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By Richard F. Link, Jr. Koch

"A mathematical simulation model has been devised to guide the layout of surface or underground mine workings, drill stations, and drill holes that are established in order to search for tabular ore bodies. The ore bodies may be contained within veins, sedimentary beds (including reefs), or other tabular structures.Programmed for a time-shared digital computer, the model contains both stochastic and deterministic variables. Stochastic or natural variables include the number of ore shoots and their sizes, orientations, locations and values. Deterministic or controllable variables include (i) locations and costs of workings (for underground exploration); (ii) drill station locations and costs; and (iii) drill hole azimuths, inclinations, lengths and deflections (if any).For various assumptions about the natural variables, the model is run while the controllable variables arc changed deliberately. Thus, layouts are devised to determine the percentages of the total number of assumed ore shoots found at different costs. In order to choose among the various layouts, cost-effectiveness measures are calculated."

Jan 1, 2014

By G. van den Berg

Anglo Platinum has initiated a project to investigate hydraulic hoisting technology for platinum mines. Hydraulic hoisting systems are categorized as pumping, fluidizing feeder or displacement feeder systems. Positive displacement piston diaphragm pumps are most suitable for pumping systems but they require that the ore be milled prior to pumping. Fluidizing feeders are unsuitable for platinum ore applications due to the large percentage of fines in the ore. The three-chamber pipe displacement feeder has been most widely used for hydraulic hoisting and is the most suitable technology for platinum mines. Eight hydraulic hoisting applications covering pumping and displacement feeder technologies are reviewed. The key factors to be assessed in selecting a hydraulic hoisting system for a platinum mine are discussed. A typical platinum mine configuration will comprise an ore preparation plant (to produce -15 mm material through screening or crushing), motive water pump on surface, high pressure water pipeline from surface to underground, ore slurrification plant, three-chamber displacement feeder, and a high pressure slurry pipeline to surface. The water and slurry pipelines are housed in a purpose drilled borehole. A hydraulic hoisting system selection chart is presented. A 150 mm diameter system with a 25 MPa pressure rating is required to hoist 60 000 t/m from a depth of 1 200 m. Generic capital and operating costs are presented . A major potential advantage of hydraulic hoisting is that the fines, which contain a high percentage of PGMs, are captured underground and transported directly to the concentrator. Hydraulic hoisting technology is ideally suited to providing supplementary hoisting capacity to existing shafts that have reached the skip hoisting capacity limit. The main advantage for new shafts is the potential to significantly simplify underground rock handling and transportation. All hydraulic hoisting system components are proven. The only risk area is the wear rates of the valves and piping. Current estimates are based on gold ore. The business cases investigated show that the financial viability of the installations are not sensitive to wear rate. Hydraulic hoisting is technically feasible and financially attractive for platinum mines. Keywords: Hydraulic hoisting, slurry

Jan 1, 2004

By R. Guest

Reichert cone concentrators are used successfully in many applications, but have as yet not found favour in the gold mining industry on the Witwatersrand, because, for optimum operation, the cones need to have specially designed feed-preparation and circuit details. In addition, good liberation of the valuable minerals is essential. Gravity tests, in which a pilot plant was used on refractory gold ore, showed that 94 per cent of the gold could be extracted after gravity concentration and preferential grinding, roasting, and cyanidation of the concentrate, whereas 96 per cent could be extracted by flotation followed by the same preferential treatment. However, the capital and operating costs for gravity separation are expected to be considerably lower than those for flotation.

Jan 1, 1982

By G. S. Bartlett

The theme of this Colloquium, survival strategies, not only conveys a sense of urgency but also takes cognizance of the fact that, as in the political arena, tough decisions have to be made and acted upon in the years to come. It is therefore appropriate that the SAIMM, as spokesman for the metallurgical industry, should be dealing with these issues at this time, and I wish to commend the organizers of this Colloquium for focusing on a mater as important as the future of this great industry. In view of this, I regard it as an honour and privilege to officiate on this occasion, where the best of South Africa's brain power in the metallurgical field will be harnessed with a view to moulding strategies for survival.

Jan 1, 1993

By A. J. Jager, D. P. Roberts

The stoping of platinum orebodies in the Bushveld has in the past been accomplished by using in-stope pillars to ensure stability of the workings. In the future, the use of continuous mining machines to mine the platinum orebodies is probable. It is not envisaged that such machines will cut in-stope pillars. This paper describes the alternative support systems that will replace the pillars and the stope geometries that will be required for this type of mining. The paper describes how the support resistance provided by in-stope pillars in current mining was determined and then evaluates support systems that can substitute for these pillars. Conceptual layouts based on existing breast mining layouts are presented. The layouts consist of panels of up to 100 m face length between rigid strike stabilizing pillars. A number of design charts are then proposed that allow for the design of appropriate support systems.

Jan 1, 2004

By G. R. Sawyer

Although backfilling has been in operation for many years, the methods for selecting appropriate slurry dewatering aids have, in some cases, been rather unsophisticated. This has led to many misconceptions regarding the role of the dewatering aid and its various means of application. Testing procedures employed in the correct selection of any practically applied dewatering aid must mirror the actual working processes in which they are to be used. This constraint necessitates the development of complex testing methods when applied to backfilling. The current testing procedures were scrutinized and their various merits noted. From this study a series of testing methods was evolved which incorporate the best aspects of these testing procedures with novel ideas which would eventually result in the correct selection of the dewatering aid. A major consideration in the application of any of these methods is the modus operandi of the backfilling process, and the relevance of the tests to the process. This work attempts to consolidate the testwork performed in the past and suggest new approaches in the correct selection of acceptable dewatering aids for backfilling.

Jan 1, 1988

By L. Andrews

Mineralogy, traditionally associated with concentrator studies, is being increasingly applied to problems in pyrometallurgy. Such investigations commonly make use of a number of techniques, and the results are combined for a meaningful interpretation, which can lead to a successful solution for the problem. Mineralogical techniques are described for various pyrometallurgical operations. Examples are given of studies and investigations involving mineralogy in chemical-looping combustion, feed monitoring to platinum-smelting furnaces, and losses to slag in base metal and platinum smelting.

Jan 1, 2011

By U. Kumar

Product designed characteristics like reliability and maintainability affect maintenance cost, service performance, and therefore product support strategy must be defined during design stage in terms of these two dimensions. Furthermore product support and service delivery strategy has considerable influence on the total life cycle cost and the economic viability of industrial systems/products. he paper presents a concept for the development of service delivery strategy for industrial products with a special reference to mining systems. In this paper we emphasize that the strategy for product support should not be centred only on ‘product’ but it should also take into account the service delivery capability of the manufacturers/suppliers and users service organization, users competence and capability, product use location, logistics and infrastructures, etc., to arrive at the best performance and economic results. Such strategy should invariably include services supporting the client apart from considering services supporting the product. The discussion in the paper is based on the experiences from the manufacturing industry engaged in manufacturing of mining systems and the observed trends in technology and management of operation and maintenance of mining systems. Keywords: Maintenance and product support, Service supporting client, Service delivery strategy, Products reliability and maintainability, Product use location, Operating environment, etc.

Jan 1, 2003

INTRODUCTION The SAIMM publishes technical information on various aspects of the minerals industry through several different media. (a) Monograph Series Books in the Monograph Series are high quality, detailed discussions on specialized topics. (b) Symposium Series This series consists of the proceedings of international conferences which are held in South Africa. (c) Special Publications Series This series covers titles which do not form part of the Monograph and Symposium Series. (d) The SAIMM Journal Papers published in the Journal cover al relevant areas of technical interest by striving for a balanced content and maintaining a consistently high technical standard. (e) School and Colloquia Notes The papers from al local schools and colloquia are published and handed out at registration. Should authors wish to have their papers considered for publication in the Journal, they should adhere to the guidelines outlined below.

Jan 1, 1991

The Mineral Sector Development Project, sponsored by the World Bank, has been set up to revise the legal, regulatory and fiscal framework for the minerals industry in Tanzania, with a view to attracting mining companies and investors to the country and facilitating future minerals development. One component of this project, the Environmental Management Framework for the Mineral Sector, was awarded to Wardell Armstrong of the UK and ENV Consult of Tanzania. In developing a new framework of environmental regulations, emphasis was placed on developing realistic standards which reflect local conditions and prevailing values. The main corner-stones of this approach are; effective environmental impact assessment procedures; establishment of environmental management procedures; and monitoring and auditing of companies? performance. The favoured approach involves a three-tier framework, as follows: ?Framework environmental provisions within the new Mining Act; ?Regulations covering more detailed environmental requirements ?Guidelines and/or Codes of Practice, which may in future become regulations in their own right. Careful consideration has been given, in developing the framework, to the limited resources likely to be available for implementation to the Ministry of Energy and Minerals and this has influenced the approach that has been adopted. This paper outlines the main components of the environmental management framework and discusses some of the important issues raised by these proposals.

Jan 1, 1998

By D. J. van Niekerk

Caring for the Earth: South Africa-A strategy sustainable living, by John Yeld. Southern Foundation in partnership with the World Union. Soft cover. Tel.: (02231) 72801.

Jan 1, 1993

By D. P. Roberts

The stoping of platinum orebodies in the Bushveld has in the past been accomplished by using in-stope pillars to ensure stability of the workings. In the future, the use of continuous mining machines to mine the platinum orebodies is probable. It is not envisaged that such machines will cut in-stope pillars. This paper describes the alternative support systems that will replace the pillars and the stope geometries that will be required for this type of mining. The paper describes how the support resistance provided by in-stope pillars in current mining was determined and then evaluates support systems that can substitute for these pillars. Conceptual layouts based on existing breast mining layouts are presented. The layouts consist of panels of up to 100 m face length between rigid strike stabilizing pillars. A number of design charts are then proposed that allow for the design of appropriate support systems.

Jan 1, 2005

By C. S. Chenga

Sustainable development is currently an extremely relevant concept worldwide, especially in developing countries like South Africa. Mining and metals companies are also directly affected by the sustainable development agenda. The Mining Charter?s requirements as well as new legislation (Mineral and Petroleum Resources Development Act) expect, among others, for mines to support infrastructure and poverty eradication projects in the communities surrounding the mines. The aim of this paper is to, against the background of a qualitative study of mining communities in the North-West Province of South Africa, put forward some critical factors for the sustainability of social development projects in the mining sector.

Jan 1, 2006

By M. Mpofu, M. van Schoor, T. Kgarume, H. Grobler

The South African mining industry has committed to achieving a state of zero harm for its workforce, with a strong emphasis on worker health and safety. Among the major safety concerns are falls of ground, a leading cause of injuries and fatalities. Ground-penetrating radar, a non-destructive geophysical method, is recognised for its ability to image structures, fractures, and geological features within the rock mass. However, ground penetrating radar data is often acquired in local coordinates, posing challenges for visualisation in mine computer-aided design or three-dimensional visualisation software. This study explores the pivotal role of light detection and ranging data in transforming ground penetrating radar data from local survey coordinates to absolute mine coordinates. A comprehensive georeferencing methodology is presented, providing the stepwise progression from the initial georeferencing of ground penetrating radar data to the ultimate integration of ground penetrating radar and light detection and ranging datasets, resulting in the creation of a ground penetrating radar-light detection and ranging three-dimensional model. The proposed approach not only facilitates the integration of but also offers a practical means of visualising the integrated datasets within commonly used computer-aided design or three-dimensional visualisation software. An essential aspect of this integration is the adoption of non-proprietary data formats, specifically American Standard Code for Information Interchange text files, ensuring broader accessibility and compatibility. The potential for integrating diverse datasets to construct insightful models of the underground mining environment is illustrated. Integration of different datasets has the potential to offer a holistic understanding of the mining environment, providing essential information to decision-makers.

Jul 23, 2025

The winners of the Delfos and Atlas Copco Travel Grant for Mining Engineers were announced at a cocktail party hosted by Mr Mario Pellegrino, Managing Director of Delfos and Atlas Copco, at the Sandton Sun Hotel on Friday evening, 18th May, 1984.

Jan 1, 1984

By W. Abdellah

The purpose of this paper is to establish a qualitative method to estimate the risk level (e.g. rating and ranking) resulting from mining activity. Risk is the product of two factors: probability of failure and cost of consequences. A resultant assessment scale matrix is then used to assign a risk index value which is directly proportional to the potential for excavation instability. A case study, the No. 1 Shear East orebody at Vale?s Garson Mine in Sudbury, Ontario will be examined. A three-dimensional, elastoplastic, finite difference model (FLAC 3D) is presented for a mine development intersection situated 1.5 km below ground surface. The developed assessment scale matrix is used to estimate risk index for intersection (2981) located on 5000 level. The results are presented and categorized with respect to risk-index value, probability of instability, cost of consequence, and mining stage.

Jan 1, 2014

By V. Ross

"Bench-scale flotation tests play a major role in the geometallurgical process value chain. Despite their apparent simplicity, these tests pose pitfalls in terms of operation, as well as the interpretation and modelling of results. In this paper we highlight key aspects to consider in generating accurate and reproducible experimental results, and critically review some assumptions relating to the estimation of entrainment and froth recovery. We subsequently focus on first-order equations to model kinetics and propose a method that accounts more realistically for the decay in kinetics over the duration of a float, and the contributions of froth stability and hence mass pull. The method was applied to three case studies on platinum group metal (PGM) ores and matched or outperformed first-order, two-component models. Also, it allows for a deeper analysis of the integrity of the bench-scale flotation results. IntroductionGeometallurgy is a structured, multidisciplinary approach that integrates key data from the geological, mining, mineralogical, and metallurgical aspects of the value chain to construct spatial models of an ore deposit such that the overall economic benefit and sustainability of an operation can be optimized. Process geometallurgy is aimed primarily at enhancing metallurgical efficiency and plant throughput by the application of appropriate mining and processing strategies, as well as supporting production planning and operational strategies to reduce the impact of highly variable ores. With flotation being the dominant concentrating process in the mineral value chain, the bench-scale flotation test is an important characterization tool – a relatively cheap, simple, and rapid way to obtain key information about the ore and its amenability to economic extraction of valuable minerals. This includes the evaluation of different ore types and the implications of mineralogical composition and texture for comminution and floatability, the effect of the grinding environment on the liberation of minerals, the electrochemical environment in the pulp (Bradshaw et al., 2006), the screening of reagents to improve floatability (Ekmekci et al., 2003), and the role of hydrodynamics in the recovery of valuables and the entrainment of gangue (Amini et al., 2016; Wang et al., 2016). It is also a critical tool in auditing the performance of a flotation plant by hot floats, paving the way for concept and feasibility studies and providing essential data on kinetics for the purposes of scale-up, optimization, and simulation of flotation circuits."

Mar 1, 2019

By S. Rolseth, J. Thonstad

The traditional electrolyte for aluminium electrolysis is based on molten cryolite (Na3AlF6), acting as solvent for the raw material, alumina (Al2O3). Over the years there has been a trend to increase the content of excess aluminium fluoride (AlF3) to the cryolite-based electrolyte, in order to enhance the current efficiency of the process. In most cases one has ended up at 11?13 wt% excess AlF3because higher contents makes it difficult to control the heat balance of the process. This problem may be overcome if sensors are developed that will allow online control of electrolyte temperature and composition, and we may then see a surge towards still higher AlF3contents. In the development of new anode materials to replace the carbon anode with inert, oxygen-evolving anodes, focus is on anode corrosion, and a low electrolyte temperature is then highly desirable. While the conventional process operates at around 960°C, electrolyte temperatures as low as 750°C are being tested. This is achieved by having large excess contents of AlF3(40 wt%). The consequences of using such electrolyte compositions are discussed.

Jan 1, 2004

By S. M. Brabyn

The wear in mild steel pipelines used to convey rod-milled waste backfill was determined and then compared with that obtained using a laboratory rig designed to simulate the wear condition in slurry pipelines. The relative importance of corrosion and abrasion was investigated under various conditions of water quality and particle size distribution. The laboratory rig was then used to evaluate other possible materials of construction for backfill pipelines. A preliminary assessment of the economic viability of pipelines made of alternative materials is included.

Jan 1, 1988

By R. H. English, N. C. Joughin

The results of trials with three stope-face cleaning systems are described. Two of these systems were based on armoured chain conveyors, and the third on a reciprocating-flight conveyor. The operational elements of each system are discussed with reference to their effectiveness, and many problems are highlighted. It is concluded that the reciprocating-flight conveyor is superior, and has the potential for being developed into a system yielding a labour productivity of more than 30 m2 per worker per month and a face advance of 15 m per month working one shift a day.

Jan 1, 1979