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By Ana Adé

The use of gold compounds in homogeneous catalysed organic reactions has been undervalued for many years due to the preconceived opinion that gold is an expensive and extremely chemically inert metal. However, recent reports have changed this assessment and gold salts in small amounts are known to display high catalytic activity.[1] Thus, it has been reported recently that anhydrous AuCl3 catalyses the formation of C-C and C-O bonds (usually mediated by hydrochloric and other protonic and Lewis acids).[2] Some examples include Michael type additions, selective cross cycloisomerisation/dimerisation of propargyl or allenyl ketones, benzannulation between o-alkynylbenzaldehides and alkynes or cyclisation of alkenyl furans. It is noteworthy that some of these reactions[2a] can be also catalysed by silver salts but with much lower yields. The 1,3-dipolar cycloaddition of nitrones to alkenes is a powerful synthetic method that has found numerous applications in the synthesis of a variety of carbon frameworks.[3] Several laboratories have focused on the development of Lewis acidic reagents to modulate the selectivity of the reaction.[4] Despite the extensive study performed, there are not many examples in which a metallic complex catalyses the dipolar cycloaddition. Most of these reactions require the presence of a metallic complex and nitrone in a 1:1 molar ratio. Recently, we have carried out stoichiometric reactions of the N-benzil-C(2-pyridil)nitrone, 1, with different dipolarophiles in the presence of zinc and silver compounds.[5] Apart from an increase of the reaction rate and the selective formation of one of the possible isomers, we have shown the formation of zinc and silver-nitrone complexes during the reaction, which behave as the intermediates in the cycloaddition process. As suggested by the results obtained with silver complexes, we decided to test gold derivatives (in the oxidation states of I and III). Interestingly, we have found that they can be used not only as stoichiometric reagents but they can also mediate these cycloadditions in catalytic amounts (5 to 10 mol % respect to the nitrone). Here we present the results on the 1,3-dipolar cycloaddition reaction of the N-benzil-C(2-pyridil)nitrone (2-PyBN), 1, and methylacrilate, 2, (Eq. 1) catalysed by gold(III) derivatives.

Oct 1, 2003

By J. D. Miller, D. M. Catarious, F. L. Stanley

The quality of cleaned products from coal preparation plants is often variable due to natural fluctuations in the washability characteristics of the plant feed. To combat this problem, many modern plants have installed on-line analyzers that provide feedback for the real-time control of product quality via the adjustment of circuit cutpoints. Unfortunately, optimization studies show that this approach may actually lead to increased losses of saleable coal. This paper discusses the problems associated with the real-time manipulation of circuit cutpoints and suggests alternative modes of operation that are better suited for plant optimization. A case study involving an eastern U.S. coal plant has been used to compare the economic impacts of these different approaches for plantwide control.

Jan 1, 2000

RECENTLY seven Boy Scouts were chosen from all the troops in the United States for their all-around ability, excellence in' scouting, and special ability as writers. Two of the members of this selected group were sons of In-stitute members. In the accompanying illustration, Ber-nard Queneau, son of A. L. J. Queneau, of the U. S. Steel. Corp., can be seen at the extreme left, just behind Theo-dore Roosevelt, who is shaking hands with the boy next to. Carl Zapffe (standing in the middle with his hands behind him), the son of Carl Zapffe, manager of the iron ore prop-erties of the Northern Pacific Railroad.

Jan 6, 1928

LOCAL SECTIONS (There are 60 Local Sections in the United States, 4 Foreign ) ADIRONDACK Established June 18, 1952 Paul W Allen, Chairman William Webb, Vice-Chairman Edwin Briggs, Secretary-Treasurer National Lead Company Mac Intyre Development Tahawus, New York Paul W Allen, Section Delegate R G Fleck, Alternate Section Delegate

Jan 1, 1954

By M. M. Fine

This report describes a Bureau of Mines technical feasibility study of simultaneous reduction and induration of pelletized iron ore to make a product with superior qualities as blast-furnace feed. Highly reduced, physically competent pellets can be made from magnetite and specularite concentrates that contain small additions of bentonite as binder. In batch tests, pellets were dried, surrounded with solid fuel in crucibles, and heated to the reducing temperature. Total iron content of the best products was higher than 80 percent and crushing strength of 1/2-inch metallized pellets ranged up to 600 pounds or more. Comparative tests of several commercial oxide pellets showed a wide range in crushing strengths, but most values were less than 350 pounds. Continuous tests in a rotary kiln resulted in the same degree of reduction, but the pellets had lower crushing strengths because of the limitations in the maximum operating temperature of the small kiln.

Jan 1, 1962

By David J. Kerr, Robert Mason

"From1927 to1989, the Hornemineproduced53.7 Mt of ore grading 6.1 g/t Au and 2.2% Cu from two large volcanogenic massive sulphide deposits composed primarily of pyrrhotite, pyrite and chalcopyrite. The ore bodies were hosted by a package of chlorite-sericitealtered epiclastic rhyolite tuffs which were deposited in a narrow palaeo-graben located on the flank of a major felsic volcanic centre. M ineralizingfluids percolated upward through the permeable footwall rocks and were further focussed along syn-volcanic, graben-bounding faults. Sulphides were deposited by a process of sub-seafloor replacement of the rhyolite tuffs.Gold-copper-(zinc) mineralization, including ore zones mined between 1985 and 1989 as the REMNOR ore zones, is present throughout the 900 m of felsic volcanic stratigraphy at the Horne. All the deposits were formed by syn-volcanic hydrothermal processes active during felsic volcanism. There is no evidence to indicate that any economic gold mineralization was introduced by a post-volcanic hydrothermal episode.RESUMEDe 1927 a1989, /amineHorneaproduit53.7 Mt de minerai avec une teneur de 6.1 g/t Au et 2.2% Cu provenant de deux grands amas de sulfures massifs volcanogeniques comprenant esentiellement de la pyrrhotite, de la pyrite et de /a chalcopyrite. Ces gites font partie d'une séquence de tufs rhyolitiques epiclastiques chloritises et sericitises qui ont ere déposes dans un paleo-graben étroit situe sur le flanc d' unimportant centre vo/caniquefelsique.Lesfluides mineralises ont circule de bas en haut a travers /es roches perméables sous-jacentes; ils ont été également canalises par les failles syn-volcaniques en bordure du graben. Les sulfures se sont déposes par remplacement des tufs rhyolitiques immédiatement et sous /e plancher océanique.Les zones minéralisées en or et cuivre (±zinc) - y compris celles qui ont ere exploitees au cours de l’opération Remnor (1985-1989) - se retrouvent, sans discontinuité, à travers les roches volcaniques felsiques dont l' epaisseur atteint 900 m. Ces gites se sont formes par le biais d' un processus hydrothermal qui ag issait pendant le volcanisme felsique. II n'y a aucune évidence de minéralisation aurifère d'importance économique qui soit postérieure a l' activité hydrothermale syn-volcanique."

Jan 1, 1990

By Yves Boissonnas, Marco Bettelini

"INTRODUCTION AND OBJECTIVES The operational safety of long and very long rail tunnels represents a key issue in all development stages, including design, construction, commissioning and operation. The spectrum of potential threats is very broad and challenging. These issues can only be mastered by means of a proper combination of a number of safety measures at various levels. This paper focuses on the specific safety issues and the extremely challenging conditions characterizing very long and deep tunnels. They include a significantly increased risk during operation that the incident train cannot exit the tunnel by its own means, long self-rescue and rescue distances, the presence of a number of trains, possibly mixed traffic as well as significant thermal issues. Amberg Engineering is strongly involved in the design and construction of most long and very long rail tunnels in Europe, including in particular the Gotthard Base Tunnel (GBT), Lyon-Turin Base Tunnel (LTF) and the Brenner Base Tunnel (BBT). The combined experience arising from these tunnels forms an invaluable body of expertise, which is summarized in this paper. The focus is on shared issues with practical relevant examples and project-specific solutions. Special attention will be devoted to the 57 km long Gotthard Base Tunnel, which will be operational by mid-2016 and will be the longest infrastructure tunnel worldwide. VERY LONG TUNNELS IN EUROPE Overview From the point of view of safety, tunnels in excess of about 20 km exhibit a significantly increased risk that incident trains could stop within the tunnel. This is related to the European Technical Specifications for Interoperability (TSI) on rolling stock, to be discussed in the chapter on rescue stations. This paper will specifically focus on the following longest tunnels in construction or operation, listed in Table 1."

Jan 1, 2016

By J. E. Zeilinger, John Nagy, Irving Hartman

"INTRODUCTION Experience and research have shown that an effective way to reduce structural damage from explosions is to provide adequate pressure-relief vents in the walls of equipment and buildings within which explosions might occur. In general, free or unrestricted openings represent the most efficient type of vent. However, in many manufacturing operations it is impractical to use free vents, and it becomes necessary to cover the openings with diaphragms or blow-out disks, hinged panels, or other devices, in order to give protection against weather changes, to prevent the efflux of dusts or vapors from equipment during normal operations, or for other reasons.A few data on the pressure-relieving capacities of hinged panels and a paper diaphragm were published in Bureau of Mines Report of Investigations 3924,4/ which covered the first phase of the dust-explosion venting study made by the Bureau. The present report describes recent experiments that were made to determine the relative effectiveness of an unrestricted vent and 22 types of closures, including various paper, cloth, and metal-foil diaphragms, hinged doors or panels, and several kinds of scored and unscored glass panes.The tests showed that many of the vent closures were effective in releasing the explosions rapidly during their incipient stage, so that the development of destructive pressures was prevented. Vents of this type should prove useful in safeguarding industrial equipment from severe explosion damage. The experiments disclosed that the venting capacities of the diaphragms are approximately inversely proportional to their static bursting strengths."

Jan 1, 1950

By K. K. Kershner

Nickel having a purity of more than 99.99 percent with reference to metallic impurities was electrodeposited at the Rolla Metallurgy Research Center of the Federal Bureau of Mines. The production of high-purity nickel is in keeping with the current trend in technologies for producing metals with lower and lower percentages of impurities. To understand more fully the role to be played by nickel by itself and as a component in many alloys, the element must be in a state of high purity. Procedures are outlined for purifying nickel solutions by precipitating and filtering off impurities. Details are given for using the purified solutions as electrolytes in depositing high-purity nickel. The elecneleposited nickel contained 0.0005 to 0.002 percent each of cobalt, copper, aid iron together with spectrographically detectable traces of aluminum, magnesium, and silicon. The deposits were smooth and dense; the crystalline structure was typical of an electrodeposited metal. Some preliminary experiments for purifying nickel solutions by liquid-liquid extraction are also described in this report. Tests of this type were limited since more encouraging results were obtained by other methods of purification.

Jan 1, 1961

By Bogar D. V

Often dewatering of coal tailings is inhibited by the presence of clays, making it difficult to obtain a high concentration, handleable coal tailings. The net result can be a low concentration, chocolate mousse-like tailings which poses significant sedimentation problems in a tailings dam and represents a significant environmental problem. This paper examines the coal tailings from a Hunter Valley colliery where the tailings properties are influenced significantly by the presence of montmorillonite clay. The influence of the calcium ion on the rheology and sedimentation/compression behaviour of coal tailings . containing montmorillonite already dispersed in water was investigated and revealed that very little improvement in the properties is achieved through the coagulation. The preliminary investigations also indicated that the properties of the tailings were dominated by the presence of the montmorillonite clay. Thus investigations were carried out on the clay alone in water. Investigations into the effect of dispersing samples of the clay alone in water and then coagulating with calcium compared with dispersing the clay directly into calcium ion solutions at the same calcium concentration showed huge improvements in the rheology, compressibility, sedimentation rates and sediment solids concentrations for the second dispersion method, which can be called controlled dispersion. The sediment volume fraction solids improved by more than a factor of two by controlling the dispersion of the clay. The reason for the improved properties lies in the suppression of the initial swelling of the clay, which is initially in the sodium form, thus maintaining the parallel orientation of the platelets that is present before wetting. While swelling is being suppressed, ion exchange occurs with the calcium which results in permanent swelling suppression. In the uncontrolled dispersion case where swelling is uninhibited, the clay is allowed to break up and despite the powerful coagulating nature of the calcium ion, the random orientation of the high aspect ratio clay platelets inhibits effective coagulation. Results indicate that the initial electrolyte concentration of the washwater in a coal washery is the critical factor controlling the dewaterability of clay tailings and the handleability of the dewatered product rather than the actual act of coagulating with the calcium ion. The results presented are of clear practical significance and indicate how coal tailings problems where clay dominates the rheology can be improved considerably by knowledge of the surface chemistry.

Jan 1, 1995

By F. W. Wood

A program of research was conducted by the Bureau of Mines to investigate anomalies in electrical-discharge behavior during consumable-electrode arc melting of titanium and to study the effects of these irregularities on arc-furnace explosions. A major effort was devoted to an experimental survey of arc behavior and a qualitative definition of discharge phenomena.3/ An important conclusion was that the "glow" of industrial arc-melting terminology is not a glow discharge but a skittering arc in a displaced position. The conditions that permit displaced skittering were tentatively defined. The displaced skittering arcs tended to damage melting crucibles in two ways, and details of possible mechanisms leading to crucible rupture and explosive reactions have been proposed accordingly. However, no acceptable means of preventing crucible damage was discovered.

Jan 1, 1961

By C. P. Sandberg

C. P. Sandberg, London, Eng. 1 think we should all be grateful to the Pennsylvania Railroad Company, and to their chemist, Dr. Dudley, for spending so much time and money in order to solve an important question; nor are me less indebted to the public spirit which leads them to impart tlie experience thus gained. In Europe nothing similar has hitherto been done, either by a company or by any private individual. In England the great railway companies employ their engineers in other ways, and do not keep a chemist or specialist to study rails; bat even if they did they would probably not publish the results. The chief professional engineers are so occupied with their private practice of railroad construction generally, that they cannot be expected to devote their time and energies to so special a question. The German Railway Union has, in my opinion, missed the real object of its elaborate researches by falling into the error of specifying costly, impracticable tests for rails—tests at the same time which do not infallibly expose the impurities that may be in the rails under examination. There has, therefore, been nothing done on this side of the Atlantic in the way of exhaustive study to determine the best composition for steel rails. America should consequently have full credit for the enlightened example which she has set. I wish, however, to make a few remarks on Dr. Dudley's second paper,—& paper which follows very much upan the same lines of argument as the first red three years ago, upon which I have previously touched in my pabr on the same subject read at the meeting in August last. If Dr. Dudley had discovered a new metal he could hardly, I think, have taken wore pains to prove that he was correct in his first formula for the best chemical colnposition of steel rails. But I hare seen so much done in the way of proof by experiment that I am inclined to think that almost anything can be proved by experiments and by satnples. If Dr. Dudley would only give up his formula, which would not suit any country—not even America—

Jan 1, 1881

By Gerrit V. R. Goodman, Charles D. Taylor, Edward D. Thimons, Jay F. Colinet

The importance of controlling respirable dust and methane gas levels in underground coal mining cannot be underestimated. While respirable dust can significantly affect the occupational health of underground coal miners, methane gas accumulations pose significant safety concerns for these same workers. Water sprays and machine mounted dust scrubbers offer effective control of respirable dust exposures and methane gas accumulations. Water must not only be applied carefully to avoid dust rollback to the machine operator but must create sufficient turbulence to remove dead zones that could contain high concentrations of methane gas. While the flooded-bed dust scrubber has been generally responsible for decreased worker exposures to respirable dusts, this device has proved effective in controlling methane levels at the face. This paper reviews practical applications of water sprays and dust scrubbers to control respirable dust and methane gas on continuous miner faces.

Jan 4, 2000

By R. D. Livingstone

"THE LETHBRIDGE COAL FIELD lies mainly .to the north and west of the city of Lethbridge. Mining carried on in this area for over eighty years until 1965. Before the building of a railway the coal was carried by bullock wagon to Montana for use in smelting, and for a while by river boat to Medicine Hat for railway use. The single, almost flat, worked seam is designated the ""Galt"" seam and is about 1.5 metres thick. It belongs to the Belly River formation and is under cover of 80 to 180 metres of weakly stratified sediments. A complex system of cross faults adds to the mining difficulties. Close timbering required in the entries and rooms reflected in a high timber cost and lower output per man shift. The coal is High Volatile"" C"" bituminous in rank with maximum gross calorific value of 11,200 Btu per pound and with a well defined cleavage. Roof conditions in the field range from very tender and very heavy on the south end of the field and west of the Oldman River to a more stable character to the north. Relatively speaking, the whole field would earn a rather tender rating and definitely so in relation to many U.S. fields. Floor conditions are characterized by a bentonitic type heaving in the south end of the field west of the Oldman river to a more stable situation in the north, which can tolerate shuttle car operation if kept drained. Water problems are minimal, except paralleling the Oldman River, where the seam dips below the river level. While vigilance is necessary to prevent accumulations of gas, the volume is rather limited. The seam was entered by shafts, except where small mines were located along the Oldman river banks and gained access by drifts. The coal seam was developed by driving either 3 or 4 Face entries 2 1/2 metres (8 ft) wide on 18-metre ( 60-ft) centres. Sets of dual butt entries driven at right angles to the Face entries completed development work. Normally rooms up to 8 metres wide were turned off the butt entries on up to 11 - metre centres. These were worked in groups of three to five, depending on the roof conditions, and normally advanced 60 m (200 ft). In some areas rooms had to be abandoned short of their objectives due to roof pressure, heaving floor and intermittent work."

Jan 1, 1985

By Mark Stephenson, Paul Henharen

"The objective in the mineral processing of primary ores is to liberate and effectively recover each individual economically viable diamond with minimal reduction in its potential value.There are three distinctive phases in diamond processing:Feed PreparationWhere the diamonds are liberated and waste material finer than the economically selected cut-off size is rejected. In this section we will discuss the various techniques utilised worldwide to effect feed preparation.Primary ProcessingWhere the diamonds are recovered into a high grade concentrate suitable for the more expensive and selective final recovery process. In this section we will discuss the development of primary processing from jigs and pans to the more current techniques utilised worldwide.Final RecoveryWhere there is selective rejection of waste particles until only diamonds remain. The diamonds may then be acidised prior to packing and marketing.Within these distinct phases a variety of unit processes have been utilised and this paper will discuss their relative merits, limitations and suitability in respect to the various stages of diamond project development from prospecting through to production.Basic capital and operating costs are compared for the autogenous milling route developed in the CIS and the crushing and scrubbing route utilised in the west."

Jan 1, 1994

By Frederick A. Mumpton

For more than 200 years zeolites have been familiar minerals to geologists and mining engineers as minor, but ubiquitous constituents in vugs and fractures of most basalt and traprock formations. More than 35 different species have been recognized including several, such as chabazite, erionite, mordenite, and faujasite, whose adsorption properties rival those of many synthetic molecular sieves. Igneous occurrences of this type have never been mined on a commercial scale; they are generally small and low grade, and they commonly contain as many as four zeolite minerals, along with small quantities of calcite, quartz, and other silicate minerals. Their economic beneficiation to monomineralic zeolite products has also not been achieved and, for the most part, industrial applications of zeolites have relied primarily on synthetic molecular sieves that were crystallized from hydrous aluminosilicate gels. During the middle 1950s, when Union Carbide Corp. and other groups were developing processes and markets for their fledgling synthetic zeolite businesses, natural zeolites

Jan 1, 1983

Jan 1, 1957

By J King, T Hunter, R Coleman

"The industry that supports operations and new projects is suffering a rapid decline in the currently severely curtailed capital investment environment. This is evidenced by a decline in the number of skilled teams, who are now centred in fewer locations. Other features are an aging and retiring ‘Baby Boomer’ generation, coupled with a low uptake of new graduates and the uncertainty in predicting future capital expenditure programs and requirements. Combine this with a reluctance of cash-poor operations to modernise and adapt in an environment of low metal prices, and there is a real uncertainty in how service providers will meet industry needs as they evolve.The industry that supports operations and new projects is suffering a rapid decline in the currently severely curtailed capital investment environment. This is evidenced by a decline in the number of skilled teams, who are now centred in fewer locations. Other features are an aging and retiring ‘Baby Boomer’ generation, coupled with a low uptake of new graduates and the uncertainty in predicting future capital expenditure programs and requirements. Combine this with a reluctance of cash-poor operations to modernise and adapt in an environment of low metal prices, and there is a real uncertainty in how service providers will meet industry needs as they evolve.Trends amongst service providers will be put forward as well as developing options and alternatives. These embrace a whole gamut of agile alternatives in the areas of partnering, alliances, commercial and shared risk models and mutual innovations. These will be discussed with some case studies and suggested approaches.Particular emphasis will be upon brownfield expansions and upgrades which have emerged recently as a preferred lower capital and focused way to achieve best practical outcome at lowest cost. There are a number of specific features of such brownfields projects including the requirement for very close cooperation between the execution team, operators, maintenance and suppliers and a maximum usage of site resources and ingenuity. Often, required investment hurdle rates are high, downtime allowed is minimal and site resources usage is maximised. This requires mutual trust, good planning and high health, safety, environment and community (HSEC) standards and practice. In many ways the practices and skills needed are the exact opposite of the historical ‘big greenfields’ project with which the industry has been geared for more recently.Another developing area has been with innovative commercial models and practices. These have been as a direct result of the more challenging investment criteria being adopted and the relative hunger of service providers. It has become more common to look at these commercial/costing alternatives very early in the project cycle as an essential project tool and not just as a possible option. These commercial solutions cover such alternatives as leasing and rental, deferred payments, build–own–operate–transfer (BOOT) and build–own–operate (BOO), whole-of-mine preferred spares and maintenance terms, and aggressive performance targets with real assurance penalties. Once again this requires very close mutual dealings and trust, and sufficient time allocation compared to a conventional approach.Citation:Coleman, R, King, J and Hunter, T, 2016. Upgrades, Modernisations and Expansions... Where Will the Expertise, Capability and Skills Come from in the Future?, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 69–76 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By James T. Finley

Profit, product quality, speed of operations, reliability, operator confidence, safety and environmental improvements have all been enhanced as a result of the recently completed maintenance, renovation and construction program at Crown Central Petroleum Corporation?s (Crown?s) coke calcining unit at its Pasadena, Texas refinery. (Figure 1) BACKGROUND The calcining unit was built in 1969 - 1970 and has been operated continuously. Approximately 400 to 500 TPD of high quality metallurgical grade coke is manufactured, stored, and shipped to consumers. About 1/2 of the feed stock to the calciner is manufactured in Crown's coking unit and the remainder is received, via barges, from various sources. The green coke is off loaded from the barges with a conventional grab crane that discharges into a small travelling hopper over a conveyor belt that feeds a radial stacker, which forms a stockpile on the ground. The green coke, from the coking unit at the refinery, is moved to the calcining unit with front end loaders. Reclaiming from the stockpiles is also done with front end loaders. The coke is primarily handled by covered conveyor belts. The finished product is stored in steel silos and can be shipped via railroad cars, but the majority of it is shipped out in ocean going bulk carriers. Maintenance work in the calcining unit is performed by Crown's refinery maintenance department on an as needed, on call basis.

Jan 1, 1983

The US Bureau of Mines' dictionary of mining terms defines productivity as "the efficiency with which economic resources (men, material, and machines) are employed to produce goods and services." Or, the relationship between the physical outputs and the physical inputs used to produce those outputs. As demand for mine materials dropped, mining companies and equipment manufacturers discovered that ratios between the inputs and the final products were disproportionate to the profits realized. Some companies are fighting for survival. The US, while still the most productive country in the world in absolute terms, is looking over its shoulder as other industrialized nations continue to exceed its yearly productive growth rate. According to John Belcher, Jr., of the American Productivity Center in Houston, TX, the US has seen a steady decrease in productivity growth since the mid-1960s. During the post World War II period, the US labor productivity growth rate was 3.2% annually. The slowdown began in 1965 and by the mid-1970s, the country's annual growth rate was 1%. By 1978, labor productivity growth ceased to gain at all and from 1978 to 1980 a 2% decline occurred. Solutions to the productivity decrease are increasing product prices or improving productivity. By increasing prices, though, the producer runs the risk of pricing himself out of the competitive market. To maintain an acceptable profit level, prices must increase proportionately higher than required to offset production cost increases, Belcher says. Many companies are turning to in-house productivity improvement programs as an answer to increased costs and declining profits. These programs are geared toward management commitment and employee awareness of what productivity means. Companies are finding ways of measuring productivity levels in financial reporting, budgeting, and planning. Organizational teams have been formed to coordinate activities and oversee product management, and improve productivity of materials and capital investments. This special issue of Mining Engineering examines productivity in the mining industry. First, there are articles about various, and different, factors that affect productivity in each of ME's five main readership areas - exploration, mining, processing, coal, and industrial minerals. There is also a look at mining industry productivity from the manufacturer's view. The next section of this special issue is devoted to some topics that affect all areas and sectors of mining: research, management practices, computers, maintenance, and energy management. Then follows case studies in exploration, coal, and iron and steel. These studies provide examples of practices and strategies used by companies and operations to boost productivity.

Jan 11, 1983