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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 B. B. Dhar

Slope stability at the proposed mine in Rajasthan was analysed in two dimensions using a finite difference code. The properties of the rock material were determined in the laboratory and subsequently modified to approximate those of the in situ rock mass. Geotechnical mapping was undertaken to determine the critical orientation of structural discontinuities. The results of the work indicated that an open pit 148 m in depth would be stable with overall slope angles of 60 degrees

Aug 1, 1994

By P. J. Baguley

The model has been developed on the basis of the observation that the partitioning behaviour of a particle is related to its calculated terminal velocity. It utilises a theoretical calculation of the terminal velocity of each particle class. This is then correlated with the observed partition data for a plant separator using empirically-derived functions of operating conditions which take into account effects such as bath turbulence, holes in drum lifters and feed arrangements. The model successfully decouples the effects of medium density and viscosity and is appropriate for any bath-type separator. The correlation between calculated terminal velocity and actual partitioning behaviour was established and modelled using data obtained from two Wemco drums treating Fe and Mn ores. The model can be used to predict the prevailing size-by-size partition curves and the separation (product grades/recoveries) given the washability of the feed and operating conditions. Simulations are used to show that, for the treatment of Fe ore, there is a maximum medium density beyond which product grades fall and that this maximum decreases as the proportion of magnetite in the medium increases. This is attributed to the dominant effect of viscosity at higher medium solids concentrations

Jun 18, 1905

By J. A. Finch, D. Lin

The robustness of the large-sections correction procedure, Hill's fast approximation, Barbery's correction and the PARGEN correction was examined by comparing their ability to reconstruct the true liberation distribution using sectioning data from computer-generated spheres. The results indicate that the flexibility of a correction procedure is related to the assumptions it makes about the continuity of the liberation distribution, locked-particle characteristics and ore texture. Overall, the large-sections procedure appeared to be the most generally applicable. The Hill fast approximation performed well, but this was probably because it partially incorporates the sphere model; the performance of the PARGEN and Barbery corrections varied from case to case.

Dec 1, 1995

By M. W. Robotham, H Wang

removal efficiency is analysed from a stochastic

Apr 1, 1995

Discussion of the paper presented at the North Staffordshire Institute of Mining and Mechanical Engineers' general meeting held in Stoke-on-Trent, March 27th 1916, with Mr. John Gregory, President, in the chair, included contributions by Gregory J., Cadman J., Hartley J.W., Wain E.B. and Henshaw A.M., followed by the author's reply

Dec 1, 1916

By Fearnsides W. G.

Discussion at the The Midland Institute of Mining, Civil and Mechanical Engineers' general meeting held in Doncaster on 27th May 1916, on the paper published in Trans. I.Min.E., vol.LI, 1916, p.409-448, included oral contributions by Lupton A. on the mechanisms of subsidence and water egress and by Kendall P.F. on the validity and accuracy of the contour extrapolation technique and the effect of major faults, together with the author's response

Dec 1, 1916

By J. Laskowski, J. Lekki

"The mechanism of joint action of a frother (alpha-terpineol) and a collector (ethyl xanthate) in the flotation of chalcocite has been examined. In order to study the dynamic effects of frother and collector in bubble-particle collisions, the following aspects were investigated : determination of zeta-potential. Measurements of the thickness of fluid film on the surface of chalcocite and adsorption of xanthate, as influenced by alpha-terpineol, induction time and flotation versus concentration of alpha-terpineol and ethyl xanthate.The mechanism of the adsorption-desorption phenomenon on chalcocite with regard to non-ionic molecules, e.g. a-terpineol, has been considered, and the influence of this on the stage and thickness of the intervening wet layer between a bubble and a particle, changing the probability of collision and attachment, is suggested."

Dec 1, 1971

By J. V. Wood, P. Davies, J. L. F. Kellie

A new range of wear-resistant materials is being produced by technology that has been used to develop high performance metal-matrix composites. These include steels and aluminium alloys that can be made as sheet, plate, rod or bar. The incorporation of hard, wear-resistant particles in an alloy matrix is achieved by reactive casting, spray deposition and powder metallurgical techniques. For example, large particles of TiC can be homogeneously distributed in steel during casting and the subsequent product can easily be rolled to plate. Similarly, up to 20% alumina particles and SiC can be injected, respectively, into steel and wear-resistant aluminium alloys by spray deposition. The current state of development of the process is reviewed and indications are given of the projected applications of such materials.

Jan 12, 1992

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 P wade

This is the first Presidential Address given to the Nottinghamshire Branch of The Institution following the merger of the Nottinghamshire and North Derbyshire Branch of The Institution of Mining Engineers (IMinE) and the Midland Branch of The Institution of Mining Electrical and Mining Mechanical Engineers (IMEMME). I intend to review the formation of the individual institutions as well as what has been achieved by mining related institutions over the years and finally I intend to look to our future.

Jan 11, 1996

By J. P. Ress

In 1903, seventeen years after mining of the Witwatersrand gold-bearing reefs started, the findings erf the Miners' Phthisis Commission (Transvaal) resulted in the initiation of measures with the object of controlling dust production. The substance of these measures was as follows: Removal of persons from places where they would be exposed to blasting fumes; use of water to suppress dust made in drilling and in other operations; supply and control of air to working-places; filtration of dusty air; and determination of the amount of the dust in the air. Broadly speaking, progress in dust control has followed these four lines with increasing success as the nature of the problem has become better known. Complete success has not, however, been achieved, partly because increasing mechanization of mining has intensified the problem and partly because the application of these measures is not infallible, being subject, in many cases, to human control. A brief summary of the development of these measures will lead to a description of present-day practice.

Jan 1, 1947

By D. J. Wall, T. D. Johnson, M. T. Parry, G. R. Heath

In coal-fired power stations coal is ground to a fine powder and then transported pneumatically at 25-30 m/s velocity to remote burners. Wear of the conveying pipework is a well recognised problem and traditional lining materials are Nihard and basalt. In many cases these are being replaced by alumina tiles in order to improve life and reduce the frequency of replacement. A programme of laboratory testing of candidate aluminas with AIO, contents between 85% and 99-5% has been undertaken and the results compared with field experience. This gives confidence in the erosion tests, which were designed to replicate most of the field conditions. However, it has not proved possible to draw correlations between the laboratory erosion rates and any of the materials’ bulk properties. SEM, TEM and microanalysis studies have therefore been made in order to look for microstructural aspects that could be influencing erosion rates and it has been shown that intercrystalline cohesion, the matrix phase and porosity appear to have most influence on wear performance. It is necessary to quantify these microstructural parameters if reliable erosion performance is to be obtained. This paper was read at the Institute of Ceramics Annual Convention at the University of Durham, April 1988.

Jun 12, 1905

By C G. Wall, T S. Daltaban

Three quarters of recent increases in world oil reserve estimates since 1990 have been attributed lo ‘better reservoir management' rather than to new discoveries. For the United Kingdom Continental Shelf (IJKCS), the Department of Trade and Industry (DTI) has on 2.2 bn barrels of extra oil protection through effective reservoir management of existing producing reservoirs. Past practise has been to manage petroleum exploitation on a departmental basis, with exploration assessing and ranking prospects, reservoir engineering assessing development plans and production facilities implementing plans. Any reservations necessary might involve restarting the project evaluation from scratch. Current practice is to manage an operation through asset management teams involving all disciplines. It is hoped that this approach will not only eliminate fruitless directions of effort, but the quality of work in each discipline will benefit from interaction. That is, the result of a team effort is greater than the sum of individual efforts. To date, this is most apparent with the interaction between geology, reservoir geophysics and reservoir engineering through reservoir characterization. This is the current area of greatest effort, with improved geophysical technology and computer power leading to more and more detailed and complex simulation models. The equally important interaction of reservoir engineering and production and facilities engineering applied to fields in decline has not yet achieved the prominence that it deserves. Establishing priorities in reservoir management requires the very critical evaluation of the relative value of objectives. The fact that something can be done (3-D seismic, 4-D seismic, multilateral wells, or three phase multi-layer well test analyses etc) is not a good reason for doing it. Reservoir management should he a study of value added versus cost for any activity possible or proposed. Both in the areas of reservoir data acquisition and of assessing opportunities in the period of production decline, it is likely that expert systems will need to be developed with the associated base of experience, understanding and know ledge. A n other area for the future is the elusive target of ‘enhanced ’ oil recovery, as distinct from ‘improved’ oil recovery. The most likely route forward here is the incessant scrutiny of reservoir regions and units within fields for their suitability for pilot schemes for advanced recovery techniques implemented at a favourable time. Finally, the reduction of costs, the maintenance of low. but viable rates of production and the threat of abandonment costs will increase reserves. An increase which may have appeared insignificant in the past is now more valuable.

Jan 11, 1996

By Z. Sawlowicz

Finely dispersed, primary sulphide mineralisation in the Cu-Fe sulphide zones of copper-bearing shale of the Polish part of the Permian Kupferschiefer is mainly present in the form of framboids and spherules. This type of mineralisation is especially well preserved in organic-rich shale, where it often dominates over a later diagenetic mineralisation that consists of large grains and veins. In microscopic observations special attention was paid to composite grains of copper and iron sulphides. The results suggest that the Cu-Fe and Cu sulphides precipitated in the Kupferschiefer sediment before pyritisation of the framboids had ceased and that they replaced metastable precursors of pyrite. The precipitation of copper sulphides could have been delayed owing to the formation of Cu-organic complexes.

Jan 4, 1992

By G. H. Blackwell

Sequences in open pit mining must be planned and regularly revised to incorporate changes in the variables which affect profitability. Interactive computer planning with colour graphic facilities is an effective tool for this purpose in the short and medium term. An interactive computer planning system for medium-size, low grade porphyry copper-molybdenum open pits is described. The planning system proved especially valuable during the critical stages of pushback mining when deep, inner pit ore was nearly depleted and the erratic grades of the next pushback provided ore and marginal material at a time of depressed metal prices.

Jan 8, 1993

By Gibson J.

The writer hopes to prove that the economical tram is of even greater importance than, say, the economical engine, and as no difficult and involved calculations are required, and all the governing facts are simple and well known, the former is more easily attainable than the latter. In the first section of this paper the factors that determine the size and the construction of the tram are examined; whilst in the second section the road on which it runs is dealt with

Dec 1, 1916

By P Shead, M A. Tuck

Both climate and methane control have been a prime concern in the development of the workings within the Deep Soft seam at Harworth Colliery. This paper describes the numerous methods employed over the past 15 years to effect control over these two major environmental pollutants at Harworth and describes a future method of working which will enable the output levels required to be achieved, whilst effecting the required level of both climatic and methane control. Firstly, the paper gives a broad historical overview of the steps taken since 1981, when production started in the Deep Soft seam at Harworth Colliery, to effect control over the main environmental pollutants in the seam. Secondly, the paper details the results of planning exercises undertaken to assess the various options with respect to panel layout, to achieve environmental control in future production districts. Finally, the recommended method of panel design to achieve the levels of production required is detailed.

Jan 7, 1997

By G. J. Lyman

Mayer curves are used for process calculation in coal preparation. They can also be used to smooth washability data by fitting a hyperbola of particular properties to ash and yield, but to introduce the density variable an independent relationship with ash content must be adopted. When this ash-density relationship has a realistic form at low density, the implied form of the mass distribution function is unrealistic, suggesting that Mayer curves represented by a hyperbolic functional form are unsuited to coal washery calculations for low-density separations. Their use at higher densities is also uncertain. A similar conclusion can be anticipated when Mayer curves are used for other mineral systems.

Jan 8, 1992

By R. R. Hart, R. A. Evans

This paper outlines the the methods currently being used in the West Wales Area for preventing the occurrence of any outbreak of spontaneous combustion. Stress is placed on the importance of correlating the position of a Rider Seam which is prone to spontaneous combustion. The recent introduction of the UNOR Recorder has contributed to the ability to monitor the CO content of the general body of the air during any incident. The use of modern sealants and improved methods of applying them have enabled the few instances of spontaneous combustion in South Wales to be treated promptly and efficiently. The authors describe the current spontaneous combustion problems at two collieries.

May 23, 1905