation; and to rely less on exploration and economies of scale and more on process innovation and product development. The enthusiasm, entrepreneurial spirit, and commitment of the leaders in the mining and metallurgical industry will clearly be of decisive importance in the establishment of new industries for the beneficiation and export of added-value mineral-based products. The State can make a significant contribution by the provision of a welldeveloped and efficient infrastructure, including rail and harbour facilities, communications and health services, roads, and of electricity and water supplies. In our search for a new development strategy for the beneficiation and export of South Africa's minerals, we need to recognize that no one nation has all the mineralresources that it needs. Commercial and strategic manipulation of mineral supplies should no longer be tolerated. The future of the human species lies in international cooperation and in a greater understanding of the limitations of the world we live in.

Jan 1, 1985

By C. E. Fivaz

SYNOPSIS Tribute is paid to J.S. MacArthur and the Forrest brothers for their invention. The opinion is expressed that the successful application of their process, not only saved the gold-mining industry on the Witwatersrand from stag¬nation for an indefinite but probably prolonged period, but also made a major contribution to the economic growth of the country in the twentieth century. A background is given of the activities of prominent chemists who researched the solubility of gold in cyanide solution prior to the MacArthur-Forrest invention. An account is given of the invention and patenting of the cyanidation process, and of the golden rule that the patentees laid down for themselves, which came close to wrecking the invention. The South African gold-mining scene from the discovery of gold on the Witwatersrand in 1886 up to 1890 is sketched. An account is given of how, when unoxidized ores were first encountered, the recovery efficiency dropped alarmingly, gold shares were sold on an unprecedented scale, and doom and despondency seized the town of Johannesburg. The complete turnabout in the fortunes of the South African gold-mining industry after the introduction of the cyanidation process in 1890, the steady rate of increase in production after the Anglo-Boer War, and its effect on the South African economy are described. A brief look is taken at the effect of gold mining on secondary industry. The deportment of the gold that is not dissolved from the ore by the cyanidation process is illustrated. Some thoughts are expressed on what can be done to increase the gold recovered by cyanidation.

Jan 1, 1988

By D. F. Malan

This paper provides an overview of the concepts of citations and journal impact factors, and the implications of these metrics for the Journal of the Southern African Institute of Mining and Metallurgy (JSAIMM). Two key research literature databases publish journal impact factors; namely, Web of Science and Scopus. Different equations are used to calculate journal impact factors and care should be exercised when comparing different journals. The JSAIMM has a low impact factor compared with some of the more prestigious journals. It nevertheless compares well with journals serving other mining sectors, such as the Canadian CIM Journal. The problems associated with journal impact factors are discussed. These include questionable editorial practices, the negative impact of this concept on good research, and the problem of a few highly cited papers distorting the journal impact factor. As a consequence, there is growing resistance to the use of journal impact factors to measure research excellence. The San Francisco Declaration on Research Assessment is a global movement striving for an alternative assessment of research quality. As a recommendation, the Editorial Board of the JSAIMM should adopt a pragmatic approach and not alter good journal policies simply to increase the journal impact factor. The focus should remain on publishing excellent quality papers. Marketing of the Journal, the quality of the published papers, and its open access policy should be used to counter the perception that journals with high impact factors are better options in which to publish good research material.

Sep 1, 2022

By A. Rejeb, A. Millard

ABSTRACT: An evaluation of the importance of the thermo-hydro-mechanical couplings (THM) on the performance assessment of a deep underground storage design has been made as part of the international DECOVALEX III project. It is a numerical study that simulates a generic repository configuration in the near field in a granite medium. The thermo-hydro-mechanical evolution of the whole configuration is simulated over a period of 100 years. The model used to represent the unsaturated behaviour of the various porous media makes allowance for moisture transfers through the effect of thermal and water gradients. The paper presents a comparison of the temperature, water pressure and stress fields obtained by TM, TH, HM and THM coupled calculations. The results demonstrate that temperature is hardly affected by the couplings. In contrast the influence of the couplings on the mechanical stresses is considerable. This is attributed to the key role that water has on bentonite swelling or shrinkage effects that are dependent on its saturation level variations. KEY WORDS: Modelling, thermo-hydro-mechanical couplings, temperature, pressure, stress. ZUSAMMENFASSUNG : Im Rahmen des internationalen Projekts DECOVALEX III wurde untersucht, wie groß der Einfluss thermisch-hydraulisch-mechanischer Kopplungen (THM) auf die Leistungsfähigkeit eines Konzeptes zur Lagerung hoch radioaktiver Abfälle zu bewerten ist. Bei dieser numerischen Behandlung wird eine generelle Lagerungskonfiguration in granitartigem Milieu simuliert. Die thermisch-hydraulisch-mechanischen Prozesse werden für eine Dauer von 100 Jahren simuliert. Bei dem Modell, mit dem das Verhalten der verschiedenen, unterschiedlich porösen Milieus in ungesättigtem Zustand dargestellt werden soll, werden die Feuchtigkeitstransporte infolge thermischer und hydraulischer Vorgänge berücksichtigt. Verglichen werden in diesem Artikel verschiedene Temperatur-, Wasserdruck- und Beanspruchungsfelder, die sich aus TM-, TH-, HM- und THM gekoppelten Berechnungen ergaben. Dabei stellte sich heraus, dass die Temperatur nur gering von den Kopplungen berührt wird. Die Einflüsse der Kopplungen auf die Mechanik sind hingegen bedeutend; ausschlaggebend dafür ist der Faktor Wasser, der den Bentonit je nach Sättigungsgrad quellen oder trocknen lässt. SCHLÜSSELWÖRTER: Modellbildung, thermisch-hydraulisch-mechanische Kopplungen, Temperatur, Druck, Beanspruchung. RESUME : Dans le cadre du projet international DECOVALEX III, une évaluation de l’importance des couplages thermo-hydro-mécaniques (THM) sur les performances d’un concept de stockage de déchets fortement radioactifs a été menée. Il s’agit d’une étude numérique simulant une configuration générique de stockage en champ proche dans un milieu granitique. L’évolution thermo-hydro-mécanique de l’ensemble est simulée sur une période de 100 ans. Le modèle utilisé pour représenter le comportement non saturé des différents milieux poreux prend en compte les transferts d’humidité sous l’effet de gradients thermiques et hydriques. L'article présente une comparaison des champs de température, de pression d’eau et de contraintes obtenues par des calculs couplés TM, TH, HM et THM. Les résultats montrent que la température est peu affectée par les couplages. En revanche, l’incidence des couplages sur la mécanique est importante; ce qui est attribué au rôle majeur joué par l’eau à travers les effets de gonflement ou de retrait de la bentonite selon la variation de son degré de saturation. MOTS-CLEFS : modélisation, couplages thermo-hydro-mécanique, température, pression, contrainte.

Jan 1, 2003

By D. B. Paterson

In view of decreasing head grades, the relatively high gold price, and recent developments in metal evaluation, an exercise was initiated to determine the extent of gold concentration, the mode of occurrence, and the areas of concentration within the run-of-mine milling circuits of Randfontein Estates Gold Mining Company (Witwatersrand) Limited. The total gold content of three of the thirteen run-of-mine mils in the Group was measured as a typical lock-up of approximately 200 kg per mil. The majority of this gold was concentrated either behind the grid-type body liners or within the pockets of the body liners. This paper is an account of the experimental procedure and the results obtained, and highlights possible means of limiting gold lock-up in future.

Jan 1, 1988

By B. G. Russell

A wide range of minerals is found within the Republic of South Africa, many of which are exploited to a greater extent than in similar deposits found elsewhere. It is often asked whether this is atributed to the high grade of the ores encountered in this country, or whether such factors as fiscal and Infrastructural incentives create an economic climate that has en bled the mining industry to successfully extract and market minerals at a profit. This paper views South Africa's mineral resources in a regional and global context In an attempt to place the country's geological wealth in perspective. It represents the author's own Views, and not necessarily those of the Department of Mine al and Energy Affairs.

Jan 1, 1986

By J. M. Benson

Metal powder compaction offers unique advantages in the manufacture of net-shape components using techniques such as laser sintering, conventional press and sintering, metal injection moulding, direct rolling, direct forging, and hot isostatic pressing. If the output from the primary metal production process is in powder form, then considerable cost and energy savings can be realized by direct conversion to semi-finished or final shapes. This possibility exists for titanium and possibly also for Ta, Zr, Hf, and Nb metals. However, these attractive benefits are associated with some significant risks. The high surface-to-volume ratio of powder particles coupled with the reactive nature of these metals means that special care must be taken when handling them. Powder explosions are unfortunately still a regular occurrence internationally and these often result in serious injury and loss of life. Even seemingly 'safe' compounds such as sugar, flour, and grain can be extremely hazardous when handled or milled and dust clouds are produced. In addition, exposure to airborne particles can have adverse effects on the human body, especially when particles are inhaled on a regular basis. Furthermore, the medical consequences of these are not fully understood, especially in the case of nanoparticles. The impact is often not observed immediately and debilitating illnesses may emerge only years or decades later. As far as is known, there are no South African guidelines for handling of metal powders. This paper attempts to provide an awareness of the risks associated with metal powders (including those produced indirectly by other metalworking/finishing operations) as well as some guidelines for their safe handling, based on international best practices.

Jan 1, 2012

By T. R. Curr, W. A. Gericke, J. Basson

South Africa is a leading player in the international ferro alloys industry. Historical factors that have contributed to this dominant position include an abundance of natural resources and relatively low cost electricity. A number of relatively recent developments are potentially threatening this position. These include new legislation affecting the mining and minerals industry, a shortage of some types of suitable reductants, depletion of surplus electricity generation capacity with resultant threat of real escalation of electricity prices and pressure resulting from the recent strengthening of the South African Rand. The industry is addressing these challenges in a number of ways to ensure long-term viability. Some of these measures include investments in more efficient technologies that have economy of scale benefits and are less dependent on expensive reductants and electricity. Local macro-economic impacts include new legislation regarding ownership of enter-prises, mineral rights and royalties on mineral sales, development plans for port and rail infrastructure, as well as initiatives to expand electricity generation and coke production capacity. The fundamentals for being a successful ferro alloy producer are still largely in place for South African producers. Therefore the South African ferro alloy industry will remain competitive and is well placed for continued growth in line with the international growth in ferro alloy demand. The industry should emerge leaner, more efficient and ready to respond to any future demands of the industry. This paper will cover the present status of the industry, the factors that are impacting thereon and a view on its future outlook.

Jan 1, 2007

By S. Mudau, P. Mohasoa, M. J. Cole

Derelict and ownerless (D&O) mines in South Africa have been an ongoing concern for over a decade. While some progress has been made to rehabilitate D&O asbestos sites, significant work remains, exacerbated by the growth in illegal mining. There are concerns regarding the accuracy and transparency of the D&O database, lack of oversight, and constrained funding, and the government is increasingly looking to the private sector to fund rehabilitation. Given these challenges, a new, sustainable approach to D&O sites in South Africa is needed to bring clarity and transparency to the process, recognise responsibilities and promote partnerships, and explore economic opportunities at D&O sites to reduce the financial liability and respond to the growing demand for critical minerals. This article has three components: i) reviews of international D&O good practices; ii) it analyses South Africa’s current approach and the D&O sites; and iii) proposes a D&O framework that addresses data, risk ratings, responsibilities and rehabilitation, economic opportunities, and stakeholder engagement. The study finds that the majority of the 6,100 so-called abandoned D&O mines are quarries and mine site features, 16% are operational, at least 11% have owners, and only 752 (12%) require rehabilitation. The framework aims to bring clarity and fairness to decision-making and to assign risk and responsibility for rehabilitation and seeks to incorporate economic opportunities to reduce the financial burden of rehabilitation, create jobs for local communities, and respond to the growing demand for critical minerals for the clean energy transition.

Apr 25, 2025

By A. Sokolov, M. Demsky, E. Hasikova, V. Gostilo

"Previously, we upgraded and implemented two gamma activation assay (GAA) systems designed to analyse the gold content in raw ores at Zarafshan laboratory, Uzbekistan, and achieved a detection limit of less than 0.05 g/t under actual industrial conditions. Having started to design a fully modern, industrial GAA system for mining companies, this paper analyses the advantages, disadvantages, and special features of all major system components that can influence the sensitivity and accuracy of the analysis. The results of a study to optimize the detector geometry and sample size are presented and the performances of the linear electron accelerator, detector array, and sample transportation system of a modern, industrial GAA system for analysing gold, silver, and rare earth elements are considered. IntroductionGamma activation analysis (GAA) has considerable potential as a future replacement for traditional fire assay analysis in gold mining (Hoffman, Clark, and Yeager, 1998; Morse, 1977; Bourmistenko, 1986, 1981; Sammut, 2016; Tickner et al., 2017). The essence of GAA is to irradiate ore samples with high-energy gamma quanta generated by an electron linear accelerator (LINAC) and then to use a gamma spectrometer to detect the induced activity of the excited gold nuclei. The advantages of this method are discussed in detail elsewhere (Hoffman, Clark, and Yeager, 1998; Morse, 1977; Bourmistenko, 1986, 1981; Sammut, 2016; Tickner et al., 2017), where it is shown that GAA is uniquely suited to analysing ore samples when mining for gold, other precious metals, and accompanying elements.These advantages were realized in three industrial GAA laboratories that were commissioned in Zarafshan, Uzbekistan in 1977, in Magadan, Russia in 1979, and in Batagay, Russia in 1986 (Bourmistenko, 1986; Nii Tekhnicheskoy Fiziki I Avtomatiki, n.d). In 1989, a fourth industrial GAA laboratory was commissioned at a gold mine in Tommot, Russia. However, the project was subsequently halted due to economic reasons (Moshkov and Tjamisov, 2017). Currently, only the laboratory of the Muruntau mine in Zarafshan, Uzbekistan is in operation. The gamma activation method for gold determination is widely applicable at this mine owing to its high productivity and low cost of analysis. An outstanding aspect is the performance of more than one million analyses per year."

May 1, 2019

By A. Kapito

The ferrite-pearlite microstructure is the most popular microstructure for alloys used in structural applications, including railway wagon wheels. These alloys have been designed through alloying and thermo-mechanical processing to have a refined microstructure. Ferrite-pearlite alloys are low cost, weldable, have good fabricability, and are reliable under extreme conditions. Given these performance attributes, it seems unlikely then that their dominant position as structural steels would ever be challenged by alternative microstructures. One major achievement in the development of ferrite-pearlite steels has been in the refinement of their interlamellar spacing to very fine distances of the order of < 0.3 um. A refined microstructure increases the hardness of the alloy, thus increasing its life under wear conditions. The interlamellar spacing in pearlitic steels has, however, been refined almost to its theoretical limit. The increasing demand for speed and increased axle loading on railway wagons requires the use of stronger, tougher, and more durable materials. This has opened the window for the development of novel bainitic steels. Bainitic alloys have a higher level of microstructural refinement than pearlitic ones. They have shown to have good wear resistance and rolling-contact fatigue resistance, and high toughness. This paper will discuss the progress to date on the development of bainitic railway wheel alloys. Four alloy chemistries have been chosen for possible further development.

Jan 1, 2012

By B. C. Alberts

Planning the use of South Africa&apos;s energy resources, especially coal, is of the utmost importance. The State and the mining industry require reliable official estimates of the economically mineable coal reserves for planning purposes. An overview of al the previous reserve estimates is given, with specific attention to the two most recent estimates-those of Petrick and De Jager. The differences between these two estimates are highlighted. The following important aspects are discussed: . the need to update the information regarding South Africa&apos;s mineable coal reserves, . the necessity of understanding and agreement between the coal-mining industry and the State department responsible for updating the coal-reserve data, and . the importance of the specific assumptions used in the updating of the data. A downward adjustment of mineable reserve figures is proposed, and the factors that influence the meaningful exploitation of the coal reserves are discussed. A recommendation is made as to how the Waterberg coal reserve should be exploited, and it is concluded that the Soutpansberg Coalfield cannot be exploited economically in the foreseeable future. An evaluation of the status of the coal-export trade is made and compared with the assumptions and targets set at the start of the coal-exportation scheme. The comparison shows the extent to which the exploitation of the coal reserves is being negatively influenced by the current market situation. Recommendations are made regarding planning for the coal-export market, and the aspects that have to be taken into account to keep South Africa in the export market are identified. Reference is made to the fact that the present unrestrained wage and salary adjustments, which show a total disregard of South Africa&apos;s poor productivity record, require serious thought and speedy rectification if the country is to survive in the export market. A salary and wage strategy must be developed to suit the specific needs of the Republic of South Africa.

Jan 1, 1987

By R. C. M. Minnitt, W. Dr. Assibey-Bonsu, F. A. Camisani-Calzolari

Born in Bothaville (OFS) on the 26th August 1919, Daniel G. Krige grew up in Krugersdorp on the West Rand. Hematriculated from Monument High School in Krugersdorpin 1934 at the age of 15 and graduated with a B.Sc. (Eng.)degree in mining engineering from the University of the Witwatersrand at the end of 1938 (age 19). In 1938 he joined Anglo Transvaal where he worked on a number of gold mines until 1943, gaining a wide range of valuable practical experience in surveying, sampling and ore valuation. He then joined the Government Mining Engineer’s Department where he worked for 8 years during which time he participated in the uranium negotiations with the British and American authorities and designed the uranium pricing formula for the contracts which led to the establishment of South Africa&apos;s profitable uranium industry in the early 1950s. During the same period he began his pioneering work in the application of mathematical statistics to the valuation of new gold mines using a limited number of boreholes and of ore reserves for existing mines. His early papers in the application of mathematical statistics, some republished in French, created world-wide interest that led to the development of the science and concepts that surround the spatial evaluation of mineral resources and reserves known as geostatistics. This technique has contributed to improved ore evaluation techniques as well as the reduction of the financial risks associated with investment in mining enterprises. Furthermore, it led to the recognition of his contributions to the evaluations of mineral deposits through the coining of the term ‘kriging’ that is used to describe a spatial mineral evaluation process known and practised in international mining circles. He continued his work in geostatistics throughout his career as Group Financial Engineer of the Anglovaal Group until his retirement in1981 and afterwards for ten years as Professor of Mineral Economics at the Witwatersrand University. He is still active as a consultant and is a registered Professional Engineer. He has published some 90 technical papers both locally and overseas, some in Russia, and has lectured and participated in international congresses in many countries. His contributions were recognized by the Witwatersrand University through the award of the D.Sc. (Eng.) degree in1963, by three honorary degrees (from the universities of Pretoria, UNISA and Moscow State Mining University), by many awards from the South African Institute of Mining and Metallurgy, the International Association for Mathematical Geology, Die Suid Afrikaanse Akademie vir Wetenskap en Kuns, the SME of the American Institute of Mining Engineers, the International APCOM Council in1999, the University of Antofagasta in Chile, and by the South African President (Order for Meritorious Service, Class 1, Gold). He has served on various Government committees, notably that for State Aid for gold mines (1967/8) and designed the State Aid formula which enabled many mines to survive a period of low gold prices; also various taxation committees, and the mining mission to Iran in 1974. He is a fellow and/or honorary life member of various technical societies locally and overseas, including the Royal Society of South Africa. During the period in the Government service he also handled several of the post-war lease applications in the Free State and Klerksdorp goldfields. The fact that decisions on new gold mines of critical importance to the State and the economy as a whole, were being taken on a limited number of drillholes without any scientific analysis of the risks of failure, stimulated him to start basic research into ore evaluation. His approach was based on the application of Mathematical Statistics to these problems, an approach of which very little was known world-wide at that stage but which had already been initiated in South Africa by Sichel via the lognormal frequency distribution model. In Krige&apos;s 1951 paper published in the Journal of the Chemical, Metallurgical and Mining Society of South Africa he covered the statistical explanation of the conditional biases in ore block valuations and stimulated the use by several gold mines of regression corrections for routine ore reserve valuations, a technique which, in effect, was the first use on an elementary basis of what is now known as kriging. His 1952 paper introduced, inter alia the basic geostatistical concepts of ‘support’, ‘spatial structure’,’ selective mining units’ and ‘grade-tonnage curves’. His 1951 paper was based on his M.Sc. (Eng.) thesis submitted in the Department of Mining Engineering to the University of the Witwatersrand, and expounded his pioneering work in geostatistics in more detail. His early research papers that had stimulated interest in several mining circles overseas, were republished in French in1955, resulting in a major research effort by French mining engineers in this field. This, in turn, led to the establishment of the now world-renowned French school of ore evaluation in Fontainebleau, Le Centre de Geostatistique de l’École des Mines de Paris. As the Group’s Financial Engineer at the Anglovaal Head Office until his retirement in 1981, he was responsible for

Jan 1, 2003

By M. Hopf, E. Rossouw

Keywords: Pyrometallurgy, furnace, copper coolers, freeze lining, monitoring, Saveway The use of water-cooled copper components as sidewall elements of submerged arc furnaces and other pyrometallurgical applications has become increasingly common. The high cooling efficiency of copper has made it possible to increase the service life of furnace refractories when compared to conventional refractory linings. However even the self-healing effect of ?freezing? worn areas of the lining does not necessarily protect the copper coolers against wear or corrosion completely. In order to avoid furnace explosions, various methods have been used to monitor the wear of coolers. Unfortunately, these have not been able to consistently identify localized wear. Thos Begbie (South African) and SAVEWAY (German) jointly developed technology to embed a line sensor into the copper cooler during the casting process. This system allows an exhaustive monitoring of the copper cooler. A SAVELINE sensor is placed inside the copper-cooling panel between the water-cooling passage and the hot face of the panel. The sensor follows the meandering shape of the cooling water channels. In the first instance, the sensor provides analogue information as the thickness of the copper reduces. Secondly, this wear signal will be confirmed by a signal of interruption if the sensor is washed away. Because of the structure of the sensor, a self-diagnosis is possible and indications can be confirmed (double proofed). Subsequent to the manufacture of some test pieces, coolers for a large submerged arc furnace were manufactured. The sensorized coolers have been installed at the intermittent surface (slag line) where the largest amount of corrosion has been encountered. The system has been operating since December 2005 in what is considered one of the largest submerged arc furnaces in South Africa.

Jan 1, 2006

By R. T. Jones

Technical publications in the field of mining and metallurgy have existed for a long time. Recent developments in electronic publishing on websites make it possible to disseminate information more widely and cost-effectively than before. Professional societies have an opportunity to serve their members and their industry by publishing high-quality peer-reviewed papers on their websites as well as in printed form. Older publications can be scanned, and optical character recognition used to provide searchable text. Various business models exist around this process. This paper outlines the approach used by the Southern African Institute of Mining and Metallurgy (SAIMM) to provide free open access to their journal papers and conference proceedings, as well as the work being done by OneMine.org to collect technical papers from a number of international societies and make them available to subscribers via a large database. An approach is outlined that should be of benefit to authors, readers, and society at large.

Jan 1, 2012

By J. H. Rhee, H. B. Ku, J. S. Lee, H. J. Park, B. S. Jang

A large wedge failure had occurred in the study area which was under construction. Therefore, in order to analyze the potential instability for this rock slope, the authors conducted numerical analysis with DEM and then the behaviour of rock mass was analysed after appropriate reinforce-ments were applied. Ein großer Keildefekt geschah in dem Untersuchungsgebiet, das im Bau befindlich ist. Deshalb, um die potentielle Unbeständigkeit für diesen Felsenabhang zu analysieren, führen die Urheber zahlenmäßige Analyse mit DEM. Und dann wird die Bewegung der Felsenmasse ana-lysiert, nachdem angemessene Verstärkungstruppen angewandt werden. Un grand échec de coin sèst passé dans le région étudié qui était en construction. Par conséquent afin d’analyser linstabilité potentielle de cette pente de roches, les auteurs ont mené une analyse numérique avec DEM. Ensuite le comportement de la masse de roches pourrait être analysée après les renforts appropriés étaient appliqués.

Jan 1, 2003

By N. Duda, W. Koperska, S. Anufriiev, P. Stefaniak

In mineral processing plants ore extracted from mines is processed to obtain a concentrate with the highest possible concentration of this valuable product. It is a complicated multi-stage process. Usually, the first step is sieving the ore, which is typically done using vibrating mining screens. There is often only a limited number of these machines in the technological chain, which is why their continuous operation, and proper maintenance is crucial for the whole process. Predictive maintenance is the best strategy in this case because it allows for minimising the number and duration of unexpected stoppages. It consists of the prediction of future failures based on available real-time data, and predictive models built upon this data using, for example, machine learning techniques. In this paper we concentrate on feature generation for future predictive maintenance model development for a vibrating screen, based on an example of a KGHM ore processing facility in Polkowice-Sieroszowice. We focus on two types of measurements: bearings temperature and vibrational data. Based on the raw data, the process of more advanced feature engineering is described. By transforming the temperature data we calculate characteristics of bearing cooling and heating dynamics, while based on vibrational data, the aggregated characteristics of the vibrations are derived. Such features are calculated on a long-term basis, and then they are compared to the data related to vibrating screen maintenance to estimate their significance for the prediction of particular failures of the machine.

Sep 1, 2021

By K. G. Philo, R. C. W. Webber-Youngman

mining, where data-driven decision making optimizes resource extraction, enhances safety, and ensures sustainability. The adoption of digital technologies like artificial intelligence (AI) and the Internet of Things has amplified the importance of digital information. However, the integrity and security of this information are paramount, leading to the exploration of blockchain technology as a potential solution for secure digital value exchange in mining. This research examines blockchain's capabilities, drawing insights from its applications in sectors like banking, government, healthcare, and entertainment, and evaluates their relevance to mining's core value chain processes. The study identifies blockchain's distributed ledger technology, cryptographic security, and decentralization as unique advantages that can revolutionize mining by enhancing transaction speed, reducing costs, and improving supply chain transparency and compliance with sustainability standards. Blockchain's transparent and auditable records can enhance business transparency, fostering trust among stakeholders, including investors and regulatory bodies. The technology's consensus mechanisms and smart contracts further promote trust in collaborative ventures. This research provides a foundational understanding for decision-makers in the mining industry to evaluate blockchain's feasibility and potential return on investment, guiding strategic planning and resource allocation for blockchain applications. By leveraging blockchain, mining companies can optimize operations, improve sustainability practices, and establish a robust foundation for future growth, positioning blockchain as a transformative technology in the sector

Jul 10, 2024

By A. T. van Zyl, M. Mthenjane, M. J. Cole

Growing global concern over the impacts of climate change, attributable largely to fossil fuel energy sources, has led to the widely shared goal for a ‘just transition’ to cleaner energy and reduced dependence on carbon-based fuels. As the world’s 14th biggest CO2 emitter and being particularly vulnerable to the impacts of climate change, South Africa must embark on a just transition pathway. This paper reviews expected coal mine closures and associated community vulnerabilities and local governance challenges in South Africa. Decommissioning schedules for all coal-fired power stations and operating coal mines are plotted, and 69 mining host communities and 21 municipalities are mapped, classified, and described. Community socio-economic profiles are measured using a set of SDG indicators and census data and municipalities assessed through financial audits. Our research shows that five coal-fired power plants (8.9 GW) and 15 coal mines (29.5 Mt/a) will probably close by 2030, and a further four plants (14 GW) and 23 mines (106 Mt/a) by 2040. Thus, the shift to cleaner energy will likely occur without the premature closures implied by the just transition. The impact of mine closure on the 2.5 million residents of host communities will be significant, particularly as levels of income, employment, and education are already very low and many municipalities are in financial distress. The South African approach to the just transition needs to take local realities into account and the narrative must support an effective transition that does not undermine energy security and economic growth.

Jun 5, 2023