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By T. A. A. Quarm

The concept of a continuous zinc smelting process which employs submerged combustion of coal char for both heating and reduction is described. An estimate of the results of smelting a marmatitic zinc concentrate indicates that both the operating and construction costs would be lower than those incurred in processes now in commercial operation. The results of smelting a complex zinc-copper concentrate are also estimated, but no simple commercial process exists with which they can be compared

Dec 1, 1971

By B. H. Smith

"Most of the discoveries of nickel sulphide deposits in Western Australia have followed the search for gossans. The chances of further discoveries depend on improving our understanding of the cover of strongly leached and transported materials that obscure approximately 85% of the area of the Yilgarn Block that has nickel sulphide mineralization potential. The lateritic profiles that are observed on the Yilgarn Block today were formed over a period of more than 100 m.y. of warm and humid climates. This lateritized land surface has been preserved by induration during subsequent arid climates as well as by the structural stability of the Yilgarn Block.In geochemical surveys of lateritied terrain samples have to be taken from at least the saprolite zone usually by drilling so that confident predictions can be made of the significance of analytical data. Account must be taken of the mineralogy of samples, as well as the nature of the horizon of a laterite profile that is being sampled, owing to the concentrating effects on trace elements of Fe and Mn oxides.Multivariate techniques have been applied successfully to analytical data in gossan recognition when textural evidence is ambiguous. Pathfinder geochemistry has also been used in gossan recognition and the most significant recent advance has come from studies of platinum group metals in nickel sulphides and their dispersion during weathering."

Jan 1, 1984

By D G. Oldfield

Pall has developed and supplied to several airlines cabin air libers to provide clean air for passengers and crew in flight, while reducing airline operating costs. Most of today's modern commercial passenger aircrafts employ cabin air recirculation as a means of reducing operating costs. With large numbers of passengers being subject to an increasing proportion of recirculated air for hours at a time, the matter of cabin air quality, with particular respect to the health effects on passengers and crew, has to be addressed. Commercial pressure will ensure that the airlines and aircraft manufacturers will not revert back to the total fresh air systems of the 1960s and 1970s. In fact, feasibility studies are already being undertaken to look at increasing the proportion of recirculated air to 80% and above. With the application of specialist nitration technologies. Pall is able to ensure that the requirements for economy are met whilst ensuring that the air is effectively rendered as 'fresh air’ each time it is recirculated.

Jan 9, 1996

By N. Djordjevic

It is commonly accepted that the strength of rock measured from small samples tends to give unrealistically high estimates of the strength of larger samples, in situ blocks of rock or the rock mass in situ. The Weibull theory of the statistical strength of material provides a possible means for calculation of the strength of large rock volumes, based on the routine testing of small samples. Application of the Weibull approach to estimation of the strength of Moura coal showed an encouraging agreement with experimental results and the method was also applied to hard-rock andesitic and porphyry ore from Bajo de la Alumbrera, Argentina

Jun 21, 1905

Discussion of the paper presented at the Manchester Geological and Mining Society's general meeting held in Manchester, April 11th 1916, with Mr. Leonard R. Fletcher, President, in the chair, included questions asked and points for discussion raised by Bramall V., Paton J.D., Fletcher L.R., Siddall F.N., Stoker A. and Stone T., in particular on how to eliminate dust

Dec 1, 1916

By G. D. Nicholls

There have been very few attempts to isolate the various factors that contribute to the overall imprecision of geochemical analytical procedures, due in part to the difficulty of distinguishing between them. The technique of spark source mass spectrography permits a ready distinction between the contributions to overall precision from sampling error and instrumental and other errors. With conventional methods of sample preparation for this technique sampling difficulties are responsible for 80-90 per cent of the overall imprecision. Examination of the probable location of the major difficulties in sample preparation indicates that the preliminary stage of grinding, mixing and extraction of a first aliquot (about 1/100 of the original sample) is generally perfectly adequate. The difficulty lies in the subsequent stages of sample preparation. Dry mixing techniques are unlikely to give good precision if the sub-samples actually examined by the analytical technique are less than 10 mg in amount. Solution techniques are less prone to sampling difficulty. Fusion techniques, unless conducted with great care, can produce more difficulty than dry mixing. Sample preparation is critical to the success of many analytical procedures. Selection of appropriate sample preparation techniques requires just as much care as the selection of techniques for the actual analysis.

Dec 1, 1971

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 G. Richards

Mines are facing fresh challenges over how they deal with the huge quantities of water consumed. industry analyst Frost and Sullivan, demand for treatment equipment and services alone is expected to be worth US$3.6bn by 2016, while a report by consultancy Bluefield Research estimates that the total mine water market - which includes water infrastructure such as reservoirs, pipelines and dewatering systems as well as the equipment and services - will be worth US$17bn by the end of 2019. Methods of water decontamination are described.

May 1, 2015

By Hickling G.

Discussion at the Manchester Geological and Mining Society's general meeting held in Manchester, February 8th 1916, with Mr. Leonard R. Fletcher, President, in the chair, of papers previously published in Trans. Inst. Min. Engrs.,1915, vol. L, p.322 and p.328. Included are a written contribution by Ollerenshaw W. and oral discussion by the author, Gerrard J., Paton J.D., Smith S.A., Stephenson H., Dixon H.O., Pickup W., Fletcher L.R. and Atherton H.S.

Dec 1, 1916

By Le Thac Xinh, van Chu Nguyen

In northern Vietnam Ni-Cu sulphide deposits associated with ultramafic rocks are located in several continental rift zones of Permo-Triassic age. In recent years a number of ultramafic bodies have also been discovered in southern Vietnam, but detailed work on sulphide occurrences within these bodies has still to be undertaken. A brief description is given of some N i-C u sulphide deposits that are located in the northern part of the country. Of the depos­ its that have been examined in any detail, those in the Takhoa region are of the greatest economic interest. Ni and Ni-Cu sulphide bodies have, however, also been found in association with the ultramafic rocks.

Jan 1, 1984

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 J. P. Ress

In 1903, seventeen years after mining of the Witwatersrand gold-bearing reefs started, the findings erf the Miners' Phthisis Commission (Transvaal) resulted in the initiation of measures with the object of controlling dust production. The substance of these measures was as follows: Removal of persons from places where they would be exposed to blasting fumes; use of water to suppress dust made in drilling and in other operations; supply and control of air to working-places; filtration of dusty air; and determination of the amount of the dust in the air. Broadly speaking, progress in dust control has followed these four lines with increasing success as the nature of the problem has become better known. Complete success has not, however, been achieved, partly because increasing mechanization of mining has intensified the problem and partly because the application of these measures is not infallible, being subject, in many cases, to human control. A brief summary of the development of these measures will lead to a description of present-day practice.

Jan 1, 1947

By A. Policard

The bodies of mammals possess a very efficient mechanism for ridding themselves of inhaled dust. When the lung is healthy this mechanism works very well, and dust is quickly and completely expelled from the lung either by the respiratory tract or the lymphatics. The mechanism, however, is easily upset, and slight alterations in the condition of the ciliated epithelium or the circulation of lymph are sufficient to interfere with it, therefore the second mechanism comes into play and the dust is fixed and immobilized in some part of the lung. This, however, is not a real cleansing process, since the lung becomes a dust-trap, and may become'pneumokoniotic. The mechanism is protective at first, but later, when the accumulation of dust is considerable, it gives rise to trouble. The lung cannot become, so to speak, a physiological dust-trap, and still retain its normal structure and function; pneumokoniosis begins, which is essentially a disease due to the mechanical presence of large amounts of inert foreign material.

Jan 1, 1947

By V. Distler, E. F. Stumpfl

Paper presented at the IAGOD international symposium on mineralisation related to mafic and ultramafic rocks held in Orleans, France, 1-3 September 1993. The massif contains large chromite bodies of "Alpine-type", ophiolitic affinity. Orebodies reach thicknesses of 150 m and sizes of more than 150 000 000 t chromite ore with average grades of 55-60 wt% Cr2O3. Chromites in the Main ore field are low-Al, high-Cr spinels which exhibit some variation in their Mg-Fe distribution. This differs markedly from high-Al spinels in peridotite host rocks and in narrow chromite pods which occur in the western and northern parts of the massif. Chromites carry silicate inclusions, often hydrous silicates such as amphibole. Chromites in massive chromitites contain micron size inclusions of platinum group minerals (PGM). Composite grains containing two PGM and, occasionally, a hydrous silicate are common. Os-Ir alloys rimmed by PGM sulpharsenides occur in narrow serpentine veinlets that cut chromite and are evidence for the reconcentration of PGE concomitant with introduction of As, probably during serpentinisation. Whole-rock PGE contents are highest in massive chromitites of Diamond Pearl mine (totals of 500 ppb). Chondrite-normalised PGE patterns of chromitites show negative slopes which are typical for ophiolitic, podiform chromitites in mantle sequences. The PGE patterns of host rocks are flat and rather depleted compared with those of chondrites and chromitites. Petrological data from unaltered host peridotites suggest a high temperature overprint leading to sub-solidus re-equilibration of olivine and spinel and to the growth of pargasitic and edenitic amphiboles

Jun 16, 1905

The author's written response to previous discussion of his paper published in Trans. Inst. Min. Engrs.,1915, vol. L, p.51, discussion p.431, was presented at the Mining Institute of Scotland's general meeting held in Edinburgh on 12th February 1916 with D.M. Mowat in the chair

Dec 1, 1916

By Winmill T. F.

Among the various theories proposed to account for the spontaneous ignjtion of coal, one which has at times been very strongly held is that the initial heating is due to the oxidation of iron pyrites. From the results described in this paper, it is possible to calculate roughly the rate of spontaneous heating of a specimen of finely-divided pyrites, on the assumption that all the heat developed is used in raising the temperature of the pyrites, and that none is lost. It is clear that where finely-divided pyrites occurs in considerable proportion among coal, it may be the chief factor in originating combustion, but that pyrites can only be the cause of a heating when it is present in considerable proportion, and in a very finely-divided state

Dec 1, 1916

By Mowat D. M., Louis H., Smith W. Mackey W. M., Dron R. W., Ellison C. C., Winmill T. F., Kerr G. L., Haldane J. S., Ashworth J., Garforth W., O'Shea L. T.

Discussion of Winmill's paper, including various anecdotal examples, is presented together with the author's response; topics included: the need to distinguish cubic pyrites from the rapidly decomposing rhombic form known as marcasite; the effects of moisture content in the coal and air; the possible effect of pressure; the heat insulation resulting from heap/stack size; and the means of determining pyrite and moisture contents

Dec 1, 1916

Jan 1, 1947

By Fearnside W. G.

Further discussion at the Midland Institute of Mining, Civil, and Mechanical Engineers' general meeting held in Leeds, March 21st, 1916, with T. Beach, vice-president, in the chair, of a paper published in Trans. Inst. Min. Engrs., 1915, vol. L, p. 573 and discussion vol. L., p. 109 and 608, comprised a brief written contribution by Faulds A.

Dec 1, 1916

By Haldane J. S.

Discussion of a paper presented at the Institution of Mining Engineers' general meeting held in London on 8th June 1916 included oral contributions by Louis H., Mowat D.M., Lupton A., Bailey T.H., Blackett W.C. and Gerrard J., and written contributions by Collis E.L., Carlow C. and Wilson W.B., with the author's oral and brief written responses

Dec 1, 1916