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By J. C. David, G. Coetzer

The effect of varying aliphatic, olefinic, and aromatic groups in the N- and S-positions of dithiocarbamates was investigated in the selective and bulk flotation of a mixed copper-lead-zinc-iron ore. Selective and bulk flotation were found to be dependent on the type of functional group, as well as on the position of substitution.

Jan 1, 1989

By P. C. Seligmann

The theory of firing of electric detonators is developed insofar as it affects the design of blasting circuits. Practical values for the firing conditions suited to detonators of local manufacture are tabulated. The design principles of blasting circuits are outlined. This information can be used by mine management to ensure that electric blasting will be done efficiently and economically.

Jan 1, 1979

By G. Coetzer, J. C. Davidtz

The substitution of functional groups in covalent trithiocarbonate collector molecules influences the selective and non-selective bonding of collector molecules to mineral surfaces, as well as flotation efficiency in a mixed sulphide ore. These effects were concluded to be related to the metal-sulphide solubility products and electron densities on the sulphur atoms in the collector

Jan 1, 1989

By M. H. Kirchner

Trackless mining at Thabazimbi Mine by M. H. KIRCHNER*. Pr. Eng.. B.Sc.. B.Sc. (Elec. Eng.}(Stellenbosch). Dip. Mining (Pta.) Certain aspects ?f the' methods used in the exploitation, by sub-level caving, of a wide, tabular, steeply dipping orebody are described, reference being made to the use of modern mechanized equipment. Statistics relating to production and labour, as well as some geological details, are given.

By A. K. Haines

Hydrometalurgy, particularly leaching, is a highly topical subject and always generates great interest in the mineral industry. This was evident right from the start of the organization of the SAIMM Colloquium on Leaching, which was held at Mintek on the 8th and 9th November, 1988. The response to the cal for papers was so good that the Colloquium was extended to two days, instead of the usual one day.

Jan 1, 1988

By G. Paul

The mechanism of nodular crystallisation of graphite in the production of spheroidal cast Iron is not fully understood. The work reported In this paper confirms that in cast iron melts having a high Interfacial tension against the environmental atmosphere, the graphite tends to crystallise in nodules during solidification. The Influence of Interfacial tension between melt and solid graphite is similar.

The 94th Annual General Meeting of The South Mrican Institute of Mining and metallurgy was held in the Gold Room of the Transvaal Automobile Club in Johannesburg on Wednesday, 14th August, 1991. Obituaries The President announced the deaths of the following members of the Institute: Honorary Life Fellow and Past President

Jan 1, 1991

The addition of binder to full plant tailings significantly affects the rheology of a backfill mixture and, consequently, the pressure gradients in the pipeline. The binder increases the yield stress and apparent viscosity of the mixture, and the transition velocity between the laminar and turbulent flow regimes. In a test conducted at a slurry relative density of 1,72 with binder addition, the mixture also exhibited time-dependent behaviour owing to the hydration of the binder.

Jan 1, 1993

By J. D. Koch

A 'project' is defined here as a process in which an idea is developed from its inception until either it is discarded or the product of the idea has been accepted by the ultimate user. The phases in a project, particularly the early phases, are examined, and project organization is described and contrasted with a functional line-management type of organization. Emphasis is placed on comprehensive definition, which is vitally important to the achievement of the goals of time, cost, and quality set for a project.

Jan 1, 1981

By H. L. Monro

CONTRIBUTION BYP.J.D.LLOYD The thought-provoking paper by Monro deserves serious consideration. If he is correct, the practice of selling gold forward should cease forthwith. However, similar arguments may well be advanced against the selling forward of many other commodities, and this runs counter to the success of futures markets worldwide. If, indeed, the practice were basically flawed, then such markets should long since have failed.

Jan 1, 1992

The finite element method of stress analysis is nowadays widely used in the fields of mining, mechanical and civil engineering. This paper presents a short description of the three-dimensional method, in which the elements used are arbitrary hexahedrons. Two examples of the application of the method are presented, namely, calculation of the elastic stress distributions in a coal pillar and in an opencast mine.

By H. T. Clausen

This paper gives a brief review of the main environmental and ecological problems of slimes dams, both those created in the immediate vicinity of the dams and those influencing the region or catchment. Methods of dealing with these problems and influences on existing dams are described. The difficulties encountered in the growing of grass on steep slopes are explained, and, after an analysis of the conditions, a plea is made for flatter slopes on the sides of dams.

Jan 12, 1973

By E. H. van Niekerk

The production of high-strength Iow-alloy (HSLA) steels containing either niobium or vanadium as the principal micro-alloying element is discussed, including recent developments in steelmaking practice that have had a great effect on the development of HSLA steels; strengthening mechanisms, as well as the principles of thermomechanical treatment during controlled rolling on a hot-strip mill; and the results of production heats with various amounts of micro-alloying elements.

Jan 1, 1984

Colloquium And General Meeting - Trackless Mining in Underground Metal Mines A General Meeting and Mining Colloquium on the above topic was held on Wednesday, May 16th, 1973, at Kelvin House. Dr J. P. Hugo (President) was in the chair. The colloquium wasattended by approximately 200 delegates, and was opened by the President at 9.15 a.m. OBITUARIES The President: It is my sad duty to announce the death of the following: W. A. Schwezoff and L. G. S.

By J. E. Furze

World-wide hikes in the oil price and the prospect of future scar cities of liquid and gaseous fuels have given enhanced status to the South African coal industry. It is thus understandable that the colloquium held at Wit bank on 3rd and 4th October, 1979, and organized jointly by the South African Institute of Mining and Metallurgy and the South African Coal Processing Society should have attracted more than 400 delegates.

Jan 1, 1979

By D. L. B. Pollnow

Tinplate, and electrolytic tinning at the Iscor works, Vanderbijlpark by D. L. B. POLLNOW, B.Sc. (Chem.), M.Sc. (Met.), D.Se. (France) The paper first describes tinplate as a product, dealing with its structure and its advantages to the packaging industry. It then describes Iscor's electrolytic tinning line, which is one of the largest Halogen units in the world. Details are given of the process and of the equipment used.

Jan 1, 1977

By J. P. Coetzee

There is an ample supply of all the raw materials required for the future development of the industry, with the possible exception of coking coal. Improved methods of coke production are being developed. It is anticipated that steel production will reach eight million tons per annum by 1980. New techniques and equipment for refining steel will be installed, together with new processing equipment. The most serious problem now facing the industry is the acute shortage of labour.

By P. S. Turner

After a brief account of the differences between the control of underground fires and those on the surface, the paper describes the analogue detection system used on the mines of the Anglo American Corporation of South Africa Limited. The system comprises Spanair gas analysers, Becon combustion-particle detectors, a telemetering system, a surface signal-recording and-processing system, and an alarm system. The use of the system is described and illustrated.

Jan 1, 1982

By D. A. Viljoen

While coal can be used as a chemical feedstock instead of oil for the production of the petrochemical based commodities that are so important to our modern way of life, the impact that coal is going to make on the world-energy scene is without doubt its more important role in the short- to medium-term. After inflation, energy is probably today's most talked-about and controversial economic issue. It is a plentiful supply of energy that has permitted each of us to live a life of convenience that is matched only by the most fortunate of the aristocracy in history.

Jan 1, 1979

By H. Knorre, A. Griffiths, R. Higgins, S. Gos

Hydrogen peroxide is gaining acceptance as a reagent for the treatment of mining effluents containing cyanide. In this paper some of the chemical and environmental aspects of treatment with hydrogen peroxide are discussed, and one way of improving the economics of the process is described. This is known as selective detoxification, which involves the oxidation of the less stable (cyanide) complexes while not affecting the more stable complexes, which contribute very little to the concentration of free cyanide or to the toxicity of the treated water.

Jan 1, 1987