Search Documents

By L. J. Barnes, R. O. Koch, J. H. Versteegh, C. J. N. Buisman, P. J. H. Scheeren

Several water treatment options have been studied and piloted. A process based on activity of sulphate reducing bacteria combines sulphate removal and heavy metal removal in one process step. The anaerobic bacteria reduce the sulphate to sulphide and consequently metal sulphides will precipitate. The final design for the commercial scale plant is described.

Jan 12, 1992

Discussion following the presentation at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 8th April 1916, included the author's introduction, written contributions by Bedson P.P., Gregory T.W.D. and Morgan J.D., oral contributions by Louis H., Greener T.Y. and Severs W., and the author's reply

Dec 1, 1916

By Dean S.

Further discussion 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, of the paper published in Trans. I.Min.E. vol.L, 1915, p.179 and 388. Written contributions to discussion included Mr. Dean's reply to earlier discussion (p.35-44), further written contributions by Tate S. (p.44-54) and Brown E.O.F. (p.54-56), and oral comments by Hare S., Merivale J.H., Greener T.Y. and Tate S. Particularly debated were the causes of the difference in output between American and British coal miners

Dec 1, 1916

By F. Boudreault, M. J. Scobie, J. Szymanski, C. Hendricks

The development of new stoping methods and more effective control over dilution, recovery and fragmentation depends on improved accuracy in blasthole drilling. The mechanisms and factors which control accuracy are poorly understood. Canadian blasthole stoping and the practices adopted for monitoring and controlling drilling accuracy are reviewed. The techniques and problems associated with blashole set-up and trajectory surveying are discussed. Four new blasthole trajectory survey systems are evaluated on the basis of their performance in recent underground trials. Conclusions are drawn as to the technological developments required so that more precise control over drilling accuracy can be achieved.

Jan 12, 1992

A study of the thermodynamic properties of magnesium chloride ammines was carried out with the ultimate objective that the thermal decomposition of the hexammine MgCl2.6NH3 may prove successful on a commercial scale for the manufacture of anhydrous magnesium chloride, which is required for the efficient electrolytic production of magnesium. The experimental data are presented in the form of an equilibrium diagram that aids the understanding of the conditions associated with the thermal decomposition of ammines

Jun 13, 1905

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. J. Burdon, Anthony Caplan

"(1) The radiological appearances of pneumokoniosis on the Kolar Gold Field is described in detail. The characteristic abnormality is the. presence of a diffuse, fine annular and punctate mottling. (2) The frequency of symptoms could not be determined with any degree of accuracy, but it is believed that symptoms are absent and there is no incapacity until profuse radiological mottling is present, i.e., after long exposure to dust. (3) There is an increased predisposition to tuberculosis, which, if it occurs, affects the prognosismost unfavourably.(4) Pathological examination shows that the radiological mottling is due to the presence inthe lung of numerous small dust-cdll aggregates (up to T5 mm. in dia.) deposited around the smaller bronchioles and blood-vessels.(5) The dust-cell aggregates are relatively acellular but when tuberculosis is superadded thereis an excessive cellular and fibrotic reaction.(6) The difficulties of defining the radiological and pathological appearances of early pneumokoniosisare discussed.(7) The incidence of pneumokoniosis in 7,653 workmen with 5 or more years’ undergroundservice was 43-75%, but it is suggested that in future the incidence will be appreciably lower.(8) The methods of- dust production and the chemistry of mine dust are described. It isshown that the free silica-content of air-borne mine -dust is relatively low.(9) The aetiology'of the pneumokoniotic lesion is discussed."

Jan 1, 1947

By D. G. Skinner, M. SC. Griffiths

"The natural difficulties associated with the size evaluation of dusts render absolute measurement difficult, or indeed, impossible. Assuming that the desirability of gravi­ metric sampling be conceded, it appears likely tha,t the most suitable means available for physical evaluation are the method of total turbidity measurement, to give a con­ ventional value for specific surface, together with microscopical examination, the great merit of the latter being that in the hands of an experienced operator, semi-quantitative discrimination between coal and other particles is possible.The pipette method, as modified by Fryer, probably-deserves more attention than it has received up to the present. Whatever method is used, it is recommended that in view of the lack of medical knowledge, as much information as possible should be obtained with reference to the total mass concentration, the surface area of the total dust,' and the mass and area of the particles below 5μ in size."

Jan 1, 1947

By I S. Lowndes, K. Moloney

Diesel powered equipment is currently used extensively in mining and tunnelling operations around the world due to its mobility, flexibility and through selective application to enhance productivity. However, the increased use of diesel equipment has exacerbated the pollutant load (including heat, humidity, exhaust gases and particulates) placed upon the environmental systems of many underground operations. This expansion in the use of diesel equipment has prom pted researchers to evaluate m easure ment and control technology. This paper reviews the recent research conducted in various countries.

Jan 10, 1996

By R. F. Bell, Schultz

The paper briefly discusses the nature of spontaneous heating in mines in the Doncaster area, in the period immediately before 1967 and steps taken to prevent and treat such outbreaks. The changes that led to the increased rates of advice of Barnsley Seam faces since 1967 are listed and the effects of these increased rates on the frequency and location of spontaneous combustion are discussed. The change in methods of control required by the increased rate of advance of the faces and the changes in location of outbreaks are described. Some typical heating situations are evaluated. The methods described include the use of air sealants, water gels for filling of voids in wastes, the balancing of pressures across heating areas by pressure chambers, booster fans, and the resiting of air separation doors, and the sealing of air-ways by flooding. The authors discuss the influence of mine layouts on the risks of spontaneous combustion and advocate that future plans should be designed to limit the number of districts at risk when heatings occur.

May 23, 1905

By M. Dobias, N. Mayor, J. Lillo, A. Gonzalez, R. Lunar, R. Oyarzun

The central domain of the Spanish Central System contains a series of Ba-(F)-(base metal sulphide) hydrothermal vein deposits that are hosted by adamellitic granitoids. Fluid inclusion and sulphur isotope data suggest that the mineralisation was formed by low-salinity hydrothermal solutions that incorporated fluids, metals and sulphur from a magmatic source. Mineralisation occurred in two main stages; a first stage of open-space filling with quartz-Ba-(F)-(base metals) ; and a second stage of brecciation and deposition of quartz-barite. The two mineralising events can be clearly related to two tectonic episodes of late Variscan age that involved extension along east-west trends followed by ductile transcurrent movements along northeast-southwest trends.

Jan 4, 1992

By E. A. C. Chamberlain

New techniques for the continuous sampling and analysis of mine air are expected to replace traditional methods used for the early detection of spontaneous combustion. It has been established that the rate of evolution of carbon monoxide is the earliest indicator of incipient spontaneous combustion. Two methods of continuous monitoring of this gas are available and are now in use in the UK collieries. The first is the UNOR infra-red gas analyser, which is flameproof and may be used underground; the second is a system of tube bundles, which permits air to be drawn from any critical point in a colliery and analysed on the surface. Each system has its advantages and disadvantages but both provide the colliery manager with far more information on the condition of his pit than could previously be obtained by spot sampling and laboratory analysis. This paper describes the two systems presently in use and assesses likely future developments.

May 23, 1905

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 J. Coxon, G. W. Walker

The paper describes the discovery, location and events concerning three types of heating which have occurred in recent years: a) in a district being salvaged, b) in the shaft pillar at an air-crossing, and c) in the gate side of a production district, all of which have occurred in the Beeston Seam at collieries in the deeper eastern part of the area. The paper describes the precautions, air sampling arrangements, training methods and codes of practice which have been adopted at collieries where spontaneous combustion is, or is likely to be, a hazard. The air samples taken from behind the stoppings following the sealing off of the salvaging district are examined and interpreted. The problem of effectively sealing off where more than two stoppings are required is made apparent. Other lessons have been learned as a result of these heatings and are described in the paper.

May 23, 1905

By A. B. Holland-Batt

Deposition velocities play an important role in many fields of engineering and an impressive range of measured data has accumulated in the literature. Numerous workers have addressed the problems that are associated with the prediction of deposition velocity because of its particular relevance to the design of pipelines and pumping stations. However, despite this extensive effort, the calculation of friction heads still requires reference to experimentally based graphs to determine Durand factors and there is still scope for improvement in the prediction of the deposition velocity at different solids concentrations. Equations to characterise the relationship between the Durand factor and the volume concentrations of solids in the slurry are presented. A correlation for the prediction of the deposition velocity is also developed and tested against some of the classical experimental data. The application of predicted values of deposition velocity in assessing the potential for the sanding-up of spiral separators is then described and a case study is presented.

Jan 12, 1992

By Hirsch H. H.

The paper, presented at the North of England Institute of Mining Engineers' general meeting held in Newcastle-upon-Tyne on 12th February 1916, gives a short description of the Hirsch lamp, which, though largely used in the United States of America, has not yet been adopted in Great Britain. The lamps, which consist of (1) the watchman's lamp and (2) the miner's lamp, are portable, and have been designed to provide a safe and reliable light for use by watchmen, and in mines, rescue-work, powder-works, oil-refineries, and other places where special precautions become necessary on account of the presence of explosive materials or gases. The lamps are in each in­stance operated by a storage-battery contained within a casing, and this supplies the current necessary for a miniature incandescent lamp. Each safety-lamp forms a complete unit and can be carried from place to place or held in any position. Appendices give details of battery cleaning, test results and safety reports

Dec 1, 1916

By NA NA

Hausherr UK Limited Win Order from Italian Cement company Cementerie Di Sardengnu SpA, Qualler Hall complete head gear switch in three weeks, Chief Mins Inspector 'cautiosly optimistic' on safety standards at Privatised Pits.

Jan 11, 1996

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 M J. Thomson, P T. Burgin

The economic growth of Hong Kong and adjacent territories in Southern China is, to a considerable extent, dependant on air transportation, but the present Kai Tak Airport is incapable of expansion to meet future needs. After years of study, agreement was reached to build a new airport on the island of Chek Lap Kok, some 34 km remote from Hong Kong, with an ultimate capacity of 87M passengers and 8.9 Ml of cargo per annum. Apart from the building of the airport and its associated infrastructure (including a new town), other similar massive construction works have been necessary in the form of land reclamation from the sea and existing outer lying islands. The construction of bridges, tunnels, railways and highways are also an integral part of the project. The paper provides a broad overview of the concepts of the scheme (called The Airport Core Programme) and highlights some of the major operations and equipment being used in the projects, whose cost at 1992 prices was reckoned to he Hong Kong (HR)$l63hn.

Jan 7, 1997

By R. R. Liebenberg, M. I. Brittan

The kinetics of the copper segregation process has been investigated. The experimental strategy used to isolate the rate-controlling reaction step is described. This step was found to be the chloridisation of the oxide copper minerals in the ore. The link between the rate of chloridisation and the overall rate of segregation is demonstrated experimentally. The influence on the kinetics of the various parameters in a TORCO system is examined and the implications are discussed

Dec 1, 1971