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By N T. Byrom

This paper is essentially in two parts. It describes how risk assessment fits into the overall framework of the activities required to control risk effectively within an occupational health and safety (OH&S) management system. It then goes on to describe the assessment of an OH&S system by the process of auditing.

Jan 7, 1996

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 A. G. Royle

Sampling formulae for in-situ material, hard rock sampling and alluvial sampling are briefly discussed

May 1, 1991

By Winmill T. F.

Paper presented at the at the Institution of Mining Engineers' general meeting held in London on 8th June 1916: In a previous paper it has been shown that the rate of absorption of oxygen by coal is neither directly proportional to the surface area of the coal exposed nor to the percentage of oxygen in the air. Further experiments are now described supporting this conclusion

Dec 1, 1916

By H. L. Shergold, O. Mellgren

The conditions of amine concentration and pH necessary for the concentration of fine haematite particles at the iso-octane-water interface have been determined. Results obtained from the related studies on the effect of pH and dodecylamine concentration on the adsorption density, electrokinetic potential, contact angle and concentration of various amine species in the system are included. A good correlation was obtained between these different variables. Maximum concentration of haematite at the oil-water interface was obtained when the haematite zeta-potential was small or equal to zero

Dec 1, 1971

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

Summary of the morning's events with a Written Contribution to Paper No. 4 and author responses

Jan 1, 1947

By T. F. Bamber

The South Nottinghamshire Area has not been greatly troubled by spontaneous combustion until the last few years, during which the Blackshale Seam has been developed and exploited. The problem was first encountered at a colliery which was heavily preoccupied with a major reconstruction scheme, and with the sudden appearance of a completely new hazard both men and management had to adapt themselves very quickly to meet the situation. The paper contributed to the Symposium by the South Nottinghamshire Area illustrates the problems by reference to actual incidents, and shows how the lessons learned from them have been applied to the shaping of future policy on the avoidance and treatment of spontaneous combustion.

May 23, 1905

By A. Ludkin

The paper presents the history of the occurrence of spontaneous combustion in the north area, together with the associated problems. These are examined and a description is given of the methods used to combat the danger, including the use of modern scientific instrumentation. Detailed reference is made to the underground trials with pack injection and sealant coatings which were carried out at Seafield Colliery following the formation of a working group to assess the performance, in the same underground conditions, of (1) sandbagging, (2) pack injection, (3) surface coating. Based on these trials, an improved and more economical method of prevention has been established. There is, however, still scope for further improvement in techniques which would take into account the problems of gradient, transport, manpower and cost.

May 23, 1905

By M. D. Gibbs, T. N. Smith, B. Verbaan

When heated in the absence of oxygen, pyrite from refractory gold concentrates decomposes endothermically to pyrrhotite, releasing sulphur. The decomposition starts at the particle surface and progresses inwards, leaving an adhering layer of porous pyrrhotite. Use of the conventional shrinking-core model implicitly assumes a negligible partial pressure of sulphur in the bed, but this pressure is in fact at least equal to the equilibrium vapour pressure of sulphur over pyrite, constituting the principal control of the rate of decomposition. Further experiments showed a decrease in reaction rate as the conversion increased. Both phenomena are attributed to the persistence of non-isothermal conditions in the fluidised bed during pyrolysis, caused by the endothermic nature of the reaction and the relatively slow rates of heat transfer to particles and vapour removal from the bed. Equipment must be developed to maximise these two parameters

Jun 19, 1905

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 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 A. M. Marabini, S. Battaglia, M. Ciriachi

A computer program has been developed that produces graphic representations of the atomic structure of any crystallographic plane of a mineral. The information provided by the program relates to a purely geometrical model of the crystal structure in which each atom is represented solely by the x, y and z coordinates of its centre. Despite its simplicity, the program can be used as a first approximation model in studies of the interaction between mineral processing reagents and the surfaces of mineral grains which are assumed to be coincident with cleavage planes.

Jan 4, 1992

"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 M. L. Schmulian

"The Windarra nickel deposits display many of the characteristics that typify Archaean volcanic peridotite-associated nickel sulphide ores of Western Australia. The Fe-Ni-Cu sulphide mineralization, which comprises dominantly disseminated sulphides, occurs at the base of a differentiated ultramafic volcanic pile grading upwards from massive meta-peridotitic flows to thin, locally spinifex-textured meta-picritic units. The entire mafic-ultramafic belt has been subjected to mid-amphibolite- facies metamorphism. The ore-bearing ultramafic is immediately underlain by dominantly sulphide-facies banded iron formation (BIF), which commonly contains nickel sulphides adjacent to its contact with mineralized ultramafic. BIF-hosted ores are formed both by physical remobilization of ultramafic-hosted sulphides and by migration of Ni and Cu into pre-existing iron sulphides.At Mt. Windarra the mineralization comprises eight steeply dipping, steeply plunging elongate oreshoots, which display a marked parallelism with major and minor fold structures in the underlying BIF. Seven of the shoots occur at or close to the base of the ultramafic pile, and are hosted by at least three overlapping flows. The zone of overlap occurs at the northern end of each flow, where picritic ultramafic, representing a dominantly liquid portion of the flow, occupies the basal contact. A gross south- north ultramafic flow direction is inferred. The eighth shoot occurs in a stratigraphically higher position within the ultramafic sequence.At South Windarra at least two overlapping mineralized flows occupy the basal contact, the ore zone having a strike extent three to four times its downdip extent. There is no obvious structural control to the mineralization."

Jan 1, 1984

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 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 N. Djordjevic

It is commonly accepted that the strength of rock measured from small samples tends to give unrealistically high estimates of the strength of larger samples, in situ blocks of rock or the rock mass in situ. The Weibull theory of the statistical strength of material provides a possible means for calculation of the strength of large rock volumes, based on the routine testing of small samples. Application of the Weibull approach to estimation of the strength of Moura coal showed an encouraging agreement with experimental results and the method was also applied to hard-rock andesitic and porphyry ore from Bajo de la Alumbrera, Argentina

Jun 21, 1905

By J. A. Saunders, E. L. Rowan

It is now widely accepted that the metal-rich waters found in the oil wells are possible present-day analogues of the mineralising solutions that formed the Mississippi Valley-type (MVT) deposits throughout mid-continental USA and elsewhere. A study characterising the trace-metal content provides additional circumstantial evidence for a genetic link between sediment-hosted mineral deposits and basin brines: Ag, Co, Ni, As and Mo, detected in the scale, are locally present in accessory minerals in MVT deposits and the levels of Ag found in the wells support the conclusion that sedimentary sources for silver should be considered in evaluating the origin of Pb-Zn-Ag deposits in sedimentary terrains

Jun 12, 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