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What is the role of The South African Institute of Mining and Metallurgy at a time when so much is developing and changing in South Africa? The minerals industry is represented through employers, employees, government, education, research, public views, and even pure political interests. The role of the Institute is to represent the mining and metallurgical profession. In this role the Institute has aligned itself with Associated Scientific and Technical Societies, the Council of Scientific Societies and the Engineering Association. The Institute is also active on the Engineering Council of South Africa.

Jan 1, 1996

By E. Pothas, P. R. Jochens, L. B. McRae, D. D. Howat

SYNOPSIS The phase equilibria, viscosities and sulphur capacities of titaniferous slags were determined in the composition range of CaO = 30 to 0 per cent, MgO = 0 to 30 per cent, SiO2 = 19.69 per cent, AI.O. = 13.12 per cent and TiO2 = 37.19 per cent. The phase equilibria were determined by high temperature microscopy, the viscosities were measured using a rotating outer cylinder viscometer and the sulphur capacities were evaluated from the results obtained by equilibrating the slag in a gas stream of CO, CO2 and SO2. The behaviour of these titaniferous slags under reducing conditions was examined. Possible use of the slags for aggregate, or slag-cement, and the possibility of extracting the TiO2 are discussed. CONTENTS INTRODUCTION PHASE EQUILIBRIA VISCOSITIES DISCUSSION OF THE PHASE EQUILlBRIA AND THE VISCOSITY VALUES EFFECT OF REDUCING CONDITIONS SULPHUR CAPACITY DISCUSSION OF THE SULPHUR CAPACITY VALUES POSSIBLE USES CONCLUSIONS ACKNOWLEDGEMENTS REFERENCES INTRODUCTION The latest phase in the exploitation of the mineral wealth of the Bushveld Igneous Complex is the erection of a plant by the Highveld Steel and Vanadium Corporation Limited near Witbank to produce steel and vanadium-rich slag from the titaniferous magnetites occurring in this rock formation. These titaniferous magnetites occur as segregations in the gabbro body and the TiO2 is mainly present within the structure of other constituent minerals but also occurs in smaller amounts as ilmenite and ulvospinel. The vanadium is thought to be present in the iron oxide phase due to isomorphous replacement of the iron. Until very recently, it was feared that the high titania content of these titaniferous magnetites would militate against their value as useful iron ores. However, the design of an integrated plant to produce both steel and vanadium-rich slag, and in which the iron-making process is conducted in submerged arc furnaces instead of in

By A. Bain

The use of plastics in the coal mining industry is making slow progress whereas these materials could make a greater contribution to safety, to a reduction of working costs and to the higher productivity of mine workers. Possibly the reluctance to experiment with the new material of our age is due to the low profit margin of coal mining. This note has been prepared to present a brief survey of what has been done in the last few years and to mention some of the investigations the author has made and is making in an attempt to develop more use of plastics in the industry. Some of the plastics used on the mines have taken their place in the industry in the same manner that they are used in everyday life while others have been introduced because there has been a need for them. New uses and applications are being developed and these are the ones that are most interesting. The plastic that is specially developed to give the maximum benefit and not the one that is a modification of some other everyday product is the next development in the field. Many manufacturers are keen to promote such investigation but are not aware of the problems the mines wish to solve and therefore it is only through management itself that this development can be carried out. This note deals with plastic material under three headings: (a) Plastic as the superior material, and briefly describes how plastic has replaced a few major items which are better when made from plastic. (b) Plastics of necessity, being a short summary of how plastics had to be introduced because of laws and conditions making it a necessity. (c) Development of new ideas, being briefly some of the ideas being developed overseas and some of the ideas being tried by the author. Plastic items in common use such as in housing, electric cables, laboratory equipment, awnings, nylon bearings, locomotive brake linings, etc. being well known are not discussed. PLASTIC AS THE SUPERIOR MATERIAL Plastic belting underground Following a fire in a belt road in England resulting in the deaths of many workers, and subsequently a fire accompanied by fatalities in a belt road in a mine in this country, a law was introduced which states that only flameproof belting is to be used underground. This ruling forced the mines to use P.V.A. belting as no other was available. This belting has non-inflammable characteristics that are superior to rubber. Due to the high tension on long-distance belts used today the need for stronger belting material called for something better than cotton and the answer to this was nylon. Nylon also has the ability to withstand dry-rot which reduces the life of a belt very quickly.

By S. O. Choi, C. Park, C. Sunwoo

Two methods of stress measurements have been executed on the surface and underground to con-struct an oil storage cavern using hydro-fracturing and overcoring method. The first measurement has been performed to make a design of the caverns before excavating and the second to confirm the stress state during excavation. Six measurements have been carried out in the hydro-fracturing test at the depths between –17.8 and 54.5m from the sea level and a single measurement in the overcoring test in a single borehole at the depth of –21m from the sea level. The ratios of the maximum horizontal to vertical stress measured using hydro-fracturing and overcoring method are 2.95 and 3.1, respectively. Also, the orientations of the maximum horizontal stress are N53E and N58E. These measurements show that both methods give almost same results and significant horizontal stresses are acting on this cavern. Deux méthodes de mesure de contrainte ont étè exécutées sur la surface de terrain et sous la terre pour construire une cavité de stockage de pétrole en utilisant l’hydro-fracturing et l’overcoring. La première mesure a étè faite pour le plan des cavités avant l’excavation et le seconde pour con-firmer l’état de contrainte durant l’excavation. Six measures ont étè faites dans le teste de l’hydro-fracturing à la profondeur entre –17.8 et 54.5m depuis l’élèvation maritime. Une seule mesure a étè faite dans le teste de l’overcoring dans une seule trou de songdage à la profondeur de –21m. Le ratios de la maximale contrainte horizontale à la contrainte verticale mesure par les deux méthodes sont 2.95 et 3.1, respectivement. Les orientations de la maximale contrainte horizontale sont N53E et N58E. Ce montre que les deux méthodes donnent presque m me résultats et la contrainte im-portante est activée sur ces cavités. Zwei Druckmessungen wurden durchgeführt auf der Erdoberfläche und im Innern von Ölspeicher-kavernen unter vergleichender Anwendung des Hydrofraktionierungs- und des Kernbohrungsver-fahrens. Die erste Messung wurde durchgeführt um einen Plan der Kavernen vor der Herstellung zu erstellen und die zweite um die Druckverhältnisse während der Bohrung zu überprüfen. Sechs Messugnen wurden mit der Hydrofraktionierungsmethode bei einer Tiefe von 17,8m und 54,5m unter dem Meeresspiegel und eine einzige Messung mit der Kernbohrungsmethode in einem Bohr-loch bei einer Tiefe von 21m unter dem Meeresspiegel vorgenommen. Das Verhältnis von maxi-malem horizontalem zu vertikalem Druck bei der Hydrofraktions- und der Kernbohrungsmedthode ist 2,95 bzw. 3,1. Die Bezugspunkte des maximalen horizontalen Drucks in beiden Verfahren sind N53E und N58E.

Jan 1, 2003

By K. Harlow

"Zircon is a naturally occurring radioactive material (NORM) and as such is subject to a variety of regulations around the world. The regulatory processes and their implementation are summarized and the key issues affecting zircon and zirconia highlighted. Having absorbed the activities of the former Zircon Minerals Committee, the strategy of the Zircon Industry Association (ZIA) is to be the ‘go-to place’ for information on these matters, and its activities in the NORM space are described. Chemical industry regulations such as REACH are spreading around the world, and the paper provides an update of their status in the key jurisdictions. As mineral sands are transported to market in oceangoing vessels, they are subject to the regulations of the International Maritime Organization, which are summarized in the paper. IntroductionFrom a global perspective, zircon is generally not found in high concentrations other than in placer and dune deposits where it has been deposited along with other heavy minerals such as ilmenite, rutile, and monazite. Such deposits have been sorted and concentrated over geological time by the action of tides, waves, and wind to form concentrated deposits of heavy minerals along old coastlines and in river beds and deltas. Consequently, zircon is mostly found in association with the principal titanium minerals ilmenite and rutile. These secondary concentrations in placer deposits provide the commercial sources of zircon.All geological materials contain natural radioactivity, although the term NORM (naturally occurring radioactive material) is mostly used for minerals and other materials with above-average uranium and thorium concentrations. Importantly, the radioactive nature of zircon has not changed, but the way in which radioactivity is viewed by regulators has, affecting the zircon industry throughout the value chain."

Jan 1, 2017

By R. E. Phillips, L. A. Cramer, R. T. Jones

Atomaer (Pty) Ltd is a technology-driven company with interests in Western Australian nickel. Atomaer (RSA) Pty Ltd is a process technology company operating in Southern Africa. It is a subsidiary of Atomaer Holdings Pty Limited (Atomaer), which has operating companies in Australia, Africa, South America, and Europe. In addition, Atomaer has substantial shareholdings in Braemore Resources Plc, a nickel company with interests in sulphide nickel projects in Western Australia and Southern Africa listed on the Alternative Investment Market of London Stock Exchange (AIM); Mintails Limited, a gold company with interests in gold operations in South Africa listed on the Australia Stock Exchange; and Brinkley Mining Plc, a uranium company with interests in Southern Africa listed on the AIM. Independence Platinum Limited (IPt) has been formed by Atomaer to undertake the commercial development and exploitation of Mintek's ConRoast technology with the strategic objective of providing independent smelting and refining facilities with lower capital and operating costs for the treatment and processing of platinum concentrates, including those with high chrome and/or nickel and/or low platinum group metal values, for the development of platinum projects by junior resource companies in South Africa. The platinum mines of South Africa have traditionally exploited the Merensky Reef of the Bushveld Complex for platinum production. However, the mining of this reef is reaching depths that require significant vertical shaft systems and costly refrigeration for access to the ore bodies at deeper levels. In the past decade, all of the platinum producers have begun to mine the UG2 reef because of its cheaper mining costs. UG2 ore usually has lower platinum group metal contents and higher chrome values. The new junior resource companies have gained access primarily to UG2 reefs. Consequently, platinum mining is becoming more UG2-based and the resulting concentrates contain high levels of chromitite. UG2 concentrates are difficult to smelt in the current six-in-line submerged arc furnaces, and this leads to increased capital and operating costs for those smelting operations. The platinum mines of South Africa produce the majority of the world's platinum metal used in automotive catalysts and jewellery. As the platinum market is forecast to grow at a healthy rate into the future, the SA producers Anglo Platinum, Impala, Lonmin, and Northam are planning to expand mining operations in the next decade. Furthermore, a number of smaller new producers who are accessing other mineral resources are entering the buoyant market and will produce platinum concentrates for purchase or toll treatment. Hence, a shortage in both smelting and refining capacities is anticipated. Further smelting and refining facilities independent of the major platinum producers will be required in South Africa by 2010. Mintek's ConRoast technology is best suited to fill the need to treat a high proportion of UG2 concentrates in a cost-effective and technically efficient manner. Atomaer base metals technology has been developed for rapid leaching of nickel and other base metals from alloy. Significant reductions in capital and operating costs are expected from the combination of the two advances in process technology compared with that installed at the existing smelters and refineries that were established over 20 years ago. Independence Platinum will be listed on AIM and the Johannesburg Stock Exchange (JSE) in 2007, and developed as an independent, vertically-integrated platinum company using its independent smelting and base metals refining facilities as a strategic platform to promote the development and mining of platinum projects by junior resource companies in South Africa through technical co-operation, strategic alliances, joint ventures, off-take, toll-refining, and marketing agreements.

Jan 1, 2006

PREFACE During the past year, considerable effort was devoted to the implementation of the strategic plan that was adopted by the SAIMM in 1986. Good progress was made in a number of areas, while in others the foundation was laid for future progress. Key Objective of the Institute The key objective of the SAIMM is as follows: To identify the needs of its members and to initiate and give effect to the means whereby the requirements for technology and scientific knowledge of the minerals and metals section of the South African economy are satisfied; and to represent and promote the interests of its members.

Jan 1, 1987

By S. K. Gilman, P. S. Marcos

There are basic areas of importance within a concentrator or mineral separation plant, which require focus to ensure acceptable recoveries, throughputs remain at an acceptable level and product grades meet specification. Professional and para-professionals within the mineral sands industry are in demand due to the booming resource sector. Added to this, new mineral sands operations are being commissioned straining the industry further. These factors have increased staff turnover and introduced many new people to the industry. It is essential these new entrants are armed with basic plant troubleshooting skills relevant to the minerals sands industry to minimize production lost through poor recoveries. Mineral sands processing does not involve highly technical or sophisticated unit processes. However, success is often slow to arise due to a lack of detailed understanding, as well as managing multiple interrelated unit processes within a plant. Fundamental background physical conditions (such as equipment loading and water quality) must be met for unit processes to be efficient. Technical management of these process plants should always include observation of these background conditions for they often provide the answer to underperformance. Examples are presented with an indication of the possible effects on recovery and product grade.

Jan 1, 2007

The Gold Medal of the Institution for Mining and Metallurgy for 1978 was awarded to Adriaan Louw at the Annual General Meeting of that Institution in London on 17th May, 1979. The award was made for distinguished services to the mining industry in South Africa.

Jan 1, 1979

Each year the South African Institute of Mining and Metallurgy offers a prize (or prizes should the entries warrant it) of up to RlOO for the best paper or dissertation on a topic appropriate to the interests of the Institute. The competition is open to all Student Members of the Institute. A Student Member who is in fulltime study at a university may submit the dissertation or thesis he has to write in part fulfilment of his university degree, provided that it is presented in a manner and on a topic suitable for publication in the journal. Entries for 1976 should reach the Institute by 31st December, 1976.

Jan 10, 1976

A prize awarded by the SAIMM for outstanding academic achievement by 4th-year and 5th-year diplomates at technikons was instituted several years ago. The Senior Vice-President, Mr J.D. Austin, accompanied by the Institute's Secretary, Mrs D. Gardner, attended a prize-awarding function in the form of a luncheon at the Hotel School of the Technikon Witwatersrand on the 25th May.

Jan 1, 1984

Minutes of meeting held at the Moth Hall, Witbank on 13th November, 1969. There were present eleven members: Mr J. Meintjes (in the chair); Messrs I. E. van Aswegen, O. T. Wright, A. W. L. Brereton, A. Bain, J. Brook, P. J. Beukes, C. H. Coxon, B. F. v.d. Merwe, A. C. Hofmeyer, G. E. Carlyon. Six Associate Members: Messrs E. J. Jackson, J. N. H. Pritchard, R. E. Powell, W. Weber, R. Smith, B. T. Hosking. One Student Member Mr M. J. de Beer. Seven visitors. The Chairman reminded members of the intended visit to Barberton. Dr Stander, Director of the National Institute for Water Research, gave an interesting talk, illustrated with slides and a short film, on the conservation and reclamation of water in South Africa. After question time, Mr Hector, Witbank Town Engineer (visitor) thanked Dr Stander. The meeting closed at 7.10 p.m.

World refrigeration expert Professor Gunter Heinrich, at the invitation of the School of Mechanical Engineering at the University of the Witwatesrand (Wits), recently addressed industry representatives in Johannesburg on alternative refrigerants.

Jan 1, 1994

By T. S. Kagogo

The factors affecting haul truck tyre performance and the effectiveness of the management system at Rossing Uranium Mine were investigated with the aim of increasing tyre performance in terms of running hours until failure. The main objectives were to identify the types of tyre failure, their causes and cost implications, and evaluate the effectiveness of the management system. A site severity survey, weight study, and TKPH studies were conducted to determine the pit conditions, and an analysis of failed tyres carried out. The results showed that tyre performance at the mine has declined from 2009 to date, and the increase in lost value amounted to R5.7 million in 2012 alone. The main cause of tyre failure is loose rocks in the pit. The present management system in the load and haul department is not effective enough due to operational constraints it is facing.

Jan 1, 2014

By A. K. K. Rompel, G. K. Chunnett

Introduction Structure appears to be of secondary importance to the Bushveld Complex when viewed from a distance. However, a closer look already reveals that large fault zones bound the Bushveld Complex. These fault zones are deep-seated crustal lineaments of continental magnitude such as the Thabazimbi-Murchison Lineament, the Johannesburg-Barberton Lineament, the Palala Fault zone and the Rustenburg fault. Furthermore, the Bushveld Complex is transected by large faults such as the Vlakfontein Fault, visible in the Pilanesberg, the Steelport Fault and the Laersdfrift Fault in the Eastern Bushveld, the Brits Graben, and a multitude of dyke generations (Figure 1). When pursuing structures on a project scale, the lack of outcrop, particularly in the western part of the Bushveld, is of no help for the exploration geologist. Consequently, the first dataset that needs to be considered is the Landsatimagery. Older Landsat TM 5 or newer Landsat ETM 7 will immediately reveal areas of outcrop for field visits, and, after further processing, indicate the geological units, in particular the platiniferous Critical and the Main Zone of the Rustenburg Layered Suite (Figure 2). Airborne magnetic surveys are the subsequent dataset necessary for any decent interpretation of the geology under the ?Black Turf? cover. Currently Anglo Platinum acquires aeromagnetic surveys with a flight height of 20 m and a line spacing of 50 m. These result in high-resolution imagery absolutely crucial for dyke delineation and dip modelling, stratigraphic layer detection, IRUP detection and possibly pothole discovery and fault delineation (Figures 3 and 4). However, the aeromagnetic surveys and the Landsat imagery reveal structures very much confined to the surface and may be hundreds of metres above the platiniferous reef horizons. This may lead to inaccuracies. When determining the underground structures for shaft sinking and mine planning, a 3D seismic survey is advisable. Too many shafts have been sunk in the Witwatersrand Basin for gold and in the Bushveld for platinum without sufficient information of the structure beneath. Recent 3D seismic surveys in the Bushveld have proven the technology and visualized the reef horizons and led to an interpretation of the underground structure (Figures 5 and 6). [ ]

Jan 1, 2004

By J. P. Garnier, T. Bhambhani, J. A. Garcia, N. Renaud

Most flotation plants use a static reagent scheme, i.e., a set combination of collectors, frothers, and modifiers. This scheme is usually developed and refined over time to deliver optimal (not necessarily the highest) performance when the major ore types are fed to the plant. However, when ore types or mineralogy coming to the plant change substantially (and this often happens as different areas of the pit(s) are mined and crushed at the same time), there are upsets in the process, typically leading to lower recoveries. Adapting to this variability is usually done only when performance drastically suffers, and the changes made may be too late and bring additional variability in performance. The premise for SmartFloat™ is that the reagent suite needs to be dynamic, adapting continuously to changes in the ore and operating conditions. Solvay has combined advanced analytics and data science techniques with its expertise in flotation reagent chemistry to systematically and automatically achieve the above, and in real time. Thus, SmartFloat™ is optimizing the reagent suite continuously, removing the additional variability created by belated human interactions resulting in a better and more stable process. In addition, this advanced approach allows for continuous improvement by identifying poor performing ore domains and improving the reagent suite using Solvay’s FM-100 approach to design appropriate solutions.

Jan 1, 2023

By T. J. Otto, C. Musingwini

"The objective of any mining company is to sustainably maximize the net present value (NPV) throughout the life-of-mine (LOM). The expected NPV over the LOM is calculated based on a mine plan, yet the actual value realized by the mining company depends greatly on the level of intertemporal execution against the mine plan. Consequently, a major key performance indicator (KPI) that is often overlooked in open pit mining, due to a greater focus on temporal KPIs, is the degree of spatial compliance to the mine plan. Such focus sometimes leads to short-term actions being detrimental to long-term plans. In this paper we describe the development and implementation of a spatial mine-to-plan compliance reconciliation approach for an open pit mine. Application to a case study open pit iron ore mine in South Africa indicated a significant improvement in the spatial mine-to-plan compliance, from 69% to 94% over a three-year period from 2014 to 2016. These results indicate that implementation of the proposed spatial mine-to-plan compliance reconciliation approach can contribute positively to improving the level of spatial execution and assists in improving the alignment between short-term, medium-term, and LOM plans.IntroductionThe objective of any mining company is to maximize the net present value (NPV) throughout the life of mine (LOM). However, this objective needs to be fulfilled in a sustainable manner that considers the needs of various stakeholders, including employees, shareholders, and local communities where the mines operate. The expected NPV is calculated using a mine plan as a basis. Mine planning broadly involves identifying a strategy to exploit the mineral resource in a way that maximizes value at an acceptable level of risk throughout the LOM (Tholana and Neingo, 2016).The mine planning process is a well-recognized component in the mining value chain of an open pit mine. Figure 1 reflects the relative position of mine planning within a typical open-pit mining value chain from the mineral resource to the market"

Mar 1, 2019

By B. S. Agbenuvor, R. Morrison, V. Jokovic, C. Antonio

Body breakage usually involves breakage of particles by compression between two surfaces or impacted against a rigid surface, with the latter of interest in this current study. This mode of breakage has been identified to be the most elementary size reduction process and the most effective breakage process in comminution devices. It has been found in the literature that the progenies produced from this form of breakage possess a residual velocity at which they move, after the breakage event. In the pursuit of efficiently utilising applied comminution energy, a laboratory-scale breakage device has been developed to deliver precise specific impact breakage using the concept of a fast-moving hammer and a slow-moving particle to effect breakage. The residual velocities of the progenies from the breakage event may be used to generate secondary breakage without further addition of energy if the particle encounters a stiff obstacle such as a steel plate at right angles to its path. To measure the extent of secondary breakage, the steel wall of the device was lined with a rubber material to suppress the second set of breakage events. The performance of the new device is analysed, based on calculated t10 values and measured residual velocities of the moving daughter particles. Testing involving anvils showed a much finer PSD and higher t10 compared to the test involving rubber lining. This finding is corroborated by the measured residual velocities of the progenies. The resulting energies calculated from the measured residual velocities of the progeny were found to be approximately 42-88% of the primary specific impact energy. This retained energy was found to be sufficient for secondary breakage. Keywords: Impact breakage, residual velocity, secondary breakage, energy utilisation

Jan 1, 2020

By H. Manurung, I. M. Bendiayasa, W. Astuti, and H. T. B. M. Petrus, F Anggara, K. C. Wanta

The leaching kinetics of cerium (Ce) and yttrium (Y) in sodium-hydroxide-digested non-magnetic coal fly ash using acetic acid were investigated. The variables analysed were pH, solid-to-liquid ratio (S/L), and temperature. The results show that cerium and yttrium's maximum recovery was 57.33% and 58.36%, respectively, under leaching temperature of 90°C for Ce and 60°C for Y at pH of 1,74 and 10 g/mL solid-liquid ratio in 240 minutes. Increasing the leaching time to more than 120 minutes did not significantly improve the results. After the magnetic separation process, the ICP-OES analysis shows a slight increase in the concentration of cerium and yttrium on nonmagnetic components. The XRD and ICP-OES analysis for the sample before and after silicate digestion shows that 40% silicate was dissolved. The calculation of apparent activation energies of leaching using the Arrhenius law for the leaching of cerium and yttrium gives 22.72 kJ/mol and 35.84 kJ/mol, respectively. The kinetic leaching model of cerium and yttrium all fit Dickinson's new shrinking core model. The calculation results show that the leaching reaction is controlled by combining interface transfer and diffusion across the product layer.

Nov 6, 2024

By Jürgen Antrekowitsch, Harald Osthof, Stefan Steinlechner

"In the case of feasibility assessments or feasibility studies, an important point of discussion is often how to calculate the capital (CAPEX) and operating expenditure (OPEX) of a plant. Generally, there is also the request to know how the CAPEX varies when the size of the plant is increased. Nowadays, many databases give an indication of specific equipment costs in relation to the production rate. These data are based on cost information from equipment suppliers and have to be continuously updated by the owner of the database. The approach presented here is a model which allows sizing of process equipment, for example a leach tank, based on process data in combination with the calculation of mechanical properties. Furthermore, it calculates the CAPEX based on construction material cost and adequate machining surcharges. Thus, a single cost model for a leach tank is adequate for both copper and other hydrometallurgical plants and stays valid with changing construction material prices. To summarize, the advantage of this model is the more versatile approach and thus the flexibility due to the inclusion of design aspects, process and mechanical engineering aspects and an updatable database. The database, which is in regard to material cost and is the basis for the cost estimation, is easily updatable from commonly accessible data. This model thus approaches the procedures of an engineering company when designing a plant and executing a cost calculation. INTRODUCTION Hydrometallurgy nowadays plays an important role in processing of primary and secondary resources. In copper metallurgy, hydrometallurgy accounts for roughly 20 % of worldwide primary production, especially in the case of oxide or low copper-containing ores. Zinc smelters changed their method of production from a pyrometallurgical-dominated concept decades ago to mainly hydrometallurgical routes today. Gold production processes using leaching, especially, have a long history without any development which would not be competitive if not based on hydrometallurgical concepts (Pawlek, 1983; Winnacker-Küchler, 2006)."

Jan 1, 2015