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By Gianni Bartolacci, Patrice Nadeau, Szatvanyi. Gerard, Carl Duchesne, Claude Chrétien

"Combustion is used throughout the mineral processing industry to produce steam in boilers, to dry concentrates in rotary dryers, and to apply heat treatments in pyrometallurgical furnaces. Tight combustion control is very important in latter type of furnace since the combustion conditions directly affect final ore quality. However, achieving tight combustion control is not straightforward since most of the flames encountered in industry are turbulent non-premixed flames, they are affected by several unmeasured disturbances and are often produced by burning several types of fuel simultaneously, some of them coming from other parts of the plant. A novel method is proposed in this paper to improve process and product quality control as well as to optimize the combustion conditions based on digital flame color images. Multivariate Image Analysis and Regression is to used extract the flame color characteristics from images to predict the solids discharge temperature of an industrial rotary kiln. It is shown that this method yield extremely good 10 minutes ahead forecast of the temperature and should lead to a substantial reduction in product quality variability as well as in fuel consumption.INTRODUCTIONFuel-fired furnaces are often used in the mineral processing industry for various purposes, such as for the production of steam (utility boiler), in conjunction with rotary dryers to dry mineral concentrates or in pyrometallurgical processes for induration, roasting, and so forth. These furnaces are necessary in the supply chain from the mine to the metals, but their operating costs are constantly rising due to the fluctuations in fuel prices. Moreover, these processes are now targeted by the Kyoto Protocol since they are energy intensive and they produce significant amounts of CO2 and other pollutants such CO, NOx and SO2. To achieve both a reduction in operating costs (i.e. fuel consumption) and in pollutant emissions while maintaining or improving product quality, one needs to have a very good control of the combustion process."

Jan 1, 2005

By Lawrie D. C

Finely ground beryl was decomposed by mixing with ground limestone and soda ash and heating at 900°C for 4-6 hr. The sintered mater:al was then crushed and leached by boiling under reflux with 5N sulphuric acid for up to 4 hr. The liquor containing Be, AI, Fe and other elements as sulphates, was separated from the residue which consisted mainly of silica and gypsum, either by filtration or bydecantation washing.The clarified leach liquor was first treated to remove Fe+++ by contacting with a primary amine-kerosene solution in 2 countercurrent stages. The iron free liquor was then passed to a 4-stage counter-current extraction unit where it was contacted with O·5M di- (2 ethyl hexyl) phosphoric acid (EHPA) in kerosene. Under the operating conditions, 99 per cent of the Be and 7 per cent of the Al was extracted.The Be and Al were stripped from the organic phase by sodium hydroxide solution of suitable concentration to form soluble "beryllate" and "aluminate" respectively. Most of the Be was subsequently precipitatedas Be(OH)2 by heating the alkaline solution to 90°C, the Al remaining in solution. After filtration and washing, the Be(OH)2 could be ignited directly to BeO at about 1000°C or used as a feed to further purification stages if required.A small counter-current extraction unit was operated continuously using liquor derived from the sintering and leaching stages. Dataobtained in batch laboratory tests were confirmed. A product obtained by ignition of the washed "beryllate" precipitate contained more than 99 per cent BeO.INTRODUCTIONIn 1958 an investigation was commenced into the recovery of beryllium oxide from beryl, as part of a programme to utilize mineral resources of South Australia. A survey of the literature indicated that little work had been done on direct solvent extraction of beryllium from aqueous liquors, so it was decided to apply the experience gained in this field in uranium processing to the current problem.Preliminary extraction tests on solutions of beryllium...

Jan 1, 1965

By A P. Brown

Comparison of legal permits required for mining (as opposed to prospecting or exploration) inNew Zealand, under the Mining Act 1971 and the Resource Management Act/Crown Minerals Act 1991. Mining generally receives the same treatment as any other industrial or commercial activity.

Jan 1, 1995

By Anthony Edey

It is a generally accepted and widely discussed fact that the world in general, and the United States in particular, face a shortage of energy at the present time which will become worse in the future. There is, however, no sign of a similar concensus as to the actions which would prevent or overcome this expected shortage. An immense variety of solutions has, however, been put forward, ranging from the purely political to the outer fringes of sophisticated technology. One resource which surprisingly is often only cursorily included in this discussion is the immense known petroleum reserve lying within the United States. When this subject is discussed, indeed, it is usually in the context of the improvements in production or new discovery rate that could be expected to result from possible politico-economic actions that would raise the real price obtained for domestic crude. This interest in the potential for improved domestic production is undoubtedly justified, but very little attention is normally drawn to the fact that even under the most favorable policy framework the majority of the oil that has been, or will be, discovered will remain in the ground due to the inherent limitations of production through surface wells.

Jan 1, 1979

By Frederick W. DeVries

The author was invited by "60 Minutes Australia" to provide on-site technical background on cyanide, mining, and the environment, in their investigation of the January 30, 2000, spill at the Aurul gold-recovery site in Baia Mare, Romania. Some remarks on the incident ?and its implications surround a showing of the fourteen-minute telecast. The thrust of the TV reporter was that aspects of the dam implied the owners' use of standards Jess than would have been met for installations in technologically more advanced locations (like Australia). As a result, the public-relations impact is one of embarrassment for the world mining industry.

Jan 1, 1998

By Walter S. Weeks

CONFUSION appears to exist in the discussions of fan testing because engineers do not agree on what energy should be credited to the fan in certain cases, and because certain terms that are used in the discussions seem to have double meanings. The purpose of this paper, therefore, is to discuss the useful energy that should be credited to the fan and the methods of determining this energy, and to suggest changes in nomenclature for the sake of clearness. The instruments commonly used in the measurement of fan pressures are the manometer, the static tube, and the impact tube. The static tube is a tube with small pinholes in it. When connected to one leg of the manometer and placed in the air current with the holes facing at right angles to the direction of the current, this tube causes the manometer to register the static pressure, unaffected by the impact of the air. The impact tube is a tube with an opening that faces the air current. When connected to one leg of the manometer, this tube causes the manometer to register a pressure which is the static pressure modified by the impact of the flowing' air on the end of the tube. If the static tube is connected to one leg of the manometer and the impact tube to the other leg, and both instruments are inserted close together in the air current, the static pressure is eliminated and the manometer registers the impact pressure. The efficiency of a fan is the percentage of the expended power utilized in useful work. The items to be included as useful work are a matter of convention, and as the conventions are not universal I feel that the matter is open to discussion.

Jan 1, 1929

By W. W. Adams

"The results of the fourth annual safety contest, 'mown as the National Safety Competition, contacted by the United States Bureau of Mines are herein announced. A bronze trophy, ‘Sentinels of Safety’, the gift of the Explosives Engineer magazine, has been awarded to the leading mine in each of the five groups into which the mines and quarries that participated in the contest were arranged. These five groups were: anthracite mines, bituminous coal mines, metal mines, nonmetallic-mineral mines, and carries and open-pit mines. The leading plant in each group was the mine whose employee lost the smallest number of days from accidents in proportion to the total number of man hours worked. Where two or more mines operated without a lost-time accident, the winner was adjudged to be the plant which operated the largest number of man hours during the year.The contest was based upon reports of accidents and exposure sent by the competing companies to the Bureau of Mines. Records of the five leading companies in each group were made known to a Committee of Award, consisting of the following seven members: H. Poster Bain, Secretary of the American Institute of Mining and Metallurgical Engineers; James F. Callbreath, Secretary of the American Mining Congress; W. H. Cameron, Managing Director of the National Safety Council; H. L. Gandy, Secretary of the National Coal Association; A. T. Goldbeck, Director of the Engineering Bureau of the National Crushed Stone Association; William Green, President of the American Federation of Labor; and A. J. R. Curtis, Assistant to the General Manager of the Portland Cement Association. Members of the committee voted for the winning company in each group in accordance with the rules governing the contest.. A majority vote prevailed."

May 1, 1929

By Rayner B

Five wells have been drilled in the Basker/Manta Block of VIC/P19, Gippsland Basin, resulting in sub-economic Intra-Latrobe Group oil and gas discoveries at Basker-1 and Manta-1. A total of 21 individual hydrocarbon bearing sandstones were intersected by the two wells. These reservoir sand bodies were deposited by fluvial processes in a lower coastal plain environment. The modelling of sand body orientation and geometry is a critical component in the evaluation of the two accumulations. Seismic resolution of the thin (average 2 m to 5 m) sand bodies is inadequate for mapping their orientation and distribution. Dipmeter data has been successfully applied to the problem of orienting the sand bodies using FMS images acquired during the drilling of Gummy-1 and reprocessed HDT data from Basker-1 and Manta-1. Prediction of lateral extensiveness (geometry) of individual sand bodies has also been attempted. Interpreted palaeocurrent direction from all three wells is dominantly from the NW to the SE. Reservoirs in the Manta-1/Gummy-1 area are interpreted to be predominantly channel sands, deposited by relatively low sinuosity streams. As such they would tend to have a laterally extensive, elongate geometry. Sand bodies deposited in the Basker-1 area show a predominance of laterally accreted cycles deposited by meandering streams. Channel geometry may then be limited in the downstream/upstream direction by internal permeability barriers such as clay plugs.

Jan 1, 1992

By G. M. Zhao

The gasification of lump coke with CO2 was studied in a fixed-bed reactor. The effective diffusivity of the gas was evaluated from measurements of the reactivity of the lump coke, produced by BHP Steel in New South Wales, and from kinetic parameters that were determined from the reactivity of fine grains. The grain model of effective diffusion in porous media was adopted to express the gasification rate of the lump coke and was found to fit the experimental data well. The relationship between reactivity and textural characteristics of the coke was examined

Jun 18, 1905

By M. J. Deats

INTRODUCTION To prepare the reader adequately, reference should be made to the paper 'The Pioneering of Fully Mechanized Longwall Coal Mining in South Africa' by R. T. Naude and M. J. Deats, published in the February, 1967, edition of the Journal. At the time mechanized longwalling had been proved operationally feasible with encouraging results since its inception in South Africa in mid 1965. Subsequently, further top seam panels were successfully extracted with improved productivity and with some modification to equipment. In 1968, after an overseas visit by mine officials, equipment specific to suit local conditions was acquired and lower seam trials commenced. Despite initial obstacles and difficulties the first panel was successfully mined. Modification and improvements to equipment and techniques resulted in the second lower seam panel being extracted economically during 1969-1970 and with productivity exceeding even that of top seam faces. During extraction of the second lower seam panel, gradual and complete surface subsidence occurred over the panel without affecting face operations. Rock mechanics investigations had originally indicated some uncertainty regarding adverse dolerite sill behaviour which could have caused longwall mining to be hazardous. All such doubts have now been removed. RESUMÉ AS AT FEBRUARY, 1967 Mechanized longwalling was introduced in 1965 on an experimental basis in an effort to improve productivity in the newer area of the mine and to increase the quality of the comparatively dirty run of mine feed to the washing plant. In addition advantages could be predicted in the long term by better utilizing reserves of straight coking coal and increasing the life of the mine. The top seam unit was obtained on a rental basis and by the beginning of 1967, two panels, the first having a face length of 215 m, a panel length of 345 m, seam section of 1 219 mm, and the second the same face length, a panel length of 453 m and a seam section of 1 067 mm had been successfully longwalled. At this stage a best month of 24 602 metric tons with an average of 17 364 metric tons per full working month could be reported. Results were sufficiently encouraging for the company to exercise its right to acquire the equipment as its own asset and from 1967 onward, the unit has operated on this basis. From the point of view of rock mechanics, the dolerite sill over the first two panels was known to have 'bridged', only the material below the base of the sill having truly 'goafed'. No adverse pressure effects had significantly affected face operations except for two 'bumps' towards the end of operations in each panel. Gate road maintenance presented no problem. The strong inflows of water experienced on the first face were now known to be associated with an isolated water bearing fault plane and were not experienced on the second face. TOP SEAM EXPERIENCE - MAY, 1966, TO DATE Panel 2 (February, 1966, to November, 1966) The operations in panel 2 (see Fig. 1 for location of panels) continued uneventfully until the final month in this panel. At this stage, the chocks behaved most inconsistently often lowering under the weight of the canopies alone. Roof trouble became so severe that the unit was unable to produce adequately and blasting of chocks became a daily occurrence. Finally 24 m short of the planned limit it was decided that a complete overhaul was the only solution and the extraction operations commenced. At this time, the only fatal accident associated with longwalling occurred when a Non-White inadvertently fell into the panzer conveyor transfer point at the main gate. Some gate road difficulties in this panel were overcome by bolting tapes to the roof as decking and allowing them to pass over the gate chocks and collapse into the goaf. Two cribbed roof falls were also negotiated by the gate chocks at the face ends without undue difficulties. It was decided in the light of maintenance problems encountered on this face that the best solution would be to appoint a foreman solely in charge of face maintenance crews. This step has to a large extent contributed to success achieved subsequently. Panel 2-face length 213 m panel length 456 m cutting height 1 092 mm average monthly output 16 443 t best month 19 130 t Panel 3 (December, 1966, to June, 1967) By the end of 1966 results were sufficiently encouraging for the company to exercise its right to acquire the equipment. This was negotiated and the unit has operated as such to the present date. Prior to installation in panel 3, all face equipment was thoroughly overhauled underground and the chocks boost-tested to yield-load. The costs of overhauling, including almost complete hose replacement, were much higher than anticipated. Advice had been received that complete hose replacement was common practice after +/- 18 months' operation. Shortly after commencement of operations in panel 3 the chocks again failed as they had towards the end of panel 2. At this stage, the suppliers advised that the valve gear should have been repaired during the overhaul as the needle and seat seals could no longer be relied upon. This operation was impossible to carry out on the face and would have been e1ttremely time consuming. Fortunately a new type of valve gear was then available from the suppliers, termed the capsule-type valve, and a complete change over could be made on the face. The encapsulated valve has a delrin pad sealing over a raised

By Oliver Bowles

Manufacture of lime is one of the oldest industries. Plants are distributed widely and furnish an essential raw material for numerous commodities. Use of lime in hundreds of manufacturing and chemical processes, by the building trades, and in agriculture has created a demand for large production and has necessitated exhaustive research on methods of manufacture and uses. The bibliography of publications on lime is extensive; but, for the most part, each publication has dealt with individual operations. The purpose of this paper is to present a general picture of the industry as a whole. The abundant literature has been abstracted and quoted freely, and the National Lime Association has furnished valuable data for certain sections. Publications containing more-detailed information on the various branches of the industry are referred to in the footnotes and bibliography.

Jan 1, 1952

A detailed study of the capital investment and production cost for copper electrowinning plants shows that significant savings in both can be achieved by increasing the current density. From the economic analysis it is determined that the optimum current density which will result in lowest capital investment and lowest operating cost is between 60 A/sq. ft. and 70 A/sq. ft., or at least three times as high as the Conventionally employed current density. The specific investment, expressed as $/ton-year, is found to be a function of both the current density and plant capacity and has a minimum value at the optimum current density. Empirical equations are developed for the purpose of estimating the capital investment and operating cost for plants of any production capacity operating at any current density.

Jan 1, 1972

By Alfred Wild

The Kraftile Co. plant, Fremont, Alameda County, Calif.--the largest producer of glazed, structural wall units west of the Rocky Mountains-- maintains modern processing facilities to evaluate and blend a wide variety of clays from several sources to produce quality products. The report desribes the prospecting, exploration, and test methods used to locate raw material sources and covers processing methods, cost factors, and trends. Also, the geologic and ceramic factors are considered in a general discussion of the economics, potentials, and requirements of clays as raw materials for ceramic tile manufacturing.

Jan 1, 1963

By Vasily V. Lodeischikov, Adolf F. Panchenko, Olga D. Khmelnitskaya, Vladimir E. Dementyev

Pilot plant tests of underground gold leaching from Maminskoye deposit oxide ores at a grade of 0,7 g/t Au were carried out. The underground leaching flow sheet includes Au dissolution by chlorine-containing solutions, Au adsorption from solution on active carbon, carbon concentrate ashing and calcine melting to produce high grade gold concentrate. The underground leaching system throughput was 15 m3 of solution per hour. Gold concentration in pregnant solutions was 0.12-0.13 mg/l. Gold recovery from solutions into carbon was in the range of 63-84%. It was demonstrated that the low Au recovery in the adsorption cycle was due to the presence in pregnant solutions of "active" chlorine, which destroys active carbon and causes a sharp decrease of the carbon loading capacity for gold. To improve the adsorption indices, previously dechlorinated pregnant solutions using bituminous coal or Na2S2O3, is recommended. Ion exchange process was tested as an alternative for gold extraction from dechlorinated solutions. In the testwork period, 4.4 kg of gold were produced with a chlorine consumption of 3.5 kg per 1 g of gold. During the tests a program of environmental protection measures was completed to provide the necessary safety precautions of the underground leaching works.

Jan 1, 2003

By Martin Berman

Tables of 28 positions for all the transitions for nine common analyzing crystals for first, second, and third order reflections were compiled by the Bureau of Mines to facilitate elemental X-ray fluorescence analysis on multi-element systems. The tables are based on a compatible set of wavelengths for 2,346 observed X-ray transitions of the elements lithium to americium. The results are tabulated in order of increasing wavelength as well as by increasing wavelength for each element.

Jan 1, 1969

By J. W. Dini

Introduction The mission of the Materials Fabrication Division (MFD) is to provide fabrication services and technology in support of all programs at Lawrence Livermore National Laboratory (LLNL). MFD involvement is called for when fabrication activity requires levels of expertise, technology, equipment, process development, hazardous processes, security, or scheduling that is typically not commercially available. Customers are encouraged to utilize private industry for fabrication activity requiring routine processing or for production applications. MFD is .a large diversified service organization including approximately 400 full time employees. The group provides a wide variety of processes including all common machining and fabrications operations, laser and water jet cutting, electrical discharge machining, lapping, electron beam and laser welding, vacuum brazing, heat treating, forming, electroplating and metal finishing, optical polishing and grinding, vacuum coating, vacuum engineering and a variety of plastics operations. These operations occupy more than 1,250,000 square feet of floor space. For more detail on the many fabrication related services available from MFD, see Reference 1.

Jan 1, 1992

By Alfred Wild

The Kraftile Co. plant, Fremont, Alameda County, Calif.--the largest producer of glazed, structural wall units west of the Rocky Mountains--maintains modern processing facilities to evaluate and blend a wide variety of clays from several sources to produce quality products. The report desribes the prospecting, exploration, and test methods used to locate raw material sources and covers processing methods, cost factors, and trends. Also, the geologic and ceramic factors are considered in a general discussion of the economics, potentials, and requirements of clays as raw materials for ceramic tile manufacturing.

Jan 1, 1963

By H. E. Powell

A laboratory investigation was conducted by the Bureau of Mines to study the magnetic characteristics and to measure the magnetic susceptibility of the mineral siderite. All susceptibility measurements were made by the method of Gouy on powdered samples and at room temperature. Specific susceptibilities of samples from 15 different locations, domestic and foreign, were determined. Values ranged from 66 to 103 (10-6) cgs electromagnetic units. The relation of susceptibility to mineral composition is discussed in this report. The specific susceptibilities of 76 minerals are tabulated in an appendix.

Jan 1, 1963

THE art of mine surveying has made very great progress in recent years, and is still advancing, perhaps faster than any other branch of surveying. The scope of the mine surveyor's duties has greatly increased, his instruments and methods have improved, the responsibility of his position is greater, and the end is not yet in sight.It might be supposed that such a steadily growing subject would have an adequate literature, but this is by no means the case and outsiders commonly judge mine surveyors by their text-books. Hardly any condemnation can be too strong for most of these books. The English books truckle to the antiquated and crude methods apparently still in use in England, and thereby largely aid in perpetuating them; they commonly in illustrative examples give the distances in fathoms, feet, and inches; they spend page after page discoursing on instruments that should have been forgotten long ago; they try to antagonize theory and practice by detailing such calculations as that a certain vein will contain 2,003.907 pounds of galena per square fathom, and then reduce this amazing quantity to hundredweights, quarters, and pounds. Nothing can be more unscientific, or, for that matter, less businesslike, than unwarranted assumptions of accuracy; it is, perhaps, the greatest curse of applied science. Here we have a calculation to thethousandth part of a pound, when there is probably an unavoidable error of two hundred pounds. What shall we say of a man who explains how to measure the depths of shafts to the hundredth part of an inch by means of short brass rods screwed together...

Jan 1, 1909

By Michael Rieber

Commodity transportation by barge is possible on about 25,000 miles of navigable inland waterways in the contiguous 48 states. Barge operations are used chiefly for the movement of bulk raw materials ranging from farm products to iron ore, coal, and other bulky semi-finished as well as finished products such as steel, chemicals and petroleum [3,p.7-9]. The barge industry, unlike other transportation industries, is largely unregulated. This is because all liquid bulk commodities most dry bulk commodities transported by for-hire carriers and companies engaged in private transportation of their own commodities are exempted from Interstate Commerce Commission regulations. As a result, about 15 percent of the total ton-miles of barge traffic each year is under Interstate Commerce Commission regulation [13,p.14-25].

Jan 1, 1977