Search Documents

By R. W. O. Kersten

The main objective of The South African Institute of Mining and Metalurgy is to identify the needs of the mineral and metals sector of the South African economy, and to initiate the means by which the requirements for technology and scientific knowledge can be satisfied. To achieve this, the Institute organizes schools to promote technology transfer and to satisfy the needs of its members for continuing education by the exchange of technical information, the communication of ideas, and the identification of technological problem areas.

Jan 1, 1986

By L. A. Vermeulen, D. D. Howat

A study was made of the performance of a rod mil operating without liter bars and with different arrangements of liter bars in the lining. . The results show that striking improvements in performance, increased throughput, and reduced consumption of liner metal and electrical energy can be obtained by a change in the geometry of the liter-bar arrangements within a mil. Rod mils of equal size fitted with the same arrangement of liter bars but operating at different speeds presented apparent anomalies in the relative consumption efficiency of electrical energy for the production of material smaller than 75 µ m. Marked savings in the consumption of liner metal were achieved by the use of an arrangement of alternating lines of higher and lower liter bars. A study of the relative performances of two large tube mils showed that the use of liter bars in one of the mils resulted in a marked reduction in the consumption of liner metal and electrical energy per ton of material smaller than 75 µ m in the product.

Jan 1, 1986

By G. J. Kringe

The results of a series of measurements of accelerations and guide-roller loads made on mineshaft conveyances are given, together with the predictions of these accelerations and loads based on a computer programme. The analysis of the measurements is described, and the results of the measurements and computer predictions when compared show reasonable agreement. Some parameters that increase the guide-roller loads are identified, and their effects are studied, together with some comments on the total loads. Finally, a possible format for a design specification is discussed, and some tentative design values are given.

Jan 1, 1986

A Special General Meeting of The South African Institute of Mining and Metallurgy was held at Kelvin House, Johannesburg, on Wednesday, 20th August, 1986. Mr H.E. James (President) was in the chair and declared the meeting open at 15h45. Background The Chairman explained that the meeting had been called to consider a number of amendments to the SAIMM constitution. The proposed changes had been set out in detail in a document that had been mailed to all members on 4th July, 1986. He then briefly reviewed the background to the proposals, which is outlined in the Preface to the Annual Report (page 357 of this issue). The Chairman added that the Executive Committee of SACPE at its meeting on the 8th August, 1986, had resolved that the proposed amendments to the SAIMM constitution did comply with the requirements of Regulation RI525 dated 17th July, 1981, regarding the recognition by SACPE of a society as a Professional Engineering Institute.

Jan 1, 1986

PREFACE During the past year, the Council of the SAIMM undertook a major strategic-planning exercise to review all its current activities, and to redefine its scope and objectives in the light of changing circumstances. The following are the four main concerns that prompted Council to take stock of the situation. (1) Over the past five years, the SAIMM has become heavily involved in a variety of new activities. (There are many examples, of which the expansion in book publications and the establishment of physical metallurgy as a third major discipline with its own colloquia and schools are perhaps the most important.) While these new activities have considerably broadened the SAIMM's scope, they have resulted in a significant increase in the day-to-day workload of the President, Office Bearers, and Council members, and of the secretarial staff based at Kelvin House.

Jan 1, 1986

By W. F. A. T. Meihack

The scope of this paper is confined to gas-fluidized beds in pyrometalurgical applications. After considering the general characteristics of these fluidized beds, the author deals with their potential applications, using the following processes, which are currently under investigation, as examples: pretreatment of chromite, prereduction of manganese-ore and iron-ore fines, roasting and prereduction of ilmenite, and roasting and pyrolysis of gold-bearing pyrite. He concludes that fluidized beds are potentially of great benefit to the metallurgical industry, although much developmental work remains to be done.

Jan 1, 1986

By H. Wagner

In 1980 The South African Institute of Mining and Metallurgy instituted the Brigadier Stokes Memorial Award to commemorate the outstanding contribution to the South African mining industry made by Brigadier R.S.G. Stokes, who was an Honorary Life Fellow and a Past President of the Institute.

Jan 1, 1986

By C. T. Connor, O&apos

The fifth University of Cape Town (UC1)/University of Stelenbosch (US) Minerals Processing Symposium was held at the Faculty of Engineering, University of Stelenbosch on Friday, 8th August, 1986. This series was initiated in 1982, the symposia being held alternately in Cape Town and Stelenbosch. The South African Institute of Mining and Metallurgy has kindly agreed to sponsor this event for the next three years. Cokemaking On the initiative of the European Cokemaking Commitee, the First International Cokemaking Congress will be held in Essen (F.R. Germany) from 13th to 19th September, 1987. It is being organized by the Steinkohlenbergbauverein, together with the Verein Deutscher Eisenhitenleute.

Jan 1, 1986

On Friday, 18th April, 1986, Stefen Kenneth de Kok passed away peacefully at his home in Johannesburg after a short illness. New President of FSPE Mr R.G. (Bob) St Leger took office as President of The Federation of Societies of Professional Engineers on 1st July, 1986.

Jan 1, 1986

By A. M. F. Carter

A survey was conducted so that the degree of corrosive, erosive, and abrasive attack on material-handling systems in the mining and mineral-processing industry could be assessed, and so that the areas of research and development that would be relevant to the needs of the industry could be determined. Of the 59 different mines that were invited to participate in the survey, 41 returned completed questionnaires, giving a return rate of 70 per cent. The total number of completed questionnaires amounted to 45. An analysis of the results shows that attack by erosion or abrasion is considered to occur more often than attack by corrosion. However, al three types of attack must be regarded as significant problems within the mining industry, since 52 per cent of the participating mines reported pump failures due to the inability of the materials of construction to withstand the operating conditions, and almost 90 per cent reported piping failures due to corrosion (22 per cent) or to erosion and abrasion (78 per cent).

Jan 1, 1986

By J. W. S. Koel, T. R. Twidle, P. C. Engelbrecht

The process flows of the three flotation circuits at the concentrator of the Black Mountain Mineral Development Company (Pty) Ltd are described. Because of the complexity of the circuits and the associated reagent regime, the plant is equipped with a comprehensive range of control equipment. The different process-control strategies are discussed, and the modifications that have been necessary to the stabilizing control loops in the copper, lead, and zinc flotation circuits are shown in detail. It is concluded that the control strategies have continued to bring about benefits and improvements to the process.

Jan 1, 1986

By H. Wagner

The discovery of the gold-rich Main Reef Group of reefs on the farm Langlaagte in 1886 marked the opening of the richest and most extensive goldfield in history. Mining of the narrow reefs progressed from the outcrops to more than 3,5 km, and has made South Africa the foremost mining country in the world. Changes in the political and socio-economic climate create a new challenge to the gold-mining industry. The most significant of these is the emergence of Black trade unions, with their demands for higher wages, improved safety, job advancement, and abolition of discriminatory legislation. Industrial conflicts on gold mines have risen significantly in the past ten years, and are likely to continue in the future, although the causes of these conflicts may change. Events largely outside the control of the gold-mining industry, such as the improved dollar price for gold and the depreciation of the value of the rand relative to major currencies, have enabled the industry to meet the demands for higher wages and to narrow the wage gap. However, labour productivities have improved insignificantly and are a cause of major concern for the future development of the industry. Continued pressure in the industrial-relations area, the inflation of working costs, and the extension of mining operations to greater depths and more difficult areas create major challenges to mine managements and mining engineers. Significant improvements in mining technology, environmental control, and safety will have to be made to ensure the long-term survival of the industry. The unavoidable introduction in deep gold mines of mechanization on a larger scale to meet the requirements of higher labour productivities and a better and safer underground environment will have a major impact on the cost and management structure of these mines. Engineering will assume a more important role on deep gold mil1es, and management styles and structures will have to be adapted to accommodate these changes. The supply of suitably qualified engineers, technicians, and artisans will be a crucial factor controlling the rate of technological change. The industry is well-geared through its Group system to meet these challenges, and to benefit from the experience gained in the operation of highly mechanized mines. However, changes take time to implement and there is very little time left.

Jan 1, 1986

By R. M. Falcon

The paper opens with a summary of the major factors responsible for spontaneous combustion in coal discards. These include heat arising from the oxidation of coal and pyrite, and from the weting of dry or oxidized coal and pyrite; and certain petrographic conditions leading to self-ignition of the coal such as low rank, the presence of a high proportion of reactive constituents, and the occurence of highly porous and botanicaly structured inertinite macerals, The analyses of 6 samples from 2 discard dumps in the Witbank coalfield are included, which show that, according to a three-grade classification of liability to spontaneous combustion, one dump is 'reasonably liable' and the other is 'most liable', It is pointed out that factors other than liability to self-ignition determine the possible utilization of such discards, and that the prevention of oxidation is of great importance if they are to be utilized and spontaneous combustion to be prevented,

Jan 1, 1986

In mid-1984, SAIMM reached an agreement with the South African Region of what is now the Institute of Metals to combine the physical-metallurgical activities of the two organizations. This was the outcome of several years of informal collaboration, and followed the recognition in 1982 by the SAIMM Council that applied physical metallurgy had grown in importance to South African industry and should have a place alongside the two areas already well-established for SAIMM commitment and support-mining and extractive metallurgy.

Jan 1, 1986

By W. C. Mather

The Witbank/Middelburg Branch of The South African Institute of Mining and Metallurgy hosted a colloquium entitled 'Recent Mining and Metallurgical Developments in the Eastern Transvaal', at the Witbank Civic Centre on Wednesday, 25th September, 1985. An attendance of close on 300 delegates bore testimony to the popularity of the theme. Two well-attended cocktail parties were held at different venues on the evening prior to the Colloquium. These were hosted at the South African Coal Estates Recreation Club and Middelburg Country Club.

Jan 1, 1986

By J. D. Wells

An account is given of the planning required for the rehabilitation of land that is to be disturbed by opencast mining, and of the preparation of rehabilitation of land that is to the Inspector of Mines. The plans Include the provisions that are to be made to allow for climatic conditions, land use, vegetation and wildlife, surface-water resources, geology and ground water, soils, land capability, rehabilitation method, location of discard dumps and slurry ponds, pollution control, and costs. . . Monitoring of the operation is the only way that the rehabilitation plan can be improved, and both monitoring and planning are essential when provision is being made for the closure of a mine.

Jan 1, 1986

1. Book reviews Dislocations and properties of real materials, edited by M.H. Loretto. London, The Institute of Metals, 1985. 392 pp. Reviewer: F.R.N. Nabarro Au &Ag heap and dump leaching practice, edited by J.B. Hiskey. AIME, 1984. 162 pp. $20 (member), $15 (student member), $30 (non-member) plus $3.50 for postage and handling. (Order from SME Books, Caller no. D, Littleton, CO 80127, U.S.A.). Reviewer: R.A. Snodgrass The cost and availability of Colombian coal, by Eric D. Jamieson, with the assistance of Kathleen Jamieson. London, lEA Coal Research (14/15 Lower Grosvenor Place, London SWl W OEX). £50 (in member countries), £100 (in non-member countries). Reviewer: W.C. Mather Extraction Metallurgy '85. London, The Institution of Mining and Metallurgy, 1985. £42. Reviewer: R.A. Snodgrass 2. Recent publications Mining annual review 1985. London, Mining Journal, Jun. 1985. 600 pp. £26.50 (surface), £39.50 (air). High heat production (HHP) granites, hydrothermal circulation and ore genesis. London, The Institution of Mining and Metallurgy, 1985. 593 pp. £27 (members), £30 (non-members). Potential mineral resources of Egypt. 144 pp. US$10. Available from Bendix Field Engineering Corporation-MPGAP, Box 1237, Grand Junction, CO 81502, U.S.A. 3. Mintek reports Report M212 South African costs of equipment for the metallurgical industry (1984). Report M213 The response of as-rolled 3CR12 steel to heat treatment. Report M214 A computer programme for use in the development of multi-element X-ray-fluorescence methods of analysis. Report M221 Commodity profiles for selected metals. Report MIO7D Upgrading of alaskite rock to feldspathic sand. (First issued Jun. 1983; reissued Nov. 1985). IMM awards Given below are details of the trust funds to which applications are invited for grants, etc., payable in 1986. Application forms, which must be returned to the Secretary before 17th March, 1986, are available on request. Applicants should note that, in general, preference will be given to members of the Institution.

Jan 1, 1986

1. Reviews Steel and its heat treatment, by K-E Thelning. 2nd Edition. London, Buterworths, 1984.678 pp. R201,60 (incl. OS1). Reviewer: J.P. Hofman The Southern Queensland Conference 1985. Parkvile (Australia), The Australasian Institute of Mining and Metallurgy, 1986. A$ 15.00. Reviewer: R.B. McGilivray Rock mechanics, by A.R. Jumikis. 2nd edition. Clausthal-Zelerfeld (West Germany), Trans Tech Publications, 1983. US$ 58. Reviewer: R.W.O. Kersten The XVIth International Coloquium on Refractories. Freiburg, West Germany, 1985. DM 80. Reviewer: H.J. S. Kriek Diamond driling handbook, byW.F. Heinz. Johannesburg, South African Driling Association, 1985. 517 pp. R30. Reviewer: S.A.G. Martins Processing and utilization of high sulfur coals, edited by Y.A. Atia. Amsterdam, Elsevier, 1985.788 pp. Oft. 385. Reviewer: L.M. Falcon Weighingand proportioning of bulk solids, by Hendrik Colijn. 2nd edition. Rockport (U.S.A.), Trans Tech Publications, 1983. 398 pp. $60.00. Reviewer: G. Cunningham Investment appraisal and economic evaluation of mining enterprise, by S. von Wahl. Clausthal-Zelerfield (West Germany), Trans Tech Publications, 1986. US$ 40. Flotation of sulphide minerals, edited by K.S. Eric Forssberg. NewYork, Elsevier Science Publishers, 1985. 480 pp. US$1O1.75. Reviewer: T.R. Twidle 5th Meeting of the European Clay Groups (5th Euroc/ay Meeting), Prague, edited by J. Konta. Praha (Prague), Univerzita Karlova, 1985. Reviewer: D. Bibmann 2. Recent publications CSIRO. Research review1982-84: CS/Ra Division of Mineral Engineering. Melbourne, Commonwealth Scientific and Industrial Research Organization, 1985. 77 pp. The world copper market: structure and econometric model, by Gerhard Wagenhals. Berlin, Springer- Verlag, 1984. 202 pp. DM 37,00.Materials data of high-strength aluminium aloysfor durability evaluation of structures, edited by L. Schwarmann. Disseldorf (West Germany), Aluminium- Verlag GmbH, 1985. BRITISH GEOLOGICAL SURVEY. UnitedKingdom mineral statistics 1985, compiled by H.c. Squirel, A. Jones, N.E. Sharp, M. Lowe, and D. Slater. Keyworth (U.K.), the Survey, 1986. 175 pp.3. Mintek reports Report Ml66D The effect of calcining on the recovery of gold in a sand residue. (1st issued Sep. 1984.) Report M168D The treatment of Uitkomst concentrate. (1st issued Oct. 1984; reissued Mar. 1986.) Report M175D Supergene alteration at the Pering zinc-lead deposit: The nature and extent of the oxidation zone. (1st issued Oct. 1984.) Report M176D Bench-scale tests on the extraction of cobalt and nickel from COMAT leach liquors. (1st issued Nov. 1984; reissued Mar. 1986.)Report M241 PLA TO at Mintek. Report M243 The performance and wear characteristics of grinding media as affected by metallurgical and dimensional factors. Project development The Second Project Development Symposium on Planning, Construction and Commissioning will be held in Sydney, Australia, from 7th to 10th October, 1986. Hosted by the Sydney Branch of The Australasian Institute

Jan 1, 1986

1. Book review The geology of some northern Nigerian anorogenic ring complexes, by J.N. Bennet, D.C. Turner, E.C. Ike, and P. Bowden. The British Geological Survey: Overseas Geology and Mineral Resources, no. 61. London, HMSO, 1984. 66 pp. Reviewer: R.H. Ingram 2. Mintek reports Report M226 The separation of tungsten and molybdenum by the formation of sulphide complexes and extraction into a weak-base resin. Report M228 The solvent extraction of zinc, iron, and indium from chloride solutions by neutral organophosphorus compounds. Report M230 Shear flocculation of fines for improved flotation. Report M239 A mineralogical study of residue from the column leaching of a low-grade nickel-copper sulphide ore.3. Recent publication Driger Review, special edition, act. 1985. 48 pp. (Copies obtainable from Roly Nyman, HAMPO PMIE Division, P.O. Box 170, Joham1esburg 2000.) Black Mountain's achievement The 13 689 t consignment of metal concentrate that was loaded aboard the bulk carrier 'George' and shipped out of Saldanha Bay early in December brought the number of tons exported from Black Mountain via the Sishen-Saldanha railway and harbour system to one million.

Jan 1, 1986

Book reviews Natural gas substitutes from coal and oil, by S.A. Qadar. Amsterdam, Elsevier Science Publishers, 1985. U.S.$83.25. Reviewer: U. Grimsehl High heat production (HHP) granites, hydrothermal circulation and ore genesis. London, The Institution of Mining and Metalurgy, 1985. 593 pp. £30. Reviewer: S.A. de Waal 2. Recent publications Uranium recovery from phosphates and phosphoric acid, by S. Huwyler. 3rd edition. Wirenlingen (Switzerland), Swiss Federal Institute of Reactor Research, EIR-Bericht (C) no. 1. Apr. 1985. 56 pp. Geological aspects of mining productivity. Canada's base metal resources, by B.W. MacKenzie. Kingston (Canada), Centre for Resource Studies, Queen's University, Technical Paper no. 6, Aug. 1985. 115 pp. $10.Taxation policies in the Canadian minerals industry, edited by M. Wojciechowski. Kingston (Canada), Centre for Resource Studies, Queen's University, 1985. Mineral policy update 1984: Policy and program changes afecting the Canadian mineral industry, by M.l. Wojciechowski and M.L. McAlister. Kingston (Canada), Centre for Resource Studies, Queen's University, 1985. $12. 3. Mintek reports Report MU7 The selective solvent extraction of pal/adium by the useof di-normal hexyl sulphide. Report M218 Modification of the design of screen boxes for carbonin-pulp and resin-in-pulp plants. Report M225 The commissioning, operation, and maintenance of an on-line corosion-monitoring station for the mining industry. Report M231The determination of selected lanthanoid elements by atomic-absorption spectroscopy using electrothermal atomization. Report M233 A computer programme for the prediction of hydrocyclone performance, parameters, and product size distributions. Report M234 The solvent extraction of base metals by mixtures of carboxylic acids and non-chelating oximes. 6 The efect of particle size and coloid stability on the wet high-intensity magnetic separation of uranium from cyanidation residues. Report M238 The beneficiation of fine coal. Report M240 The spectrophotometric determination of tin in silicates and tungsten-bearing materials. Report M242 Wear and performance of materials in pipelines for the hydraulic conveyance of fused ash. IPMI award for distinguished achievementThe International Precious Metals Institute has announced that Professor Henry C. Taube, Nobel Laureate, wil be the recipient of their 1986 Distinguished Achievement Award. Dr Taube is Professor of Chemistry at Stanford University, Palo Alto, California.

Jan 1, 1986