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Professor R.P. King holds a Ph.D. degree in chemical engineering, which he obtained at the University of Manchester in 1963. After that he lectured in the Departments of Chemical Engineering at the Universities of the Witwatersrand and Natal. From 1968 to 1973, he was Leader of the Chemical Engineering Research Group of the National Institute for Metallurgy at the latter University. Mr C.E. Fivaz, Pr. Eng., is Chief Consulting Metallurgist of Rand Mines (Mining & Services) Limited, and is responsible for the metallurgical activities of the Gold and Uranium Division and the Coal and Base Minerals Division of the Group.

Jan 1, 1984

By P. Marinos, G. Tsiambaos, H. Saroglou

The anisotropic behaviour of “Athens Schist” has been brought out through the testing of specimens with varying orientation of schistosity with respect to the major principal stress under uniaxial, triaxial and dynamic conditions. A large number of results from tests on intact rock specimens of the “Athens Schist” were statistically analysed and evaluated. Le comportement anisotropique des roches du système “Schistes d’ Athènes” a été déterminé sur des épreuves avec une orientation différente de la schistosité par rapport à l’axe de chargement sous des conditions axiales, triaxiales et dynamiques. Un grand nombre des résultats a été statistiquement analysé et discuté. Zur Bestimmung der anisotropen Eigenschaften der Athen Schiefer wurden einaxialen, dreiaxialen und dynamischen Kompressionsversuchen an Gesteinskernen durchgeführt, bei denen die Belastungsachse verschiedenen Neigungen gegen die Schieferung hat. Die Messreihen an anisotropen unzerreissbaren Fels Samplen von Athen Schiefer wurden statistisch analysiert.

Jan 1, 2003

By J. Petersen, T. Moyo, D. Maharaj

This study investigates the effect of ammonium thiosulfate on the leaching of gold from the contacts of unpopulated cut electronic printed circuit boards (PCBs). Studies in the literature show ammonium thiosulfate to be a viable option in comparison to the commonly used but hazardous cyanide leaching route. However, the simultaneous dissolution of Cu interferes with the Au leaching reaction, often limiting the extraction to moderate levels. To optimize the system, an ammoniumthiosulfate system containing 0.5M ammonia, 0.5M ammonium thiosulfate, and Cu(II) sulfate at varying concentrations was studied as an alternative hydrometallurgical option for the recovery of gold from PCB. Tests were done with unpopulated standardized model PCBs (cut to 15 x 30mm pieces). Gold extraction of 47.3% was achieved after a 24-hour leaching experiment with a 0.02M copper background concentration. Further experiments focused using different initial background Cu concentrations (0M – 0.1M) to determine its effect on both gold and copper extractions. An initial Cu concentration of 0.045M resulted in the highest gold extraction, with 93.7% extraction after 6 hours of leaching. Further analysis of the data shows that the kinetic rate of gold leaching is correlated in a first-order dependence with the actual copper concentration in the solution, which increases with the concomitant dissolution of copper and gold from the PCBs. A lower threshold of 0.017M and an upper threshold of 0.15M copper in solution were determined, in between which gold extraction shows this first-order rate increase. The upper threshold is potentially linked to the onset of copper precipitation, which blinds the metal surfaces, slowing further leaching. The findings of this study suggest that in an industrial recovery operation of gold from waste PCB using the thiosulfate method, copper concentrations need to be carefully monitored, and the process should preferably operate with uncut or coarsely cut untreated boards to minimize exposure to copper circuits.

Dec 11, 2024

Professor H.R. Philips was born in South Wales. After graduating with a B.Sc. degree in electrical engineering from the University of Bristol, he joined the National Coal Board's management training programme. Mr B. Moore was born in Coventry, England. He matriculated at Bablake School and then atended Birmingham University, obtaining a B.Sc. Mining Engineering degree in 1953. Professor J .S.J. (J annie) van Deventer matriculated at Swelendam High School. He studied chemical engineering at the University of Stelenbosch, and obtained the degrees of Hons. B. Ing. in 1978 and Ph.D. (Ing.) in 1985. Professor M.D. Brayshaw received most of his education in England but obtained his Ph.D. (Eng.) at the University of Natal. Rock fragmentation by blasting The Third International Symposium of Rock Fragmentation by Blasting will be held in Brisbane, Australia, from 26th to 31st August, 1990. The Third International Symposium of Rock Fragmentation by Blasting is designed to inform delegates on the state of the art in explosives and blasting technology, and to build on the standards of excellence set by the previous symposia in Lulea, Sweden (1983) and Keystone, Colorado (1987). Delegates with an operational, technical, or research focus on blasting will gain from this interactive symposium. Recent journal Mineral resources engineering, edited by C. T. Shaw, T.L. Car, and M. Karmis. London, Taylor & Francis, 1989. Published quarterly. US $107 per year. Risk management The Cost Engineering Association of Southern Africa (CEASA) is to hold its 3rd Biennial Symposium at Indaba, Midrand, on 25th and 26th January 1990. The title of the Symposium is Risk Management in Promotion of Capital Projects. The present political and economic environment in South Africa is characterized by a lack of financial resources, and of technical and management skills, on the part of project owners, designers, and contractors/ vendors.

Jan 1, 1989

By F. Yang, T. Pan, T. Zhao, Z. Shao, D. Zuo

In this paper, the development and applications of robot technique is summarized, and the status and developing direction of China coal mine robotics. A description of the research meaning, frame and key technology of underground salvage robot is given. Keywords: coal mine, robot, special robot, salvage robot.

Jan 1, 2003

The AMIRA Code of Practice and Guidelines for Metal Accounting was developed in response to demand from a number of sponsor companies, including one major platinum producer. Since its publication in 2007, the Code has become widely accepted in the mining industry world-wide as a guide for best practice in metal accounting. With the changes in the structure of the platinum mining industry in South Africa over the last 10 ? 15 years, in particular, the starting up of a number of small platinum producers who must have their concentrate smelted and the contained valuable metals refined by third parties, the need for metal accounting systems that are accurate and have an acceptable level of precision has become even more critical to the success of a platinum-producing operation. The current state of metal accounting in the industry is discussed and possible areas for improved accounting and associated metallurgical efficiencies are identified.

Jan 1, 2012

By R. Strydom, J. H. Selby, J. Slabbert, W. Enslin

Zircon is a naturally occurring silicate of zirconium, which is used in large quantities (~1 million tonnes per annum) for its refractory properties and its extreme chemical inertness. All zircons contain uranium and thorium bound into the crystal lattice, generally at levels up to 500 ppm of uranium plus thorium. This paper focuses on one aspect of the zircon industry—the ability to safely transport large quantities of zircon sand. Currently zircon is not classified as a radioactive material for transport purposes. However, this is because of a factor used in the exemption clauses of the IAEA code on safe transport of radioactive materials. The objective of this study was to determine the validity of this factor, and was submitted as part of an IAEA Coordinated Research Project (CRP). The study is based primarily on measured rather than modelled data and covers the transport of large quantities of zircon from producers in South Africa to customers in Europe. Both occupational exposure of workers and exposure of members of the public have been considered. The transport routes studied cover rail, road, ocean-going ship and inland barge transport of unpackaged bulk products. The study showed that the most exposed member of the public would receive 10µSv/annum,while the most exposed worker would receive 144µSv/annum of exposure. It is concluded that these levels are well below all regulatory limits for such activities involving naturally occurring materials. The study also showed that normal operational exposures are higher than those in accident scenarios, a feature which does not occur with higher activity materials. It is further concluded that the study validates the use of the factor of 10 in TS-R-1, as applied to zircon sand. Additionally it is also concluded that the exemption currently applied to the transportation of bulk zircon sand is valid.

Jan 1, 2003

By P. Valicek

Anglo American Platinum Limited is constantly striving to improve safety and productivity. There are many different initiatives taking place within the organization in order to ensure continued safe operation and profitable ounces for the future. One of the opportunities and potential growth areas that has been identified and is being explored is that of mechanization. In order to do this, the approach that has been adopted by Anglo American Platinum is to fully understand and analyse the current mechanized mining methods. Once each configuration is fully understood, the method can then be optimized and new mining technologies and systems can be developed to overcome the current shortfalls. This paper will discuss a methodology that was developed by Anglo American Platinum (in conjunction with Cyest Corporation) and adopted to optimize the mechanized mining layout and fleet configuration, and will also present the final findings of the study. Due to the impracticability of piloting every possible option in the workplace, extensive modelling and simulation exercises were conducted to determine realistic parameters for productivity and value. The study resulted in a full understanding of mechanized mining systems and their associated layout. From the results of the study a mining / logistic layout was developed which highlighted the following opportunities: 1. Create safe operations through the reduction of personnel in the ?high-risk zone? of stopes 2. Separate machines and personnel by use of remotely operated machines 3. Create focused mining on primary development from the production stoping, thus having dedicated teams on development and stoping. 4. Develop primary development ahead of the stoping activity. This enables: a) Understanding of the geology and subsequent implementation of the correct b) technology (?fit-for-purpose?) required to mine that area based upon this geological knowledge c) Ability to install tipping points ahead of stoping, creating ?immediate stoping reserves?, thus increasing flexibility and reducing production risk d) Improved productivity by having adequate faces available and reduction in re-development to establish faces. 5. Quicker return on Investment due to recovering revenue from ?on-reef development? 6. The layout allows flexibility between stope sections enabling better ?resource sharing? 7. Optimize the long-term ratio of machine makeup of the fleet in relation to the production outputs 8. Creates an agile mining layout allowing rapid response to market pressures. The findings and work presented in this paper is currently being implemented at different test sites within Anglo American Platinum and will demonstrate that improved safety and productivity can be achieved through the adoption of mechanization.

Jan 1, 2012

By K McLeod

{Figure 1} The Placer Dome-Western Areas Joint Venture?s South Deep Twin Shaft Complex, has been planned and dreamt of for nearly 20 years. [ ] The gold reserve at the bottom of these shafts is one of the largest single intact gold deposits remaining in the world today, containing an estimated 57 million ounces. This is about the size of the fictitious reserve created by inventive prospectors for the infamous BREEX scam in Kalimantan about ten years ago and about the size of the reserve Harmony claims as its own in it?s current hostile takeover bid for Gold Fields. So it is certainly of the magnitude that dreams are made of. [ ] {Figure 2} The unique orebody lies in a continuous, highly concentrated, thick deposit, an estimated twelve kilometres along dip and a two kilometre wide strike. Due to the thickness of some sections of the reef, up to 60 metres in places, bulk mining methods will be required for it?s extraction. [ ] {Figure 3} The twin shaft system comprises a main shaft which had an initial design depth of 2765m and a ventilation shaft of 2760m, making them the world?s deepest to be sunk in a single lift. The shafts were

Jan 1, 2005

By C. W. P. Finn

INFACON is of special significance to people in South Africa who are interested in ferro-alloys, because it was in South Africa that the idea of regular international congresses on ferro-alloys was conceived and developed. INFACON 74, the first-ever such congress, was held in Johannesburg from 22nd to 26th April, 1974, being organized by the South African Institute of Mining and Metallurgy, the National Institute for Metallurgy, and the Ferro Alloy Producers' Association of South Africa. Design Awards The Design Institute is inviting entries for the 1981 Shell Design Awards. Any product that falls into the three categories shown below, and that was designed in South Africa and is in production, is eligible for an award. Since their inception in 1970, the Shell Design Awards

Jan 1, 1981

Termination of membership In accordance with By-Law 7.6.1. of the Constitution of the Institute, the names of the undermentioned members have been removed from the membership register. Colloquium and General Meeting A General Meeting and Colloquium on 'Heavy-medium separation and ore sorting' was held on 18th September, 1974, at 09h15, in Kelvin House, Johannesburg.

Jan 12, 1975

By M. Z. Emad, N. Abbas, Y. Majeed

Room-and-pillar mining is commonly employed for the extraction of rock salt in undergroundmines. Pillar stress is a major concern in these mines as it is directly related to stability and mineralrecovery. In this study a flat jack method was used to measure pillar stresses in three undergroundrock salt mines in Pakistan. The field work included determination of in-situ stress, in-situ elastic modulus, recording of field variables (pillar length and width, height and width of opening, opening width to height ratio, extraction ratio, and overburden height) and collection of salt block samples. The geomechanical properties of rock salt (uniaxial compressive strength, Young’s modulus, Brazilian tensile strength, and density) were also determined to estimate overburden stress, pillar strength, and factor of safety (both estimated and actual). It was found that the measured pillar stresses are proportional to the overburden stress values, with their magnitude ranging from 6.05 MPa to 11.97 Mpa, and the pillars were found to be stable. Regression analysis was performed to develop statistical models for in-situ stress and in-situ elastic modulus. Finally a quick guideline chart was developed to determine the suitable length of pillar for a given span and required level of safety.

Jun 5, 2023

Despite the media's use of the mining industry as a whipping boy over its perceived attitude towards the environment, the facts remain that the only legislated requirement in the SA Statute Books for any form of environmental impact-assessment prior to development is to be found in the Minerals Act in the form of an EMPR. Not only is our industry complying with this requirement, but moves are afoot to set up environmental management systems for existing operations in preparation for seeking accreditation under ISO 14001 when published towards the end of this year. On how broad a front are we advancing? ? Is the industry equipped to handle these challenges? ? Does it have the determination to overcome its problems? ? Do we realise that failure may mean the loss of markets overseas to competitors who can meet the international standards? ? Where are the shortcomings and when must our efforts be focussed?

Jan 1, 1996

By J. A. Cruise

From 27th to 29th September, The South African Institute of Mining and Metallurgy held a Colloquium on Equipment Alternatives in Underground Mining in Johannesburg. The Colloquium, which was highly successful, was held concurrently with the 1988 Electra Mining Exhibition. Particle characterization The Fourth European Symposium on Particle Characterization is to be held in Nirnberg, West Germany, from 19th to 21st April, 1989.

Jan 1, 1988

By D. F. Malan, T. E. Oates

A recent experimental pillar extraction project at a UG2 bord-and-pillar mine presented a unique opportunity to compile a new pillar database. Currently, the South African hard rock bordand- pillar mines are designed using the Hedley and Grant formula with a modified K-value. This empirically derived formula was developed for uranium mines in the Elliot Lake district of Canada. The use of this formula for the design of pillars in South Africa is questionable. Very few pillar failures have nevertheless been observed and its current calibrations for the various reef types are possibly too conservative. A new UG2 pillar database of 66 pillars, of which seven are classified as failed, was compiled by the authors. This enabled a revised ‘first-order’ calibration of the K-value for the Hedley and Grant formula. The new estimated value for the UG2 is K = 75 MPa. This gives a pillar strength that is more conservative than the PlatMine formula. This work should nevertheless be considered as only a preliminary calibration as the database was small. Further work is also required to determine whether the exponents in the formula for the width and height parameters are appropriate for UG2 pillars.

May 3, 2023

By Z. Botha

Sheryl Sandberg, the COO of Facebook, published a book titled 'Lean In', where she invites women to sit at the table. In summary, to 'sit at the table' entails not only embracing opportunity, but to actively seek out opportunities in leadership positions. Sandberg points out that, unfortunately, apart from institutional obstacles, a woman's own perceived limitations have a negative impact on her leadership ambitions. To create an environment where diversity will flourish, where everyone has a seat at the table and everyone has a voice, safety must be established first. To establish safety within a diverse team, there is power in relationships and connections. This study will first and foremost review theories in literature as to why diversity and inclusion are so important and the value that diversity brings to our industry. The study also recommends a few focus areas for improving diversity and inclusion in the industry.

Sep 1, 2022

ADVANCES IN EXTRACTION METALLURGY AND REFINING A symposium organised by the Institution of Mining and Metallurgy will be held in London from 4th to 6th October, 1971. Particulars can be obtained from: The Secretary, Institution of Mining and Metallurgy, 44 Portland Place, London WIN 4BR, ENGLAND. ICAMC -71 - HUNGARY The Third International Conference on Automatic Control of Mines and Collieries will be held at Balantsfured, Hungary from 27th to 30th September, 1971. Further particulars can be obtained from: ICAMC - 71, Budapest 3, P.O. Box 115, HUNGARY. AUSTRALIAN INSTITUTE OF MINING AND METALLURGY Illawarra Branch A symposium on "Blast Furnace Injection" is to be held at Wollongong University College from 15th to 17th February, 1972. About 20 papers on various aspects of blast furnace injection will be presented, including two on nonferrous furnaces. Further particulars may be obtained from: N. Standish, Chairman, Symposium Committee, Wollongong University, Australia 2600.

By P. O. Osifo, K. Premlall, X. Goso, R. H. Matjie, M. R. Mulaudzi, J. R. Bunt, K. Mphahlele

This study investigates the transformation of pyrolytic spent tyre-derived char and crumb rubber into high-performance activated carbon chars for industrial wastewater remediation. Utilising an in-house macro-thermogravimetric analysis system under an argon atmosphere, spent tyre-derived activated carbon char were synthesised via physical temperature activation and aqua regia demineralisation. Comprehensive characterisation using x-ray diffraction, Raman spectroscopy, and scanning electron microscopy, revealed a predominantly amorphous structure with nanoscale crystallites (~1 nm) and active surface functional groups. Proximate analysis confirmed that both crumb rubber and leached tyre crumb rubber with aqua regia derivatives achieved favourable compositions (ash ≈ 9.6%; fixed carbon ≈ 84%), comparable to commercial activated carbon (AC). At an optimal activation temperature of 850°C, the char of tyre crumb leached with aqua regia variant exhibited a significant surface area of 300 m²/g. Crucially, the tyre crumb char produced at 850°C variant developed a pore volume of 0.8 cm³/g—effectively doubling that of commercial activated carbon (0.4 cm³/g)—facilitating the sequestration of large organic molecules. In application tests using high-strength starch wastewater, char of tyre crumb leached with aqua regia and tyre crumb char, both produced at 850°C, achieved total organic carbon removal efficiencies of 60% and 50%, respectively, bridging the performance gap between waste-derived and commercial adsorbents. These findings validate waste tyres as a viable, low-cost precursor for industrial-grade adsorbents, offering a sustainable circular economy route for tyre valorisation and reduced industrial disposal costs. Future research will focus on kinetic modelling and the recovery of zinc from spent tyre-derived activated carbon char residues.

Mar 30, 2026

By C. Cunningham

The process of initiating opencast blasts through long cables is onerous. An obvious alternative is to replace these with radio controlled firing apparatus. Such devices appear from time to time and with the advance of telecommunications, more are likely to appear. However, there are two crucial and seemingly intractable obstacles to overcome: firstly, the problem of malfunction of the system, which can either fire prematurely or go into a state of suspense in which it is unknown whether firing might unexpectedly occur, and secondly, the problem of terrorism, as such a system could provide the capability for an off the shelf remote bomb. The issues of accessibility and electronic reliability when linked to explosives in a mining environment have to be demonstrated to be adequately covered before serious consideration should be given to these systems, up to now largely confined to military applications.

Jan 1, 2003

By Jannie Maree, Dieks Theron, Ryneth Nengovhela, Patrick Hlabela

In extracting base metals from ore bodies, sulphide as well as oxide, the main environmental concern is sulphur, whether in the form of sulphurous gases or sulphate in liquid form. Generally sulphur is in over supply in developed countries mainly because of strict legislation to capture it. In developing countries on the other hand there is usually a shortage of sulphur because of less strict environmental legislation. Africa falls in this second category and the African continent imports substantial amounts of sulphur despite the fact that large quantities of sulphur is emitted by smelters, thermal power stations, coal mines, fertilizer manufacturers and others. Other than making acid from gaseous emissions, existing methods to capture sulphur from gaseous and liquid effluents are uneconomical and it ends up in the environment either as ammonium sulphate (from gaseous effluents) or as gypsum (from liquid effluents). The CSIR?s Environmentek and Pyroserv has developed a process whereby gaseous sulphur emissions and sulphates in liquid effluents can be economically captured and converted into elemental sulphur and metal carbonates. The elemental sulphur is of high purity as it is precipitated from a gas stream and is readily marketable. The metal carbonates (barium or calcium) can be recycled back to the process or marketed. The only harmful byproduct of the process is carbon dioxide. Should natural gas or methane be available the carbon dioxide could be reduced by about one third. Should solar, wind or hydro energy be available to generate hydrogen the carbon dioxide emissions would be zero. Employing this technology could make Africa independent of sulphur imports and furthermore reduce the impact of acid rain and seepage of sulfate from gypsum and other waste dumps into the environment.

Jan 1, 2005