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By T. Guyaguler

An analytical technique using computer-based multiple-regression methods was employed to determine the relation between the dust-producing index and inherent rock properties of typical samples from a coal-producing area, one of the aims being to provide a preliminary predictive tool for practical use. The investigation demonstrated that factors varied in their influence under different conditions, the brittleness:toughness ratio and the hardness being the most significant inherent properties with hardness showing the highest positive correlation coefficient

Jun 13, 1905

By M. G. Fleming, F. Warner, R. W. Boswell, M. J. Cahalan

The annual dinner of the Institution was held at the Savoy Hotel, London W.C.2, on 22 April, 1971. The President, Mr. M. J. Cahalan, was in the Chair; members and guests numbered 320. The toasts of The Queen and Queen Elizabeth The Queen Mother, Prince Philip The Duke of Edinburgh, The Prince of Wales, and the other Members of the Royal Family were proposed and loyally honoured. R.W. Boswell proposed the toast of the Institution of Mining and Metallurgy, the president responded, Professor M.G. Fleming proposed the toast of the guests and Sir Frederick Warner replied

Dec 1, 1971

By P. Danson, D. A. White, S. Bashir

Composite ion exchange materials made of SnO2, TiO2 and MnO2 can be used to remove radioactive contaminants from nuclear waste streams. In several cases their selectivity and capacity are enhanced by mixing hydrous silica into the matrix. MnO2-SiO2 materials are especially useful for a number of reasons, such as their selection of heavy elements over caesium. Distribution constants and determinations of exchange capacities show that in many instances the properties of the composites are better than those of the oxides alone, while the presence of a chelating agent has been found to reduce the uptake of nuclides considerably. Methods are being developed for the bulk manufacture of the materials. Further work on sorption mechanisms is required to explain anomalous results, particularly the variation in exchange capacity for different elements and the ability of the oxides to sorb colloidal material in alkaline solution.

Jan 8, 1992

By K. El-Barawi, Hussein M. Kamal

Chlorination was performed of iron-rich chromite ore from Barramyia, United Arab Republic (UAR), together with its concentrate. The effects of change of grain size, chlorine gas flow rate, time and temperature were studied. The extent and mechanism of chlorination were followed through chemical and structural analyses of the feeds and complete chemical analysis of the chlorination products. By conducting the chlorination process for short periods at 600°C or lower temperatures, products having high Cr-Fe ratios suitable for ferrochrome production can be obtained.

Dec 1, 1971

Discussion continuing that published in Trans.I.MIn.E ., 1915, vol.L, p.449 and 1916, vol.LI, p.166, included contributions by Smith W., McLaren R., Gibson J., McCreath W., Sneddon J.B., Kirkpatrick J. and Mowat D.M. and a written response by Black J.N.

Dec 1, 1916

By J. D. G. Groom

The introduction to a selection of papers from the Minerals '98 professionals' conference, held in London, 24 June 1998 as part of a week of activities supported by 13 professional and trade associations to promote the industry, highlights enthusiastic visitor comments on quarry visits around the UK and outlines the Foresight programme whose key issues were addressed at the conference

Jun 21, 1905

By V. E. Ross

A comparison was made of three methods for determining the contributions of true flotation and entrainment during batch flotation tests. In the first method size-by-size recoveries are measured in both the presence and the absence of a collector, a frother being present in both tests. In the second method the mass of solids and water recovered after a chosen time of flotation is varied by changing the rate of froth removal and the depth of the froth. The third method uses a transfer factor to describe the classification of solids and water, and hence the changes in the composition of the pulp, during a single flotation test. Batch flotation tests were carried out with artificial mixtures of pyrite and gangue, the amount of floated material recovered being calculated according to each of the three methods. The discrepancies betweeen the calculated amounts are analysed in terms of the assumptions that are made for the various methods and the most suitable conditions for the application of each method are identified

Dec 1, 1991

By R. W. Ruddle

The advent of new methods of roasting, “flash roasting and fluidisation”, which are now under development, combined with the use of oxygen-enriched air, may markedly increase the SO2 content of roaster smokes. Skogmo suggests that the production of smokes containing as much as 50 per cent SO2 should be feasible. The use of flash smelting processes may well enable a similar increase in the SO2 content of smelter smokes to be made. In this event the recovery of sulphur would be greatly cheapened and the process might well be much more economic, even if allowance is made for the cost of generating the oxygen

Jan 1, 1953

By A. G. Waters, N. J. Bristow

A comparative study was made of an untreated and a heated haematite ore and a sinter produced from a feed consisting of 100% ore, to study the influence on reduction behaviour of sinter bonding phases such as SFCA (silico-ferrite of calcium and alumina). Under low-temperature reduction conditions the order of increasing reducibility followed that of increasing porosity and surface area but under similar conditions at 900 degrees C the sinter exhibited higher reducibility than the ores even though the total porosity and chemical reducibility of the individual phases were lower. This behaviour can be explained in terms of the higher total porosity of the natural ore at low temperatures and the higher level of fine pores in the sinter at high temperatures due to the presence of SFCA, which acts to support the fine (c.0.1 micrometre) pores created by the reduction process. This leads to the conclusion that the main role of SFCA in sinter during high-temperature reduction is to maintain a high level of fine porosity. Some implications of this work for granule design and sintering practice are discussed

Apr 1, 1991

By L Zhang

The Chinese coal industry is the largest coal producer in the world. The total production in I995 was 1.28 bnt. On the way towards introducing a market economic system, this mature industry is facing major challenges. The main problems are a large surplus of manpower, shortage of current assets and capital, low productivity, high casualties and a huge deficit. This paper discusses the present situation and the future developments in the Chinese coal industry. The current policy can be stated as ‘rapidly developing the state collieries and improving the village and private mines; integrated development to achieve an economic operating scale and encouraging a diversified economy; rapidly exploiting and developing in the North west and South west; promoting productivity and efficiency; welcoming multi-sources and types of investment; setting up coal exchange markets; and the careful control of resources and the environment'.

Jan 11, 1996

By E R. Hassall

Discussiong the importance of minerals and mining, impacts on the environment and remediation, and the need to foster interest in science among young people.

Jan 8, 1997

By A. C. Dunham, Y. D. Drakapoulos, P. W. Scott

The Pt and Pd occur alloyed with copper in small, irregularly-shaped grains, 0.25-5.0 micrometers in maximum dimensions. Grains of unalloyed native copper are also present. The grains are completely surrounded by or marginal to magnetite with inclusions of Ni-Fe-Co sulphides and native Ni-Fe, which is apparently a product of the serpentinisation process. Crystallisation of the Pt-Pd-enriched copper probably occurred at the same time, at low temperature, but the previous form of the Pt and Pd is unknown as no earlier PGE phases have been found. While Pt and Pd minerals are usually important in early-magmatic base-metal sulphides, Pt alloyed with Cu is extremely rare and apparently occurs only very late in the paragenetic sequence. A Cu alloy with Pd dominant over Pt and only minor amounts of other elements appears not to have been reported

Jun 14, 1905

By A. B. Holland-Batt

Two graphical techniques which are commonly used to assess batch separations are analysed in terms of reaction kinetics to provide a more powerful method of evaluation. An alternative and more general approach, based on the selection and application of suitable efficiency criteria, is also presented. The method proposed distinguishes between selection and collection efficiency in flotation and can be used to estimate the degree of liberation in the feed. Two examples are given: table concentration of monazite and ilmenite from a beach sand, and flotation of a pyrite-haematite ore

Dec 1, 1971

By A. Paulin, A. W. D. Hills

The work has shown that packed-bed behaviour can be predicted from the results of single-particle experiments, total reaction times being predicted somewhat more accurately than gas and solid temperatures and gas compositions. A small laboratory packed-bed reactor was built and used to study the decomposition of beds of specially prepared CaCO3 spheres, steps being taken to minimise the effects exerted by the walls of the bed on processes occurring within the bed. Gas and solid temperatures and gas compositions were measured at various points in the bed and compared with theoretical predictions based on kinetic data determined in previous single-particle experiments. The measured solid temperatures and total reaction times agreed remarkably well with the values predicted theoretically. Gas and solid temperatures measured after the reaction had finished at any point in the bed did not agree with the theory. This was because solid temperatures in the bed rose very rapidly once the reaction was completed and the walls of the bed could not be heated at a sufficient rate for their temperatures to rise as rapidly; thus some loss of heat from the bed to the walls was inevitable, and this could not be accounted for in the theory. In addition, the theory did not allow for the conduction of heat within the bed, and this resulted in some further slight discrepancy between the measured and predicted values, particularly after the reaction was completed. Gas compositions measured in the bed were rather scattered, but, even so, they agreed moderately well with the predictions of the theory.

Dec 1, 1971

By A. Policard

The question, of the pathogenesis of pneumokoniosis is very important not only from the social and economic points of view but also from the purely biological. The study of the pathogenesis of the disease leads to fascinating problems of cytology and cytochemistry. Two problems present themselves for examination from an analytical and critical point of view: 1. The first reactions of the alveolar walls to inhaled dusts. 2. The precise nature of the action of mineral dusts.

Jan 1, 1947

By M. Schwartz

Mining in Argentina is diverse in terms of the number of minerals extracted from the country, but also in terms of the varied approaches and attitudes of mining investors and their trust in the country's individual provinces. Laws are discussed, investment attractiveness and taxation.

Jun 1, 2015

By R. Patel, J. Ephraim

The production of titanium dioxide (TiO2) from its minerals such as ilmenite is challenging, and subsequent isolation of titanium from TiO2 is even more difficult because of the metal-oxygen bond strength. Currently, titanium sponge is mainly produced via the Kroll process, which is energy intensive and generates large quantities of waste. A number of international research groups have come up with technologies for the production of titanium metal. However, none of them have been commercialised, because of engineering or economic issues. The team at Bradford have confirmed that ultra-pure titanium powders can be separated from TiO2 powder through metallothermic reduction and are working to scale up the process.

May 1, 2015

By C. A. Pickles

Mixtures of silver chloride and copper chloride are produced during gold refining by the Miller process. A study was carried out into the reduction with iron of a synthetic Miller chloride containing 13.64 mass% Ag and 2.42 mass% Cu. The effects of smelting temperature and time and of additions of iron and borax were investigated. The results were interpreted in terms of metal recovery and quality. Temperature did not have a significant effect on metal recovery above the melting point of the metal product. Borax additions reduced vapour losses and improved metal recovery. With excess iron it was possible to achieve silver recoveries of about 100% and copper recoveries of about 70%. The metal product contained on average 76.1 mass% Ag, 7.5 mass% Cu and 12.8 mass% Fe.

Jan 4, 1993

By R. W. Ruddle

"Besides copper, iron, silicon, and oxygen, a large number of elements may be present in copper ores, the more important of which are zinc, lead, arsenic, antimony, bismuth, selenium, tellurium, nickel, cobalt and the precious metals; impurities of less importance are calcium, magnesium, aluminium, barium, sodium, potassium, manganese, lithium, fluorine, titanium, uranium, vanadium, tin and molybdenum. All of these elements are eliminated to some degree in the subsequent roasting, smelting and converting operations.Information on the elimination of impurities during the smelting of copper is surprisingly meagre, however, rather more information is available on impurity removal during the smelting of the ore in reverberatory or blast furnaces."

Jan 1, 1953

By D. F. Ball, P. R. Dawson, J. T. Fitton

Report of discussion at December, 1970, IMM general meeting (Chairman: M. J. Cahalan, President) and contributed remarks on the paper published in Transactions/Section C (Mineral Processing & Extractive Metallurgy), vol. 79, September, 1970, pp. C189-96, plus the authors' replies. Contributors included Cohen E., Hope B., Wasse D.G., Shakespeare A.G., Burwood D.S., Jones H.A., Dartnell J., Carter G.C., Henderson T.A., Relf G. and Clark S.W.

Dec 1, 1971