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"Energy efficiency in mining and minerals processing has attracted considerable public and industry attention because of the significant quantities of energy consumption involved. In this context the question of what are worthwhile targets for energy efficiency improvements ought to be of the highest priority. It is however worth taking a step back to avoid falling in the trap of taking preconceived ideas that have been reiterated repeatedly before as gospel. The aim of this paper is to highlight areas where new or alternative approaches could potentially be the better way forward. Some may come as a surprise to conventional industry thinking. Ultimately any such solutions are attractive to practitioners not just in an environmental but also in an economic sense, and hence should be targeted through applied research and development efforts. This paper highlights key aspects of each group of opportunities and some of the individual approaches to provide an overview of the current status quo.MINING INDUSTRY POWER UTILISATION – WHERE IS THE BIGGEST BANG FOR THE BUCK?The question of where is the biggest bang for the buck when trying to determine worthwhile targets for energy efficiency improvements has not always been reported on broadly enough, typically because industry practitioners operate in specific areas of expertise and comfort zone. Looking beyond the familiar doesn’t always come easy. Any technology or methodology consideration to address energy efficiency needs to take into account the context of alternative opportunities of superior value or risks not achieving desired uptake. The following sub-chapters have been ordered by magnitude of improvement potential as best as is possible, starting with the biggest first, and the smallest last. Some may be a surprise relative to conventional mining industry thinking."

Jan 1, 2016

By H. C. Fuller, E. L. Anderson, F. S. Wartman, M. A. Cook

"This paper gives an account of the production of ductile-grade titanium powder in 100-pound batches by reduction of purified titanic chloride with magnesium, followed by grinding, leaching, and magnetic separation of the reaction product. Apparatus, technique, and methods of controlling product quality are described, and some data on operating costs are given.Although man has been aware of the existence of the element titanium for over 150 years, only recently has the metal itself been available in a form pure enough, particularly with reference to absorbed gases, to allow an estimate of its physical properties. In comparison with mild steel, the tensile strength of titanium is about the same, the resistance to atmospheric corrosion greater, and the specific gravity much less.These properties suggest the usefulness of titanium as a structural material for applications requiring resistance to atmospheric attack and a good strength-weight ratio. Although known reserves of titanium, high-grade enough to be useful at present are not sufficiently extensive to predicate that titanium might supplant iron, aluminum, and magnesium for structural purposes, the reserves are large enough to make its use as a structural material quite feasible in certain fields in which its unique properties are required.As a result of these considerations, the Bureau of Mines station at Tucson initiated an, investigation into the technology of titanium in 1938. First, a critical survey and small-scale trial of virtually all suggested methods7/ for producing the metal was made. The method devised by Kroll8/ seemed best adapted as a source of metallic titanium for, although the purity of the product was not as high as that of products from some other processes, it seemed that modifications in technique necessary for larger-scale production could be made more easily.Essentially, in applying the Kroll process, titanium tetrachloride was reduced to metallic titanium by adding the chloride slowly to molten magnesium contained in a molybdenum-lined iron reaction chamber filled with a protective atmosphere of argon. After reduction to the state of completion desired, the reduction mass and chamber were allowed to cool. Then the chamber was opened, and the reaction mass, consisting of titanium, magnesium chloride, and some unused magnesium, was removed by suitable means. Most of the magnesium chloride and metallic magnesium were removed by leaching in dilute hydrochloric acid. The leached sponge was then ground wet in a ball mill, releached in strong acid, and dried Removal of free iron by magnetic separation completed the production process.Development of the Kroll process by the Bureau was undertaken first at the station at Salt Lake City, in 1942 and the amount formed per run was increased in several steps from a few grams to pounds.9/ In addition to increasing the size of batch over that used by Kroll, the technique was simplified somewhat by the use of unlined reaction vessels."

Aug 1, 1949

By Theodore Marvin

FOLLOWING the receipt of questionnaires from many parts of the world, the Aviation Committee is completing a review of the use of aviation in mining and petroleum operations. The summary of this study should be available at the 1937 Annual Meeting in New York City, at which time several papers will be presented on specific application of aerial geologizing. From the reports received, there is little question that this air branch of mining is here to stay. Of course, the transportation of personnel arid material continues to merit attention but it is in the division of aerial geologizing that flying is finding its widest, most technical application.

Jan 1, 1937

By John D. Watson

The results of extensive field tests of a new and powerful method of hard rock excavation are presented in this report.* The method, known by the acronym REAM (Rapid Excavation and Mining), employs high velocity, smooth bore cannons to efficiently deliver energy to the rock and has been demonstrated for underground tunneling, drilling, surface benching, scaling, and secondary breakage in hard granitic rock at the Hope Valley Mine test site in California. Solid projectiles made from inexpensive materials such as concrete or steel, and weighing from 8 to 12 pounds, are launched by conventional high speed cannons and impact the rock at velocities of 5000 feet per second--an impact energy of about 4 million foot pounds (Figure 1). The energy applied at peak pressures of nearly 2 million psi over a period of tens of microseconds breaks down the rock by a complex mechanism of crushing, spalling, and initiation and propagation of fractures produced by the interaction of successive impacts and free surfaces. The main objective of the tests during 1973 was a demonstration of controllability of the underground operation of a silenced cannon. To accomplish this objective a 90-mm cannon

Jan 1, 1974

By George A. Roberts, Arthur H. Grobe

H. H. Hausner (Sylvania Electric Products Inc., Bayside, N. Y.)—I tested the 18-8 stainless steel powder described by Grobe and Roberts and the results were excellent. The powder was compacted and sintered in purified hydrogen to a very low density (approximately 20 pct and more porosity). Where the other powders show very little ductility when sintered to such a low density, the described stainless steel was surprisingly high in ductility. I would appreciate it if the authors could give us some data on a similar powder but without silicon and also data on 430 stainless steel powder. H. S. Kalish (Sylvania Electric Products lnc., Bay-side, N. Y.)—I should like to verify the excellent results obtained by Grobe and Roberts with their pre-alloyed stainless steel powder. It seems to me, however, that their data are conservative and that even better densities and higher tensile strength can be obtained with these powders by the selection of proper particle size fractions. The accompanying data were obtained by sintering compacts pressed from the powder made by Vanadium-Alloys Steel Co. to 0.8 in. in diam about % in. high in a cylindrical double action die without the use of lubricant. The compacts were sintered for 1 hr at 2370°F in hydrogen purified by passing it through a Deoxo unit (palladium catalyst) and a Lectrodryer. Even the density obtained using the as-received (—100 mesh) compacted at 40 tsi was quite high as was the hardness. This indicates that by increasing the sintering temperature slightly above 2350°F the coining and subsequent secondary sintering operation can be avoided. With the — 325 mesh fraction, however, very much higher density can be obtained and a high hardness. I have no tensile data to present, but I feel that it is not too optimistic to expect. that unusually high tensile strengths and good ductility can be obtained in this sintered material on the basis of the density and hardness data. The sintered stainless steel made by the above-described methods came out of the furnace very bright and clean. The purified hydrogen atmosphere is important in sintering stainless steel to reduce the oxide present in the powder. The result of such a sintering is good densification and good ductility of the sintered product. G. A. Roberts (authors' reply)—We are greatly indebted to Messrs. Hausner and Kalish for their discussions of our paper. Their encouraging remarks are greatly appreciated and their confirmatory data will do much to add to the value of the paper. At the present time it is impossible to provide complete data on a similar stainless steel powder without silicon, but we do know that, in general, the properties are slightly inferior. Data on such a powder and on other stainless steel types are to be published in the near future.

Jan 1, 1952

By Julian W. Feiss

Before undertaking to present to you a current analysis of copper, I would like to preface my remarks with a few observations that in themselves have a bearing upon commodity reviews in general. Having sat through a large number of such reviews since first joining the A. I. M. E. nearly forty years ago, I have no illusions about the hazards of the undertaking. If a speaker presents a statistical summary of commodity economics for the last year, most of his audience, having already read at least four commodity summaries on the identical subject, either get up and walk out or fall asleep. Should the latter happen, and were the listener to tumble from his chair and break his neck, obviously the speaker is liable. The subject matter seldom lends itself to histrionics on the part of the speaker so dangers of heart attack in the audience are not too great. Therefore the speaker, in order to retain listener interest, resorts to prophecy. Such venture was undertaken long ago by weather soothsayers, the "harouspex" of Ancient Rome, who generally cut up a sacrificial sheep and after staring at the entrails made their predictions which I understand had a batting average somewhat better than those undertaken on Wall Street based upon Dow Jones averages. Not being a licensed harouspex I cannot undertake predictions. I shall, however, fall back upon the experts.

Jan 1, 1965

By P. H. Francis

In This report, factors which currently enter into the design, manufacture, and quality assurance of explosion-proof enclosures are reviewed, with special emphasis given to the sealing concepts and sealants/cements, per se, for lenses. The physical and mechanical properties of a number of representative sealants and adhesives are measured, and found to exhibit great variance, with few discernible trends which might afford a firm base on which to establish minimum property standards. Accordingly, acceptance criteria for adhesives and sealants are suggested based on the survivability of an explosion-proof enclosure as a structure rather than upon the minimum mat real properties of its constituents. Procedures or surface preparation of adherends, and for quality assurance, also are proposed.

Jan 1, 1980

By W. P. Huleatt, R. B. McCulloch

"The Big Four zinc-deposit, directly above the north bank of the Green Mountain Reservoir on the Blue River, Summit County, Cole., was discovered in 1937 by the present owner, Walter McDaniel, who lives on the property. Mr. McDaniel, together with members of his family, have worked the mine on a small scale since its beginning and have shipped quantities of sorted high-grade ore to the International Smelting Co. at Tooele, Utah, and the Combined Metals Corp. at Bauer, Utah. More recently, parts of the nine have been operated by lessees.The property had been examined previously by the Federal Geological Survey, and the geological report was made available' to the Bureau of Mines.The Big Four mining claim was located in 1937 by Walter McDaniel and his wife Frances,- who had been prospecting in the vicinity since 1933. The discovery of the high-grade zinc deposit caused considerable excitement, as it had not been regarded as a mineralized area.Mining was begun in 1937 and carried on until 1944 by Mr. and Mrs. McDaniel with the help of a few hired miners. During 1944, parts of the mine were leased: to various parties Who produced small quantities of ore but did no development work.Shipments during 1941 .totaled 752 tons; during 1942, 387 tons; and during 1943, 510 tons. From the beginning of 1944 to April of that year, 98 tons wore produced and shipped to Utah,Since the lessees began operations, a grade of 30 to 35 percent zinc has been maintained by careful sorting. No production has been recorded for 1945.The Big Four mine is situated on Colorado State- Highway 9 between Dillon and Kremmling on the south face of Green Mountain overlooking the Green Mountain Reservoir, a Federal irrigation project on the Hue River, Green Mountain rises 1,600 feet above the general level of the valley to an altitude of 9,408 feet and the surrounding terrain, i s correspondingly mountainous and rugged."

Apr 1, 1946

One of the earliest and continuing challenges in driving sustainable development in large scale resource industry projects is around the issue of assessment û how do you measure the sustainability of a mineral operation? One of the key road blocks when confronted with this challenge is the temptation of technical folks to reach for a definition of sustainability or sustainable development. But definitions, by definition, have boundaries and limitations that serve to constrain thinking û they limit the thinking of what we can achieve with sustainability (it also acts as a barrier that constrains innovation). Rather than seeking definitions, better understanding of the core perspectives around sustainability and their application to the minerals industry provides a much more powerful platform from which to conduct assessments. But it is only when these perspectives are combined with the right framework and supporting techniques that the complex becomes doable. With the support of the perspectives and the framework, various assessment and measurement methodologies can be used; the challenge is communicating to stakeholders the sustainability character of the project in ways that are meaningful and to which people can connect. Assessment is not about finding the best or most accurate methods that fulfil strictly academic and possibly abstract requirements. The challenge is to help people understand what the impacts are, and what the value contributions will be, in a format and language that make sense in their world-view.

Jan 1, 2009

By Northcutt Ely

This volume- summarizes mining and petroleum legislation in 18 European jurisdictions. Within these jurisdictions, primary attention is given to requirements that must be met in each country for acquisition of rights to permit development of mineral resources. Coverage includes: First, identitication of the controlling laws or statutes governing minerals acquisition and reference to the administrative authority; second, analysis; of the laws governing mines and quarries and their products; third, analysis of laws applicable to natural gas, petroleum, and related materials; and fourth, mention of laws regulating offshore operations. Where pertinent, sections dealing with historical background or administration have been added in countries where minerals are subject to control of States or Provinces, those areas are considered separately from the central government.

Jan 1, 1974

By E. Fockedey

he destruction of free cyanide on a Co3O4 doped carbon felt was studied. The experiments were done with an eiectrochemical filter press cell on dilute alkaline solutions containing 250 mg/l NaCN. No chloride ions were added to the solutions. The cobalt oxide protects the felt against corrosion and has a catalytic effect on the degradation of the cyanide. This kind of electrode allows working with current density as high as 1200 Aim without any visible degradation of the felt. The most interesting results were obtained with a current density of 400 Aim' at which the cyanide concentration can be lowered to 5 mg/l with a current efficiency of more than 70 % and a specific energy consumption of about 10 kWh/ kg CN.

Jan 1, 1998

There has been a substantial increase in the use of rubber-tired front-end loaders in the mining industry in recent years. Concurrent with this increased usage, in the period of 1966 to 1970, there were at least 74 mining industry fatalities involving front-end loaders, or (on the average) in excess of one fatality per month. When the usage of front-end loaders by the construction industry and other industries, organizations, and agencies, such as the Government (i.e., Department of Defense), along with the uncounted numbers of serious, but non-fatal accidents, are included in the picture, the safety record for front-end loaders, of necessity, becomes a serious subject for study. There is an urgent need for attempts to be made to eliminate or reduce the number of safety hazards; to decrease the confusing diversity of controls designs found on present front-end loaders; to improve the maintenance and operating procedures; to formulate better personnel policies; to increase management and official awareness of the extent of the problem, in both industry and the Government; etc.; in order to decrease the number of accidents. Part of the problem may be traced to the fact that the operator of a front-end loader is frequently designated a "heavy equipment operator." This implies that he is automatically qualified to operate any model, of any manufacturer's, wheeled or tracked, front-end loader as well as many other types and classes of heavy equipment. Contrary to automotive practice, the complement of primary operating and emergency controls varies widely from model to model, as well as from manufacturer to manufacturer. Not only are certain controls present on one front-end loader model and absent on others, but there are significant differences in the modes of control operation, in the functions performed by superficially similar controls, in the location of the various controls, etc.

Jan 1, 1973

By Z. Sun, H. A. Davies

"Current understanding of the mechanisms by which glassy and crystalline thin ribbons are formed in high speed continuous casting processes is considered. A computer model of the combined heat and momentum transfer during melt spinning has been developed. The influence of roll velocity and of heat transfer coefficient (between the melt and the roll) on the temperature and velocity distributions within the melt puddle is analysed and the thickness of the extracted ribbon computed. The relative importance of heat and momentum transfer under different conditions is assessed and differences between the casting of crystalline and amorphous strip highlighted.IntroductionHigh speed continuous casting of thin metallic ribbon and strip is currently of considerable interest both to metal processers and to those studying process mechanisms. The practical interest arises both from the potential economic benefits to be gained from a shorter and more energy-efficient production route and from the ability to obtain extended and uniform thin strip having a metastable microcrystalline or amorphous structure with enhanced or unique properties. The latter arise from the rapid solidification associated with the cooling of very thin sections of melt brought into intimate thermal contact with one or two rapidly moving heat sinks.The principal processes for casting thin strip include free jet, chill-block melt-spinning (GBMS) (1), melt drag (MD) (2), planar flow casting (PFG) (3) and twin-roll casting (TRG) (4). For the first three of these, all essentially variants of melt-spinning, melt flows through a nozzle onto the circumferential surface of a rapidly rotating roll, whereas for TRG the melt passes into the nip between two contra-rotating rolls. We shall be concerned in this paper with the single-roll melt spinning processes only. For these, a puddle is established where the melt contacts the roll surface and the length of this puddle l is a function of the process conditions, notably the circumferential velocity of the roll Us and the volumetric flow rate of the melt Q. The contact time between any point on the roll surface and this puddle, or residence time eR(= l /Us) determines the thickness of ribbon t extracted from the puddle. This thickness, in turn, partly governs the cooling rate T and the amount of undercooling in the melt and thus the microstructure of the solidified ribbon."

Jan 1, 1986

By E. W. Rouse

THE year 1936 has seen rehabilitation of many plants which had been closed or severely curtailed. The Steptoe smelter of the Nevada Consolidated Copper Co. has been transformed by a rearrangement of the flow of material and utilization of mechanical handling to a maximum. The Phelps Dodge Corp. reports the construction of newer and better reverberatories at the Copper Queen smelter, and of particular interest, a single high-pressure waste-heat boiler placed directly over the uptake. There has also been a complete reconstruction of the smelter at the Laurel Hill plant of the Nichols Copper Co.

Jan 1, 1937

By J. E. Hoffman

The operation of the U .S Metals Refining Company, USMR Co. is defined below by the description of a variety of unit processes and operations the author encountered during his tenure with the operation, 1955 - 1978. The operations discussed include: sampling and sweating of radiators, processing of Indian Coin, treatment of insulated wire, baghouse and converter dust treatment, blast furnace and converter operation, the electric arc furnace, antimony control, selenium and tellurium products, electrolyte liberation with soluble anodes, and the precious metals refinery. These operations, although peripheral to the primary copper production circuit, were critical to the company's technological and economic base.

Jan 1, 2000

By J. B. Carman

This paper, describing the mining practices and methods at the mine of the Molyb¬denum Corporation of America, is one of a series of similar papers on mining methods in the various mines of the United States being prepared by the Bureau of Mines. The mine of the Molybdenum Corporation of America is in the Red River mining dis¬trict, Taos County, northern New Mexico (fig. 1), The mill and camp are in the valley of Red River, about 7 miles east of the town of Questa; the mine is 1 ¼ miles away, in Sulphur Gulch, a tributary of Red River. The mine is about 600 feet higher than the mill, at an altitude of about 8,700 feet. The climate is cold in winter, but does not interfere serious¬ly with continuous operation. The mine normally produces about 40 tons of sulphide molybde¬num ore per day, which is concentrated at the local mill and chipped to the plant of the Molybdenum Corporation at Washington, Pa.; there it is made into either ferromelybdenum or "molyte" (calcium molybdate), for use in alloys. The ore is mined from narrow, irregular veins by the cut-and-fill method. About 65 men are normally employed underground and on the surface at the mine.

Jan 1, 1931

By S Mitchell

Jetcrete Australia Pty Ltd, shotcrete contractor took the initiative in 2008 to discontinue the use of ‘road registerable’ concrete trucks for all underground works in Australia and internationally.The rationale for this decision was basic, safety. Historically these vehicles have been and still are involved in far too many accidents; this obvious trend needs to be addressed by engineering out the root cause of the problem which in this case is suitability for purpose.Road registerable concrete trucks have been widely used for the delivery of concrete in Australian mines for many years prior to and after the inception of wet shotcrete as ‘in cycle’ ground support in underground excavations around 1992. With this inception came a wide interest in the shotcrete process and an influx of new shotcrete contractors, all using road registerable concrete trucks to deliver the large volumes of Shotcrete required for these services and in turn largely increasing the use of these vehicles underground. The road registerable concrete trucks were difficult to control and each trip underground required the operators to maintain good management of the inherent risks. We virtually had no reasonable alternative for the industry and could only encourage the operators to drive with soft controls such as, reducing overall speed to a maximum of 15 km per hour when declining, regardless of the road conditions, coming to a complete halt prior to turning into any sharp corners, remaining in the same gear both inclining and declining.

Mar 21, 2011

By F. Matanzo

[Nine wire rope terminations were pull tested and fatigue tested to destruction to measure the termination efficiency and relative fatigue life. The terminations were selected on the basis off mine site visits and the specimen were assembled in a manner similar to industrial slings. To measure a termination's sensitivity to poor workmanship, both standard and modified assembly specimen were tested. Lang and Regular construction of the 6x19 and 6x37 class wire ropes were used in diameters of 13 mm (1/2 in.), 19 mm (3/4 in.), 25 mm (1 in.), 38 mm (1 1/2 in.), and 51 mm (2 in.). In static pull tests rope class, construction, and diameter interacted with the termination to influence the efficiency of the termination. In axial fatigue tests using only the 6x19 class rope, the effect of rope construction was negligible since failure was primarily dependent on the termination type. The Swaged Socket, a termination requiring a high capacity hydraulic press, gave the best overall performance in terms of efficiency and fatigue life. The short body length of the Zinc Poured Socket (RR-S-550) was attributed with the short fatigue life of this termination. The use of thermosetting resins as a replacement for zinc was demonstrated successfully for some socket designs. The fatigue life of the termination, expressed as a percentage of the fatigue life of the wire rope, was shown to be a guide for the retirement of the wire in these applications where the wiry' rope is primarily in axial loading.]

Jan 1, 1978

By WALTER S.

(New York Meeting, February, 1912,) THE earliest example of attempting to form finely-divided materials into larger masses for better adaptation to commercial use was probably the briquetting of peat and lignite-waste at Paris by the use of a clay binder. It was from this attempt that our word briquette has arisen (Fr. la brique), the formed masses being shaped similar to ordinary bricks. This term does not, however, lend itself to the many shapes of such formed material as are now being produced, as few of them aside from some of the European brown-coal products bear any resemblance to the shape of that well-known article. The term "agglomeration " has therefore been chosen as more accurately descriptive of the products now being manufactured, this term including the molding as well as the sintering. With the increasing prices of fuel and ores and the greater demand for economy in the operation of industrial plants, more ,attention has been paid in recent years to the utilization of waste products and low-grade ores and fuels. Much of the waste has been occasioned by the inability to utilize finely ,divided ores and fuels in the furnaces because they could not be kept there, or else because they clogged up the furnace-shaft so that gases could not be forced through under ordinary conditions of operation. As a result, all such fines were thrown on the dump. Again, with the exhaustion of the richer deposits of ores, concentration of lower-grade ores becomes a necessity, and most concentrates are produced in a finely-divided condition. Aside from these considerations, there is also the economy in the cost of operating the plant; a furnace running on agglomerated material will have a much greater output than one working on fines. In one instance the charge of an iron blast-furnace was changed from fine concentrates to briquettes and the output was increased four-fold; better results could have been obtained had facilities been at hand for taking care of the increased output.

May 1, 1912

By Charles Hardy, George D. Cremer

POWDER metallurgy has been established for some time as a novel method for manufacturing a great variety of articles generally specialties that could not be made conveniently by any other method. In this category are such parts as porous hearings cutting tools of sintered carbides, and electrical contacts in which the metallic constituents do not tend to alloy in the proportions employed. The industry, however, is now at a stage where it has begun to manufacture articles that can and have been made by other methods. Thus, powder metallurgy is now preferred technique for the production of numerous machine parts characterized by high strength, accuracy of configuration, and substantial lack of porosity. Manufacture of such machine parts from metal powders has no doubt been stimulated by the war, although the trend in this direction has been apparent for several years. In any case, quantity production of high-density precision pieces by ponder metallurgy is now in full suing in the United States, and such production can and should continue to expand during and after the war.

Jan 1, 1942