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By M. C. Amiri

The plant produces 130 kg slag per tonne of crude steel, to add to the basic oxygen steel-making converter slag stockpile of around 2 500 000 t. The slags contain 1.81% V2O5, which can be rendered water-soluble by salt roasting with NaCl and an alkali such as Na2CO3. Preliminary tests gave less than 3% V recovery from slag under optimum roasting conditions when NaCl, NaCO3 or Na2SO4 was used, but showed that sodium phosphate could make all the V water-soluble when roasted with slag in a ratio of 3:1 at 1 100-1 200 degrees C. Almost complete leaching was obtained within 2 h with water at boiling point. Sodium vanadate was precipitated by acidifying the leach liquor with HCl to a pH of about 2.2

Jun 21, 1905

By D G. Jefferies

This paper covers National Grid's role in the electricity market, the growth of competition in both generation and supply in that market, and the resulting impact on fuel usage, prices and the environment. It also considers other, external influencing factors on the electricity supply industry, as well as the growing trend towards globalization.

Jan 12, 1997

By A. Z. Lang, D. A. Hall

After a brief description of the causes of spontaneous heating and of general preventative methods, a detailed account is given of occurrences of spontaneous heating in the Main Seam (locally known as the 5/4 Seam) at Westoe Colliery. This seam is about 12 feet thick consisting of hands of coal and shale, but only 4 feet 6 inches is worked because of the thickness os strata in water-bearing rocks and the worked section is selected on quality considerations. An advancing longwall face in this seam (2nd South) began to heat after working for six months and ultimately had to be abandoned. By adopting retreating methods and mining narrow panels it has been possible to extract this coal at an excellent rate of productivity. The system of goaf ventilation is important, because the use of a bleed road would have given rise to dangerous conditions in a goaf which of necessity would have contained fallen coal. Preparatory seals were prepared at selected sites so that, if necessary, a panel could be sealed off quickly; these seals are completed as soon as possible (within three weeks) of finishing a panel. A gas sampling system has been instituted which includes daily sampling on the face and in the goaf, and weekly sampling at the stoppings of all completed panels. The coal has now been extracted from this seam for three years without any further difficulties from spontaneous heating.

May 23, 1905

By Tawsaporn Nuchanong, Ian Nichol

Investigations of the dispersion of gold in soils and stream sediments associated with three gold deposits in Thailand indicate the existence of different geochemical dispersion patterns in the three areas, demonstrating the need for the adoption of a variety of exploration techniques. The three gold deposits which were investigated were the Phu Tham Phra-Phu Thong Daeng copper-gold prospect, the Doi Tung and the Huai Hin Lab gold prospects. Overall the investigations at the three localities demonstrate clearly that the chances of exploration success can be significantly enhanced if composite soil samples are analysed to ensure a more reliable estimation of the gold content in soils and if both the 63 micrometre fraction and the field-panned concentrates of stream sediments are analysed because of the variable grain size of the gold characterising different gold deposits and surface environments.

Jan 4, 1992

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 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

By R. G. Siddall, W. Gale

In the UK the development of the science of strata control has been strengthened by a resurgence of interest in the specialism of roofbolting and its associated techniques. The evolution of the theories and practices of strata bolting in roadway stabilisation is discussed. Practical experiences are considered, principally the use of Australian techniques, the relationship between bond strength and annulus and the effects of stress in the ground. Areas of new technology such as cable bolting, injection anchors and on-board bolters are also discussed. The recent advances in computer technology and rock testing equipment and methods have provided the opportunity to simulate ground behaviour under various conditions. Computer modelling developments and the use of techniques to predict ground behaviour are described.

Jan 4, 1992

By D. L. Buchanan, M. J. Jones

In May, 1982, the University of Western Australia in Perth hosted a three-day international conference on nickel sulphides, followed by a ten-day field excursion to the Western Australian nickel sulphide deposits. The conference was arranged by Professor D. I. Groves, C. M. Lesher and Dr. R. E. T. Hill under the auspices of the International Geological Correlation Programme's Projects 161 ("Sulphide deposits in mafic and ultramafic rocks") and 91 ("Metallogeny of the Pre- cambrian"). This volume contains a selection of the papers that were presented at the Perth conference. Most of the papers are related to the nickel sulphide deposits of Western Australia, but contributions with settings in North America, Finland, Vietnam and Southern Africa have also been included.

Jan 1, 1984

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 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 NA NA

In the third of its features on the new owners of the British coal mining industry, Mining Technology reports on the newest company in the field, Midlands Mining.

Jan 2, 1997

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 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 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 P. A. Wright

The note describes the steps involved in the combination of results reported by Shiraishi and Bell in 1968 and 1970 and by Mills and Turkdogan in 1964. Shiraishi and Bell derived from their vapour-pressure measurements an expression for the activity coefficient of tin implying that the miscibility gap in the two-liquid region is symmetrical about the N = 0-5 axis. The limits of the miscibility gap were reported by Shiraishi and Bell and measurements were reported graphically by Mills and Turkdogan. Least-square parabolas are fitted to the transformed results of Shiraishi and Bell and of Mills and Turkdogan for the miscibility gap in the liquid tin-iron system. Back-transformation from these curves gives limits at 1438 K and equations are derived that appear to be a fair average of existing data, although a third term for the activity coefficient equation needs to be investigated

Dec 1, 1971

By M. W. Davies, P. N. Smith

The activity of MnO has been measured in the system CaF2-MnO at 1773 and 1873 K and in the system CaF2-CaO-MnO at 1773 K by the method of equilibration with platinum. Large positive deviations from ideal solution laws have been found, but these became less as the lime content rose. The loss of a volatile component made activity measurements impossible in the CaF2-AI203-MnO system, but the boundaries of a two-liquid region have been measured at 1773 K.

Dec 1, 1971

By H. L. Paterson, R. R. Keays, M. J. Donaldson, D. J. Boyack, M. F. Smith, J. J. Gresham

"Albite-rich sedimentary rocks that contain abundant Fe sulphides occur in the lower portion of the ultramafic sequence at Kambalda and their broadly antipathetic relationship to most of the nickel orebodies is well documented. These sediments generally contain less than 0.1% Ni, but nickeliferous equivalents with 0.3 to >6% Ni occur locally in close spatial association with more typical volcanic peridotite-associated massive, matrix and disseminated ores. Nickeliferous sediments have been mined at several locations at Kambalda but, collectively, they constitute less than 2% of the total Kambalda nickel reserve. The nickeliferous sediments occur both on the ultramafic-footwall basalt contact and within the lower part of the ultramafic sequence, and are usually less than 5 m thick. They are commonly finely laminated rocks with a cherty appearance, composed essentially of layers of albite+quartz±amphibole, alternating with pyrrhotite+pentlandite±pyrite layers. Some contain a minor amount of carbon. The sediments are only of ore grade (> 1% Ni) immediately adjacent to massive Fe-Ni-Cu sulphides, which are interpreted as normal magmatic ores on the basis of geochemistry and the presence of distinctive ferrochromites. The nickel content of the sediments decreases to background levels (<0.1%) within about 20 m of the massive sulphides. In most locations the massive sulphides clearly have been emplaced tectonically within or adjacent to the sediments, which are commonly highly deformed. Typical nickeliferous sediments contain about 1% Ni, 0.1% Cu, 0.1% Zn, 400 ppb Pd, <0.2 ppb Ir and 10-200 ppb Au. They have lower Ni/Cu (average 10), higher S/Ni (average 6) and higher S/Se (average 11 200) than associated massive sulphides (average 40, 4.8 and 7400, respectively). The Pd/Ir ratio of the nickeliferous sediments (typically > 1000) contrasts markedly with that of associated massive sulphides (average ca 16).The high Pd/Ir values are similar to those which have been reported for hydrothermal Fe-Ni sulphides and barren sulphidic sediments of probable volcanic exhalative origin. They preclude a direct magmatic origin for the sulphides in the nickeliferous sediments, though S/Se and S isotope data indicate a magmatic source for the sulphur. The restriction of nickeliferous sediments to within about 20 m of normal magmatic sulphides and the lack of a widespread Ni dispersion halo suggest local redistribution of originally magmatic Ni. This probably occurred by diffusion and hydrothermal mobilization during deformation and amphibolite-facies metamorphism. Although not totally ruled out, a volcanic exhalative origin for the Ni seems unlikely."

Jan 1, 1984

By J. P. Rees

Describes methods of dust-sampling such as weighing the dust caught on cotton-wool, the sugar tube, konimeter, circular konimeter and the thermal precipitator. Covers the work of mine dust inspectors, the Miners' Phthisis Prevention Committee and the Chamber of Mines Dust Department.

Jan 1, 1947

By E. J. Bolitho

"The paper covers the activities of the Government Miners' Training-Schools. It argues that its success is proved by the steady demand for miners trained at the Schools; by the large numbers of ex-apprentices who hold responsible official positions in the industry; and bv the probable expansion of the organization in the near future to meet the never-ending call for trained personnel."

Jan 1, 1947

By P. A. Rossouw, G. A. Fourie

The correction to the paper published in Trans. IMM A, vol.105, 1996, p.A162-A165 stresses that figs. 4 and 5 had been interchanged, reproduces them with their correct captions for clarity and encourages readers to comment on the Delft proposal

Jun 19, 1905