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The Department of Mineral Resources of Thailand is organising, on behalf of the Government of Thailand and the International Tin Council, the Second Technical Conference on Tin. The Conference will be held at Sala Santitham, Bangkok from 18th to 22nd November, 1969. Papers will be grouped under three main headings: (i) Geology and prospecting; (ii) Mining and ore dressing; (iii) Miscellaneous, e.g. stimulating production, metallurgy, estimation of reserves etc. Pre-prints of papers will be circulated. A field trip to Southern Thailand has been arranged for 25th November to 2nd December, 1969. Details of the Conference and the field trip can be obtained from Mr. W. Fox, International Tin Council, Haymarket House, 28 Haymarket, London, S.W.l, England.

By M. J. Daly

Historically, engineers and scientists, particularly those involved in the coal-mining industry, have been slow to adopt statistical methods. However, the need to obtain the maximum information .from expensive exploration and development programmes, and the current focus on total quality management, have led to a change in perceptions if classical statistical and geostatistical methods and their application as planning tools. Some if the underlying issues associated with the generally poor communications between statisticians and engineers/physical scientists, which contribute to some if the misconceptions relating to statistical methods, are discussed The potentially profitable application if a number if statistical techniques in the fields if geological evaluation and mine planning! development is also reviewed, with specific reference to the coal industry.

Jan 1, 1995

Recent advances in the design and performance of flotation equipment A General Meeting and Colloquium on the above topic was held on 12th March, 1975, at Kelvin House, Johannesburg. The Colloquium was attended by 250 delegates and was opened by the Immediate Past President, Mr P. W. J. van Rensburg, at 09h30. Obituary Mr Van Rensburg announced with regret the deaths of James Alfred Boyd, Life Fellow, and Jack Joseph Frankel, Fellow. Training of technicians The Institute has received a letter from The Federation of Societies of Professional Engineers pointing out that there is considerable opportunity for the training of Coloured and Bantu technicians and artisans, and that the existing facilities will be extended as the demand for them increases.

Jan 6, 1975

By H. White

The applicability of ground penetrating radar (GPR) in numerous qualitative applications has been demonstrated over the past five years in the South African mining industry. These applications include the delineation of faults and dykes, fracture mapping, delineation of shear zones, mapping of depth of weathering, and the delineation of contact between different rock types. The qualitative nature of the data collected using existing commercial GPR systems, often relying on expert interpretation, has however mitigated against the full scale routine application of GPR in the mining industry. The recent development of the RockRadar system by ISS International has, to a large extent, overcome these problems. The result is that quantitative rock-mass studies can now be performed with the RockRadar system.

Jan 1, 1996

By R. Guest

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

Jan 1, 1982

By W. F. Lorch

Growing use of deionised water in surface coating techniques by w. F. LORCH Production engineers in the metal plating, paint, plastics-coating and printed circuit industries are increasingly aware of the cost of sub-standard or blemished items which have been poorly processed. An area where quality control can quickly produce higher efficiencies is in the choice of suitably purified water for making up solutions, for rinse baths and 'drag-out' baths, for cleansing lines and electrophoresis tasks, for maintaining electrolyte density and hence consistency, and for facilitating the recovery of valuable minerals. The author of this article examines the general problems of using nonpurified water, and shows how purified water has become accepted by the principal surface coating industries to improve processes and effect economies.

By I. Wayland

Value added blasting is a process methodology that links tasks and processes, with the aim to improve/enhance the technical application of explosives technology and initiating systems, resulting in improved output. The phases and steps of a typical value added blasting intervention are discussed in this paper. Each step having distinct purposes, principles and methodology. The underlying philosophies and process steps of the programme are described for each step. This paper gives an account of projects that have been completed in two Anglo American Gold Mines. This will include a description of the projects that were conducted at Vaal Reefs 8 Shaft and Western Deep Levels South Mine covering: ? The need for blasting improvements ? The approach that was followed ? The result of the programme.

Jan 1, 1999

By S. Visage

By 1984 Iscor's first direct-reduction plant will be operating at the Vanderbijlpark Works, and for the fin;t time the Corporation will have an alternative method to the blast furnace for producing iron from ore. The performance of Iscor's four-kiln plant, which will be the largest coal-based plant in the world producing sponge iron, will undoubtedly be watched with great interest by steelmakers throughout the world. Beneficiation of tin The Southeast Asia Tin Research and Development (SEATRAD) Centre is a regional oganization, formed by the Governments of Indonesia, Malaysia, and Thailand with assistance from the United Nations, to conduct, coordinate, and promote research and training in the various fields of tin production, including geology, prospecting, mining, mineral processing, and smelting.

Jan 1, 1982

By A. G. W. Knock

Logistic curves are used in the prediction of the primary production of tin metal from estimated worldwide resources. Such curves are asymptotic to the total cumulative reserves, which are a function of prevailing metal prices and total resources. The figures for tin resources are based on the findings of Robertson and of Brobst and Pratt, the latter authors including estimates of undiscovered deposits. It is suggested that tin production will slump from the present level to 100000 long tons per annum by the end of the century, but will reach a new peak of 200 000 long tons some thirty years later. It appears that production will never exceed 300000 long tons per annum unless substantial new resources, excluding those predicted, are discovered.

Jan 1, 1979

By M. Mrost

Slimes disposal at South African gold mines by M. MROST*. M.Sc. (Rand) (Fellow) The soil mechanics, civil engineering, and environmental considerations applicable to the construction of slimes dams on the Witwatersrand gold mines are discussed. It is concluded that, though the procedures used in the construction of dam embankments do not accord with the best possible practice, they are entirely adequate in current local circumstances, provided that proper precautions are taken to ensure that the wall foundations are sufficiently permeable and strong, and that the dams are protected against erosion. If current trends towards larger mining and metallurgical complexes continue, it may become necessary to build larger, higher dams, and to adopt slimes embankmentbuilding practices that are inherently more reliable.

Jan 2, 1974

By P. Kohler, T. D. Sampson, T. H. Tunley

The Metsep Process for the separation and recovery of zinc, iron, and hydrochloric acid from spent pickle liquors by T. H. TUNLEY, B.Sc. (Ch em. Eng.) (Visitor), P. KOHLER (Visitor), and T. D. SAMPSON, Pr. Eng., B.Sc. (Chem. Eng.), B.Econ. (Visitor) A spray roaster has been installed in the Johannesburg area for the treatment of spent liquors from a variety of small pickling operations. A new process was developed for the processing of the liquor that is contaminated with zinc chloride, and a commercial plant was built incorporating this process. An ionexchange plant separates the zinc from the iron chloride, and a liquid-liquid-extraction plant converts the zinc chloride to zinc sulphate and recovers the hydrochloric acid.

Jan 5, 1976

By R. G. B. Pickering, H. H. Haase

CONTRIBUTION BY D. O'CONNOR Mechanical extraction of rock has been a goal sought after for some decades in the South African gold-mining industry. There are factors distinct from the mode of mechanical extraction that may have considerable influence on its prospects for extensive adoption; the rockburst factor is one of these. REPLY BY H.H. HAASE AND R.G.B PICKERING We agree with Professor O'Connor that, in conventional gold-mining operations, a disproportionate number of seismic events occur in the period immediately following a blast; rockburst activity follows the same pattern, and it has been calculated that, if the rockburst peak were spread evenly across the day, the rockburst exposure of stope workers would nearly double.

Jan 1, 1992

By M. T. Scholtz, I. J. Corrans

Akinetic study of the leaching of pentlandite in acidic ferric sulphate solutions by I. J. CORRANS, (Pr. Eng.). B.Sc. (Chem. Eng.) (Wits.). M.Se. (N.S.W.). Ph.D. (Natal) (Member) and M. T. Scholtz. B.Sc. (Chem. Eng.) (C. T.). Ph.D. (Toronto) (Visitor) A study was made of the kinetics in the leaching of nickel from pentlandite in dilute-acidic ferric sulphate solutions as a basis for subsequent studies on bacterial leaching. The chemical leaching rate was found to be highly dependent on the temperature and the concentration of ferric ions. The proposed mechanism for the leaching process is one involving rate control by chemical processes and mass transport. Good agreement was found between the experimental data and the proposed mechanism.

Jan 5, 1976

By J. D. Austin, D. G. Kringe

Rates of return realized on investments in the gold mines of the newer goldfields outside the Witwatersrand were calculated and analysed over various time intervals and on various bases. It is shown that these rates of return are strongly correlated with changes in the gold price and cannot be equated with the returns that are expected when investments are made, and that the changes in gold price also affect the rates of return on the Johannesburg Stock Exchange as a whole. These correlations are used, together with a limited application of the Capital Asset Pricing Model, to suggest the expected levels of threshold returns in real terms for new mining projects, for projects on existing mines, and for share valuations.

Jan 1, 1980

By R. J. Davidson, N. Schoeman

SYNOPSIS The paper describes each of the stages in a carbon-in-pulp (CIP) or carbon-in-leach (CIL) plant, and details the steps that can be taken to achieve effective carbon management by referring to practices at the Daggafontein CIP plant. This approach was adopted because of the difficulty in summarizing current carbon management in the many varying operations in South Africa, Daggafontein being chosen as a high-tonnage dedicated well-run plant of recent design. Because of the major role played by the consumption of carbon in the operating costs of CIP and CIL plants, an attempt is made to develop a series of indexes based on quality parameters and price that can be used as a guide In the selection of carbon.

Jan 1, 1991

Two column flotation cells have been installed as single-stage rougher cleaners at Batu Hijau. The objective was to provide additional residence time in the cleaner circuit to maintain maximum recovery during high mill throughput and high feed grade periods. Installation of the columns has allowed the relatively coarse, well-liberated rougher concentrate and the relatively fine, low-grade scavenger concentrate to be treated separately, improving metallurgical performance in the cleaner circuit. Plant results show that the columns produce a high-grade concentrate at an average stage copper recovery of approximately 80 per cent. There is also indication of increases in both overall plant copper recovery and final concentrate copper grade. In addition, the operability and stability of the cleaner circuit has greatly improved.

Jan 1, 2007

By J. Keyser

The realization of an Integrated Technical Resource Asset Management System (ITRAMS) has so far evaded all software developers in the mining industry. The major factors that have prevented the development of such a system are limitations on software, hardware and network systems. Several factors have come together at Venetia Mine, which has made the undertaking of such a project both possible and desirable. This has led to the formation of a strategic partnership between Venetia Mine and Gemcom Software International Inc. This partnership is dedicated to develop and provide an Integrated Technical Resource Asset Management System based on Microsoft Back Office architecture, Gemcom for Windows™ and the MinRas system. This paper will elaborate on the phased approach of the integration of systems into the core repository, mechanisms of integration, the functionality of the system, final results, techno-economic benefits and general project management issues.

Sep 1, 2001

By G. J. Wright, M. J. Neale

As machines become more complex and vital to our way of life, any disturbance or failure of their proper functioning tends to have serious consequences. To prevent such failures, increasing attention is being paid to techniques for the monitoring of machinery condition or 'health'. Of the many methods available, examination of the lubricant and any particles it contains forms a basis for interpretation of the conditions of operation, and the rate and severity of degradation of the moving parts, in a machine. Many techniques of wear-debris analysis, such as spectrographic oil analysis and ferography, are available indicate the composition, shape, size, and concentration of contaminants in a lubricant. This paper reviews the important aspects of wear-debris analysis as an integral component of machinery condition monitoring, and gives an insight into the selection of appropriate techniques and the information that can be obtained from each.

Jan 1, 1987

The Annual General Meeting of The South African Institute of Mining and Metallurgy was held in Kelvin House on Wednesday, 18th August, 1982. Mr G. Y. Nisbet (President) was in the chair and declared the meeting open at 16h05. Obituaries President: It is my sad duty to announce the deaths of the following members of the Institute: Honorary Life Fellow J. A. Taylor ; Life Fellows J. Watt and J. J. Cairns ; Fellows J. H. Mortimer, R. R. M. Cousens, H. Clark, S. W. Hill, Dr A. Whillier, and Dr C. M. van H. van Staden; Members F. W. McElroy, V. J. Irsigler, B. J. R. Botha, and E. J. Jackson; and Associate B. V. Robertson. As a mark of respect to the memory of the deceased and in sympathy with the bereaved, please rise and ob¬serve a few minutes of silence.

Jan 1, 1982

By J. H. Bulloch

The paper gives an assessment of the available data on the linear elastic fracture mechanics involved in stress corrosion cracking and in the behaviour of reactor pressure-vessel materials exposed to a simulated pressurized water-reactor environment. As a result of the different experimental techniques used in the various studies mentioned, only a few detailed conclusions can be drawn. The data from constant-displacement wedge-opening loading (WOL) tests, with the exception of one study, exhibited very limited or no crack extension during exposure periods of up to 14000 hours. The data from constant-load tests indicated evidence of crack extension, but the nature and extent of the crack extension are still unclear. When crack extension did occur, it was exclusively transgranular in nature. Certain differences in the available test data are tentatively explained in terms of the experimental procedures used, and the need for a consistent code of experimental techniques is highlighted.

Jan 1, 1987