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By R. Vikram

IMAGES (Integrated Mapping Applications Graphical Evaluation System) is a computer graphics system developed by British Coal for mine planning. The objectives of the system are to increase the profitability of mined coal through a combination of direct and indirect benefits. The system is flexible and can be used in part or in full at a mine as a stand-alone system or as a remote location of a central corporate system.

Jan 12, 1992

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 W. R. Donaghue, R. L. Robinson, C. Scott

Whilst spontaneous combustion has never been considered a major problem in south Durham, certain collieries in the area have a history of heatings and precautions are essential. Three collieries are affected - Shotton, Vane Tempest and Seaham - and in the case of the last two, there are huge areas of high quality coal to work under conditions where spontaneous combustion is a real hazard. The seam being extracted has an immediate roof in goaf left by the incomplete extraction of a contiguous seam worked before the turn of the century. The presence of residual coal stocks and old roadways and cavities adds to the difficulty of preventing unwanted air movement. The main preventive measures adopted are the construction of airtight gateside packs and the use of sprayed surface coatings in the gate. Sampling systems and sampling points are described and, in particular the field of continuous monitoring from the surface is examined. The resulting possibility of a quantitative as well as qualitative assessment of the preventative measures required is discussed.

May 23, 1905

By G. G. Lambert

The paper traces the pattern of spontaneous combustion in the workings of what was originally Hemsworth Colliery, but since July 1967 is now part of South Kirby Colliery. Examination is made of the Barnsley Seam sections and the part played by the top section of the seam as it comes in close proximity to the main seam. In this area of the colliery nine mechanised faces were set away between the years 1953 and 1968, every one "fired" at the pillar edge and six "fired" at the face line when production had ceased. The paper deals with the different preventative measures used, from sandbag walls, cement injections, spraying with polyurethane, until finally using Mandoseal as a sealant. Since the latter method was first used, the last three faces worked in this particular area were all salvaged completely, without any sign of a heating developing.

May 23, 1905

By T. T. Chen, J. E. Dutrizac, C. Canoo

The calcine consists principally of ZnO and ZnFe2O4, which occur as banded and porous grains, together with lesser amounts of Zn2SiO4, Zn-Fe-Pb silicate, sphalerite, quartz, PbSO4 and Fe2O3. Al is present in solid solution in most of the Fe-bearing phases and also as residual aluminosilicate minerals from the original concentrate. Si occurs mostly as Zn2SiO4, Zn-Fe-Pb silicate and as residual silicate minerals. As is commonly found in the ZnFe2O4, Fe2O3 and Zn-Fe-Pb silicate phases. The major As carrier may be calcium arsenate particles less than 1 micrometre in size which are dispersed throughout the calcine. The neutral leach residue consists mainly of ZnFe2O4 and precipitated masses of iron gel-silica gel. Lesser amounts of ZnO, Zn2SiO4, Zn-Fe-Pb silicate, PbSO4, sphalerite, Pb-K-jarosite and basic zinc sulphate are also present. Al occurs in minor concentrations in most of the Fe-bearing phases and in the Zn-Fe-Pb silicate. The residual aluminosilicates are also an important Al carrier. The major As carrier is the precipitated iron gel-silica gel phase, but some As is also present in the Zn-Fe-Pb silicate, ZnFe2O4 and Fe2O3 phases. Silicon is divided about equally between the iron gel-silica gel, Zn2SiO4, Zn-Fe-Pb silicate and residual silicate minerals. The weak acid leach residue is generally similar to the neutral leach residue except for its reduced content of ZnO and basic zinc sulphate.

Jan 4, 1993

By D. C. Cooper, P. M. Green, J. A. Plant, P. R. Simpson, A. J. Reedman

Paper presented at the 28th International Geological Congress held in Washington DC, July 1989 (International geochemical mapping sessions). The Grampian Highlands and English Lake District evolved as part of the American and European continental plates, respectively, and were separated by the Iapetus Ocean until they were tectonically juxtaposed during the late stages of the Caledonian orogeny. The similarity in the controls of the distribution of gold pathfinder elements and gold mineralisation in the two regions thus provides important information for understanding the genesis of gold deposits in comparable tectonic settings elsewhere. The data presented are inconsistent with models that invoke a juvenile source of gold or its pathfinder elements. Instead, they support a model whereby gold and its pathfinders were initially concentrated in volcano-sedimentary sequences in rapidly subsiding, tectonically controlled basins and in associated volcanic rocks. Remobilisation and mineralisation occurred subsequently, probably as a result of an increase in oxygen fugacity associated with the influx of granite magmas into the crust and the establishment of hydrothermal convective circulation systems

Jul 1, 1991

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 NA NA

A round up of recent industry matters. Davis Derby acquisition of Safecom UEP Ltd. Record Output by Longannet Mine.

Jan 7, 1997

By M. D. Pritzker

Shrinking-core models are used to describe the physico-chemical processes that are associated with many metallurgical gas-solid and liquid-solid reactions. The models can be used to evaluate rate constants and effective diffusion coefficients from experimental data. This work generalises the model for diffusion through a product layer to cases where the transport of more than one species is rate-controlling

Jul 1, 1991

By W. S. Fyfe, G. V. Albino, Ekawat Sitthithaworn

The mineralisation is associated with a composite diorite to quartz monzonite stock of Permian to Triassic age that intrudes Devonian carbonate strata. In the intrusive rocks it is associated with potassic alteration and in the carbonate wall rocks it is hosted by prograde garnet-rich and retrograde epidote-rich skarn. Both porphyry and skarn mineralisation include disseminated and fracture-controlled mineralisation, the latter probably accounting for the major part of the contained minerals. Copper, gold, silver and zinc are strongly positively correlated within the mineralised zones, although there are small differences in metal ratios between the different ore types; molybdenum appears to be negatively correlated with copper and gold. Ore minerals include chalcopyrite, magnetite and pyrite in porphyry-type mineralisation and bornite, chalcopyrite, pyrite, magnetite and lesser haematite in skarn.

Jan 12, 1993

"Prior to the publication of the General Report of the Miners' Phthisis Prevention Committee of South Africa in 1916 little attention was paid to the dust hazard and the necessity for its suppression in the underground workings of the Broken Hill mines. Such precautions as were observed for the elimination of dust were related rather to the prevention of lead poisoning, which, in the early days of Broken Hill when large tonnages of lead carbonate ore were being won, was rather prevalent. Ventilation and hygiene followed the general practice in this and most foreign countries.This paper covers incidence and action since 1918, considering medical aspects and operating aspects. "

Jan 1, 1947

By NA NA

Listing safety award winners, £I43M has been added to proceeds from coal privatisation in the year to March 1997, bringing total revenues to over £1.3bn, some company news in brief.

Jan 8, 1997

By ed. comp., S. H. White, A. J. Naldrett, P. R. Simpson

Peter Simpson's introduction, Tony Naldrett's concluding remarks and discussion by Prof. White of D.M.A. Flight's report of the proceedings are presented from the conference held in Keyworth, UK, in April 1992

Apr 1, 1995

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 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 NA NA

Stamler Corporation manufactures of mining machinery and material handling equipment specialising in Feeder-Breakers to the mining and quarrying industries.

Jan 9, 1996

By Fearnsides W. G.

The map shows the sites of collieries and important boreholes in the district, with approximate underground contours of the pre-Permian surface of the Coal-Measures and of the Barnsley Bed

Dec 1, 1916

By L. R. Chimimba

"The Trojan nickel deposit occurs within a pile of ultramafic lavas subjected to a lower amphibolite grade of metamorphism. The lavas form part of the Upper Greenstones (Bulawayan Group) of the Mazoe greenstone belt. The nickel mineralization occurs as disseminated, massive and near-massive sulphides. The massive and near-massive ore occurs along the basal contact of the serpentinite units and is overlain by the more abundant disseminated ore, which occurs within the serpentinite. The main sulphide minerals are pyrrhotite. pentlandite and chalcopvrite. Minor amounts of millerite and pvrite are present. The Ni : Cu ratio in all three types of ore averages 15:1.The intercumulus nature of sulphides in the near-massive ore and similar textures occasionally seen in the disseminated ore indicates a magmatic origin of the mineralization. The basal position of the near-massive and massive ore suggests that the sul­ phides settled out under gravity during the emplacement and crystallization of a peridotitic magma. The deposit has been deformed and some of the primary massive ore has been remobilized into veins and breccias. The disseminated mineralization now occurs mainly as blebs of sulphides intergrown with silicate minerals or as stringers of sulphides between foliation planes in the serpentinite."

Jan 1, 1984

By J. R. Hammond, I. C. Herbert

Report of discussion at October, 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, June, 1970, pp. C128-36 and introduced by I.C. Herbert. Contributors were von Struve G., on the application of balling discs and the use of basic additives; Young P.A., asking for details of the drying, grinding, balling, induration and specification testing equipment and processes; Davison J. on pellet swelling properties and Carter G.C. on disc operation, refractories and green ball properties.

Dec 1, 1971

By J. C. Loretto

The philosophy and detail of mill design in developing countries, where it is frequently difficult to obtain experienced, qualified supervision to operate the plant, are discussed. The resulting design suggests the desirability of simple units, with maximum visibility of equipment operation and material movement, which allow the minimal technical supervision to see the plant conditions prevailing. Information on plant conditions during periods of lesser supervision can be provided by the use of simple, low-maintenance recorders. Where the mill is intended for operation in a developing country, it is insufficient for the flowsheets and plant layouts merely to be drawn: the process metallurgist must pay meticulous attention to details that could ordinarily be left to the design detailing group. The design of this type of mill requires a knowledge of human engineering—of the type of individual who will operate and supervise the plant; probable changes in personnel should be taken into account. Details are suggested for coarse-ore handling, screens, feeders, secondary and tertiary crushers, conveyors, dust collecting, fine-ore feeding, grinding mills, conditioners, flotation, thickeners, filters, reagent systems, sand pumping, sampling, instrumentation, safety and construction

Dec 1, 1971