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By J. C. Steinhobel

Answers to questions raised at the Symposium on Trackless Mining in Metal Mines Questions by J. O. Steinhobel (1) When rubber-tyred equipment is used for the delivery of stores and items of equipment, how is heavy material-pipes, rails, timber support, ventilation columns, etc.-dealt with? 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.

Jan 9, 1973

W. C. J. van Rensburg and D. A. Pretorius (H. Glen ed.). South Africa's strategic minerals - pieces on a continental chessboard. Johannesburg, Valiant Publishers, 1977. 170 pp. RI2,00. (Obtainable from The Librarian, Foreign Affairs Association, P.O. Box 26410, Arcadia, 0007 South Africa.) This book provides the answers to many questions relating to what minerals South Africa produces and in what quantities, what mineral industries and trade she practises, and what mineral resources and reserves she possesses.

Jan 1, 1978

By J. D. Stone, I. D. Brumby, J. D. Inch, C. J. Beukes

A. Continuous miners, and their operation at Bosjesspruit Colliery J. D. INCH*, B.Sc. (Min.), M. I. Min. E. (Visitor) A brief description is given of the main types of continuous miner and their incidence of application in South Africa. Definitions and descriptions of the design parameters and components of the main cutting head are given. together with an outline of the modifications carried out to improve machine cutting performance. An account is given of experience with the application of water infusion to suppress airborne dust during continuous-miner operations. B. The selection and performance of continuous miners at Matla Coal by J. D. STONE, B.Sc. Eng. (Min.,) M.B.L. (Graduate) The reasons for the choice of continuous miners for the development of accesses and the winning of coal in a modern underground coal mine are discussed. It is shown that, at relatively low depths, the extraction rate as well as the costs are more favourable than those of proved total extraction methods. The selection of a continuous miner is largely dictated by factors such as production rate, capital and running costs, imported content and the extent to which local content and manufacturing are to be increased, manpower requirements, seam thickness, expected floor and roof conditions, and maximum cutting height. The present inherent shortcomings of continuous miners, such as inefficient continuous transportation of coal away from the miner and the lack of an infinitely variable traction to match the sumping speed with the feasible penetration speed, are pointed out. Specific problems encountered and the methods of solving them, as well as a planned trial with a heavy-duty continuous miner, are discussed. C. Continuous mining within the Tavistock Group of collieries I. D. BRUMBY.Dip. Min. (Visitor) The Tavistock Group of collieries is situated some 25 km south of Witbank. The three collieries comprising the Group are Tavistock Colliery, Phoenix Colliery, and South Witbank Coal Mines. Continuous mining is practised to some degree at all three collieries. This system of mining was introduced at Phoenix during 1976, South Witbank during 1978, and Tavistock during 1979. For the twelve months ended June 1979, continuous mining accounted for 1,7 Mt of the 4,5 Mt hauled from underground. All the continuous miners introduced to date have been of the rotary-drum type. D. Pillar extraction at Usutu Collieries using continuous miners by c. J. BEUKES(Visitor) In 1969 Usutu Collieries began pillar extraction with conventional mechanized equipment. This was very successful, but certain disadvantages could be eliminated if continuous miners were used instead. In 1976 the first continuous miner was introduced for this purpose; this proved so successful that a second unit was introduced in 1977, and pillar extraction by conventional equipment was discontinued. By the end of 1978, 1,3 Mt had been mined from pillar extraction by continuous miners. This paper describes the method in some detail, and indicates that the operational costs are lower than for conventional bord-and-pillar mining. Defect solid state A one-day multidisciplinary symposium entitled 'The Defect Solid State '80' will be held under the auspices of the Solid State Physics and Materials Science Subcommittee of the South African Institute of Physics at the University of the Witwatersrand on Monday, 14th July, 1980, following the Twenty-fifth Annual Conference of the South African Institute of Physics.

Jan 1, 1980

By D. I. Nicol

An assessment is made of the possible scope for the use of activated charcoal as the solid adsorbent in an upflow fluidized-bed contactor, and a pilot-plant programme for the recovery of low concentrations of dissolved gold in this contactor is described. It was found possible to produce an effluent that contains less than 0,01 p.p.m. of dissolved gold.

Jan 1, 1997

By D. M. Meyer, K. Auerswald

The production of electrolytic manganese in South Africa by M. HARRIS, Pr. Eng., B.Se. (Eng.) (Fellow), D. M. MEYER, Pr. Eng., B.Se. (Meeh. Eng.) (Visitor), and K. AUERSWALD (Visitor) The decision to construct the first electrolytic manganese plant in South Africa was important and farreaching. After evaluating the results of the pilot plant operation, the first South African producer, Electrolytic Metal Corporation (Emcor), established a plant in Krugersdorp. Initially, there were many process problems that had to be InvestIgated, and, after these had been solved and many operating parameters had been established, manganese was successfully produced. When the Delta Manganese plant in Nelspruit was planned, cognizance was taken of the fact that, if peak efficiencies were to be maintained, the process must be operated between fairly narrow parameters. Instrumentation was therefore installed to control the process automatically wherever possible. The main features of the Delta Manganese operation are outlined, with a brief description of each stage of the process from ore milling through to electrowinning and packing of the metal. It is concluded that much benefit can be obtained from further research work into process improvements and into the exact effect of certain variables on plant and current efficiency.

Jan 2, 1977

By N. V. Moraka

Mining companies are required by law to improve representation of women on their boards. However, progress in this regard has been slow. Boards of directors play an important role in formulating corporate strategy, risk assessment, and effective governance for sustained financial performance. Although some women have successfully maintained board seats, others have been unable to do so. It is difficult to ascertain whether women are being appointed as tokens to satisfy social pressures, as little is known about the experiences of women board members in mining, which may inform or refute tokenism. In-depth interviews were conducted with 20 women and 16 men across six listed mining companies. Thematic data analysis revealed evidence of tokenism where recruitment to mining boards is compliance-based and is informally driven by influential directors. Adverse boardroom experiences that further confirmed tokenism were reported by women, such as disregarding their contributions, condescending behaviour, and limited influence in decision-making, while other women sought to validate their competence and oppose social exclusion. This study recommends that a strong Board Chair and nominations committee is critical to ensure sustainable recruitment of competent and suitably qualified women; and further foster a culture of inclusivity and valuing gender-diverse boards.

Dec 13, 2023

By F. L. D. Cloete, A. K. Haines, T. D. Sampson, T. H. Tunley, W. A. M. te Riele

The recovery of zinc from pickle liquors by ion exchange A. K. HAINES. Ph.D. (Visitor) T. H. TUNLEY. B.Sc;.(Chem.Eng.)(Visitor), W. A. M. TE RIELE. pr, Eng.. Ph. D. (Visitor), F. L. D. CLOETE. M.Sc. (Chem..Eng.)(Visitor), and T. P. SAMPSON. Pr. Eng.. BSc, (Chem.Eng,). B. Econ. (Visitor) Picklers and galvanizers in and around Johannesburg are encountering an ever-increasing problem in disposing of spent liquors from their hydrochloric acid pickling baths. Particularly troublesome is the zinc-contaminated liquor that is produced as a result of the clean-up of rejects from the galvanizing operation. Because of the volatility of zinc chloride. this liquor presents difficulties when processed in a conventional pyrohydrolysis acid-recovery unit. The paper describes the Metsep Process. developed by the National Institute for Metallurgy and Woodall-Duckham S.A. (Pty) Ltd. which involves the use of continuous ion exchange for the separation of the zinc from the pickle liquor. and the use of liquid-liquid extraction for the conversion of zinc chloride eluate to salable zinc sulphate. A description of laboratory and pilot-plant tests is given. and the approach used in the design of a full-scale continuous- ionexchange plant is outlined.

Jan 11, 1973

By N. C. Joughin, A. C. Buckmaster

The use of face conveyors in gold mines by N. C. JOUGHIN. B.Sc. (Eng.). Ph.D. (Wits) (Member) and A. C. BUCKMASTER; M.A. (Cantab.) A mechanized stope-cleaning system has been developed around an armoured face conveyor, which was tested on the surface and in two underground trials. In the second underground trial, an average face advance of 8,5 m per month was obtained with a labour productivity of 27 ca/worker/month on a two-shift blast cycle. Two new face cleaning systems have been built, each incorporating an armoured face conveyor, a loading plough, a collapsible self-advancing barricade, and an integral roof-support system. These are about to be tested. A new type of reciprocating flight conveyor is being developed for stope use. This is cheaper, lighter, and more compact, and exhibits better wear characteristics, than an armoured face conveyor. In the early stages of the trials, this conveyor frequently achieved a singleshift blast cycle. It should be possible to achieve face advances of up to 40 ca/worker/month with a consistent one-shift blast cycle. The use of drill rigs and a self-advancing roof-support system would improve the productivity to over 50 ca/worker/month.

Jan 2, 1976

Contribution by W.D. Ortlepp? The authors are to be commended for publishing their interesting view of an aspect of deep-level mining technology that is becoming increasingly topical and vitally important. This is the second paper in the journal within four months to deal with the crucial needs of highly stressed tunnel construction, the other being the paper on the design and testing of rockburst support in the February 1994 issue. Both papers re-examine important innovative ideas that are more than a quarter of a century old, but that have not yet been implemented by the industry. It is to be hoped that they will now, taken together, serve as a new starting point for a definitive examination of what constitutes proper tunnel-support design. There can be no question that the need to develop a design approach that will solve the problems of tunnelling at depths of 4000 m or more has now become crucial. Contribution by A.M.J. Vervoort* Although the overall paper is very interesting and the future research (comparison between numerical simulations and underground measurements) will be very challenging, I would like to make some remarks regarding the set-up of the numerical model and the interpretation of the elastic results.

Jan 1, 1995

A Colloquium and General Meeting were held on 17th March 1971, the theme being 'Future trends in steel production'. Mr V. C. Robinson (President) was in the Chair. The Colloquium was attended by 121 delegates and was opened by the President at 10 a.m. OBITUARIES THE PRESIDENT: 'It is my sad duty to announce the death of the following: F. O. Read, Fellow, who joined the Institute in 1957 and passed away on 13th January, 1971. P. G. M. May, Member, who joined the Institute in 1969 and passed away on 10th August, 1970. R. J. J. Rademeyer, Life Fellow, who joined the Institute in 1942 and passed away on 23rd September, 1970. As a mark of respect to the memory of the deceased and in sympathy with the bereaved I would ask you all to rise and observe a few moments silence. CONFIRMATION OF MINUTES THE PRESIDENT: 'May we confirm the minutes of the monthly general meeting held on 21st October and 18th November, 1970, as published in the Journal'. Agreed. MEMBERSHIP THE PRESIDENT: 'I have much pleasure in announcing that the names of the undermentioned candidates, having been published in accordance with ByLaw 5.2.2, Council has elected them to membership of the Institute in the following grades: FELLOWS: Romain August Lathioor, Paolo Piga, Renato Ribacchi, Willem Frederick Jacobus Smith, Matthew Churchill, Thomas Anthony James Braithwaite, Hugh Patrick Hart, Eleanor Innocentius Muller, David Alton Smith. MEMBERS: Douglas Adendorff, Petrus Jacob du Plooy, James Valentine Grant Middleton, Karl Anders Ullerstam, Josephus Theodorus Johannes van Wyk, Frank Douglas Abbott. GRADUATES: David Mervyn Gilbart-Smith, John Philip Wilcocks Bennie, Hendrik Theunis Burger, Johann Wilhelm Coetzee, Johannes Stephanus StOols, Leon van Tonder, Brian George Harvey, John Kennedy McLean. ASSOCIATES Richard Cyril Lee Stoyell, Terrence Brian Gouws, Alister Rodney Frederick MacDonald. STUDENTS: Andries Groenewald, Christiaan Johannes Hattingh, William Hendrik Hofmeyr, Stanley Thomas Vincent. I welcome the new members to the Institute and congratulate them on their election. COLLOQUIUM The President welcomed everyone present and mentioned that this was the first of the Colloquia which are to replace the Institute's monthly meetings. He stressed that discussion at Colloquia would be completely informal and would not be recorded unless the contributor requested publication. In conclusion, he thanked the organising committee, the authors and the contributors, and introduced the author of the first paper. The following papers were presented:- 'The future development of the Iron and Steel Industry' by J. P. Coetzee (Published in the Journal March 1971). Among those who contributed to the paper were Dr Bleloch, Dr K. Gebhard, Dr Way and Professor Müller. The main point made by Dr Bleloch related to the reserves of coking coal and of coal for power generation this in country and he deduced that in South Africa we are critically short of coking coal. On the basis that 4 million tons per year of coking coal are consumed for our present steel production, over 16 million tons would be required to meet the anticipated expansion in steel output by A.D. 2000. This must be set against the grim forecast made by the Coal Advisory Board in 1967 that our national reserves of coking coal will be exhausted before A.D. 2000. This gives tremendous significance to the development work presently being carried out by Iscor on alternative methods for coke production. On the other hand the blast furnace may have to be replaced by an alternative process for the reduction of iron ores, e.g., the use of rotary kilns followed by electric arc smelting. Dr Bleloch also expressed grave forebodings about the reserves of bituminous coal, pointing out that with present methods of mining the recoverable coal in any given reserve is in general only 50 per cent of that reserve. He stated that in the past seventy years great quantities of coal have been forever placed beyond the reach of mining by being undermined by extraction of lower seams or lost by being burned. A final point made by Dr Bleloch was the fast rise in the capital investment in a fully integrated steel plant, the figure having risen in the past decade from just over R200 to R350 per ton of finished steel per annum. Dr Gebhard spoke of the direct reduction processes for iron making pointing out the difficulties of securing a high percentage of reduction and the relatively high cost of smelting in electric arc furnaces. As an alternative he suggested briquetting the high carbon sponge iron

By R. T. Muller

Contribution to the above paper by R. T. Muller (Visitor) Demands are being made and pressure is being brought to bear on employers in South Africa to narrow or eliminate the wage gap between their White and Black employees. Few thinking people will dispute the fact that a constant improvement in the wages of Black personnel is essential, but this cannot be done merely by a redistribution of income in South Africa.

Jan 7, 1974

By M. de Paiva Bueno, G. Barakos, S. Luukkanen, K. Luolavirta

Lifelong development of skills and knowledge of mining professionals has been recognised worldwide as a challenge for the development of a sustainable mining sector. Practical training and learning over the mine value chain are among the key components of this knowledge building. However, the number of available mining sites for continuous education in real-life conditions is limited; also the specifications for practical training are not clearly defined. The project MINETRAIN was developed to (i) evaluate the potential of the shortly-closing Pyhäsalmi Mine, in Finland, as an educational and training underground facility, and thus, prolong the utility of the existing modern mine site, and to (ii) develop and test practical training programs for mining and mining industry related professionals. Pyhäsalmi facilities enable training among all disciplines related to the overall mine value chain and hence, the project has potential in providing education for sustainable management of any phase of mining operations. The philosophy underpinning the MINETRAIN approach to mining activities is to assist the clients in minimising the technical and financial risks by providing a competitive and skilled personnel asset while optimising the value drivers in their operations. As a first major step of the project, a pilot training course, involving basic-level online theory and hands-on training at the Pyhäsalmi mine site, was undertaken in summer 2019. Feedback from the pilot test group of mining professionals has proved to be very positive. The comments from the participants strongly emphasised the added value of the practical onsite training for improved understanding in the large scale picture of mining on the entire value chain. As a second phase of the project, a new test course was launched in June 2020. The second MINETRAIN course focuses on new technologies and digitisation in mining. Keywords: Lifelong learning, mining education, mine value chain, research and education mine, educational research project

Jan 1, 2020

By D. W. Dean, J. A. Ryder

"A computer system designed to assist in maintenance scheduling and costing, and in monitoring the performance of equipment, is described. The emphasis is on the information retrieval and implementation aspects of the system.INTRODUCTIONThe cost of the maintenance of equipment can account for a substantial proportion of the total costs of any large industry. These costs are made up of the following elements:(i) capital expenditure,(ii) maintenance labour,(iii) maintenance spares,(iv) maintenance overheads,(v) production losses.Control of these cost elements cannot be achieved without a system which maintains and retrieves the necessary infor¬mation efficiently.The system should provide engineering management with the information necessary to:(i) establish the cost of maintaining items of equipment,(ii)establish the economic life of equipment,(iii) determine breakdown patterns for the establishment of optimum inspection, service and overhaul frequencies,(iv) establish work schedules for those responsible for the maintenance of equipment,(v) establish the optimum maintenance labour complement,(vi) establish the optimum stockholding of maintenance stores items,(vii) improve the performance of equipment,(viii) justify the selection of a particular type and make of equipment,(ix) establish the reasons for any abnormal usage of materials and labour, and to(x)reduce the dependence on the human element for the control of equipment maintenance activities.Many industries have comprehensive and numerous equipment maintenance records but they experience great difficulty in retrieving the required information in the time available and with the labour available. Many industries do not bother to maintain meaningful records, because of this difficulty."

Jan 1, 2014

By M. H. Kirchner

Trackless mining at Thabazimbi Mine by M. H. KIRCHNER*. Pr. Eng.. B.Sc.. B.Sc. (Elec. Eng.}(Stellenbosch). Dip. Mining (Pta.) Certain aspects ?f the' methods used in the exploitation, by sub-level caving, of a wide, tabular, steeply dipping orebody are described, reference being made to the use of modern mechanized equipment. Statistics relating to production and labour, as well as some geological details, are given.

By M. H. Kirchner

Trackless mining at Thabazimbi Mine by M. H. KIRCHNER. Pr. Eng.. B.Sc.. B.Sc. (Elec. Eng.)(Stellenbosch). Dip. Mining (Pta.) Certain aspects of the' methods used in the exploitation, by sub-level caving, of a wide, tabular, steeply dipping orebody are described, reference being made to the use of modern mechanized equipment. Statistics relating to production and labour, as well as some geological details, are given.

By J. G. Goodey, G. J. van der Linde

This paper describes pilot-plant tests on the recovery of apatite from a hitherto untapped material. This materialhydro- separator overflow-is very fine (80 per cent smaller than 45 µm and 32 per cent smaller than 10 µm). . The pilot-plant tests proved that the recovery of apatite from this material is economically and technically viable. This was confirmed by plant trials, which, in the early stages, produced concentrate assaying 36,6 per cent P2O5 at a recovery of 65,5 per cent.

Jan 1, 1983

By M. J. Nicol, R. P. Colborn

An investigation into the kinetics and mechanism of the oxidation of iron (11) by oxygen in aqueous chloride solutions By R. P. COLBORN Pr. Eng., Ph.D. (Natal) and M. J. NICOLt B.Sc. Hons., Ph.D. (Rand) A reaction mechanism for the oxidation of ferrous chloride by molecular oxygen is developed. and the appropriate constants are evaluated. The effect of a number of cations and anions on the rate of oxidation has been tested.

By A. Rödfalk, P. Bloemer, J. P. Nilsson, N. Brogden

"Reliable and accurate metal transfer information during silicon tapping from an EAF is invaluable for decision-making and process optimization, while obtaining such information safely is a necessity.Elkem Thamshavn Norway, a producer of metallurgical-grade silicon, identified inherent safety problems with gauging fill levels in ladles using dip bars while molten metal was continuously pouring from a rotating EAF. Operator safety was a paramount concern, and an alternative automatic method of controlling the tapped fill level needed to be found.It was also considered that further benefits could be achieved such as monitoring the tapping flow from the EAF in order to identify any clogging, as well as the potential to use the live feed from such a system to assist decision-making regarding work around the taphole area.Agellis Group AB, Sweden, a company with over 30 years of experience in gauging molten metal levels in the metals industry, was able to design a solution for Elkem Thamshavn that would provide the required real-time process data while enhancing operator safety.This paper shows how the Agellis AB EMLI-L system was successfully installed at Elkem Thamshavn’s EAF continuous tapping area, how ladle fill levels were constantly monitored, and how full ladles were replaced by empty ones without the need for operators to be in the tapping area to take level readings. The results were used to compare the accuracy and reliability of Elkem Thamshavn’s current measuring methods with that of the EMLI-L system. The paper also covers how problems such as how to connect, run, and protect cables in and around the EAF tapping area, as well as connector and cabling survivability during the three day refractory pre-bake period, were solved. Finally, the paper discusses the potential production improvements, maintenance requirements, and data integration attainable through the installation of the system, as well as the major safety improvements that have been achieved."

Jan 1, 2014

By J. L. Havenga, L. J. van der Walt, J. T. Nel

"SynopsisThe development of plasma technology at Necsa started in the early 1980s, when the applicability of high-temperature plasmas in the nuclear fuel cycle was investigated. Since 1995, this plasma expertise has expanded to other industrial applications, for example mineral beneficiation, nanotechnology, fluorocarbon production and waste treatment, all of which are also of relevance to the nuclear industry.Necsa has demonstrated the manufacture of plasma-dissociated zircon, zirconium metal powder, carbon nanotubes, silicon carbide (SiC), zirconium carbide (ZrC) and boron carbide (B4C) at the laboratory and pilot plant scale. These materials are commonly used in the nuclear industry. Zirconium alloys are used as fuel cladding material for nuclear fuel assemblies.Necsa manufactured the monomer tetrafluoroethylene (TFE), using 150 and 450 kW DC plasma systems, from which the polymer polytetrafluoroethylene (PTFE) was synthesized for use in filters and as seals in nuclear plants. With the nuclear renaissance at hand, it was demonstrated that plasma technology can be used to produce hydrofluoric acid (HF), which is used in the manufacture of fluorine gas (F2) for the production of uranium hexafluoride (UF6) directly from the mineral calcium fluoride (CaF2) without the use of sulphuric acid as in the conventional process. The recovery of valuable uranium from nuclear waste such as filters, oils, and solids with plasma processes will also be discussed. The destruction of low-level nuclear waste by a plasma gasification system can reduce the volume of this waste by several orders in magnitude, resulting in huge savings in the storage costs. Another product of plasma technology is the encapsulation process for nuclear waste and the production of vitrified product, which could be used as filler material for medium-level nuclear waste.IntroductionDuring the 1980s, a plasma research and development programme was launched at the erstwhile Uranium Enrichment Corporation of South Africa (UCOR) at Valindaba outside Pretoria. The main purpose of this programme was to develop alternative and more economical processes for the processing and manufacturing of uranium compounds used in the nuclear fuel cycle. The conversion of UO2 (as received from uranium mines) to UF6, which is needed for enrichment, conventionally involves several laborious, expensive, chemical processing steps. Plasma processes can eliminate several of the intermediate steps. Enriched UF6 is converted to UO2, which is pressed into pellets that are used in nuclear power plants. Plasma technology could also be used in a modified and optimized conversion process."

Jan 1, 2015

By A. V. Z. Brink

This paper describes the development of a monitoring architecture that allows for continuous monitoring of the process of mining, the underground environment, the state of the rockmass and its response to mining. The system is based on an open standard and is non-propriety. It allows for dense sensor arrays in the workplace, wire less communication to the closest power line, and TCP/IP communication to a central server. Continuous monitoring and quantification of the appropriate parameters allows a mine to optimise its mine process; to dynamically access the safety and health risk to people and equipment; and to quantify exposure to potential heath hazards such as dust, gas or noise. Current application examples of continuous monitoring include an application to optimise drilling and blasting thought fragmentation monitoring; an application of wireless sensor network-based monitoring in to provide early detection of potential rockfalls; and a trail to continuously assess the gold grade at the shaft through correlation with radioactivity. It is unlikely that a single monitored parameter will provide adequate knowledge of the assessed risk or even an optimisation approach. Multiple parameters are being combined using cognitive science tools such as Bayesian theory and other statistical methods to improve the accuracy and relevance of, for example, risk quantification. The decision maker is not confronted with massive amounts of raw data but rather with a single knowledge statement such a probability of failure, a human physiological strain index or an optimisation index.

Jan 1, 2008