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By A. Ahmed, A. Fathy, M. Eissa, K. El-Fawakhry, A. El-Mohammady

Silicomanganese is widely used as a complex reducer and an alloying addition in the production of various grades of steel due to its economic and metallurgical advantages. It is also used as a semi-product in the manufacture of medium- and low-carbon ferromanganese and metallic manganese. Manganese-rich slag, resulting from high carbon ferromanganese production, has the advantages of high manganese content, high Mn/Fe ratio, low excess oxygen, low phosphorus content, low fine content and low cost. Such slag seems to be very attractive to use as raw materials for the production of silicomanganese alloys. In the present study, experimental heats were designed and carried out to optimise the factors affecting the production process of silicomanganese using manganese rich slag in the charge. The results of pilot plant experimental heats showed that the optimum metallic yield and recoveries of manganese and silicon are obtained with initial slag basicity,(CaO + MgO) / (Al2O3), equals 1.8 by using dolomite as fluxing material and charging quartzite and fluorspar in percentage of 25% and 4% of the blend, respectively. The results showed also that an amount of 30% of coke in excess of the stoichiometric amount should be added. These result are relative for the specific high Al2O3 ores used.

Jan 1, 2004

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

Jan 1, 1996

This paper presents an initial investigation into the viability of co-kriging the grades of multiple mining cuts in a two dimensional, thin reef scenario. Deposits with gradational mineralized zones, in the perpendicular sense, are not as well served by the use of reef accumulation and thickness as deposits characterized by a sharp distinction between ore and waste rock. South African Bushveld Complex platinum deposits and Witwatersrand gold deposits are examples of this distinction. The calculation of an optimal mining cut is of paramount importance in the mining of Bushveld platinum. Two-dimensional kriging of a constant stoping width mining cut is an effective method for resource calculations once a cut is decided, but this begs the question of how to decide on the cut. Comparison of multiple cuts is used as a way of achieving this decision on many of Anglo Platinum’s operations. Although the kriging of each cut is valid in isolation, occasional negative values occur when incremental grades between overlapping cuts are calculated. Negative incremental grades cannot reflect reality. They are thought to be related to the inability of the method to include the strong continuity in the perpendicular direction demonstrated by the relevant variograms. Co-kriging of related variables has been investigated as a potential means tore impose this inherent order relationship. Various co-kriging options have been investigated. The method has been tested on a real data set from an established platinum operation. One of three types of anomaly has been investigated so far. The results show that co-kriging the mining cut grade as the primary variable, with just one secondary variable, the reef thickness, eliminates most occurrences. Severe anomalies remaining are arguably indicative of population mixing and might be more effectively treated by rezoning the data. Aim—To investigate the viability of co-kriging the grades of multiple mining cuts as a method for resolving anomalies in the estimation of such cuts on Bushveld platinum deposits, with applicability to other thin reef type deposits with a gradational not sharp cut-off between ore and waste in the direction perpendicular to the reef. Keywords: co-kriging, cross variograms, ordinary kriging, platinum, two-dimensional, grade profile

Jan 1, 2003

By Phillip J. Mackey, Rodney T. Jones

"Copper and copper alloys remain key materials for society today, with important uses found in the electrical, transportation, and construction industries. Copper demand is rising, with projections indicating that by 2025 global refined copper demand will increase to 29.5 million tons, up from the 22.4 million tons anticipated for 2015. This will require the opening up of dozens of new mines and numerous new smelters over this time period. Fortunately, Africa has significant reserves of copper, and African copper can once again play a key role in contributing to meeting the rising global demand for copper. This paper provides a brief overview of the current copper smelting operations in Southern Africa. INTRODUCTION Copper and copper alloys are essential materials for today’s modern world. The familiar green copper patina colour seen on buildings and other structures sometimes belies its true “green” characteristic – copper is essential for key emerging technologies such as wind turbines, tidal generating systems, solar energy systems, electric cars and the like. Consequently, it is believed that there will be continued growth in copper demand in the years ahead. Projections indicate that by 2025, as an example, global refined copper demand will increase to 29.5 million metric tons, up from the 22.4 million ton level anticipated for 2015. This will require dozens of new mines, and of the order of the equivalent of 10 to 12 new 0.5 million tons of copper/year-sized copper smelters (after factoring projected copper produced by electrowinning (EW))—overall, a huge undertaking. Fortunately, Africa has significant reserves of copper, and African copper can once again play a key role in supplying this rising global demand for copper. Africa’s share of global mined copper production was about 10% in 2014; however this will increase significantly in future if announced new projects eventuate. Southern Africa has an important role to play in this process. The present paper provides a brief overview of copper smelting in Southern Africa."

Jan 1, 2015

By K. P. Davey

In 1998 an initial objective was given to the author, to process valuable off grade High Carbon Ferro Manganese (FeMn) metal fines profitably. The previous attempts that had been made to re-melt these metal fines through the furnaces had resulted in poor furnace operation, mainly to do with lack of electrode penetration and furnace bed permeability. It was decided that the method to resolve these problems was to agglomerate the metal fines. During the study on the agglomeration of the metal fines, a decision was made to use furnace baghouse dust and stockpiled furnace baghouse dust and sludge (DSF) as a ?filler? in the metal fines. The primary reason for using baghouse dust was to eliminate an environmental hazard, whereas the secondary reason for using the DSF was to utilize manganese units contained in the dust. The off-grade metal fines and dust were compacted using a brick press, with cement and aluminum rich plastic clay as a binder, to obtain agglomerate that was cost effective. Through the re-melting of the agglomerated off-grade metal fines, it was realized that this agglomerate concept could have other uses, that of replacing ores on the furnace, at a lower cost. The agglomerate recipe was changed to create an agglomerate that had a high manganese to iron ratio, this replaced Comilog ore on the furnaces, thereby reducing overall furnace unit costs. Future work concerning agglomeration, is to reduce furnace costs further through agglomerating .0.5mm ultra ore fines and .0.3mm Gloria and Nchwaning sludge. Using this agglomerate replaces a portion of the Gloria and Nchwaning lumpy ore on the furnaces at a lower cost. This would eliminate problematic material that exists at the ASSMANG Manganese mines.

Jan 1, 2004

By Z. Jin, Q. Yun, C. Lu

This paper presents a quantitative assessment model for the assessment of environmental load in gold production, which is based on environmental ecology, Life-Cycle Assessment and technical conditions of gold production in China. This model can make environmental assessment in terms of a set of indexes and quantitative approach by means of artificial neural network, which also improves the theory of Life-Cycle Assessment. Keywords: Artificial neural networks, Environmental load, Assessment, Utility function, Gold production

Jan 1, 2003

The first annual student prizegiving function of the South African Institute of Mining and Metallurgy was held in the Dorothy Susskind Auditorium, University of the Witwatersrand, on Thursday, 26th May, 1977. The address (see opposite page) was given by Dr M. G. Atmore, a director of Anglo American Corporation and Vice-President of the Institute.

Jan 1, 1977

By Marko Lampi, Marc Nicolle, Janne Karonen, Kari Valkama

"In the ten years from 2003 to 2013 global mine production of copper has increased by over 23% to meet demand while the weighted average head grade has dropped from 0.9 to 0.7% Cu. These divergent trends of increasing demand and declining economic grades will extend the life of many existing mines and improve the viability of marginal and/or complex copper deposits. Against that context this paper outlines hydrometallurgical copper sulphide leaching options as alternatives to the more conventional pyrometallurgical processing route of copper sulphides. Three copper sulphide leaching and refining processes are discussed: total pressure oxidation, ferric sulphate leaching and copper chloride leaching. The effect of mineralogy on the choice of processing technology is discussed as well as some of the unit processes used. Additionally, possible benefits that a hydrometallurgical process may offer over an existing pyrometallurgical route are discussed. Subsequently, two very important aspects to the development of projects involving the leaching of copper sulphides are discussed. Finally, a number of conclusions are presented that will be useful to keep in mind when considering projects involving the leaching of copper sulphides. INTRODUCTION In the ten years from 2003 to 2013 global mine production of copper has increased by over 23% to meet demand while the weighted average head grade has dropped from 0.9 to 0.73% Cu (Murphy, 2014). If these divergent trends of increasing demand and declining economic grades continue, they will contribute to the extension in life of many existing mines and improve the viability of marginal and/or complex copper deposits. Against that context, this paper outlines hydrometallurgical copper sulphide leaching options as alternatives to the more conventional pyrometallurgical processing route for copper sulphides. Three copper sulphide leaching and refining processes are discussed: total pressure oxidation, ferric sulphate leaching and copper chloride leaching. Ferric sulphate leaching and copper chloride leaching are carried out at atmospheric pressure while total pressure oxidation takes place at elevated pressures."

Jan 1, 2015

By M. G. Wimberger

The Merensky Reef zone, as developed on Impala Platinum?s Rustenburg Operations, displays a gradational mineralized zone, with grades decreasing from the Merensky Pegmatoid Unit into the footwall and hanging wall. A system of identifying a manageable method of defining the mining cut is introduced, termed the grade profile attenuation cut-off grade. Although horizontal grade selectivity is not applied in the mining of the Merensky Reef zone, low extraction of the orebody, due to manageable and non-manageable factors, can contribute to a reduction in revenue, even losses, due to fixed cost contributions in the mining and beneficiation of the ore. A model is proposed that integrates all variables affecting the revenue of the mining operation, including the grade profile attenuation cut-off grade, the extraction factors, commodity prices and exchange rates, utilizing numerical simulation techniques in a PC-based environment. A breakeven extraction factor for a specific cut-off grade is delivered for a range of market conditions. The breakeven extraction factor is a useful guide when designing mining layouts in structurally complex and low metal content areas. Incorporating distribution functions for individual commodity prices and exchange rates into the model provides mineral resource managers with a risk profile for individual mining areas. Shaft areas have varying grade profiles and each area should have individual models run, to prevent generalizations being made about acceptable risk levels on mining areas.

Jan 1, 2004

By V. I. Zhuchkov, L. A. Smirnov, E. I. Arzamastsev, A. A. Babenko

A brief analysis is given for state-of-the-art of manganese and chromium ferroalloy production in Russia and their consumption by metallurgy plants. The main causes of low output of manganese and chromium ferroalloys, and ways to resolve the issue of ferroalloy production development are considered.

Jan 1, 2004

By Y. Poornachandra Rao, P. C. Sudhakar, L. Malakondaiah

NBV commissioned a 27.6 MVA furnace in the year 2005. This paper explains: a)Furnace design features b)Furnace process control, Direct slag granulation c)Continuous casting, Waste heat recovery, Sintering d) Gas cleaning plant, Protection of Environment. Keywords: Furnace Equipment, SiMn Production, Casting, Heat Recovery and Low hood

Jan 1, 2007

By J. -C. Tricket, W. A. Düweke, S. Kock

The high-resolution three-dimensional (3-D) seismic reflection data acquired for Impala Platinum between 1998 and 2002 in the western Bushveld Igneous Complex form an integral part of Impala?s mine planning and development programme. These data are of sufficiently high quality to provide unprecedented 3-D models of the geological structure of the Merensky Reef and UG2Chromitite Reef, from which the mine deduces the size, geometry and distribution of mineable blocks. Conversely, the seismic data details zones of un-mineable ground caused by structural disturbances in the form of potholes, fault zones and pegmatoid intrusions. Furthermore, variations in dip and strike are well imaged, allowing the mine planners to optimize the mine design and layout. Current interpretation work is focused on enhancing the accuracy of these geological model seven further through the analysis of ?seismic trace attributes.? Preliminary testing on the Impala Platinum 3-D seismic volume has shown that attribute analysis has the potential to illuminate a number of geological reef disturbances that are otherwise ?invisible? in the original seismic time volume. Potential areas of improvement include inter alia: ?Improved definition of major fault zones ?Improved definition of zones of reef depression (?slumping?) ?Identification of reef terracing and/or reverse dip.. Keywords: 3D reflection seismics; Impala Platinum Ltd; seismic attribute analysis; Seismic Micro Technology (SMT); rock solid attributes; dip-azimuth; instantaneous phase and similarity.

Jan 1, 2004

By N. A. Barcza

This publication records the proceedings of the Tenth International Ferroalloys Congress, INFACON X, and the third INFACON hosted in South Africa. The Proceedings of the previous two South African congresses in 1974 and 1992 serve, as this volume does, as a valuable record of the papers presented at these important events. This publication comes at a time in South Africa?s democratic development where the theme ?Transformation Through Technology? is very appropriate. The ferroalloy industry has played an increasingly significant role in transformation and black economic empowerment in South Africa, particularly through the advancement and sharing of technology. INFACON X plays an important role in this process, and the stakeholders and organisers of this Congress are thankful for the opportunity to hold this event at this time of transformation in our country. The world of ferroalloys, as well as that of the steel and stainless steel industries, has continued to change rapidly. Recent innovations, better use of resources, increased awareness of environmental issues and ongoing efforts to improve occupational health and safety are among the topics addressed at INFACON X and in these Proceedings. The theme of ?Transformation Through Technology? has been chosen to reflect the regional and global developments in the ferroalloy industry, and the crucial role that technology plays. The Proceedings of INFACON X, the first Congress in Southern Africa of the new millenium, represent a milestone in the technical developments in this major global industry. It contains almost eighty papers in twenty Sessions, from authors in twenty countries, covering raw materials, reductants, energy, electrodes, refractories, furnace design, post taphole services, modelling, simulation, control, sensors, fundamental issues and the applications of ferroalloys as related topics. The major ferroalloys, namely ferrochromium and ferromanganese, are covered extensively in many interesting papers. This comes as no surprise, since South Africa is the leading producer of ferrochromium and also plays a major role in the supply of manganese ore and alloys. Papers on ferronickel, silicon and ferrosilicon ensure that all the large-volume ferroalloys are addressed. These Proceedings of refereed papers of high quality will serve the ferroalloy industry for many years to come, as has been the case with previous INFACON events. For the first time in the history of INFACON, the Proceedings will be available both in bound and in a searchable electronic CD-ROM format. We appreciate the time and effort that the authors and referees have devoted to making this publication a really valuable document. Their contributions are recorded for posterity and reflect the advancements they and their colleagues have made to benefit the ferroalloy industry. Without these ongoing improvements, the industry would stagnate and not fulfil its role in the advancement of mankind. All papers included in these Proceedings were peer-reviewed by at least two referees. About 130 referees were sourced internationally to fulfill this function, and their valuable technical and editing inputs are gratefully acknowledged. Finally, I would like to thank the Technical Programme and Publication committees, led by Dr. Lloyd Nelson and Dr. Noël Machingawuta respectively. Without the tireless efforts of these individuals and their Committee members, the technical programme and these Proceedings would not have been the success they certainly are.

Jan 1, 2004

By R. Kus´

The paper presents the comments on the advantages of implementing an integrated system of managing mining exploitation in hard coal mines, as well as the comprehensive integration of information on the process of deposit exploitation with economic data, so as to achieve an optimum technical and economic effects. The principles of constructing the production management system have been presented, thanks to which the management boards are provided with reliable technical and economic information on a mining company via information technology. The strategic direction of a company’s operation may currently be verified according to the external conditions that change over time (the information on the deposit, force majeure events, changing expectations of customers, etc.).

Jan 1, 2003

By J. W. Latilla, J. J. van Wijk

A running facebreak ahead of the powered support units occurred on the number 4 seam at Matla Coal’s number 3 shaft (Matla 3) in April and May 2002.Very difficult mining conditions were experienced for a distance of some 150 m in the tailgate and to a lesser extent on the face itself. The paper analyses the main causes for the high stress conditions leading to the facebreak, namely, the existence of a >20 m dolerite sill close to surface and the effect of stopping longwalling on the overlying 5 seam. Difficulties experienced during the facebreak are discussed, including, pillar and roof collapses in the tailgate, high stress areas ahead of the face causing roof and sidewall stability problems, flushing of broken rock into the face area at the tailgate, secondary mid-face breaks, and the availability of critical support units. Successful rock engineering interventions and learning points were that, a goaf angle of 14.6° was found to be more realistic than the previously used 20 to 25° in predicting dolerite sill behaviour in this area, pre-split blasting of the sill significantly reduced stress on the face and tailgate allowing re-support work to proceed, varying pillar support types were analysed and rated, the need to always have a ground control “First Aid” kit available was recognised and a strategy for subsequent panels beneath the sill was developed. Numerous support units were used and the performance of the more suitable types is briefly discussed. A running facebreak ahead of the powered support units occurred on the number 4 seam at Matla Coal’s number 3 shaft (Matla 3) in April and May 2002.Very difficult mining conditions were experienced for a distance of some 150 m in the tailgate and to a lesser extent on the face itself. The paper analyses the main causes for the high stress conditions leading to the facebreak, namely, the existence of a >20 m dolerite sill close to surface and the effect of stopping longwalling on the overlying 5 seam. Difficulties experienced during the facebreak are discussed, including, pillar and roof collapses in the tailgate, high stress areas ahead of the face causing roof and sidewall stability problems, flushing of broken rock into the face area at the tailgate, secondary mid-face breaks, and the availability of critical support units. Successful rock engineering interventions and learning points were that, a goaf angle of 14.6° was found to be more realistic than the previously used 20 to 25° in predicting dolerite sill behaviour in this area, pre-split blasting of the sill significantly reduced stress on the face and tailgate allowing re-support work to proceed, varying pillar support types were analysed and rated, the need to always have a ground control “First Aid” kit available was recognised and a strategy for subsequent panels beneath the sill was developed. Numerous support units were used and the performance of the more suitable types is briefly discussed. Une cassure de taille en avant des unités de soutènement s’est produise sur la veine numéro 4 dans le puits numéro 3 (Matla 3) de la mine Matla Coal en avril et mai 2002. Les conditions d’extraction étaient extrêmement difficiles sur une distance d’environ 150 m dans la voie de tête et, en moindre mesure, sur le front de taille lui-même. L’étude présente analyse les raison majeures pour les conditions de grandes contraintes qui ont conduit à la cassure de taille, à savoir l’existence d’un mur de dolérite de >20m proche de la surface et l’effet d’arrêter la longue taille sur la veine 5 superposée. Les difficultés rencontrées pendant la cassure de taille sont rapportées, y compris les effondrements de piliers et toit dans la voie de tête, les aires de grandes contraintes en avant du front de taille causant des problèmes de stabilité pour le toit et les parois latérales, l’injection de roches cassées dans la taille en voie de tête, les cassures secondaires à mi-taille, et la disponibilité d’unités de soutènement critiques. Interventions minières réussies et leçons apprises furent : un angle de remblai de 14.6° était plus réaliste que celui de 20 à 25° utilisé auparavant pour prédire la conduite du mur de dolérite dans cet endroit ; tir à deux temps du mur a réduit considérablement les contraintes sur la taille et la voie de tête, ce qui a permis un travail de support complémentaire ; des types variés de support de piliers furent analysés et évalués ; la nécessité d’avoir toujours une trousse de première urgence disponible fut reconnue ; et finalement une stratégie pour les panneaux en dessous du mur fut

Jan 1, 2003

By P. K. Sahoo, C. R. Ray, S. S. Rao

This paper deals with various factors affecting the strength of chromite briquettes which plays a vital role in the smelting of charge chrome / ferro chrome production. Appropriate briquetting parameters like molasses and lime binder level, molasses quality, particle size distribution and segment condition etc. are essential to guarantee quality briquettes in the successful use of briquette and chromite ore fines. In developing a technology for briquetting of chromite ores, it is important not only to study the grain size characteristics of the chrome ore fines but also to make an informed choice of the type and quality of the binder and the condition for producing a physically and chemically competent green and cured briquette. This paper also describes the effect of strength of briquettes on various parameters of charge chrome production as the use of quality briquettes in the production of high carbon ferrochrome alloys has a number of operational, metallurgical and economic advantages. It is also a requirement for submerged arc furnace operation that the charge be adequately porous to allow gaseous products of the reduction reaction to escape from the furnace charge burden without hindrance. Otherwise, furnace material would erupt causing electrodes and furnace other equipments damage and risking the safety of the work force. The briquette, because it replaces lumpy charge but has an advantage of smaller size, allows for an uniform and porous charge so that the ascending gaseous products can escape freely. Finally this paper deals with furnace operational results with varying proportion of briquettes having same strength.

Jan 1, 2007

By A. P. I. Popoola, T. J. Olaniyi, A. A. Adeleke

"A laboratory froth flotation experiment was conducted on a low-grade carbonatite copper ore sample obtained from Phalaborwa in the Limpopo province of South Africa. The sample was a homogenous hydrocyclone overflow which serves as the feed to the flotation cells at Palabora Mining Company (PMC). The sample has an average copper assay of 0.59% with predominant copper-bearing minerals being chalcopyrite, bornite and cubanite. The carbonatite nature of the ore comes from the high content of calcium (28.85%) and magnesium (6.84%) minerals. Collectors used were sodium diethyl dithiocarbamate and potassium ethyl xanthate alongside Senfroth 38 supplied by Senmin. The results showed that at 200 g/t mixture of collectors (50:50), an optimum grade of 8.03% Cu in the rougher flotation concentrate was achieved at 74% recovery, while during the second flotation, 24.65% Cu was obtained at 74.4% recovery using a Senfroth 38 dosage of 6 L/t with 100 g/t mixed (50:50) collectors. The particle size and pH value of the pulp played a significant role in that the mixed collectors performed efficiently at pH above 8.3 and at room temperature while particle sizes greater than 53 µm were well concentrated when compared with those of less than 53 µm. INTRODUCTION The need for copper ore concentration research is on the rise as a result of the depletion of deposits and the advent of low-grade copper ores. Although most copper ore deposits have other valuable minerals that support their economic extraction, the increase in technological innovations as regards copper usage and applications has increased the demand for copper. Several factors influence concentration results in a froth flotation column, of which the reagent used is most influential."

Jan 1, 2015

By E. R. Davis, R. J. Knott

The paper discusses some of the tools of management in the field of project control, especially in engineering. Project control includes planning and cost engineering, and involves various phases: the conceptual Design and Planning Phase, the Definitive Design and Capital Budgeting Phase, and the Implementation Phase. Each of these phases is discussed in in, together with the use that can be made of data banks, progress reports, and computer systems.

Jan 1, 1982

By F. Bonnet, J. Lehmann, H. Gaye

A review of thermodynamic information and models of slags, including associated software when available, is presented. The pertinence and accuracy of these models is discussed by comparison of their predictions for various slag thermodynamic properties with the available experimental data. Practical industrial applications will be illustrated by a literature review of the dephosphorization process of ferromanganese alloys and by the description of Ti behavior during silico-manganese alloys production. This latter example will show how the thermodynamic models have been used to propose a flotation treatment at low temperature to enhance TiC removal.

Jan 1, 2004

By K. G. Philo, R. C. W. Webber-Youngman

mining, where data-driven decision making optimizes resource extraction, enhances safety, and ensures sustainability. The adoption of digital technologies like artificial intelligence (AI) and the Internet of Things has amplified the importance of digital information. However, the integrity and security of this information are paramount, leading to the exploration of blockchain technology as a potential solution for secure digital value exchange in mining. This research examines blockchain's capabilities, drawing insights from its applications in sectors like banking, government, healthcare, and entertainment, and evaluates their relevance to mining's core value chain processes. The study identifies blockchain's distributed ledger technology, cryptographic security, and decentralization as unique advantages that can revolutionize mining by enhancing transaction speed, reducing costs, and improving supply chain transparency and compliance with sustainability standards. Blockchain's transparent and auditable records can enhance business transparency, fostering trust among stakeholders, including investors and regulatory bodies. The technology's consensus mechanisms and smart contracts further promote trust in collaborative ventures. This research provides a foundational understanding for decision-makers in the mining industry to evaluate blockchain's feasibility and potential return on investment, guiding strategic planning and resource allocation for blockchain applications. By leveraging blockchain, mining companies can optimize operations, improve sustainability practices, and establish a robust foundation for future growth, positioning blockchain as a transformative technology in the sector

Jul 10, 2024