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By A. C. Lawrence, B. Econ, D. Com

The importance of human factors in mining productivity by A. C. Lawrence, D. Corn., B. Econ. (Member) The paper outlines some of the views on the relationship between work attitudes and performance, and examines evidence derived from relevant research done in the mining industry. It is suggested that higher productivity within any given system of mining can be attained if attention is paid to the four factors that represent the CORE of human work performance: Competence, Opportunity (or Organisation), Recognition (or Rewards), and Expectations (or Enrichment).

Jan 7, 1974

By C. L. Workman-Davies

Noise is a form of pollution arising mainly from the activities of man. One such activity is mining, in which man, as in many of his other activities, uses machinery of various kinds to achieve safe, healthy, and economic production. Trackless mining makes use of an advanced state of technology over that required In traditional mining methods. One of the advantages of the former, as distinct from any disadvantages it may have, is a reduction in noise levels, the number of people exposed to noise, and the duration of their exposure to noise. This paper briefly examines why noise is a problem and what various countries are doing about it in terms of standards, codes of practice, and regulations. It also investigates the extent to which noise is a problem in mining and how trackless mining alleviates this problem. The question is then posed as to whether South Africa is not setting too high a standard at this stage of its national development by comparison with what is being done by other, more-advanced countries.

Jan 1, 1989

By B. Strohmeier

An account is given of the use of a computer to control the performance of three ultra-high-powered electric-arc furnaces in Iscor 5 steelmaking plant at Vanderbijlpark, South Africa. Several of the reports and graphs printed by the computer are reproduced.

Jan 1, 1985

By L. Dison, J. A. Hahn, G. E. Blight

A system of artificial support for shallow mines is described, analysed, and evaluated. The system can be designed rationally to support a predetermined overburden load, and tests have shown that the design theory gives accurate predictions of strength. The support system, consisting as it does of two basic materials, reinforced granular material and reinforced cemented material, is flexible and can be varied to suit changing requirements of height and load. The system of preloading to the design load by jacking off the roof ensures that the walls are both stiff and prooftested.

Jan 1, 1982

By N. Morris

In South Africa, diamonds are mined predominantly in rural areas. Kimberlitic diamonds dominate in Limpopo and the Northern Cape Provinces whereas alluvial diamonds are mainly sourced from the North West and Northern Cape Provinces. There are a few large and medium sized diamond companies (De Beers, Petra Diamonds, Trans Hex, Rockwell and Alexkor). There are many smaller companies involved in diamond mining, mostly alluvial diamond mines. The nature of alluvial diamond deposits is that they are aerially more extensive and thus their surface impacts are more pervasive: The recent downturn in diamond prices has resulted in the sudden cessation of mining at many small and medium diamond operations. The South African Mining Charter requires all mines, including diamond mines, to subscribe' to .the following empowerment objectives:

Jan 1, 2010

By J. D. Koch

The past ten years or so have seen many changes in the methods and approach adopted for projects in the metallurgical and mining industry in South Africa. These changes have led to an increased use by operating companies of the project and construction management services offered by engineering contracting companies. For a variety of reasons, this development has been slower in the metallurgical industry than in other areas of production, but that industry is also now showing an increasing trend in this direction.

Jan 1, 1981

By B. C. Alberts

Rapid and effective handling of run-of-mine, waste, and treated materials is vita.! to every step of resource development and recovery. Modern mine managements have planned and engineered systems for the handling of ever-larger tonnages. Where traditional methods have not proved to be costeffective and adequate, managements have pioneered the development of new materials-handling systems in the mining industry.

Jan 1, 1983

By G. Chisakuta, P. Bwando, G. Mitshabu

By the end of 2022, the south-eastern Copper Belt region of the Democratic Republic of Congo was host to more than 40 small, medium, and relatively large sized copper solvent extraction sites. To date, solvent extraction reagents supplied in this region have never exceeded 50% of ketoxime content. We generated laboratory extraction and strip isotherms and used these with the BASF IsocalcTM modelling software to assess the benefit of using higher ketoxime blends on the main metallurgical performance indicators such as copper recovery and net transfer. Pure ketoxime extractants combine a relatively low strip point and a decent loading capacity, which are most effective as the pH of the pregnant leach solution gets closer to 2.

Jan 1, 2023

The 8th Annual University of Cape Town (UCT)/ University of Stelenbosch (US) Minerals Processing Symposium was held at the Van Riebeeck Hotel in Gordon's Bay on 3rd August, 1990, under the auspices of the Western Cape Branch of The South African Institute of Mining and Metallurgy. The primary object of this meeting was to give research students at UCT and US the opportunity to present their work to a critical audience from industry, and to obtain feedback regarding the research needs of the minerals industry. Although the emphasis of these symposia is on work in progress at US and UCT, they also create an excellent opportunity for informal discussion between academics and metallurgists in industry. The first symposium in this series was held in 1982 at US, while the symposium in 1989 was replaced by the International Colloquium on Developments in Froth Flotation, also held in Gordon's Bay.

Jan 1, 1990

By A. N. Brown

Rock breakage by drilling and blasting is fundamental to every hard-rock mining operation. The subject was an apt choice for a mining school because many technological changes have taken place since the subject was last presented some ten years ago. However, because of the development of surface mining, it was decided that two schools should be held: one for underground mining, and the other for surface mining. The School on Underground Mining was held at the University of the Witwatersrand in February 1986.Copper 87 COPPER 87 is an international conference organized by metallurgical and academic institutions of two of the largest producers of copper in the world, Chile and Canada.

Jan 1, 1986

By N. B. Strydom

The data on heat stroke cases reported during the past five years were examined to determine the influence of age on the incidence of heat stroke. Relating the age distribution of these cases to that of the total number of Bantu mine workers showed clearly that the older men run a significantly higher risk of developing heat stroke than the younger men. Although the number of Bantu over 40 years of age in the industry is less than 10 per cent of the total they nevertheless accounted for 50 per cent of the fatal heat stroke and 25 per cent of the nonfatal heat stroke cases during the period under review. Age must, therefore, be recognised as a causal factor in heat stroke and the worker over 40 years of age should be allocated to work on surface, or in cool areas or to non-strenuous and supervisory tasks in hot areas.

The most important event in the Institute's recent history is the strategic plan, which was drawn up in 1986 during Henry James's term of office. This plan was formulated at a workshop attended by most of the senior members of Council, and from it has flowed a number of changes that have been introduced over the past four years.

Jan 1, 1990

By A. Lebedev

Application of dynamic simulation for a base metal processing plant is discussed. The plant receives ore of variable quality from two pits and blending had to be applied to maximise recovery. The plant employs multiple stage crushing, screening, dense media separation, two-stage milling, flotation and further filtration. Stockpiles and bunkers are used in the plant to cater for breakdowns and operating delays, the latter being appropriately incorporated in the model. A detail dynamic simulation model was constructed from the rock face to the filtration plant to assist the plant design, notably with definition of the ore blending method, sizing storage capacity and in-plant conveyors. The plant model was broken down to capital equipment items and various feed types and mass balances were tested to ensure that the production target is met. The dynamic simulation tested the proposed blending method, identified bottlenecks, produced risk profiles for all strategic storage facilities and overall helped minimise the project risks and improve confidence in the plant design. Keywords: Dynamic simulation, ore grade, blending, capacity, risk profile, throughput, utilisation

Jan 1, 2020

By N. V. Moraka

In dealing with transformational aspects, the South African Constitution aspires for a balance between attempts to broadly represent the country’s demographics in the way in which organizations are structured and the need to maintain the necessary skills to ensure continual retention of skills for optimum and efficient organizational performance. Through the Mining Charter, government aimed to redress gender and racial imbalances in the mining industry as part of transforming the demographic representation of mining companies to include black people, women, and people living with disabilities in all job levels up to top management. While the Constitution calls for an appropriate balance between demographic representation and competency, this aspiration for mining poses challenges for companies due to the proficient and competent skills needed in this industry. To this end, the South African mining industry has been subjected to substantial criticism from government regarding the slow progress of transformation. The mining industry justifies its slow pace of transformation by pointing at inconsistent, varying legislation and definitions governing transformation, limited skills available from historically disadvantaged groups, and cautioning not to compromise the sustainability of mining companies by marginalizing white males and white youth with the objective of addressing racial imbalances. This lack of understanding between industry and the government has led to considerable confusion regarding the accountability of stakeholders in transforming the industry. This article presents the perspectives of ten mining executives on transformation in the South African mining industry. The theoretical description of transformation, as well as other mining stakeholders’ interpretations of transformation. is presented. Qualitative data from interviews with mining executives demonstrates their understanding of transformation through rich descriptions, interpretations, and implications in their contexts. The findings demonstrate that transformation in the mining industry is not simply about race and gender, but about cultural change, a change in mind-sets, embracing diversity, equalizing rights and opportunities, and attaining social justice. Moreover, transformation is clearly a gradual process. The article concludes with a recommendation for the definition of transformation to be corroborated with the views of mining executives and that of the Constitution of South Africa. This will create an overarching, simplified definition of transformation that can be accepted and interpreted by all stakeholders.

Jan 1, 2016

By Z Bagheri, E Moosavi

Identifying the exact borders of geological domains and assessing the uncertainty of these borders are crucial steps in resource estimation. This potential field method was designed to build 3D geological models from data available in geology and mineral exploration, namely the geological map and a digital terrain model, structural data, borehole data, and the geologist’s interpretations. The resource evaluation of a copper ore deposit is often performed in three steps: (i) delimitation of the boundaries of the units corresponding to the various geological formations or ore types; (ii) estimating densities; and (iii) estimation of grades within each unit. In simple cases (e.g., a series of sub-horizontal layers), the geometric model can be built using 2D geostatistical techniques (kriging or co-kriging of the elevations or thicknesses of the various horizons) which also quantify the uncertainty of the model. A 3D model of Cu grade is generated using ordinary kriging; however, the indicator kriging method is run to design a 3D model of rock types by incorporating the drilling results. Block models of geophysical and geological characteristics are included in a similar 3D mesh to investigate their relationships in copper mineralisation.

Sep 1, 2021

By N. Watson

Historically the insurance industry's involvement in any project has been relatively late in the process. Often it was a case of the last item to be ticked off the checklist has been to ensure that the insurance is in place. However, in more recent times insurers have imposed more restrictions on the cover they are prepared to provide, which has in some cases necessitated a change in the contracting structure to accommodate the insurance policy(ies). In addition, changing contractual practices have changed the allocation of risk between the various parties involved. This calls for a more proactive approach to the design and implementation of an insurance program for both the construction and operational phases of any resource project. This paper explores how a risk managed approach to the design and implementation of an insurance program for a resource project can align itself with current management approaches to project development. From the authors' experience, this approach is best adopted early on in the project (often in conjunction with the bankable feasibility study) and follows AZ/NZS4360 to objectively examine and compare a wide range of risk exposures of the project in a time-effective manner across the following areas: ? personnel; ? environment; ? general management; ? compliance - legislation, systems, protocols; ? asset management; ? change management; ? financial impacts to the organisation; ? products/services; ? service delivery; and ? technology. Having identified and then analysed the risk exposures according to common consequence and likelihood ratings the next step is to develop a risk map of all considered exposures. The true value of this approach lies in the development and implementation of a risk treatment plan for identified exposures where the exposure is unacceptable. The plans will lead to the optimal solution to the appropriate risk prevention, risk mitigation and risk transfer options available. This paper also examines other benefits to the project that may arise from adopting a risk managed approach in addition to the ability to design an insurance program which recognises the exposures and the ability of the organisation (and other project parties) to retain risk.

Jan 1, 2007

By I. Mc Dougall

Water-cooled copper tap-hole blocks provide an effective means of extending the life of tap-hole refractories, as the lower temperature of the refractory material inhibits wear and other damage and promotes the formation of a protective frozen slag layer. This is particularly beneficial during prolonged tapping cycles. The copper block forms an integral part of the lining, and provides mechanical support to the refractory, facilitating rapid replacement of tapping channel bricks without disturbing the surrounding lining. Safety considerations are an important design factor, and the positioning of the water channels is optimized to prevent leaks although the copper is not in direct contact with the molten fluids during normal operation. Water-cooled copper blocks designed by Tenova Pyromet have successfully been utilized on metal, matte, and slag tap-holes for a number of processes, including nickel, platinum group metals, and mineral wool.

Jan 1, 2014

By M. S. Janssen, J. L. Taylor, M. A. Ford, E. B. Viljoen, H. A. Simonsen

The Stilfontein and Buffelsfontein Gold Mines, near Klerksdorp in the Transvaal, had accumulated a large amount of uranium-containing residue and, when the price of uranium rose in the 1970s, consideration was given to the possible recovery of this uranium. Preliminary tests showed that concentration of the uranium prior to leaching would not be economic. However, the pyrite in the residue could be concentrated by flotation, and the flotation concentrate could be roasted to pro¬vide both enough acid for leaching the uranium and a calcine from which the gold could be recovered. The feasibility study showed that a uranium operation of 270 kt per month would be most economically attrac¬tive, and a plant of that size was accordingly designed and built. In the first six years of its existence, the plant treated over 20 Mt of residue and produced about 3,5 kt of uranium oxide. During that time, the plant was con¬tinually being improved to make it more reliable and cost-efficient. This paper analyses the operation of the plant during its first six years from the viewpoints of its mechanical, process, and economic performance. The criteria on which the selection of the process was based are reviewed and compared with the actual performance of the plant, emphasis being placed on the leaching, solid-liquid separation, recovery, and purification stages.

Jan 1, 1987

It is widely accepted that the type of grinding media has an impact on the grinding chemistry and subsequent flotation behaviour of the sulphide minerals being separated. There are countless laboratory investigations demonstrating that inert grinding media produces more oxidizing pulp potentials, reduced levels of grinding media corrosion products, and superior concentrate grades and valuable metal recoveries. However, taking these results to industrial scale has proved difficult. This paper provides details of the protocol developed and used during a high-chrome grinding media plant trial. It describes the test regime employed to measure changes in pulp chemistry as well as concentrate grades and recoveries to produce a statistically meaningful result. The work also highlighted the need for close cooperation between the metallurgists on site and the researchers conducting the trial. To demonstrate the protocol, data gathered during a plant trail in a PGM concentrate will be presented describing the changes in pulp chemistry and metallurgical response observed.

Jan 1, 2012

By A. W. S. Schumann

G. H. HENDERSON INTRODUCTION It is a pleasure to have read Mr Schuman's wide ranging and highly informative paper and also to congratulate him. Before proceeding to give views on the use and preservation of coal in South Africa, it is perhaps apposite to look at the South African scene on the world canvas. Mr Schuman's figures in his Table I are highly revealing. The Table shows expected consumption, export and import demand in the year 1980 by the continents of the world. The Republic of South Africa is shown as one of only four exporting countries at that date, although in the interim, Australia has become an exporter and will continue to grow as an exporter of coal. Huge fields have been proved in recent years. There is reason to think that for some years, coal and its economical uses have been under-estimated. The importation of oil carries a constant question mark and the exciting possibilities expressed in the uses of Dranium a decade ago for power generation, appear to have met with some setback. Present indications are that breederreactors will be delayed until about 1990. The capital cost of such reactors, too, is enormous. By 1980 it has been estimated that 20 per cent of the energy required by the leading ten nations of the world will come from nuclear power, but 80 per cent would then remain for fossil fuels and hydro generation. COAL DEMAND AND USAGE It is of interest to record that coal production in all the countries of Europe has declined markedly in the last 25 years. This is due to competition from oil, gas and nuclear power and also for sociological reasons; but there are signs that efforts will be made to resuscitate, at least in some measure, the mining of coking coals for which there is a strong and growing demand. Possibly all hard coal now mined in Germany has coking properties and that country is self-sufficient in this commodity. Germany might perhaps consider selling coking coal to her neighbours and importing additional coal for power-raising purposes. It has been frequently stated in American publications that the coal reserves of the D.S.A. are sufficient for 1 000 years. What that means, I do not know, but it is at least an indication that America has huge reserves of coal. Domestic and export demand in the U.S.A. in 1968 exceeded production for the first time. In 1969, the United States' output amounted to some 556 million tons, an increase of less than 2 per cent on the previous year. The output achieved fell short of demand, domestic and export, by more than 7 000 000 tons. This has caused and is continuing to cause anxiety in the U.S.A. In many countries young men for a number of reasons, largely environmental and social, are not coming forward in sufficient numbers for mining requirements and the same pattern has revealed itself in the Republic. This is, indeed, alarming because mining men in large numbers will be required to meet the estimated tonnage requirements set out in the following Table: It is difficult to visualise the replacement of these coal requirements either by oil or by nuclear fuels. The coal must be mined and men are required for the purpose. Unless a greater section of the population is allowed to participate in the more responsible aspects of mining, there is a serious likelihood that demand will not be matched by output. In addition to local demand, a lively export trade is possible. Exports are dependent on the future capacity of the South African Railways and Harbours and on Government policy. An export figure of 10000000 tons per year during the decade can be visualised and this figure would raise total estimated sales production to a figure of over 100 000 000 tons in 1980. At this point, it is necessary to examine the desirability or otherwise of exporting coal. How much coal

Jan 11, 1970