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By T R. Marrero, J W. Wilson

This paper presents costs for a coal log pipeline that can transport coal over distances from 50 km to 1500 km. The coal log pipeline (CLP) concept is a new technology in w hich coal is compacted into water impermeable circular cylinders that can be suspended in water flowing through an underground pipe. CLP includes processes to prepare the run-of-mine coal for compaction, the injection of coal logs into a pressurised water-lilled pipeline, the conveyance of the coal through a pipe including special pumping stations, and the treatment of the coal logs and water at the pipeline outlet. An 8 inch (203 mm) pipeline can transport more than 2 Ml of coal per year. CLP components have been extensively tested in bench-scale facilities where these tests have included start up/shutdown steady state flow behaviour, end of pipeline treatment of water and coal log handling, water hammer effects, abrasion of logs and pipeline, coal log manufacture, and other engineering operations. Several sites are being considered in the United States (US) for the first commercial demonstration that will probably take place in 1998. The cost calculations are based on realistic values for all the components of a CLP. including a return on investment. For pipelines of different diameter, values for coal transportation are presented in terms of $(USVtonne as a function of distance.

Jan 10, 1996

By P. Danson, D. A. White, S. Bashir

Composite ion exchange materials made of SnO2, TiO2 and MnO2 can be used to remove radioactive contaminants from nuclear waste streams. In several cases their selectivity and capacity are enhanced by mixing hydrous silica into the matrix. MnO2-SiO2 materials are especially useful for a number of reasons, such as their selection of heavy elements over caesium. Distribution constants and determinations of exchange capacities show that in many instances the properties of the composites are better than those of the oxides alone, while the presence of a chelating agent has been found to reduce the uptake of nuclides considerably. Methods are being developed for the bulk manufacture of the materials. Further work on sorption mechanisms is required to explain anomalous results, particularly the variation in exchange capacity for different elements and the ability of the oxides to sorb colloidal material in alkaline solution.

Jan 8, 1992

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 J A. Hacked

This paper explores the potential to exploit controls over the outputs of the primary blasting operation, arising from the performance consistency benefits gained in using modern bulk emulsion explosives technology. The former, allied with the latest powerful blast predictive software and measuring tools, offers the user the opportunity to apply control over both cost and performance, which has not been possible in the past.

Jan 12, 1997

By T. J. White, R. A. Farnfield

Early computerised blast monitoring equipment consisted of a digital version of the existing analogue machines with, perhaps, a few enhancements. Many additional facilities have since been developed to enable the efficient collection of high quality data. These developments are examined with reference to digital sampling, triggering systems, the storage of complete recordings and signal processing. Recent advances have been made in the use of blast monitoring systems that comprise multiple blast monitoring locations with centralised control and data collection. Software has been developed to help record blast parameters and assess environmental effects. Computer databases have many advantages over their paper counterparts. Data can be easily retrieved and processed. The scaled distances used in the prediction and control of peak particle velocities can be calculated rapidly when the data are obtained directly from a database. Since the whole vibration signal can now be recorded, signal processing can be used to provide information such as signal length, dominant frequency and response spectra.

Jan 4, 1993

By A. Hemami

In order to automate the operation of mechanical loaders it is essential to have a knowledge of the forces that act on the bucket and of the trajectory that the bucket should follow. A trajectory for the cutting edge of a bucket is derived from studies of the forces acting during the scooping phase. The proposed trajectory has a minimum energy consumption and is simple to automate. It is determined initially by setting to zero certain components of the resistive forces to the bucket motion which would otherwise result in unnecessary work and consequent energy wastage. The method for finding the appropriate trajectory is discussed on the basis of the properties of the material to be loaded and the loader size.

Jan 4, 1993

Jan 1, 1984

By K. M. Kinealy, A. R. Ramsden, D. H. French

A negative correlation exists between sphalerite composition and gold content when gold is transported as Au(HS)2(-); however, there are spatial and temporal differences within a single deposit. A previous model for the formation of volcanogenic massive-sulphide deposits within thermally intensifying and waning hydrothermal sytems in much the same way as is observed around modern sea-floor vents is supported. The results also emphasise that recognition of the mechanisms of gold transport in ancient deposits depends critically on an understanding of their mineralogy and stratigraphy

Jan 1, 1991

By S A. M Crawshaw, J A. B Fortune

Trackless battery powered haulage vehicles have been in operation in British coal mines principally for longwall face transfer and personnel transportation. Changes within the industry have resulted in the introduction of room and pillar coal mining methods and the introduction of increasingly heavier longwall roof supports This has resulted in the introduction of: • Battery powered coal haulage machines, which, without the need for trailing cables, increase productivity within room and pillar mining. • Battery powered longwall shield haulers which are capable of carry ing the heaviest shield supports currently being utilised within the British coal mining industry. The conventional machines have been adapted from an American design to meet the requirem ents of European legalisation. This has seen the- emphasis being placed upon the supplier with the European M achinery Directive being introduced, necessitating the assigning of a 'C E ' m ark to each vehicle. Battery vehicle technology has advanced to meet the demands of the ever changing market and will no doubt he further adapted to meet the requirement of the British coal mining industry.

Jan 10, 1996

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 Fearnside W. G.

Further discussion at the Midland Institute of Mining, Civil, and Mechanical Engineers' general meeting held in Leeds, March 21st, 1916, with T. Beach, vice-president, in the chair, of a paper published in Trans. Inst. Min. Engrs., 1915, vol. L, p. 573 and discussion vol. L., p. 109 and 608, comprised a brief written contribution by Faulds A.

Dec 1, 1916

By NA NA

RJB completes purchase of second lease-licence mine, Miller buys Wimpey Mining, Point of Ayr Colliery in North Wales closes, jobs created at Lithgow Minerals Processing Park, Australia.

Jan 9, 1996

By A. J. Beer, A. Wetherelt

Paper presented at the UK minerals industry conference held in Leeds, UK, 3-5 April 1995. Camborne School of Mines has developed a simple, cost-effective light-sectioning method that has been used successfully in tunnels and small stopes. Light sectioning provides an almost visual examination of the stope's excavated profile. An illuminated section of walls, roof and floor is recorded photographically. Overbreak and underbreak can then be easily quantified by reference to the designed shape. The prototype rig is described. Use of a fish-eye lens to capture a greater field of view is discussed. Calibration was achieved by comparison with images made with a conventional wide-angle lens with nominal distortion. The system is reliable under a range of operating conditions including dust, heat and humidity. It is also simple and easy to use, does not require skilled personnel and is low cost

Jun 18, 1905

By G. Mellgren, O. Mellgren

The conductivity of a solution is often used industrially to control the salt concentrations of reacting systems, normally using electrodes made of glass fitted with platinised platinum electrodes. When a standard platinum conductivity electrode was used to control the acid fed to the leaching circuit for an ilmenite flotation concentrate at Titania, Norway, a deposit of calcium sulphate (containing some calcium phosphate) covered both the platinum electrode and the external glass fitting, rendering the electrode inefficient in the course of a few minutes. A new electrode consisting of a casing, two measuring tubes and an electrode stem is described and illustrated. A significant advantage of its design is that the useful range of conductivity measurement can be adjusted by adjusting the concentration of the electrolyte in the electrode. It has been in use at Titania for about four years with an electrolyte consisting of 0-1 n HCI. It is robust and demands little maintenance.

Dec 1, 1971

By G. I. D. Roach

The leaching, with hydrochloric, sulphuric and perchloric acids, of suspensions and massive specimens of different haematite and goethite samples has been studied. Both accelerating and constant types of leaching curves have been observed. It is concluded that the grain to particle size ratio of the oxide being leached determines which type of leaching curve is obtained, particles containing a large number of individual grains producing the accelerating type of curve

Dec 1, 1971

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. E. Dunn

Paper presented at the 28th International Geological Congress held in Washington DC, July 1989 (International geochemical mapping sessions). Evidence is accumulating that reconnaissance-level biogeochemical sampling can provide valuable insight into the chemistry of the substrate. Problems such as seasonal variations in plant chemistry and the lack of a universal biogeochemical sample medium may be circumvented by adopting normalising procedures. The planet can be divided into a few climatic zones, each of which is characterised by one or two common plant genera. If it can be demonstrated that the chemical differences between certain species of a single genus are small - as is suggested by studies of boreal forests - it would seem feasible to apply biogeochemistry as a low-density geochemical mapping tool. The technique could prove particularly useful for assessing the substrate chemistry of areas of dense forest, rugged terrain and difficult access by employing airborne sampling of trees from helicopters

Jul 1, 1991

By J. R. Budden, P. A. Spencer, J. Barrett

The initially produced arsenic (III) is very toxic to the unconditioned culture but the mixed culture has the capacity to oxidise it to arsenic (V) in the presence of iron (III). It was possible to build up the resistance of the culture through progressive sub-culturing on arseno-pyrite until it could tolerate steady-state concentrations of 30 mM arsenic (III) and 200 mM arsenic (V). With some samples tested in the continuous systems the final arsenic concentrations reached 330 mM. It proved possible to use the laboratory batch data to establish the optimum operating conditions for continuous test systems with capacities of up to 32 m3. Data on the residence time, oxygen uptake rates and gold extraction from the bio-oxidised residues could then be confirmed by continuous testing without the need first to use empirical means to determine optimum conditions for continuous bio-oxidation. The data on residence time, oxygen uptake rate, solids density and neutralisation could be used to estimate the capital and operating costs of treating any given tonnage of the concentrate of interest. It was established that the arsenopyrite concentrates can be suitably bio-oxidised to cause the liberation of at least 90% of the gold content. The method is simple to operate and is flexible over a wide range of external conditions

Apr 1, 1991

By Mike O'Shea

Industrial minerals are extremely important to downstream industries and in our everyday lives. Their ontribution to the UK economy and to society as a whole is greatly underestimated. The industrial minerals sector is lacing increased pressures - environmental and competitive - both at home and abroad. These pressures are likely to increase. The Government, working in conjunction with the industry, can help the industry to meet these challenges. The role of Government is to establish a dialogue w ith the industry, to find out what its concerns are.and to ensure that these are taken into account in the draw ing up of policies that affect it. There is also a role for it in exploring, with industry, the linkages between environmental improvement and competitive advantage, and giving, w herever possible, early warning about regulatory developments. In order to maximise the effectiveness of links, industry needs to be coherently organised and represented both in the UK and in the European Union (EU).

Jan 12, 1997

By J. Gough M. D.

There are many points still obscure regarding the nature of coal-workers'- pneumokoniosis, but the interpretation of the disease has been greatly clarified in recent years. It is now known that exposure to fumes or gases or other conditions peculiar to coal-mining are not necessary factors in the production of pneumokoniosis. The same disease occurs in coal-trimmers working in the docks, and it is thus established that the inhaled dust is the primary factor. On the other hand, there is no completely satisfactory explanation of the distribution of the disease. Geological and petrological studies have not given an unequivocal explanation of the difference in incidence in different parts of the coalfield. It is an open question whether the quantity of dust inhaled is more important than its chemical composition. However, there is ample evidence from the medical side that elimination of dust and of tuberculosis from the environment of coal workers will be required to prevent pneumokoniosis. Much is being done with regard to elimination of dust, and a similar energetic action is required in regard to tuberculosis.

Jan 1, 1947