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By Groom P.

The wastage of timber in coal-mines that is caused by decay is very great; in fact, far greater in this country than is generally realized. Mr. E. W. Peters estimates that of the whole wastage of timber in mines in the United States of America, 50 per cent, is due to decay and insects; of this 50 per cent, an overwhelming part is due to decay. The most efficient methods of decreasing this grave loss can be devised only by co-operation of the mining engineer and the scientific expert, and it is partly in the hope of procuring such collaboration that this paper is written. It contains, therefore, a resume of our present knowledge of the decay of wood, and of the economic methods of checking this in mines; but, with a view to improving those methods, it also directs attention to the gaps in our knowledge and the means by which these can be filled by future investigation

Dec 1, 1916

By J. Drzymala, K. L. Wolters, T. Chmielewski, T. D. Wheelock, D. H. Birlingmair

Microflotation tests were conducted with a modified Hallimond tube equipped with a fritted glass disk and magnetic stirrer to determine whether the results would support an equation that predicts a linear relationship between particle size and the reciprocal of particle density in water for a specified flotation recovery in a given time. Data obtained with the tube for either hydrophilic or hydrophobic solids fit the equation satisfactorily. It was also shown that the natural flotability of molybdenite is somewhat less than that of elemental sulphur and that sodium dithionite is a good depressant for sulphurised pyrite. In addition, it was found that the untreated pyrite and galena used in the study were hydrophilic and did not float by particle-bubble attachment.

Jan 4, 1992

By Dobson C. L.

The memoir, presented at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne on 3rd June 1916, outlines the career of one of the Institute's oldest members and past-president 1896-1898, including the improvements he introduced at Harton, St. Hilda and Boldon collieries and his activities with the Institute and the Durham Coal Owners' Association

Dec 1, 1916

By J. A. Franklin, E. Broch, G. Walton

To make the best use of rock core, the mechanical character of the rock should be evaluated concurrently with conventional geological observations. The advent of simple techniques, such as the point load 'nutcracker' test, makes field logging of mechanical properties competitive with sampling and testing in the laboratory

Dec 1, 1971

By S. K. Chaulya, R. S. Singh, B. B. Dhar

Two prominent local species, Dendrocalmus strictus (bamboo) and Saccharum spontaneum (kashi), and two exotic species, Cymbopogon citratus (lemon grass) and Vetiveria zizanoides (vetiver), were selected for growth trials on dumps at Mandaman, Chora, Mudidih, South Balanda and Ghugus. The climate at these sites is dry tropical and the surface soil layer a slightly acid to neutral sandy to clayey loam 10-11 cm thick, impoverished in major plant nutrients. After two years bamboo had grown the most, up to 325 cm in height, and contributed the greatest biomass, 638 g/m2 of plant. The local kashi species had a very good regenerative capacity, which was lacking in the lemon grass and vetiver. The grasses had very good soil-binding capacity and could also provide income if used as cash crops

Jun 21, 1905

By Gibson J.

Written discussion contributions to the paper presented at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 12th February 1916, with Mr. T.Y. Greener, President, in the chair, comprise comments by Kilpatrick W.M., Routledge W.H., Watson J. and Smith W., along with the author's reply. Also briefly noted are the demonstration of two pieces of equipment, an incline chock and a cage arrestor

Dec 1, 1916

By R. J. Gochin, P. Bevilacqua, G. D. Schena

This class of flowsheet-dependent simulators does not replace modular simulators, such as Modsim and Microsim, which are necessary for the assessment of different flowsheets before selection of the most desirable technical option and for investigation of the fine details of unit processes. The system presented here is regarded as complementary, serving in the early stages of feasibility studies as an aid to assessing the convenience and economics of preconcentration; the example used is of dense-medium preconcentration of a barytes-fluorite ore

Jun 13, 1905

By C. T. Shaw

Fur a secure mineral supply position to be maintained in the Fiuropean Community there must be a supply of qualified people in the minerals industries. The education of the people required to run and develop these industries should be a priority in the community. This means that there should be a strong capability in mining engineering education. The mining engineering professors decided in 1990 to get together in a new Society to discuss the problems. The Society of Mining Professors/Societat der Berg-baukunde was formed at a meeting in Austria in October 1990. It is basically a F.uropean Society with a few member professors from outside Europe to keep the Society conversant with trends elsewhere. The objectives of the Society are to see that the mining universities in Fiurope maintain standards and produce enough mining engineers. The present membership of the Society and the work of developing a database of current courses is described. Working from the knowledge base developed, it will be possible to design a 'European' mining degree course. The problems which will have to be addressed have been identified and are described in detail.The paper finally goes on to discuss the other problems that universities are facing, the economic problems and above all the lack of students applying for mining courses across Europe. The help and active participation of the mining industry, if that industry still wishes to employ mining engineers, is identified as the only possible solution to those problems.

Jan 1, 1993

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 I. R. Stevenson, J. G. Dunn, T. N. Smith, L. C. Mackey

An experimental flash reactor has been developed to simulate the operation of an industrial flash-smelter reaction shaft. Four concentrate materials of differing mineralogical compositions were characterised and then oxidised in the reaction shaft. The products were examined by chemical analysis to determine the extent of oxidation and by electron-probe microanalysis to determine the fate of individual particles. This programme of work enabled the influence of mineralogical composition and particle size on the extent of oxidation to be assessed

Jul 1, 1991

By L. J. Barnes, R. O. Koch, J. H. Versteegh, P. J. H. Scheeren, F. J. Janssen

Following two years of laboratory research with bench scale reactors, a 9 m3 experimental process demonstration reactor was installed at Budelco's zinc refinery to treat their underlying groundwater. A 600-fold scale-up was successfully achieved. It has demonstrated that this anaerobic microbial process can remove a wide range of heavy metals and sulphate to the required levels. Extended operation of the demonstration unit has shown that the process is robust, can withstand wide variations in feed composition, rapidly recovers from operational upsets and is easy to start up and shut down. The metal sludge produced can be processed in a metal refinery to recover both metals and sulphur.

Jan 12, 1992

By Eric Forssberg, Vigen Zeng

During mechanical grinding high intensity vibration is emitted that contains information on the mill's operating state. Tests, using a laboratory ball mill, studied the influence of operating parameters on the vibration signature. The parameters studied were: mill speed; powder filling; pulp density; grinding period; and pulp temperature. Vibration signals were detected by an accelerometer, amplified by a vibrometer and recorded onto digital audio tape. A digital oscilloscope converted the signals into IBM-compatible data format. Digital signal processing and multivariate data analysis were carried out with specially developed software. The power spectral density was estimated from the time-domain vibration signal. Four new latent variables were used to describe changes in the vibration spectra. A relationship was established between operating parameters and latent variables which could form the basis of a quick and automatic method of monitoring operating parameters in ball mill grinding.

Jan 4, 1993

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 D. Mireku-Gyimah, R. S. Suglo

Ghana contains auriferous belts which cover 51 800 km2 of its small area of 239 400 km2. From 1493 to 1600 35.5% of the world gold production was from the Gold Coast (renamed Ghana in 1957). This dropped to 8.9% from 1701-1800. For the past fifteen years annual production has averaged less than 2% of the world total. By 1985 only four gold mines were operating, compared with 45 in 1934 and 11 in 1945. Since 1987 Ghana has experienced a boom in gold mining activities. By 1991, 83 new companies had acquired prospecting licences. At least five new companies have started large-scale production. About 650 licensed small-scale mining groups are in operation. The economic and technological factors that have contributed to the decline of gold production in Ghana are discussed. A summary is given of the methods used to mine and recover gold. These cover small-scale workings, dredging, open cast operations and underground mining. The advantages and disadvantages of these technologies and the future of gold mining in Ghana are considered.

Jan 4, 1993

The report of the Annual General Meeting of the Institution of Mining and Metallurgy held on Thursday, 20 May, 1971, in the rooms of the Geological Society of London, Burlington House, Piccadilly, London, W.1, at 4 p.m. (Chairman : M. J. Cahalan, President) includes details of awards and prizes presented to William Justin Kroll, Sir Gordon Colvin Lindesay Clark, John Convey, Evert Hoek, Peter Reginald Dawson and Christopher Michael St. John

Dec 1, 1971

By C. H. J. Beaven, M. P. Jones

Since the various new techniques of automation and computing have enabled vast numbers of mineralogical observations of relatively small samples to be made cheaply and rapidly, the statistical assessment of these measurements has become of vital importance. Much of the theory and most of the procedures of sampling that are used in the mineral industry are based on Gaussian statistics, but modern measuring techniques show that many mineralogical parameters do not necessarily follow the Gaussian distribution function. Consequently, it has become necessary to examine the application of other, more suitable statistical methods in order to derive the maximum amount of useful information from the examination of mineralogical samples. Some of the errors that can be introduced by the use of incorrect distribution functions are discussed and the value of determining the function that is appropriate to the particular parameter that is being measured is shown. Examples are provided of non-Gaussian distribution functions in mineralogical materials that were encountered during prospecting and during mineral treatment operations: a Canadian uranium ore, a Thai tin ore, and gold ore tailings.

Dec 1, 1971

By Winmill T. F.

(Paper presented at the Institution of Mining Engineers' general meeting held in London on 8th June 1916.) The conclusions reached in this paper may be summarized briefly as follows: (1) The method of estimating moisture in coal by determining the loss in weight of a sample heated to 105°-110° Cent, in an air-bath for an hour is untrustworthy, the results so obtained being too low. (2) Dried coal has a very considerable power of absorbing moisture, and a sample, after being dried, must be protected instantly if it is to remain free from moisture. (3) A fairly accurate estimation may be made by heating the coal in a current of dry air at 105° to 110° Cent., and collecting the moisture evolved. (4) In cases in which it is proposed to use the dried coal for any further experiments, the drying must be done in the absence of oxygen, and this can be done simply and quickly by the vacuum method now described

Dec 1, 1916

By I. Garba

The Bin Yauri deposit in the Zuru schist belt of northwestern Nigeria is a vein-type quartz-sulphide-carbonate gold mineralisation hosted by a brittle fault zone. The occurrence of the mineralisation in a contact zone of a Pan-African granitoid was believed to be sufficient evidence of deposition from magmatic fluids. However, studies may now indicate a metamorphic source for the mineralising fluids. A study of rare earth element geochemsitry was used to investigate the nature of the fluid-rock processes involved and identify the sources of the auriferous mineralising fluids.

Jan 12, 1992

By R. B. Scott, J. Hewitson

The paper investigates the historical information relating to spontaneous heatings which have occurred within the area from 1955 to date. From this information the seams most liable are identified and the location within the workings is enumerated, together with the possible reason for the occurrence of the heatings. Details are given of the precautions taken during development, working and withdrawal. Sampling procedures are outlined and the interpretation of the results is discussed. Reference is made to the various types of material and techniques employed in both preventing and combating heatings and examples are given of their relative cost and the operational experience obtained. Special observations are made on the changes in mining techniques and their influence on spontaneous combustion.

May 23, 1905

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