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By G. S. Pauley

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993 (original title: Case-based reasoning can be a catalyst for improvement). A new computer software technology known as Case Based Reasoning (CBR) can be used to produce small decision support systems that are economically viable. This is because the knowledge that they contain can be owned and maintained by their users. A CBR tool has been used to perform a pilot study with Anglesey Aluminium Metal Ltd. The results are encouraging. They suggest that a combination of CBR and participative design and implementation techniques (such as Checkland's Soft System Methodology) can achieve sustainable improvement in mineral processing functions. An explanation is presented of why traditional, rule based systems are often an ineffective way to implement support systems. It is shown that CBR may provide an appropriate technology solution. Methods of achieving sustainable benefit are indicated. The pilot study with Anglesey Aluminium Metal is used as a practical illustration of the development of a CBR application. A review of potential application areas and some observations about the implementation are presented

Apr 1, 1994

By A. T. Iannacchione

Underground mining of stone in the US is increasing, as is the depth of overburden above the mines. Data gathered from mine visits, maps, discussion with operators and numerical simulation have been used to investigate pillar design and recommend safe practice. Many pillars have slender shapes with relatively large adjacent mine openings: width-to-height ratios range from 0.54 to 3.13 and extraction ratios from 0.56 to 0.91. The pillar material is often very strong and average overburden only 80 m, but occasional failure due to excessive local stress has occurred where pillar size had been unintentionally reduced, overburdens were greater than 200 m, width-to-height ratios were less than 1.25 or extraction ratios were greater than 0.83. Pillars with width-to-height ratios of less than 1.5 appear more likely to fail under excessive stress. When width-to-height ratios fall below 1.0, defects such as through-running discontinuities can have a significant influence on stability. Dip, orientation and material properties are also important

Jun 21, 1905

By A. M. Tunstall

Aspects of blast vibrations, damage mechanisms and the influence of rock quality on damage severity are reviewed and results presented from a monitoring programme in which the rock mass rating for six tunnels was determined. The peak particle velocity induced in the tunnels during open-pit blasting was measured and the tunnels were inspected visually for fresh damage after each blast. The results suggest that the quality of rock in which an excavation is situated has an influence on the level of ground vibration to which it can be subjected without sustaining damage. This means that the use of a single limiting value of peak particle velocity, as in the blast damage criteria for residential structures, is not ideal and may result in damage to excavations in poorer-quality rock masses

Jun 19, 1905

By J. H. E. Jeffes, C. Diaz

The heat balance and chemical equilibria involved in the production of blister copper from a chalcopyrite concentrate in a single operation are examined. It appears that two stages—one oxidising and one reducing—will be required. The analysis indicates that on thermal grounds the process is possible with a dry, high-grade chalcopyrite concentrate, if oxygen enrichment to about 30 per cent is used, but that copper losses in the slag will be serious and will require a secondary recovery operation. More extensive data on the activities of copper oxide in slags are required to elucidate this point more effectively

Dec 1, 1971

By W. R. Chambers

A wide variety of mining conditions exists within the South Midlands Area and across this range of conditions more than one half of the mines are highly susceptible to spontaneous combustion. Two thick seams in which the greatest risk exists are described and illustrated. The different heatings which take place are categorized by the locations at which they occur in the mines: additional special cases not easily categorized by location are discussed separately. The discussion for each category of heating follows the pattern of: (i) the reasons why it occurs; (ii) when it arises the means by which it is fought, and (iii) the preventive measures taken in an attempt to avoid its occurrence. Relatively new factors which may affect the incidence of heatings are highlighted and suggestions are made which may assist in reducing the number of incidents in the Area. A new method of continuous sampling, analysis and recording is described and mention made of an original method of interpreting carbon monoxide results with the aid of the computer. The first results from this work show that an early warning is given of an adverse change in trend several weeks earlier than with the present methods. Lastly, suggestions are made about the direction in which research might proceed to assist in reducing the special hazards created by several features inherent in the present methods of mining.

May 23, 1905

By K. C. Dunham, M. Solomon, T. A. Rafter

Sulphur isotope ratios have been determined for 81 sulphides and S and O isotope ratios for 26 barites from the Alston Block in the northern Pennine ore field. In addition, both isotope ratios have been determined for 29 evaporitic anhydrites of various ages from European and Australian localities. The consistency of the sulphate isotope ratios over a wide area of the northern Pennines, and their similarity to values for Lower Carboniferous evaporites, suggests that the sulphate originated from Lower Carboniferous connate waters. It is suggested that these mingled with warm brines rising through granitic plutons beneath Tynehead and Upper Weardale, the aqueous sulphide ion in these brines having a delta34S value of approximately +10 per mille. The delta34S values for the sulphides range from +15.0 to -5.9 per mille and show an outward zoning with higher values in the central fluorite zones and mainly negative values in the outer barite zones. The wide range of delta34S values for the sulphide S is not characteristic of magmatic S and there is no adequate local source in the Carboniferous sediments. It is suggested that formation waters, probably mainly of connate origin, sank down sufficiently deep to become heated above 200°C before rising through Caledonian granite plutons into the Carboniferous sediments, where they spread laterally to mingle with cooler sulphatic connate water. The rising fluids were hypersaline brines carrying F, Ba, Pb, Zn, Cu and S. Temperatures of deposition calculated from galena-sphalerite isotope fractionation are similar to temperatures previously determined from fluid inclusion studies.

Dec 1, 1971

By Winmill T. F.

The previous papers have been concerned only with the atmospheric oxidation of coals from the Barnsley Seam, for which it has been shown that an adequate explanation of the origin and nature of gob-fires can be based on the reaction between the coal itself and the oxygen of the air without the intervention of any other substance. It becomes of importance, therefore, to ascertain how far a similar explanation will hold good for spontaneous heating in other seams, and with this object in view samples including anthracite and lignite have been taken from a considerable number of pits in different parts of the UK (south Wales, Northumberland and Durham, north Staffordshire, Portrush and Ayrshire), some liable to fire, others not. There is abundant evidence to support the commonly-accepted view that spontaneous heating is due to the heat evolved during the absorption of oxygen from the air by coal or pyrites. The quantity of heat produced by the reaction has been measured and it has been shown that the observed rate of heating of a sample of coal agrees with the rate calculated from the heat of reaction and the rate of absorption of oxygen

Dec 1, 1916

By S. G. Tsimas, A. K. Moutsatsou, G. K. Parissakis, M. A. Komiotou

For Greek kaolin producers, a considerable proportion of whose output is from deposits containing more than 4 wt% Fe2O3, the colouring resulting from iron oxide impurity represents a serious problem that necessitates upgrading of the ore to meet commercial specifications. Autoclave leaching with oxalic acid for 1 h at 120 degrees C and 5-6 bar was shown to reduce Fe2O3 by up to 90% without affecting the structure of the kaolin, which maintained its physicochemical properties. The iron oxalate product can either be removed from solution or precipitated as iron hydroxide with recycling of the oxalic acid

Aug 1, 1995

By I. L. Bell

The ironmasters of America had asked the Iron and Steel Institute to visit the USA. The Council decided it was not possible to accept, but Mr. Bell visited; this is an account of his trip. Topics covered include transport, charcoal, coal measures, coal, anthracite, bituminous coal, flux, magnetic iron ore, specular iron ore, limonite, red hematite, clay ironstone, black band ironstone, smelting works, blast furnaces of Pennsylvania, Lake Champlain furnaces, Lake Superior furnaces, Cleveland furnaces, Pittsburg furnaces, Missouri furnaces, and those of the southern states. He goes on to describe Catalan hearths, malleable iron works, Bessemer works, the Blair steel process, and labour.

Jan 12, 1875

By John Craw

This paper has formulated the methods, both medical and engineering, for the control of pneumokoniosis in the haematite-mining industry in West Cumberland, but this is only part of a general service to improve the lot of the worker in these mines, to make him a better and happier workman, and to permit him to enjoy his work and leisure in comfort and good health. This organization has now been functioning for more than ten years and the results are indeed heartening, but it is only as a result of constant vigilance from the mining and medical point of view that such a plan can operate efficiently. The human element and its full understanding is by no means the least of the problems.

Jan 1, 1947

By R. M. Cooper, H. K. Herbert, D. N. Phillips

A study was carried out to determine the effects of adding CaCO3, Fe, Al and CaSi2 to the ladle, rather than to the raw materials, in order to increase the concentration of Ca, Fe and Al in the final product to meet customer specifications at Simcoa's Kemerton plant in Western Australia. LA-ICP-MS, SEM-EDXRA and ICP-AES analysis of samples and controls showed that the technique is suitable for controlling minor element concentrations. Iron was successfully added, while calcium silicide with aluminium proved better than limestone with aluminium for controlling Ca and Al concentrations in the silicon

Jun 19, 1905

The Aredor mine employs conventional dragline methods to exploit alluvial diamond deposits. Production began in 1984 with the policy of mining in the terrraces during the wet season and in the river flats during the dry season. Early production failed to meet predicted grades. A major geological programme to re-evaluate existing reserves was undertaken. This resulted in considerable increases in reserves in the river flats. Many of the reserve blocks included flats on both banks of the Baoule river. Methods of access into the river flats, normally flooded in the wet season, were developed to allow mining throughout the year. River diversions have been the main method used to provide access into the reserve blocks and, most importantly, to remove the risk of flooding. Aredor has carried out six main river diversions with a total length of 12 km. The diversions allowed production planning to be made on the basis of the economic evaluation of the reserve blocks, without undue regard to natural ground conditions or to seasonal factors. The Manning equation was used for the calculation of channel dimensions and gave satisfactory results. The practical aspects of the diversion preparations and flooding prevention are described

Sep 1, 1991

Discussion at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 8th April 1916, on the paper published in Trans. I.Min.E., vol.LI, 1916, p.72-90, included written contributions on size and gauge standardisation by Lupton A., Peck W.R., Dean S., Mayer R.W. and Ashworth J., with the author's written response, and by Bulman H.F. and Brown M.

Dec 1, 1916

By M. J. Howes

The high degree of mechanisation, which is mainly diesel-powered, has a significant effect on heat loads; heat output from this source often exceeds the heat flow from the surrounding rock. The extensive use of diesel-powered equipment also influences ventilation rates and minimum values are necessary to ensure that emissions of diesel exhaust are adequately diluted. Many Australian mines are in subtropical or tropical areas with high ambient wet- and dry-bulb temperatures on surface. This, coupled with the large amount of heat from mechanisation, usually means that refrigeration is required at much shallower depths. A secondary problem is associated with the definition of acceptable thermal environment conditions, which are sometimes based on the assumption of no air movement. This gives rise to very stringent thermal environment acceptance criteria, which, in some areas, would prohibit work on surface, let alone underground

Jun 12, 1905

By B. W. Hester

Report of discussion at January, 1971, general meeting (Chairman: M. J. Cahalan, President) of the paper published in Transactions/Section B (Applied Earth Science), vol. 79, May, 1970, pp. B60-B67, and contributed remarks. Comments were made by Taylor J.T.M., James C.H., Lethbridge R.F. and Heath K.C.G.

Dec 1, 1971

By Fearnsides W. G.

The second part of the paper, presented at the Midland Institute of Mining, Civil and Mechanical Engineers' general meeting held in Doncaster on 27th May 1916, addresses the post-Carboniferous and pre-Permian movements which brought about the partition of the area and gave to the North Midland district its individuality as a separate coalfield. As earth-movements of several ages subsequent to the Carboniferous have played a part in the formation of this particular coalfield, the aim is to elucidate the effects which belong to the post-Carboniferous and pre-Permian Period and to disentangle them from those of later date. This is done by comparing the geometry of the folded surface of one of the more important horizons in the Coal-Measures with that of the surface of unconformity which divides the Permian from the Carboniferous rocks in South Yorkshire, Derbyshire, and Nottinghamshire

Dec 1, 1916

By M. Foguenne, A. van Lierde, P. Henry

Leaching experiments were carried out on a spent catalyst sample with a honeycomb structure, containing 47.5% Ti, 5.8% Mo, 2.7% Si, 2 035 ppm As, 52 ppm Pb and 8.8 ppm Hg. More than 93% of the Mo and As was removed by direct alkaline leaching after grinding to 80% -36 micrometres. The residue contained 0.3% Mo and 60 ppm As. To obtain a TiO2 matrix with 30 ppm As, acid leaching at controlled pH with 90 kg/t Al scrap was followed by oxidising alkaline leaching. Treatment of the direct alkaline leach solution or of the mixed solutions from the two-stage process involved two successive operations: purification by neutralisation with Al(OH)3 addition to raise the Al concentration to 4 g/l, and ion exchange on Amberlite IRA 94 S resin. Whatever the type of solution treated, elution with 200 g/l NH4OH solution gave an eluate of very high purity containing 164 g/l Mo, less than 70 mg/l V and less than 2 mg/l As

Jun 19, 1905

By F. C. Gennari, D. M. Pasquevich

With the gradual exhaustion of natural rutile, there has been extensive research into its synthesising from lower-grade titanium minerals. The removal of Fe from pseudobrookite (Fe2TiO5) by chlorination was studied, using both isothermal and non-isothermal thermogravimetric measurements. Correlation of the results obtained from element distribution maps, scanning electron microscopy, energy-dispersive X-ray analysis and phases detected by X-ray diffraction in the chlorinated samples showed clearly two associated processes. First, the pseudobrookite particles reacted with chlorine and iron was removed selectively as FeCl3(g), leaving a solid residue rich in the TiO2 phases anatile and rutile, separated from an inner layer of unreacted pseudobrookite by a distinct interphase boundary. Second, chlorine allowed TiCl4(g) to form in the reaction bed, where it removed iron from the Fe2O3 crystals as FeCl3(g) and substituted Ti through a pseudomorphic reaction

Jun 21, 1905

By R. Sweennen, A. Vervoort, J. Caers

A case study is presented of the mechanical behaviour of fractures in the Westphalian A and B siliciclastic succession of mud-, silt- and sandstones with intercalating coal layers in the Campine basin of northeast Belgium. Mining ceased in the area in 1992 and a pilot well was drilled to assess the feasibility of methane extraction by hydraulic fracturing. Work was carried out to study the influence of types of cement fill in fractures on the shear behaviour of the rocks by comparison with that of the coal seams. X-ray computerised tomography was used for visual appraisal and selection of jointed rocks before destructive shear testing was carried out. Two major type of veins were found to be present, one cemented with carbonate and the other with kaolinite or kaolinite/carbonate. Uniaxial compressive strength and shear tests showed that differentiation of the two types of veins was vital in evaluating the strength of the sandstones, as cementing of the fractures by rigid carbonate minerals can reinstate the strength of the rock masses to that of the intact material. Kaolinite was more susceptible to plastic deformation than carbonates

Jun 19, 1905

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