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The Institute was founded in 1894 as the Chemical and Metallurgical Society of South Africa. In 1904 it was reconstituted as the Chemical Metallurgical and Mining Society of South Africa and in 1956 it became the South African Institute of Mining and Metallurgy. The objects of the Institute are to advance the science and practice of mining and metallurgy, to afford opportunities for the interchange and recording of knowledge of mining and metallurgy and to ensure high standards of professional conduct and competence. Membership benefits include monthly issues of the Journal of the Institute, monthly General Meetings at which papers are read, symposia, excursions to mining and industrial concerns and the use of club facilities at Kelvin House. Technical journals received on an exchange basis are available to members at the Johannesburg Public Library. The current membership of the Institute is over 1,400. Membership applications are accepted from suitably qualified persons and the requirements for entrance to the various grades of membership are summarised below. Members shall be not be less than 30 years of age, shall be university graduates in pure or applied science or shall produce evidence to the satisfaction of the Council that they have successfully completed a co-ordinated course of study in pure or applied science of at least three years' duration at an approved university or institution deemed by the Council to be of equivalent status. Members shall have been employed in senior technical positions in important mining or metallurgical undertakings for at least five years or they shall have practised as mining or metallurgical consultants for at least five years. They shall be practising their profession at the time of application. Entrance fee R4.00; Annual subscription R14.00 (town), R12.00 (country). Letters of designation: M.S.A.INST.M.M. Associate Members shall be not less than 25 years of age and shall be university graduates in pure or applied science, or shall have successfully completed co-ordinated courses of study in pure or applied science of at least three years' duration. They shall have been engaged in work of an approved technical character in the mining or metallurgical industries, of which not less than two years shall have been in positions of responsibility. A candidate shall be practising his profession at the time of his application. Entrance fee R2.00; Annual subscription R12.00 (town), R10.00 (country). Letters of designation: A.M.S.INST.M.M. Affiliates shall be not less than twenty-five years of age, and shall have been engaged in positions of responsibility in, or associated with, the mining or metallurgical industries for periods of not less than three years. If, however, the candidate for admission to the higher grade of Affiliate, is at the time of his application, already a Student member, he need satisfy the Council only that he is, at the time of his application, engaged in a position of responsibility in or associated with the mining or metallurgical industries. In all cases the applicants shall satisfy the Council that they are fit and proper persons to become Affiliates. Entrance fee R2.00; Annual subscription R12.00 (town), R10.00(country). Graduate Members shall be not less than 21 years of age and shall be university graduates in pure or applied science, or have completed co-ordinated courses of study in pure or applied science of at least three years' duration at an approved university or institution. They shall not remain Graduate members after attaining the age of 30 years without the persmission of Council. Entrance fee R1.00; Annual subscription R7.00 (town), R6.00 (country). Students shall be persons not less than 18 years of age who are being educated or trained in a manner approved by the Council, to occupy a technical position in or associated with the mining or metallurgical industries and who, furthermore, shall not have attained the qualification required for a higher grade of membership. They may remain Students until they have obtained the necessary qualifications for transfer to a higher grade of membership, but not after the end of the Institute's financial year in which the attain the age of 28 (twenty-eight) years. They shall then transfer to a higher grade to retain membership of the Institute. The Council may relax the provisions of this clause in such cases as it considers appropriate. Entrance fee nil; Annual subscription R3.00 (town), R3.00 (country). Other. The Council has the power to elect to the grade of Member or Associate Member candidates who may not fulfil all the requirements for entrance to these grades but whose status, professional achievements and practical experience in mining or metallurgy justify such election. Applications. Requests for membership application forms should be addressed to the Secretary: South African Institute of Mining and Metallurgy, p.a. Box 1183, Johannesburg.

By W. K. Loftus, H. S. Simpson

Discussion I. R. M. Cheston (Visitor): I should like to congratulate the authors on this interesting paper which graphically illustrates the overall effects of the gradual developments in diamond concentrating processes which have taken place over the past few years. These final stages of diamond concentration represent only a minor factor in the cost of diamond production but because of the shortage of highly trained people for this work, any easing of the burden on the sorting staff has an importance far beyond the immediate economic sphere. The search for the solution of problems posed by the economic and social conditions of industry is never-ending. The Diamond Research Laboratory is, even now, carrying out further work to improve still more the operation of general diamond recovery processes as described in the paper. Before looking at some of the latest developments in this field of final recovery, there are a few points arising from the paper on which I would like to comment. On page 321, reference is made to the X-ray sorters originally developed by the DRL. The paper gives a figure of 100 per cent recovery of diamonds from +7 mesh concentrates in two passes through the prototype machine. Not wishing to claim miraculous powers for our group, I would prefer to see this given as virtually 100 per cent recovery of all fluorescing diamonds. Firstly however much care is taken, there is bound to be an occasional operating loss. In the test work, 100 per cent recovery was made on many occasions but this was not always so. Secondly, although most diamonds fluoresce strongly under X-rays, some diamonds only fluoresce weakly. Type IIB diamonds, in fact hardly fluoresce at all, but the incidence of this special type of diamond is very low in most deposits. However, in operating the commercial X-ray machines, there is a certain background level of reflected radiation from other feed particles. Unless the diamond fluorescence is several times greater than this, it is not possible to achieve sufficient sensitivity in ejection. A certain small but variable proportion of diamonds from each deposit is always found to fluoresce too weakly to be recovered by the X-ray machine. Tests have shown, that for the De Beers mines, this proportion is considerably less than I per cent. These diamonds are nearly all dark brown or black in colour and therefore of low value. The degree of fluorescence does not, however, depend entirely on the colour or quality of the diamond and some of the brightest fluorescence comes from the lowest quality of boart diamonds. Investigations into the property of the diamond which causes this low fluorescence are being carried out. On page 322 it is suggested that zircon fluoresces in the same colour spectrum as the diamond. This is not quite accurate. The total light given out by zircon under X-rays is of the same order as that of diamond. However the zircon radiation has a much wider spectrum band than the diamond fluorescence. Reference is also made on page 322 to the effect of selective milling in small laboratory mills on diamonds. Perfect diamonds are very hard and very strong and are extremely difficult to break. Imperfect diamonds, which form the majority of diamonds recovered from most deposits, although hard, can be very brittle. Even under slight impact some of these diamonds may shatter to powder. Milling conditions must therefore be extremely closely controlled to minimize breakage, and even so, some breakage will always occur. As suggested in the paper, the necessary conditions are: the use of small balls, slow speed mills and very limited water addition. Tests elsewhere have suggested that the water content of the pulp in such a mill must be less than 25 per cent by weight of pulp to prevent diamond breakage reaching significant proportions. The skin flotation techniques described on page 323 operate on a very small scale. It is of interest to note that in West Africa a large-scale continuous skin flotation machine is used to recover the fine diamonds. In this operation the feed is dried and, after standing, is mixed with water and fed in a single layer onto a woven phosphor-bronze conveyor belt. This belt runs at a shallow angle into a water bath and as the particles are carried through the air-water-interface, the diamonds float off and over a weir into a collecting box. The bulk of the particles, being wettable, sink to the bottom of the tank and are continuously removed. If treated without prior drying, the diamond recovery is poor. If material is treated immediately after drying, a lot of the gangue particles also float. During standing, in the hot and humid atmosphere of West Africa, it is found that the gangue particles recover their wettability much faster than the diamond particles. Optimum selectivity is obtained after standing for approximately 24 hours. At the DRL we have been experimenting with optical filters to differentiate between the fluorescence of diamonds and zircon. By limiting the light transmission to the fairly narrow range emitted by diamonds, it is

Jan 4, 1970

By R. Ajalloian, L. Karimzadeh

This paper describes the engineering properties of Givi dam foundation. Givi dam will be built across the Givi River on the andesitic rocks (Karaj formation) in Ardabil province (northeast of Iran). Geotechnical investigations including drilling, pumping tests, sampling for laboratory testing and discontinuity survey. Physical and mechanical properties of andesitic rocks such as density, water absorption, porosity, uniaxial compressive strength, triaxial compressive strength, durability and direct shear tests are evaluated in this paper. Discontinuity data are process for the determination of dominant sets and for the rock mass characterization in terms of classification systems ( RMR, Q and RSR ). Correlations between these three classifications are discussed. Le barrage doit être construit sur la rivi_re givi qui cou_e sur les andesites (formation de Karaj)dans la province d_ Ardebile situee_ a Nord- Ouest de l_ _Iran. Les études géophsique commesondage, Pompage. Et échantillonnage afin de verifier les discontinutés out éte_ effectuées. Lesproprietés physique et méchanique des roches andesifique ont éte_ verifieés. Les informations concernaüt aux discontinuitiés afin de montrer leur principale direction ont éte_ verifieés, les proprietés des roches dans leurs ensemble ont éte_ etudieés. Les divers classifications(RMR,Q,RSR ) ont éte_ comparés et analyseés. Dieses Schreiben ist zur Erklaerung der Ingenieureigenschaften ueber Baugrund des Givi Deiches.Dieser Deich soll im Givi fluss auf Andesitgesteine (Karaj formation) gebaut werden. Der platzdes Deiches legit im Ardebil Provinz nordwestlich von Iran. Geotechnische Untersuchungen Sind:Bohrungen, pumpen Versuche, Probenentnahme fuer Laborversuche, BrechbarkeitBestimmungen, physikalische und mechanische Eigenschaften der Andesitgesteine wurde hierausgewertet, wie Z.B.: Wasserleitfahigkeit, Porositaet, Scherfestigketswiderstand, Informationenueber Brechbarkeiten der Gesteine wurde gesamelt, und die meisten Brechbarkeiten bestimdamitman die Gesteine besser klassifizieren kann. In Endefekt wrid die Resultate verschiedeneKlassifizierung wie RMR, Q, und RSR besser geachtet und zusammen vergliechen.

Jan 1, 2003

By C. Musingwini

The South African platinum mining industry is using a number of different mining methods, including variations of the same method, to extract the narrow reef tabular platinum deposits of the Bushveld Complex. These mining methods fall into three broad categories, namely conventional, mechanised and hybrid mining. A question sometimes asked in the industry is whether mechanized mining methods are more efficient than conventional mining methods. An objective answer requires the methods to be evaluated against multiple criteria simultaneously, whereby each criterion has a relative degree of importance in the overall decision. The most efficient method is the one that scores highest on each criterion. However, some of the criteria can be conflicting, such as by increasing dilution the shaft head grade decreases. The analytic hierarchy process (AHP) methodology was selected for the study because it is used to solve problems of this nature. A survey was carried out to determine the relative importance of each efficiency criterion by drawing on the knowledge and experience of mine technical services and project management practitioners in the industry. Efficiency data for four different mining methods drawn from the Egerton (2004) study were used as a case study. The conventional mining method ranked as the most efficient mining method from the four methods considered. The exercise indicates potential for the AHP to be used in the South African platinum mining industry as a tool for selecting optimal layout designs, conduct regular evaluation of the performance of production shafts, or objectively evaluate line managers for promotion. The work described in this paper is part of the methodology used in a current PhD research study at the University of the Witwatersrand. Keywords: Analytic hierarchy process (AHP); multiple criteria decision analysis (MCDA); decision-making; conventional mining, hybrid mining, mechanized mining.

Jan 1, 2008

By C. Birch, M. Katuruza

"The purpose of this study was to demonstrate unmanned aircraft system (UAS) technology in opencast highwall mapping using the experience at Isibonelo Colliery in Mpumalanga Province of South Africa. In opencast mines, geological mapping has evolved over time and there have been challenges in extracting valuable information from exposed highwalls due to restricted access for safety reasons. A UAS was used at Isibonelo Colliery to conduct highwall mapping, using drone-based digital photogrammetry techniques. A demonstration survey was undertaken during February 2018. The highwall flyover demonstration was planned for two areas (North and South pits) where field control points were placed by the mine survey department. A contractor used a DJI Phantom 4 (Pro) for the highwall mapping. Raw data was processed within 48 hours and a 3D model of the mapped pit area was produced. Further data extraction included obtaining updated weathering and lithological contact elevations and thicknesses for use in short-term planning. The results showed a good correlation between the resource model and the UAS data model. The project was considered a success and highwall flyover mapping and is now standard practice at Isibonelo Colliery.IntroductionDetailed geological mapping is crucial to the understanding of the structure of any mineral deposit. Several mapping methods may be applied depending on the available exposure/outcrop and nature of the orebody; for example, coal deposits typically suboutcrop only, therefore an opencut highwall provides the best exposure for mapping the geology. Mapped information, when incorporated into a resource model (generated from exploration borehole data), improves the understanding of the orebody or coal seam. This research paper focused on the use of unmanned aircraft system (UAS) technology for pit highwall mapping to generate data for updating geological models and avail the latest information to mine planning to improve the short-term plans."

Mar 1, 2019

By T. F. Cho, B .. O. You, K. S. Yoon, K. S. Won

Discontinuity Orientation Measurement (DOM) drilling system capable of retrieving the reference line-marked core log, which can be used for determining the relative positions and orientations of discontinuity planes along the borehole axis, has been developed. Accuracy of the borehole joints data measured from the reference-lined core and, eventually, the significance and applicability of DOM drilling system for site exploration are verified by comparing with the spatial characteristics of joints investigated by implementing borehole image-taking instruments in the same borehole. Enhancement of boring efficiency has been also confirmed by performing twin drilling operations, one with DOM drilling system and the other with a conventional drilling machine equipped with D-3 core barrel, on two neighbouring sites of 5 m apart. Ein DOM(Diskontinuitätsorientierungsmessung)-Bohrsystem, das durch Grundlinien markierte Bohrprobelog extrahieren kann und die relativen Lagen und die Orientierungen der sich im Bohrloch verbreitenden Flächen bestimmen kann, ist entwickelt worden. Die Wichtigkeit des DOM-Bohrsystems und dessen Anwendbarkeit auf die Erforschung auf dem Bohrplatz werden dadurch bewiesen, dass man die Genauigkeit der Daten der Bohrlochsspalte, die durch die die Grundlinie zeichnende Bohrprobe gemessen werden, mit dem räumlichen Eigenschaften der Spalte vergleicht, die durch die Bildaufnahme des gleichen Bohrlochs nachgeforscht werden. Un system de sondage, Discontinuity Orientation Measurement (DOM), capable de récupérer des carottes markés en une ligne de référence a été dévelopé. Il peux être utilisé pour déterminer les positions relatives et les orientations des plans de discontinuité le long de l’axe de trou de sonde. Leur signification et applicabilité pour une caractérisation de site est verifiée par une comparaison de la précision des données a propos des joints mesurés a partir des carottes markés et les carac-téristigues spatiales des joints enquêtés par le camera de sondage

Jan 1, 2003

By H. M. Krieg, M. J. Ungerer, C. G. C. E. van Sittert, D. J. van der Westhuizen

"The transition metals tantalum (Ta) and niobium (Nb) are of significant importance, for example in the nuclear energy sector where they are used as cladding materials, as well as in capacitors and specialized materials. For these applications a high-purity metal is needed. The separation of Ta and Nb is always a challenge since they are found together in nature and have similar chemical and physical properties, resulting in costly and laborious separation processes. A technology that has been used successfully for the separation of these metals entails solvent extraction (SX)1. While separation was achieved in a previous SX study using a sulphuric acid (H2SO4) medium with the extractants diiso-octyl phosphinic acid (PA) and di-(2-ethylhexyl) phosphoric acid (D2EHPA), due to the absence of speciation data for Ta and Nb it is not clear how the separation occurred.One method that might be suitable for determining the speciation of a reaction is molecular modelling. Calculations based on the densityfunctional theory (DFT) are now used not only for light elements and small molecules, but also metal complexes, heavy metals, and especially metal separation in SX2. In this study the aqueous phase used during SX was investigated by studying periodic systems of Ta, as a metal and in salt form, when it is in contact with H2O and H2SO4. The results were used to predict the reaction mechanism occurring during SX. Results showed that (i) in a 1:1 acid-water ratio, the deprotonation of H2SO4 was endothermic, (ii) in a 1:5 ratio deprotonation was exothermic forming HSO4 -, and (iii) in a 1:10 ratio double deprotonation occurred to form SO42- exothermically."

Jan 1, 2017

By C. -I. Lee

Since the early 1970s, Korea has constructed many large-scale tunnels and underground storage caverns in response to the rapid industrial development. The rock mechanics engineers have accumulated valuable experiences in the area of underground space technologies. But they still face technical challenges in environmental and safety aspects. To discuss those challenges in Korea, a brief engineering description of underground space projects including oil and gas storage, food storage, pumped storage power plant, transportation tunnels, waterway tunnels, and radioactive waste disposal is presented. Mechanical and hydrological stability analyses of the storage caverns in Korea are also introduced. Depuis le début des années soixante-dix, le développement industriel rapide en Corée a entraîné la construction de nombreuses galeries et cavernes de stockage souterraines. Les ingénieurs de mécanique minière ont donc accumulé des expériences précieuses dans le domaine de la technologie de l’espace souterrain. Cependant, ils font toujours face à de nombreux défis techniques en ce qui concerne les aspects de l’environnement et de la sécurité. Pour présenter ces défis en Corée, l’étude présente décrit les projets d’espace souterrain, y compris le stockage de pétrole et de gaz, de nourriture, centrales de stockage pompé, tunnels de transport, tunnels navigables, et évacuation des déchets radioactifs. Des analyses de stabilité mécanique et hydrologique des cavernes de stockage en Corée sont aussi présentées. Seit Anfang der 70er-Jahre, baute Korea in Folge raschen Industriewachstums viele lange Tunnelsund unterirdische Lagerungsräume. Fachkräfte im Bereich Gesteinsmechanik sammeltenwertvolle Erfahrungen über unterirdische Raumtechnologien. Dennoch stehen sie auch heute nochvor technischen Herausforderungen im Bereich Umweltschutz und Sicherheit. Zur Erläuterungdieser Herausforderungen in Korea folgt eine kurze technische Beschreibung der Projekte zurSchaffung unterirdischen Raumes für beispielsweise Öl- und Gaslagerung,Nahrungsmittellagerung, Pumpspeicherwerke, Straßen- und Wasserstraßentunnels, als auchLagerung radioaktiven Mülls. Mechanische und hydrologische Stabilitätsanalysen derLagerungsräume in Korea werden ebenfalls dargestellt.

Jan 1, 2003

NOTICES PROCEEDINGS OF THE SECOND INTERNATIONAL CLEAN AIR CONGRESSThis massive volume of 1,380 pages contains all the papers presented at the congress held in December 1971. INDEX TO SOUTH AFRICAN PERIODICALS This bibliographical work has been produced by the Johannesburg Public Library since 1945, and is of interest to all our readers. THE CONTROL OF GASEOUS SULPHUR COMPOUND EMISSION An international conference on this theme will be held at the Salford University from 10th to 12th April, 1973. COLLOQUIUM ON SLlMES DAMS The South African Institute of Mining and Metallurgy have great pleasure in advising members that two-day colloquium on Slimes Dams is being arranged for the 14th and 15th November, 1973. NATIONAL INSTITUTE FOR METALLURGY / NASIONALE INSTITUUT VIR METALLURGIE REPORT. VERSLAG No. 1424 REVIEW OF THE WORLD'S FLUORSPAR INDUSTRY, WITH PARTICULAR REFERENCE. TO SOUTH AFRICA Ist August, 19n Investigator: H. H. Gossling SYNOPSIS The consumption of fluorspar has increased significantly during the last three years, and a consumption of approximately 5,76 million tonnes per annum is projected for 1975. REPORT. VERSLAG No. 1432 LABORATORY METHOD No. 44/2 THE DETERMINATION OF RUTHENIUM AND OSMIUM IN THE RESIDUES RESULTING FROM THE LEACHING OF MATTES 5th July, 19n Investigators: Magdalena M. KrUger R. V. D. Robert SYNOPSIS The method described involves the sintering of the residue with barium peroxide, and the distillation of ruthenium and osmium from the sinter. REPORT. VERSLAG No. 1439 THE REACTION OF SULPHIDE MINERALS WITH THIOL COMPOUNDS 29th June, 19n Investigator: L. A. Goold SYNOPSIS A selected group of thiol reagents was reacted with a wide range of sulphide minerals, and products that were formed at the surface were extracted and identified by infrared spectrophotometry.

Alexander Sutulov. Mineria Ghilena 1545-1975 (Mining in Chile 1545-1975). Santiago, Centre of Investigation of Mining and Metallurgy, 260 pp. (In Spanish). G. B. Rothenburg. Speciality steels. D.S.A., Noyes Data Corp., 1977. 270 pp. Witbank Middelburg Branch A General Meeting was held at the Wit bank Golf Club on 20th April, 1977, at 17h30. Treatment of waste water An International Research Symposium on New Processes of Waste Water Treatment and Recovery is to be held in London from 6th to 8th September, 1977. It NIM reports Report no. 1708 An examination of the suitability of various reducing agents for the production of ferrochromium. (27th Feb., 1975; re-issued May 1977). Report no. 1724 The preparation and reduction of chrornite pellets containing a reducing agent. (14th Apr., 1975; re-issued Mar. 1977). Report no. 1854 The interaction of pyrite, oxygen, and xanthate. (8th Mar., 1977). Report no. 1876 The ultrasonic determination of the mud level in a thickener and the resin level in an ion-exchange column. (6th May, 1977). Report no. 1878 The electrochemical dissolution of galena in aqueous solutions. (5th May, 1977). Report no. 1881 n-Octylaniline, a new extractant for noble metals.(28th Mar., 1977). Report no. 1883 The determination of iron, chromium, titanium, and tungsten by X-ray-fluorescence spectrometry. (31st Mar., 1977). Report no. 1889 Entropy relations in the formation of complexes of silver (1), mercury (II), and cadmium (II) with llwnodentate liyaruls. (5th May, 1977). Mechanics of granular materials A conference on the above subject is to be held in London on 8th and 9th September, 1977, under the auspices of the Institute of Mathematics and Its Applications.

Jan 1, 1977

O.F.S. Branch Proceedings of the Annual General Meeting Held on Wednesday, 4th August, 1976 Mr G. J. C. Young (Chairman) was in the Chair. Also present was Dr R. E. Robinson, President of the South African Institute of Mining and Metallurgy. NlM reports Report no. 175 Copper extraction by leaching magnetites from Palabora Mining Company. (12th Apr., 1967; re-issued Jun. 1976) Report no. 1632 A mineralogical examination of beach-sand concentrates from a pilot plant at Richards Bay. (20th May, 1974; re-issued Jun. 1976.) Report no. 1825 The full automation of a Philips 1220 X -ray spectrometer. A Philips 1220 X-ray spectrometer (semi-automatic) Report no. 1840 The spectrophotometric determination of total uranium in silicate ores and leach liquors by use of bromo-PADAP. Report no. 1841 The determination of aC1;d-soluble uramum in silicate ores and solutions. AS & TS National Award The Associated Scientific and Technical Societies of South Africa has decided to make two National Awards this year. These awards, given in recognition of outstanding contributions to science and the application of science, will be made to Dr T. L. Wadley for his invention of the Tellurometer system of distance measurement and to Mr H. Scheffel for his design of the High Stability Bogie. Treatment of waste water A major international symposium, organized jointly by the Water and Environment Group of the Society of Chemical Industry and the Environment Group of The Chemical Society of London, will be held in London in 1977. Down-the-hole drilling Atlas Copco announces the publication of a revised and enlarged version of one of the booklets in their series 'Mining and Construction Methods'. This 40-page booklet is entitled 'Down-the-hole drilling with COP drills'.

Jan 10, 1976

1. Book review Economics of mineral exploration in Australia, by Brian W. Mackenzie and Michel L. Bilodeau. Australian Mineral Foundation (Private Bag 97, Glenside, South Australia 5065). 198pp. $A58. $A45 for students. Reviewer: D.G. Krige 2. Recent publications Combustion of coal liquid mixtures, by G.F. Morrison. London, lEA Coal Research, 1983, 52 pp. Hafnium: physico-chemical properties of its compounds and alloys. Vienna, International Atomic Energy Agency, 1981. 408 pp. 620 Austrian schillings. Canadian mines handbook 1984-85, edited by CD. Gardiner. Toronto, The Northern Miner, 1984. 500 pp. $24. Drilling equipment in Canadian mining and exploration- opportunities for the industry, by AJ. Jakubek. Toronto, Micromedia Limited (144 Front Street, Toronto M5J IG2, Canada), 1984. Research report 1984. Port Melbourne, Division Mineral Chemistry, Commonwealth Scientific and Industrial Research Organization, 1984. 190 pp. Surface engineering Wear is an unavoidable problem in virtually all products of the engineering industry, from the minute bearings of instruments to the cutting surfaces of earth-moving plant. Safety in mines About 50 papers will be presented at the 21st International Conference of Safety in Mines Research Institutes at Sydney from 21st to 25th October, 1985. Some 250 delegates from 30 nations are expected to attend. Professional development seminars March 18th-21st, 1985 Underground Blast-hole Mining May Ist-3rd, 1985 Mineral Processing of Gold Ores May 6th-10th, 1985 Mineral Comminution Systems May 13th-15th, 1985 Processing of Metallurgical Residues Analytical chemistry The Second Symposium on Analytical Chemistry in the Mining, Exploration and Processing of Materials is to be held in Pretoria from 15th to 19th April, 1985.

Jan 1, 1985

By R. C. J. Goode, W. S. Rapson, W. R. Lawrie, L. W. P. Van Der Bosch

W. R. Lawrie (Member): As all the Institute members present are aware, the Ninth Commonwealth Mining and Metallurgical Congress was held in Great Britain from 3rd to 24th May, 1969. The Congress opened in London and the first week was devoted to technical sessions. Several receptions and other forms of entertainment were held in the evenings. The Congress was attended by some 1 200 delegates, many of whom were accompanied by their wives. As can be imagined a large organisation was needed to cater for all the whims of these delegates, to arrange accommodation and to provide transport for the technical trips, for the receptions and for the sight-seeing tours. Papers presented at the technical sessions proved of great interest. It was stimulating to hear of the developments taking place in the various branches of mining and metallurgy. The discussions which developed between men from so many different countries were thought provoking, led to new friendships and most of us made valuable contacts for the future. There were 141 papers presented in the one week. They were given in four separate halls with two, three and sometimes four papers coming up for discussion in each of the three sessions per day in each hall. Among the more interesting subjects were those concerning off-shore drilling and the facilities for production of petroleum and natural gas. Beach mining at Consolidated Diamond Mines drew a large audience. Automation, mechanization and other technical developments were well described and we were brought up to date with modern techniques of mineral prospecting. There was general discussion on the future of the mineral industries together with comments on the consumption and price trends of these metals and minerals. The future of uranium, of vital interest to us in South Africa, came in for much debate. During the first week, besides attending the technical sessions and seeing some of the sights of London, we were royally entertained. There was a banquet, attended by some I 400 people, where we were welcomed by Princess Alexandra, a reception by H.M. Government in the Banqueting House, and we were entertained at the House of Lords on a terrace overlooking the bustling and rather muddy river Thames. Then there was the visit to the Glyndebourne Opera. It is only in London that at 3 o'clock of an afternoon, nearly 1 000 people all togged up in dress suits and long dresses and carrying packets of sandwiches for supper could arrive at a station to catch a train, and not even cause a stir of interest or a raised eyebrow! This is the way we travelled 60 miles to the opera from London. Surely there can be no more picturesque or romantic a setting for an opera than this large 400-year old red brick manor house nestling in the green valleys of the unspoilt Sussex countryside. It was a glorious evening and though we returned somewhat late and tired, not one of us would have missed this experience. After the first week in London there was a choice of tours of one week to London and the Home Counties, Cornwall, a Geological tour to Scotland, South Wales, and North England. These were followed by further one week tours to Yorkshire and Lancashire, Scotland, West Country and Midlands, a Geological tour of Wales, and a Mining and Geological tour to Jurassic Iron Mines. We then returned to London for the final session and closing banquet. Post-congress tours were arranged to Europe and to Ireland. It was a wonderful Congress, a great experience, we made many friends and may there be many more congresses! . L. W. P. van den Bosch (Member): Much has already been said in appreciation of the excellent organisation and arrangements made for the delegates who attended this Congress. This report is confined to a brief discussion of the personal impressions gained from the papers presented and the technical visits attended. The papers covered a wide variety of subjects ranging from highly theoretical observations to practical descriptions of operations. There were three main themes, VIZ: 1. The attention given to research and its forceful application to practical operation. 2. A steady development in mechanization and automation leading to savings in manpower. 3. Improvization, modernization and adaptation of exisitng facilities. Thoughts on these themes can best be illustrated by comments on some of the industries visited. COAL The National Coal Board (N.C.B.) has been most progressive and all of us have heard of the Bevercotes Colliery with its completely automatic mining and coal handling equipment. This was not, unfortunately, on show but there is no doubt that this is one of the greatest advances in coal mining leading towards continuous production. Coal in Britain is fighting for its life against oil, North Sea gas, imported gases and nuclear power. Output is dropping, the less efficient collieries are closing down and efficiencies are steadily rising as the following tabulation indicates: In 1931: 1 million men produced 300 million tons of coal In 1947: 0.7 million men produced 230 million tons of coal In 1968: 0.4 million men produced 160 million tons of coal

By A. Vogelzang

The paper describes how the level of the water-table was reduced as a result of increased pumping of water from the mine. Because such a condition in an area where there is compactable material above solid dolomite results In surface movement, steps were taken to restore the water-table to its former level. These included the return of water underground via a sinkhole and boreholes, and the piping of water from another mine.

Jan 1, 1978

By A. M. Starfield

Discussion J. de V. Lambrechts (Fellow): The author's paper is a brilliant follow-up of an earlier paper by Starfield and Dickson.1 I have no quarrel with Dr Starfield's computerization of a complex problem, but I do not believe that he is getting quite the right answers from his programme. My impression is that his predictions about wet bulb temperature increases in very deep mines are over optimistic; in other words, that it will be hotter than Dr Starfield predicts. This is putting my views in a nutshell. This is not the occasion on which to indulge in lengthy argument about the original paper by Starfield and Dickson, but the present paper is, after all, based directly on that earlier paper and if the one fails, the other cannot succeed. I did level certain criticisms at the first paper and cannot say that the authors' replies were very convincing. I do not think it is a sin to admit that I belong to the old school which believes in thorough field experimentation and practical trials and no amount of mathematical manipulation or physical theorizing, no matter how excellent, can make up for inadequate practical confirmation. This, as I see it, is still the crux of the matter. The original paper by Starfield and Dickson still rests on somewhat scanty practical evidence and I would be much happier if Dr Starfield's computer programme, based on the Starfield-Dickson model, had been checked against a large mass of observations in the practical mining situation. This is what both Wiles2 and myself3 had tried to do previously. What we lacked in mathematics and/or computer aids, I think the present paper by Dr Starfield lacks in practical substantiation. This is no condemnation of the author's paper which, taken by itself, is excellent but I think the final stage is still lacking, namely the bringing together of theory and empiricism in a manner acceptable to all. This may be wishful thinking on my part but I hope, within the next year or so, to come up with a modified Starfield-Dickson model in such a way that the computer answers will agree in the majority of cases with the few hundred field observations which are already on record. It might be a case of applying the proverbial 'Cook's Law' to the Starfield-Dickson model! REFERENCES 1. STARFIELD, A. M., and DICKSON,A. J. 'A study of heat transfer and moisture pick-up in mine airways.' J. S. Air. Inst. Min. Metall., 68, (5), 1967. 2. WILES, G. G. 'Wet bulb temperature gradients in horizontal airways.' J. S. Air. Inst. Min. Metall., 59, (7), 1959, p. 339. 3. LAMBRECHTS, J. DE V. 'Prediction of wet bulb temperature gradients in mine airways.' J. S. Air. Inst. Min. Metall., 67, (11), 1967, p. 595. R. Hemp (Visitor): Dr Starfield's paper has very effectively rounded off one particular aspect of the general problem of heat flow in mines. The ease with which this computer programme can be used to calculate temperature increases in horizontal airways must lead to its wider use in ventilation planning and, in developing this rapid method, Dr Starfield has indeed rendered a valuable service to the mining industry. One could consider further instances of heat flow in airways in which the availability of a rapid computer method would be desirable, e.g. the flow of air down a shaft, where there is an increase in temperature due to adiabatic compression, as well as an increase in virgin rock temperature as the depth increases. However, this particular case would not present any new problems and would merely require an extension of the exisitng work. I should like in this contribution to talk about an aspect of environmental control in mines which, I think, will become more important in the future. It is well known that wet bulb temperatures are subject to fluctuations underground. In some instances, particularly in stopes, the fluctuations, both with time and position, can be considerable. The theoretical work which has been carried out on temperature increases has been aimed at the prediction of mean temperatures, and no account has been taken of fluctuations around this mean. It is questionable whether this approach will, on its own, be sufficient, particularly when temperature increases in stopes are considered. The fluctuations in air temperatures underground arise from two causes. The first of these would be the fluctuations in surface conditions, and here one could list random, diurnal and seasonal fluctuations. The second cause is the multitude of things which vary in a mine and here one could list variations in air flow quantity, sources of evaporation, heat transfer from pump and compressed air columns and, particularly in the stope, variations in air flow patterns. Fluctuations arising from surface temperature variations should be amenable to calculation, and here one envisages figures relating the decay of temperature variation with distance to factors such as air flow quantity. Fluctuations resulting from changes in the mine are perhaps more difficult to tackle theoretically and the best approach could well be to analyse underground observations. In this connection, there is a good case to be made for the increased use of statistical methods in the analysis of underground temperature measurements, and it might be of value to look at current air-conditioning practice. When carrying out cooling load calculations for a particular location it is customary to use design wet bulb

Jan 11, 1969

By N. B. Strydom

I have read with interest all the papers dealing with heat transfer and the setting of heat stress limits that have appeared during the past two decades. Scientifically speaking, most of them can be rated as being of a high standard, and some of them have been acclaimed internationally as masterpieces of logical and calculated reasoning. Weathering of ore minerals A short course on 'The Weathering of Ore Minerals and the Textural Evaluation of Base Metal Gossans' is to be given by Dr I.M. Reynolds in Grahamstown from 4th to 6th October, 1982.

Jan 1, 1982

The development of 3D multi-parametric models facilitate the provision of resource information well in advance of the mining face. Using the model, one can evaluate mining areas not only for grade and tonnage predictions but also for predictions of rock mass quality. Blast design and milling requirements can be derived from the rock mass quality predictions. This information can be used for overall mine planning and evaluation, costing, production optimization and slope design. This allows the full range of mining activities and costs to be interconnected, there by lowering costs and improving efficiencies through the application of the multi-parametric model. Feasibility studies for new projects require an expected budget expenditure estimate to within5% of actual costs. This level of accuracy is expected by mining companies and investors but cannot be achieved without a sound knowledge of the rock mass variability. By developing a 3Dmulti-parametric model as part of the feasibility study and using the same geological model exploration boreholes, a significantly better understanding of the rock mass conditions can be obtained. This rock mass information can be used for equipment selection, economic pit layouts, processing plant design, underground mining layouts and support requirements, to name but a few design parameters that depend on rock mass conditions. The initiative at Anglo Platinums, Potgietersrust Platinum Ltd.?s (PPRust) operation, has delivered significant results showing improvements across the mine to mill value chain. These include increased loading rates, reduced electricity and crushing consumables, as well as higher plant throughput. The ore reserve model has gained international acceptance as an invaluable tool for a mining operation. Certainly most financial organizations will not invest in a mining project that does not have an ore reserve model. There is the potential for multi-parametric models to be recognized as vital tools in the mining process, as is the case with ore reserve models.

Jan 1, 2006

By D. Clement

A comparison between hydraulic and pneumatic rockdrills by D. CLEMENT The regulation of compressed-air reticulation systems is very poor compared with that of electrical systems; this means that electrohydraulic rockdrill systems offer greater flexibility, additional power being readily available at the working face. Hydrometallurgy A new journal devoted to all aspects of the aqueous processing of metals is scheduled to appear this year. Entitled Hydrometallurgy, the journal will be published in quarterly issues, one volume per year. Mineral dressing Contributions are invited for the Symposium on Recent Progress in Mineral Dressing in South Africa, which is to be arranged jointly by the South African Institute of Mining and Metallurgy and the National Institute for Metallurgy. Mineraalbereiding Bydraes word verlang tot die Simposium oor Onlangse Vordering met Mineraalbereiding in Suid-Afrika wat gesamentlik deur die Suid- Afrikaanse Instituut vir Mynbou en Metallurgie en die Nasionale Instituut vir Metallurgie gereel gaan word. Rock mechanics The Sixteenth Symposium on Rock Mechanics is to be held at the University of Minnesota from 22nd to 24th September, 1975. The Symposium is the official Symposium for 1975 of the International Society for Rock Mechanics (I.S.R.M.), and the Council for I.S.R.M., consisting of members from 25 countries, will meet during the Symposium. Powder metallurgy The annual meeting on powder metallurgy organized by The Metals Society is this year to be held at the Stratford Hilton Hotel, Stratford-upon-Avon (the notification did not include the date of the meeting). Vacation School The South African Institute of Mining and Metallurgy has great pleasure in announcing its intention of holding a vacation school on the topic of electric-furnace melting. NIM reports Report no. 1681 The determination of sulphur and phosphorus in chromite. Report no. 1687 The viscosities and electrical conductivities of slags associated with the production of high-carbon ferromanganese alloys.

Jan 3, 1975

By B. Mulcahy, M. Valenta

"The purpose of executing a project in a stagewise fashion is to evaluate all potential options in a cost-effective manner and develop an understanding of the project drivers, thereby minimizing overall project risk to the client. Among the more valuable tools for this exercise are production and financial models that can be used to quantify the sensitivity of the project to the critical parameters.The mine and concentrator used in this case study are located on the Kalahari Copper Belt, which extends from Zambia through northern Botswana into Namibia. This area of Africa has seen very little industrial development and the project will create much-needed employment and development in the region.The success of this project thus far can be attributed to the close cooperation between the geological, mining, and metallurgical disciplines. Regular updates of projected capital and operating cost estimates coupled with project outputs guided the teams in optimizing their various discipline models, ultimately delivering a compelling argument for the execution of the project. Key to the success was the development of a geometallurgical model for the prediction of concentrate tonnage, grade, and recovery for the life of the mine from the mining plan.This paper summarizes the metallurgical findings and the outcome of the various project stages. The development of the model is discussed, as are the challenges faced in developing a suitable metallurgical process route. IntroductionThe Kalahari Copper BeltThe Kalahari Copperbelt, which extends from Zambia across northwest Botswana into Namibia, is considered to be a broad time equivalent of the Central African Copperbelt, with a similar style of mineralization. However, at shallower depths (<25 m), chrysocolla and malachite exist in significant proportions in certain geological areas. As illustrated in Figure 1, the project is located in the Ghanzi-Chobe Fold Belt which forms part of the Kalahari Copper Belt. The Ghanzi Group, which overlies the lowest stratigraphic unit (the Kwebe Formation), consists of three formations, namely the Ngwako Pan, the D’Kar, and the Mamuno Formation (Hall, 2012)."

Jan 1, 2016

By F. Hees, A. H. Bracken, L. I. Boshoff

"Biological cementation of the Mandena heavy mineral sand deposit in Madagascar was causing difficulty in dredge mining and hence in planning and control of production rates. An investigation was initiated to better evaluate the geotechnical properties of the orebody by defining the distribution and geotechnical properties of the cemented strata, in order to generate a site-specific geotechnical model for the deposit. The geotechnical characterization was developed by an integrated approach using several ground investigation techniques such as piezocone (CPTu) testing, geotechnical drilling, standard penetration testing (SPT), as well as laboratory testing. The final outcomes of the investigation included a 3D geotechnical model showing the distribution and extent of the cemented areas, as well as the typical geotechnical parameter ranges associated with each of the defined geotechnical units. The interpretations developed were incorporated into the mine and production planning to ultimately optimize operational planning and control.IntroductionQIT Madagascar Minerals (QMM) is a heavy mineral sand mining operation at Mandena, near Fort Dauphin in Madagascar. During the final planning and commissioning stages of the project, the need to fully characterize the unusual geotechnical conditions was identified and a geotechnical investigation became necessary.Nature of the problemDuring the commissioning phase it was found that mining production was being hampered by biologically cemented/indurated layers encountered within the sands. Closer inspection of the indurated horizons in the dredging face revealed that these layers contain a high loading of bacteria and fungi. It appears that the bacteria produce an extracellular (outside the cell) polysaccharide (i.e. sugar and carbon salts), which form a gelling biofilm to trap nutrients. There are a number of different bacteria. The fungi, on the other hand, produce a network of fibrous strands that bind the sand grains together. Thus both bacteria and fungi probably contribute to the ‘apparent cohesive’ strength or binding of the indurated sand (Lynn, 2008)."

Jan 1, 2017