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By I. Ince, S. Kahraman, M. Rostami, B. Dibavar

The density, porosity, and strength of rocks are fundamental in the design of geo-engineering projects. Determining these properties requires the preparation of smooth core samples, which is usually impossible for soft rocks. Besides, only fragmented samples may be available in some projects. A method for predicting rock properties from rock particles such as drilling debris would therefore be useful. This study was undertaken to develop prediction equations for compressive strength (UCS), tensile strength (BTS), density, and porosity values from the crushability index (CI) obtained from rock fragments. The results showed that UCS, BTS, density, and porosity were strongly correlated with the CI. The physical characteristics and strength of rocks may be predicted with the help of the derived equations. The CI test is a valuable tool for estimating rock properties in drilling projects and in situations where core specimens are not available.

Mar 14, 2024

By M. Getz, G. Asbjörnsson, M. Evertsson, E. Clausen

The mining and minerals processing industry is gradually being digitalised to improve efficiency and reduce waste. One aspect of this transition is to ensure that relevant process-data in sufficient quality and quantity is given to the operator in the right format and at the right time to improve decision-making. Augmented reality (AR) can serve as a potential ICT-based support tool for human operators to achieve this goal. With AR, virtual information is combined with the real world in real-time. Therefore, AR technology has the potential to fulfil the need for improved data visualisation in Industry 4.0. This article is the result of a collaborative effort of Chalmers University of Technology and RWTH Aachen University to identify selected state-of-the-art applications of AR that are currently being applied in the mining and minerals industry or selected related industries. This paper aims to show opportunities for the application of AR in the mining and mineral processing industry with selected conceptual applications. This paper concludes with several requirements identified as necessary to implement the conceptual applications of AR in the mining and minerals industry. Keywords: Augmented reality, mining, mineral processing

Jan 1, 2020

By L. Godfrey, Z. Nontso, F. Magweregwede, B. Maphalala, S. Khan

The aim of this paper was to establish if mineral resource scarcity is a driver for South Africa to transition to a circular economy. The project objectives were achieved by investigating economically viable, and critical or strategic minerals remaining in South Africa, as well as resource scarcity, as a driver for South Africa to transition to a circular economy. The study found that some minerals in South Africa, such as iron ore, lead, manganese, gold, and cobalt have less than 50 years of economically viable mining remaining. At least 18 minerals can be classified indicatively as critical or strategic: aggregates, bauxite, chromite, cobalt, copper, gold, graphite, iron, limestone, lithium, manganese, nickel, phosphorous, platinum group metals, rare earth elements, silver, titanium, and vanadium. The classification was based on the minerals’ economic importance, supply risk, and potential use in the development and manufacturing of emerging technologies. The findings suggest that the scarcity of mineral resources is a critical driver for the country to transition to a circular economy. Other identified drivers include socio-economic factors, climate change commitments, and business objectives. All minerals are non-renewable resources and at risk of depletion, therefore sustainable extraction and use are critical. Priority should be directed at investigating circular economy opportunities and substitutes for commodities at risk of being depleted within the next 50 years. There is an opportunity for South Africa to transition from a minerals export-based model to one that promotes local mineral beneficiation and manufacturing of end products.

Mar 5, 2025

"Chairman: Prof A. E. H. BLEKSLEY Rapporteur: Prof J. ELBRONDPanel Members: Prof J. C. Griffiths, Prof T. E. Hawkins, Mr A. C. Langton, Mr M. Splaine, Mr A. WeissThe reasons for failure of computer applications in the mineral industry and the direction of future developments.The Chairman opened the discussion by elaborating on the disappointment felt by some authorities with the lack of progress in the application of computers in the mineral industry during the last ten years, and posed the question to the panel : 'Do you agree that the computer age has not come up to expectations?'Mr Langton said that although there seemed to be a tremendous amount of brainpower applied to the theoretical side, he thought that the production men had not got all the help from computers that could have been given to them. The computer, said Prof Griffiths, is as yet a new tool which should not be used to do old things in old ways. To learn to use the computer will take time. After all, he said, it had taken 400 years after the introduction of the printing press to achieve general literacy, and perhaps it will take 40 years after the introduction of the computer to achieve `numeracy'.In Mr Weiss' view, the reason for the feeling of disappoint¬ment lay in the focussing of attention on the computer. The blame, if any, lay with the people surrounding the computer, that is, the analysts and programmers, to whom the emphasis should be shifted.Prof Hawkins said that he thought that some applications of the computer in the mineral industry had been successful, such as, for example, the compilation of payrolls. Reasons for failures in other areas were to be sought in the fact that the people connected with computers had failed to realise that they were merely part of a system. They had not understood the power structure of the organization which their work tended to change, and were therefore not prepared for the inevitable conflict with the production men.In Mr Splaine's view the production man had not received the assistance he could have had from the computer people because he may possibly not have allowed this to happen.Prof Bleksley concluded from these opinions that the promise which computers had ton years ago had not been fulfilled and added that the opinions expressed by the panel had intruded on his next question which was: 'Is the reason for this that people are involved?Prof Hawkins elaborated on his previous theme, namely, that of computer people in relation to management. Com-puter people, he said, were trying to impose change on management but were not prepared to share the responsibility for these changes. In fact, they wanted their work to be distinct and separate, and, as far as management was concerned, changes would be made when management believed that these would be less agonizing than no change at all."

Jan 1, 2014

By N. C. Steenkamp

Lightning has been observed in dust clouds following open-pit blasting. It is proposed that the occurrence of this phenomenon is related to the physical composition and characterization of the mineral fines that comprise the bulk of the dust cloud. Silicate minerals, which are susceptible to fine fracturing during blasting, generate the initial charge. This is further enhanced by collisions and friction during the turbulent upcast in the post-blast dust cloud. Varying size fractions result in different rates at which these particles drop out of suspension and create a secondary temperature gradient. This results in the creation of two charged zones and increases the potential of developing a discharge in the form of lightning. The ideal prevailing meteorological conditions need to be windless to minimize the effect of particle dissipation and have sufficient moisture toenhance the potential of generating lightning.

Apr 14, 2024

By G. Asbjörnsson, E. Hulthén, P. Papadopoulou, C. M. Evertsson

Crushing plant managers need to assess, manage, and communicate the environmental impact induced by their crushing plant operations as a step towards the sustainable development of the company. However, performing reliable environmental impact calculations of crushing plants can be challenging when the availability of operational and emission data is low, and when the company’s environmental expertise is not adapted and connected to plant operations (or does not currently exist). To address these challenges, this paper proposes a practical approach where the lifecycle assessment methodology (LCA) is combined with process simulations in a web-based tool. To describe what functionality such a tool should have to be incorporated into a company’s workflow, the system that surrounds a crushing plant is analysed. Further, a case study with a three-stage crushing plant is introduced to showcase how the simulated power draw results produced with the beta version of the tool can be compared to measured sensor data from the crushing plant for one operational day. The results indicate that the simulation tool can provide an adequate estimation of the specific energy for the different material fractions and give an overview of the environmental impact of the process caused by electricity and explosives consumption. Plant managers and operators can use this tool to calculate the environmental impacts of their plant and simulate how different operational strategies influence them. Keywords: LCA, environmental impact, coarse comminution, crushing plant

Jan 1, 2020

By W. F. McKechnie

"Southern Africa is generally thought to be well explored, with only limited potential for major new diamond discoveries. However, Chiadzwa in Zimbabwe and reports of a significant new kimberlite find in Angola are testimony to the dangers attached to an attitude that ‘there is nothing left to find’.Since the major discoveries in the central interior of South Africa in the 1870s, diamond exploration in the region has been led by market and political factors that influence the key exploration drivers of opportunity and value proposition. Unexpected new discoveries by new players always impact on existing producers and, from time to time, denial of opportunity through political or protectionist policies has inhibited investment in exploration.Entrepreneurial exploration appetite in southern Africa will be tempered by the potential value equation and security of investment. Overlaid on this, developments in diamond recovery technologies provide opportunity to reinvigorate current mines and old prospects previously considered too difficult or costly to exploit. Position on the cost curve will remain a key factor for survival in an increasingly competitive environment. IntroductionThe diamond industry in southern Africa boasts a history of 150 years of discovery and mining, forming the cornerstone of development of the core, modern economies at the southern tip of Africa.Since the discovery, in the 1860s and 1870s, of the secondary diamond placers and primary diamond-bearing kimberlite deposits in the central interior of the then Cape Colony and Orange Free State, southern Africa has endured as the pre-eminent diamondproducing region in the world. Notwithstanding periodic competition from significant new discoveries in other parts of the globe and the paucity of recent, new discoveries in the region, its ranking is unlikely to change in the short to medium term.In a geological context the region contains the Kaapvaal-Zimbabwe and Angola-Kasai cratons, identified in terms of Clifford’s rule as areas inherently prospective for diamonds, being underlain by portions of the Earth’s crust that are tectonically stable and older than 1.5 billion years (Clifford, 1992). Although the Democratic Republic of Congo (DRC) would, in a geographic context, be considered to be part of Central Africa, for the purposes of this review it is included in southern Africa since northeast Angola and the adjacent parts of the DRC form part of the same geological terrane and diamond production from both countries needs to be considered together. Historical and current diamond production from the northeastern parts of the DRC around Kisangani is not considered to be significant and its inclusion in the overall numbers for the DRC does not materially affect the overall picture presented here."

Feb 1, 2019

By J. Cilliers, R. Seitz, D. Drinkwater

Mineral processing produces a saleable product from high-cost ore. The Mineral Processing Engineer must constantly improve the separation to create the most value from the ore and reduce the associated costs. Graduate Metallurgists (or Chemical Engineers) have had the university theoretical training required, but often are illprepared to perform their plant roles. The in-work Metcelerate programme was designed specifically to develop the practical skills that Mineral Process Engineers require, by combining three key elements: 1. Knowledge transfer through self-paced, on-line training; 2. Practical skills acquisition through assessed, practical plant exercises; 3. Skills development through online tutorials. A final process improvement project adds significant value to the operation that far exceeds the training cost. Experience from Metcelerate clients has indicated improved staff retention, greater confidence, and pro-active process intervention.

Jan 1, 2023

The 94th Annual General Meeting of The South Mrican Institute of Mining and metallurgy was held in the Gold Room of the Transvaal Automobile Club in Johannesburg on Wednesday, 14th August, 1991. Obituaries The President announced the deaths of the following members of the Institute: Honorary Life Fellow and Past President

Jan 1, 1991

By A. Ball

A fully instrumented laboratory drilling machine is described. It is designed to produce realistic drilling conditions with diamond microbits of 20 mm diameter. A computer-controlled data-logging system records the net power consumption, rotational velocity, bit thrust, torque, and penetration rate. Tests can be conducted under conditions of set thrust and rate of advance. In the tests reported, there is a significant correlation between the rock drilability and the measured rock properties of relative abrasion resistance and uniaxial compressive strength. Wear of a diamond bit is a crucial factor that cannot be determined simply from rock properties. Realistic drilability testing with appropriately scaled microbits is a convenient and economical way of evaluating diamond-bit performance and determining rock drilability.

Jan 1, 1990

By F. P. A. Robinson, C. R. Thomas

Stress-corrosion studies on materials used for surgical implants * by C. R. THOMAS and F. P. A. ROBINSON Samples of Vitallium (a cobalt-chromium alloy), 316L stainless steel, and titanium T318 were subjected to the boiling magnesium chloride test so thattheir susceptibility to stress-corrosion cracking could be determined, and their behaviour under service conditions was then assessed. Stress-corrosion cracking was confined to the stainless-steel samples, while gross pitting was detected in the samples of forged Vitallium. It was concluded that the use of stainless steel should be avoided for long-term surgical implants. Surface imperfections on the stainless steel are generally the cause of pitting, from which stress-corrosion cracks are sometimes propagated.

Jan 11, 1976

By L. Wade

The advent of relatively cheap computing power has precipitated a rapid growth of computer usage in the mining industry. In order to obtain most benefit from this development a need is recognised for the future mining graduate to be trained in computer literacy. This paper outlines the type of training required and describes progress to date with such a programme at the University of the Witwatersrand. Certain challenges concerning the teaching effort are discussed.

Jan 1, 1987

PREFACE During the past year, the Council of the SAIMM undertook a major strategic-planning exercise to review all its current activities, and to redefine its scope and objectives in the light of changing circumstances. The following are the four main concerns that prompted Council to take stock of the situation. (1) Over the past five years, the SAIMM has become heavily involved in a variety of new activities. (There are many examples, of which the expansion in book publications and the establishment of physical metallurgy as a third major discipline with its own colloquia and schools are perhaps the most important.) While these new activities have considerably broadened the SAIMM's scope, they have resulted in a significant increase in the day-to-day workload of the President, Office Bearers, and Council members, and of the secretarial staff based at Kelvin House.

Jan 1, 1986

By k. Lebecki, S. Trzcionka

The prototype and test results of the instrument for quick determination of incombustible content in deposited dust as a protection against coal dust explosion propagation are presented. Presently existing methods do not permit to obtain quick information about incombustible content, needed for the proper protection of workings. As the operating principle for the e instrument the dependence of reflection of infrared radiation intensity on incombustible content in the sample is chosen. The construction is based on the modern electronics. The measurement will be done at the sampling site. The range of the instrument is 0-100% of incombustible, direct reading, autonomous supply, weight no more than 0.5 kg, and is intrinsically safe according to EN Standards. During the Conference the instrument will be commercialized.

Jan 1, 2003

By G. Ferrara

The mathematical framework of a well-established model proposed earlier by the authors for the screening process is briefly recalled. Some numerical methods for the application of the model, concerning numerical solution of the equations and parameter estimation, are indicated. Some applications of the model to improve screening operations, sizing of screen, simulation of screening and of integrated plant operations are discussed, and the computer software to be used for these purposes is described in detail.

Jan 1, 1987

By M. Kannenberg

When coal properties are estimated geostatistically for mine planning in the hardcoal industry, there is one important supposition which influences the reliability of prediction of economically profitable parts of the deposit. This is the fact that activities in hardcoal exploration and mine planning are characterized by distinct levels of information and knowledge upon which decisions of economic import must be based, for example, whether exploration should proceed or not, or which methods and strategies should be used to maximize search efficiency. To get more reliable results for mine planning, in particular, advanced kriging methods (e.g. conditional simulation) have to be introduced and checked for their reliability in historical analyses (post-mortem studies). By using this feedback, kriging results from underground samples or production data can be compared with results gained by advanced geostatistical methods from exploration boreholes.

Jan 1, 1987

By J. O. Claassen

A study was initiated and solutions implemented to address the root causes of a 30%?40% lower than predicted product yield achieved at a Mpumalanga coal mine. A holistic MRTM approach, which focused on improving exploration, geological sampling and analysis, geological modelling, planning, mining, and beneficiation practices, was used. The study indicated that deviations in the planned versus actual yields at the DMS plant were caused mainly by incorrect geological yield predictions, high and variable levels of dilution, and near-dense material, as well as the textural properties of the ore. Keywords MRTM, mining value chain improvement, Witbank coalfields, complex geology.

Oct 1, 2013

By N. R. Shoko, J. Chirasha

Refractory design remains the most fundamental factor in furnace construction. Refractory design details and proven technology consideration is of paramount importance to come up with an optimum furnace life and to maintain productivity in the life span of the furnace lining. The failure to produce a technically or operationally durable refractory design lining could give rise to pre-mature deterioration of the refractory lining and furnace shell. The premature failure of the furnace lining will lead to extensive heat losses, furnace bath shift, change in taphole orientation and alteration of the Pitch Circle Diameter. A combination of these were experienced at Zimbabwe Alloys? new high carbon ferrochrome furnace. The Zimbabwe Alloys experience has shown an excellent furnace performance in the first two years of operation although signs of an anomaly showed within the first six months of the new furnace. Production slowed down due to induced problems from refractory failure causing furnace distortions impacting on the availability of the furnace and smelting capacity. This paper presents the lessons learnt, measures taken to deal with the premature failure and constraints within which the situation was managed.

Jan 1, 2007

By N. J. Alderman, D. J. Clowes, N. I. Heywood

The effects were studied of the presence of comminuted flint on the rheological characteristics of chalk slurry pumped through a 92-km long pipeline from Kensworth Quarry to Rugby Cement Works in the UK, and their impact on the pipe flow conditions. Flow curves were measured for 63different chalk slurry samples; these were described by the Bingham plastic model. In addition to observing trends in the yield stress parameter and plastic viscosity in the model with variations in both flint concentration and dispersant additive, use was also made of slurry viscosity values at a reference shear rate of 60 s-1for the pipe flow. It was found that chalk slurry viscosity decreases with increasing flint content up to 10% by weight for a given additive concentration, and increases with increasing additive concentration from 0.7 to 1.0%, for a given flint content. The pipeline flow regimes were identified using the critical value of the Bingham Reynolds number for laminar flow breakdown. For Bench 11 (quarry bottom) chalk slurries, it was observed that all sections of the pipeline operate in the turbulent flow regime for the nine different formulations and for the three pipe diameters used along the pipeline. However, this was not always the case for Bench 1(quarry top) slurries. It was therefore recommended that chalk slurries prepared from Bench 1 should not be used because of the strong likelihood that laminar flow conditions will occur owing to the presence of higher clay concentrations within this bench. This, in turn, will lead to an unsafe operation of the pipeline because of the potential for coarse particle settling. Likewise, blending of chalk from Bench 1 with the lower benches such as Bench 11 could be problematic and this requires further experimentation.

Jan 1, 2007

By N. Patel

Many factors, from engineering and design to supply, installation, and operation affect the service lifespan of cast refractory linings. If a shortcoming occurs at any of these stages, the lining lifespan can be drastically reduced. Although not every aspect that can affect a cast refractory lining?s lifespan is outlined here, a few key points are highlighted, with an emphasis on the various installation parameters. Keywords cast linings, refractory lifespan, lining engineering and design, lining supply, lining installation, curing, dry-out.

Aug 1, 2013