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By R. D. Hancock

The complex responsible for the poisoning of anion-exchange resins is identified as the anionic cobaltic penta¬cyanide mono aquo species. It is shown that, at high concentration, this species polymerizes in solutions of pH less than 9. A mechanism for poisoning is presented that involves adsorption of anionic cobalt cyanide by a normal ion-exchange process, followed by polymerization within the resin matrix to form complexes that are too large to diffuse readily through the resin pores. The effects of resin structure and functionality on the extent of cobalt poisoning are examined, and the effect of cobalt poisoning on the kinetics and equilibrium loading of uranium is discussed.

Jan 1, 1979

Financial Times Mining International Year Book 1979. London, The Financial Times Limited, 1979. 712 pp. Price: airmail, U .S. $60,00; surface mail, U .S. $42,00. International Wrought Copper Council. Glossary of terms applicable to wrought products in copper and copper alloys. London, the Council (6 Bathurst Street, Sussex Square, London W2 2SD), 1978. 170 pp. 80 Swiss francs (approximately £25). Council of Mining and Metallurgical Institutions At a meeting of the Council of Commonwealth Mining and Metallurgical Institutions held on 15th January, 1979, it was unanimously agreed that the name of the Council should be changed.. Assaying and analytical techniques This year sees the Diamond Jubilee of the South African Institute of Assayers and Analysts, which held its first meeting on the 3rd of May, 1919.

Jan 1, 1979

INTRODUCTION The SAIMM publishes technical information on various aspects of the minerals industry through several different media. (a) Monograph Series Books in the Monograph Series are high quality, detailed discussions on specialized topics. (b) Symposium Series This series consists of the proceedings of international conferences which are held in South Africa. (c) Special Publications Series This series covers titles which do not form part of the Monograph and Symposium Series. (d) The SAIMM Journal Papers published in the Journal cover al relevant areas of technical interest by striving for a balanced content and maintaining a consistently high technical standard. (e) School and Colloquia Notes The papers from al local schools and colloquia are published and handed out at registration. Should authors wish to have their papers considered for publication in the Journal, they should adhere to the guidelines outlined below.

Jan 1, 1991

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 S. M. Rupprecht

The transportation of men, material and rock in mechanization programmes is often neglected, or at least plays only a secondary function, as the primary focus is on proving the technology. This is despite recognition of the fact that mechanization is essential if gold mines are to remain competitive. However, the use of totally mechanized systems will require further research in the short to medium term before they become generally available. Thus, there is a real need to improve mechanized men, material and rock transportation systems as they are currently used. This applies to both reef horizons as well as to horizontal transport systems. Keywords: Transportation, rock handling, material handling, men transportation, face cleaning, gully cleaning, continuous scraper, monorail, mechanized raise climber, mechanization.

Sep 1, 2001

By D. J. Adams, R. G. Gürtunca

In situ measurements and numerical modeling based on elastic theory showed that backfill stresses are considerably higher than originally thought. This has led to a change in understanding of rockmass behaviour. After describing previous work on the behaviour of the rockmass, this paper discusses possible reasons for the high stresses measured in backfil, and identifies the rockmass mechanisms possibly generating these stresses. It is concluded that the joints and the geological stratigraphy can lead to increased elastic convergence, and that the inelastic behaviour of the rockmass is also partly responsible for the increased closure measured in backfill. The use of an in situ modulus is suggested as an interim solution until a new computer model that allows for joints, different layers, and inelastic closures becomes available.

Jan 1, 1991

Results from a study undertaken at a Transvaal colliery on the feasibility of undermining an urban development by conventional bord-and-pillar mining operations in the No. 4 Seam of the Highveld Coalfield are discussed. Surface ground vibrations above production sections were measured, analysed, and then compared with well-accepted guidelines so that the expected effects of vibration on inhabitants and surface structures could be determined. The measurement and scaling of ground vibration from blasting are outlined, and the effects on humans and structures are discussed. It is concluded that residential areas can be safely undermined by conventional drilling and blasting techniques provided certain simple guidelines are followed.

Jan 1, 1987

The 90th Annual General Meeting of The South African Institute of Mining and Metallurgy was held at Kelvin House, Johannesburg, on 19th August, 1987. Dr H. Wagner (President) was in the Chair and declared the meeting open at 16h00. Obituaries The President read out the names of the departed Members as follows: N.M. Airey, F.J. Kisbey-Green, Dr R.A. Pelletier, C.B. Anderson, A.R. Cator, J. van Heerden, P.J. Burman, C.C. Crosson, M. Livingstone¬Blevins, S.T. Firman, V.E. Kisbey-Green, and A.L. Corna. All stood and observed a moment of silence as a mark of respect. Minutes The minutes of the 89th Meeting of the SAIMM, which was held on 20th of August, 1986, were confirmed.

Jan 1, 1987

By C. O. Beale

This, the second and final part of a review on the subject(the first part was published in the March issue of this Jouma/), deals in detail with the 9 copper-producing companies in the Republic of South Africa. These are The Phosphate Development Corporation, Prieska Copper Mines (Pty) Ltd, Black Mountain Mineral Development Co. (Pty) Ltd, Rustenburg Platinum Holdings Ltd, Impala Platinum Holdings Ltd, Western Platinum Ltd, The O'okiep Copper Co. Ltd, Messina Ltd, and Palabora Mining Co. Ltd. The following are described for each company: background, development, geology, mining, concentration, and current situation. The last-mentioned company, being South Africa's largest producer, is dealt with in greatest detail.

Jan 1, 1985

By M. J. Nicol, G. Cromberge, C. A. Flemming

A relatively simple rate equation for the kinetics of the absorption of gold from cyanide solutions onto activated carbon was lI5ed as the basis in the development of a model for multistage carbon-in-pulp and carbon-in-Ieach absorption circuits. The model was used in the prediction of both the steady-state and the transient behaviour of the absorption process, and the results were found to be in reasonable agreement with those observed in an extended pilot-plant campaign. A number of practical implications of the model are discussed, and an assessment is made of the economic consequences of the various process options available for the design of a carbon-in-pulp plant.

Jan 1, 1983

By P. A. Laxen, P. J. van Staden

Alternative procedures for the recovery of gold from old sand dumps are discussed, with emphasis on the use of heap leaching. The modification of material to improve its permeability prior to heap leaching is not currently receiving much attention in South Africa. The channeling of solutions through heaps and the high consumption of reagents sometimes ascribed to heap leaching can, as shown by the results described in this paper, be lessened by desliming of the sand prior to heap leaching and the treatment of the resulting slimes fraction by agitation leaching and carbon-in-pulp. This combined procedure results in a higher overal recovery of gold. Alternatively, the sand can be heap-leached as it is after agglomeration with lime and cement, which improves the mixing and neutralization of the material, as well as lessening the probability of channeling.

Jan 1, 1988

The proceedings of the Centenary Banquet that was held on Friday, 25 March 1994 at The Bal Room of The Carlton at 19:30 follow. Dr H. Scot-Russell The Chemical and Metallurgical Society of South Africa-a forerunner of this Institute-was founded at a meeting held in Johannesburg on the 24th of March, 1894. One of the traditions established early in the life of the Society was the Annual Dinner, which became a major event in Johannesburg's social calendar. It was always attended by people of stature in the industry and in the community, and was usually addressed by a high-ranking Government figure. We are delighted that, on this one hundredth birthday of the Institute, we have been able to continue the tradition. I welcome you, Mr State President, and your charming wife, and we look forward to hearing your address later this evening.

Jan 1, 1994

By P. W. Ocerbeek

The occurrence, properties, and uses of andalusite, and its advantages over other refractory minerals and materials, are discussed. Ore reserves are given for the five producing areas, and statistics on production, export sales, and prices are included to illustrate the growth of the industry since the early 1960s. The mining and beneficiation procedures are described, with special reference to new techniques in concentration and magnetic separation. As fines dumps represent a considerable source of andalusite, possible methods of recovery are discussed. . The outlook for the future appears favourable, and possible competition from other sources and substitute refractory minerals are mentioned. It is concluded that the industry is in a sound position to maintain South Africa's status as the world's foremost producer and supplier of andalusite.

Jan 1, 1989

By W. Peters, W. A. H. Poppmeier

An overview is given of the present state of traditional and new steelmaking equipment and techniques, and one of the direct steelmaking methods that are currently being developed is described. In steelmaking processes, coal is used to supplement the energy input and to reduce iron oxides in the slag. Foamy slag practice is discussed, and the most widely used types of ladle recarburizers, their properties, and manufacture are described. It is concluded that the use of carbon sources, mainly for supplementing energy and as reductants, will increase in the future, but that demands on the purity of the materials will probably become more stringent. If hydrogen were manufactured at a competitive cost, it could become an alternative fuel and reductant in the field of iron and steelmaking.

Jan 1, 1993

By T. M. Evers, R. P. Van Den Berg

Ancient mining in Southern Africa, with reference to a copper mine in the Harmony Block, north-eastern Transvaal T. M. EVERS. B.A. (Birm.) (Visitor) and R. P. VAN DEN BERG. B.Sc. (Wits.) (Visitor) A recently discovered mine on the farms Harmony 24 and 25 in the Letaba district has been investigated archaeologically by T. M. Evers and geologically by R. P. van den Berg. The archaeological investigations shed light on the mining techniques and accompanying metallurgical techniques, while the geological investigations give information on the structure and mineralization of the mine. Comparisons with other investigated ancient workings show that mining was well understood in Iron Age times, before the African peoples had any contact with Europeans.

Jan 1, 1974

By K. R. Vost

"In situ" measurements of the surface heat transfer coefficient in underground airways by K. R. VeST,* B.Se. (Glas.), M.Se. (N.S.W.) (Visitor) Few "in situ" measurements have been made of the surface heat transfer coefficient in mine airways despite the importance of this coefficient in determining the heat flow into the ventilating air. In this paper, the values obtained at various air velocities and the comparisons of these values with theoretical values are given. Examples are also given ofthe errors which would result if rock surface temperatures were obtained by extrapolation from temperatures further into the rock without taking into account the time delay which occurs before a given change in air temperature reaches the points from which extrapolation is carried out.

By J. C. Mostert, P. N. Roberts

Electric smelting at Rustenburg Platinum Mines Limited of nickel - copper concentrates containing platinum-group metals By J. C. MOSTERT Pr. Eng.. B.Sc. (Stellenboseh). M.Sc. Met. Eng. (Fellow) and P. N. ROBERTS Pr. Eng.. B.Sc. Eng. (Rand) (Fellow) The processes involved in the smelting in an electric furnace of nickel-copper concentrates containing platinumgroup metals are described. These are concentrate drying, pelletizing, pellet drying, and flux and pellets proportioning, followed by smelting of the concentrate in a submersible-electrode electric furnace, which is discussed in more detail. The furnace matte is blown in a converter to the white-metal stage and is cast in moulds, whilst the slag is granulated, ground, and floated for recovery of valuable metals and afterwards pumped to the tailing dam.

By J. Meintjes

The measures taken by Rand Carbide Limited from the 1950s to 1976 to control dust emission from the electric furnaces at its Witbank factory are described. A new design of furnace for calcium carbide followed by a dry-fabric filtration plant for the furnace gases was not successful in arresting the dust. A 131 m chimney commissioned in 1968 effectively dispersed the dust-laden gases from both carbide and ferrosilicon production and so brought considerable alleviation. In 1974 a bag-filter dust-collecting plant was successfully commissioned on a 6 MV.A carbide furnace, and this was followed in 1976 by a bag-filter plant on a 46,5 MV.A ferrosilicon furnace. The company has spent considerable effort and money over two decades in trying to combat dust emission, but eventual success had to await technological development.

Jan 1, 1978

By Peter Smith

The construction of one of the world's largest goldrecovery plants to treat run-of-mine ore is progressing on schedule at the President Brand Gold Mine in the Orange Free State. Designed to treat 390 kt per month, the plant will recover 96 per cent of the gold from the ore at a capital cost of 160 million rands in terms of January 1983 money. It will replace the existing gold-treatment installation, as well as provide a 30 per cent increase in capacity. Mintek reports Report M161 Improved recoveries of gold from auriferous calcines and pyrites by fine milling. Report M171 The development of a versatile computer programme for the evaluation of batchflotation results. Report M178 The reduction of chromite in a transferred-arc plasma furnace. Report M179 Optimization of an inductively coupled plasma by the simplex method.

Jan 1, 1985

By R. R. Mankowski, F. J. Cox

Experimental results are presented on the longitudinal atenuation of a kinetic shock wave traveling along a typical mine hoisting cable. Mathematical curve-fiting of the results established these losses to be exponential and tension-dependent. The reflection and power-transmission coeficients of a typical winding drum were also investigated. The degree of penetration of an incident stress wave onto the coil of cable wrapped round the drum is shown to be governed by a second-degree relationship, and is solely dependent on the acceleration of the cable at the cable-drum interface. Although the investigation is limited to the testing of a single hoisting cable, certain qualitative trends that were identified can be generalized and applied to other types of hoisting cable with diferent geometries, elastic properties, and instalations.

Jan 1, 1986