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By AIME AIME

The first Diesel-electric locomotives for the Mesabi iron range of the Lake Superior district were put into service last summer by the Oliver Iron Mining Co., U. S. Steel subsidiary. There were ten of these locomotives, rated 1000 hp. and weighing 125 tons each. They are designed for service from 16 to 24 hours per day to haul trains of loaded ore cars from open-pit mines, 200 to 400 ft. deep, on a two to eight-mile haul to the top of the pit. The locomotives push or pull the trains over switchbacks and up heavy grades with 5 per cent maximum against the load. High tractive effort, less smoke, and ability to negotiate sharp curves were among the reasons for the selection of Diesel-electric locomotives.

Jan 1, 1941

By W. T. Abel

The difficulties associated with wet-processing fine size coal led the Bureau of Mines to investigate a dry process for removing pyrite from coal pulverized to powerplant fineness. The dry process that was investigated consists of two cleaning steps: First, centrifugal separation is used to remove a fine, pyrite-depleted portion as a product; second, the remaining coarser, pyrite-enriched portion is taken to electrostatic separation in which pyrite is concentrated and rejected. Ball milling and Hardgrove milling were used to pulverize the coal. Three coals from the Pittsburgh seam were treated by the dry-removal process. Over 55 pct of the pyrite, which amounted to 70 pct of the available pyrite, was removed in a reject of 10 to 20 pct from one of the coals. Similar treatment of the other two coals removed about 35 to 50 pct of the pyritic sulfur, which amounted to about 70 pct of the available pyritie, sulfur from these coals. Both centrifugal and electrostatic separations were more efficient when pyrite particles were as large as possible. Separation efficiency was improved by confining the particle size of the feed to a relatively narrow range and by avoiding excessive amounts (more than 10 pct) of dust in the electrostatic range. The removal efficiency was increased with the use of stage grinding.

Jan 1, 1973

By George I. Adams

PHYSICAL AND CLIMATIC DIVISIONS. PERU is divided into three regions-the coast, the sierra, or high mountainous region, and the a montana," or forest region of the Amazon basin. The Coast.-The coast is an arid region. No rain falls excepting in the extreme northern part, which borders the Gulf of Guayaquil. There is, however, a slight precipitation in the form of mist (garua), which occurs on the coast hills during the so-called winter months. The aridity of the coast is due principally to the antarctic or Humboldt ocean-current, which, being cold and having a temperature lower than that of the land, absorbs rather than produces vapors. The coast mists occur during the season when the land is relatively cold. Near the Gulf of Guayaquil the antarctic current diverges from the coast, so that in the Tumbes valley and adjacent country the conditions in the summer months are such as produce rains. In the remaining valleys of the coast, agriculture is made possible only by means of irrigation, and is accordingly very limited in extent, although rich and varied. In the northern and south-central portions of the coast, plains extend inland from the sea, while in the southern part there is a coastal plain separated from the Pacific by a range of coast hills. Between the northern and south-central plains, as well as between the south-central and southern, the foothills of the sierra descend to the seacoast. The Sierra.-The sierra embraces the high land dominated by the lofty cordilleras of the Andes. In the southern part of Peru there are two cordilleras, the western and the eastern, which enter from Chile and Bolivia respectively, and inclose between them the Titicaca Lake basin. To the north of Lake Titicaca these cordilleras unite in the knot of Vilcanota, south of Cuzco. From this knot three cordilleras, known as the western, the central, and the eastern, extend to the northward, reuniting in the

Jan 7, 1908

By A Golsby

Although much talked about, social licence to operate (SLTO) is a relatively new concept that has been deemed as one of the four biggest business risks to a mining project over the life-of-mine. There is no accepted single definition of SLTO and this author understands SLTO to be stakeholder perception of the legitimacy of a project, a company or an industry. At a specific site, and across different sites within the same organisation, SLTO ranges through different levels according to stakeholders’ degrees of acceptance in time and space. Management of SLTO is vital for the mining sector but is difficult as it is informal and intangible. Although there are no key performance indicators, there are certain indicators that enable relative measurement of the ‘level’ of the SLTO. Because of the importance of the SLTO, information management during the entire life-of-mine, from exploration to rehabilitation, becomes crucial for the continued operation of a project. This paper identifies ten basic principles for the management of information to support the SLTO.CITATION:Golsby, A, 2014. Managing information to support a social licence to operate, in Proceedings Life-of-Mine 2014 , pp 389–398 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By S. James Campbell

Ladies and Gentlemen: Never in the history of our mining industry has the emphasis on public relations been accelerated as much as it has in the last few years. Knowing of your keen interest in this subject I consider it a great privilege that your program committee has asked me here to discuss the crushed stone segment of our industry approach to this important part of our daily business lives. As you are aware, crushed stone operations are present in almost every segment of the country wherever aggregates for construction projects are required. The tonnage of crushed stone produced is second only to sand and gravel - another source of aggregates - and this together with sand and gravel amounts to over half of the tonnage of all mined products in the United States. What is unique about this industry that will be of interest to all of you in analyzing how they have approached Public Relations? The fact that it is so wide-spread is of course obvious, but perhaps a more significant nature of this segment of the mining industry that has brought it more in the limelight of public interest and on a larger scale is the location of a large part of the quarries quite close into the urban area and population centers where you have the greatest demand for aggregate products.

Jan 1, 1969

By LUDWIG VOGELSTEIN

WE are indebted to Mr. Barbour for his valuable contribution to the literature on copper statistics; it is to my knowledge the only intelligent attempt to throw light on a much misunderstood subject. If I should appear to criticize some of his findings and arguments, I do not want to leave the impression that I do not appreciate the article; I think Mr. Barbour has been painstaking, and even where one might not agree with his conclusions, he has opened our eyes and stimulated us in our search for the truth.' It might be well to define the term "secondary copper" and to make a few remarks about the origin and the reasons for the variation of the supply. Mr. Barbour has touched on these points, but not sufficiently to make them clear to those not in the business.

Jan 1, 1931

By Joseph Jensen

MANY fields have been zoned by nature with shales and intermediate waters between oil zones. Limitations thus imposed have been the basis on which the field was developed. In contrast thereto, in the Ventura Avenue Field, nature proved more generous. Always expecting to find such similar limitations, operators drilled deeper and deeper into the oil zone without finding any distinctive shale bodies other that the Gosnell shale and only one intermediate water, which became the point below which the final water shut-off of each well was made. Thus, on top of the structure, about 3300 ft. of oil-bearing zone has been penetrated below this intermediate w9ter-a distance of 4000 ft. below the Gosnell shale. At first it seemed that the greater the penetration in the zone, the better the well. The error of this assumption became evident

Jan 1, 1930

By Hu Harries

WE RECENTLY completed a study for a client, who is an applicant to export gas from the Province of Alberta, on the effects of gas export on Alberta's economy. This study was part of the client's application ?before the Conservation Board, and, no doubt, some of you are familiar with it. Submissions by other applicants in earlier hearings before the Board and before the Royal Commission on Energy, as well as claims made by parties opposing export, have also brought forward a number of other opmwns regarding possible economic effects. Ali of these studies have been on a piecemeal basis. They have dealt with particular aspects of particular applications, and only indirectly and by inference with the overall question of gas ex-port. We have prepared this paper to review the overall picture and ex-amine, as far as time permits, all sides of the question. While the paper is entitled Economic Effects of Gas Export on Alberta, we felt that the area considered should in-elude northeastern British Columbia, not only because Westcoast, the first major gas export project, is essentially a northeastern B. C. project, but because this area has historically been, from the point of view of economic, if not of political, geography, part of Alberta. In this paper, when we talk of export, we mean export from the Province or, in this case, from Alberta plus northeastern B. C. Sales to other parts of Canada have exactly the same effect on the economy of this area as l1ave sales to the United States, provided, of course, they are made on equal terms.

Jan 1, 1958

Prof. A. Ledebur, Freiberg, Saxony :* Mr. Sauveur has presented and enriched with original observations a valuable summary of the theories advanced hitherto concerning the hardening of steel; but in one particular, it seems to me, his statements call for correction. He says:

Jan 1, 1898

By J. Mikhael Erekson, Connie Campbell Brashear, Brent Meins

Christmas morning 2020, an IED in an RV was detonated along an evacuated section of downtown Nashville, Tennessee. The blast damaged over 40 buildings, including AT&T’s Main Central Office and caused internet and cell outages across 1,200 zip codes for three days including the airport and EMS services. Published investigations by the ATF and FBI were inconclusive in determining the explosive composition and size. Video captured a large fireball that may indicate a fuel-air-mixture explosion which would create lower peak pressures than high explosives, but longer pressure duration and significant impulsive loading. Blast pressures were amplified by reflections in the urban environment bordered by the 8-story AT&T building and a row of multi-story historic buildings. Some structures had little damage as they were shielded from the blast pressure by closer buildings, and seemingly far-field structures contained damage from the pressure wave after multiple reflections and propagation through porous parking garages. Damage to the reinforced concrete frame AT&T building included snapped masonry ties, cracking and spall to the closest column, and vertical displacement of the elevator, even with the brakes applied. The historic structures directly across the street from the blast partially collapsed. Initial damage included complete failures of unreinforced masonry façades, broken timber beams, and uplifted roofs. Secondary, progressive collapse took place over months as the brick walls and weakened historic mortar could not resist typical wind and environment loads. One of the close historic structures was renovated in the 1990’s and structural retrofits to comply with building codes were required. The addition of steel columns and façade tie-ins improved survivability and it remained standing with a high percentage of the front brick intact. Generally, the observed blast damage was related to a structural component’s mass and flexibility. Internal timber framing was unscathed, but many steel studs required replacement. Glazing damage was observed several blocks away and many roof membranes were punctured by falling debris. Secondary damage from broken sprinkler lines and loss of environmental control often led to more costly repairs than the initial blast pressure damage. The proliferation of bomb-making knowledge leads to hundreds of bombings each year in the US. Building risk considerations should include explosive threats along with other hazards. ASCE structural standards and design manuals have been published to address these risks and may be useful guides for building construction.

Feb 6, 2023

By E. I. Gedgagov, A. V. Tarasov, V. M. Paretsky, A. D. Besser

"Hydrometallurgical technology and equipment have been developed in the Gintsvetmet Institute (Moscow, Russia) for processing of rhenium-containing alloys waste to produce commercial- grade metal products with recovery of all valuable components. The technology is based on waste treatment with hydrofluoric acid with subsequent decomposition with nitric acid at pH = 1 to 1.5 to ensure maximum degree of rhenium conversion to the liquid phase of pulp. Some experimental lots of ammonium rhenate and ammonium molybdate were produced at a pilot plant. The following main techno-economic performance values have been achieved when processing grinding residues (balance-based tests were conducted with a lot of SP-2 alloy waste) to produce ammonium rhenate of high purity, as well as tantalum-niobium, nickel-cobalt and tungsten-molybdenum concentrates: rhenium recovery of 92.3% into a commercial product from grinding waste; production cost of 170-210 US Dollars per 1 kg of rhenium in commercial-grade ammonium perrhenate taking into account its recovery; tantalum and niobium recovery of 75- 77% into bulk concentrate; nickel and cobalt recovery of 88-89% into a mixed concentrate; tungsten and molybdenum recovery of 88% to 91% into concentrate. Introduction During the recent years the use of rhenium has been increasing at a fast pace worldwide [1]. The growing prices for this refractory metal are an essential factor encouraging collection and processing of rhenium-containing wastes. Double-component waste, such as molybdenum- rhenium or tungsten-rhenium alloys can be readily decomposed and the process of rhenium recovery does not cause, therefore, any difficulties. The main separation of metals takes place at the stage of waste digestion with acid, because molybdenum and especially tungsten remain in precipitate in the form of hydrated oxides and rhenium reports in the liquid phase, from which it can be easily extracted by solid ion-exchange or solvent extraction techniques. However, most of rhenium is contained in super-alloy waste [2]. Such waste has different contents of valuable components, such as tantalum, niobium, molybdenum, tungsten, cobalt, nickel, chromium and other metals. The basis of all such super-alloy waste is nickel. Refractory metals in the super- alloy composition are in the form of metallized target-oriented eutectics, and due to this reason hydrometallurgical decomposition of such alloys is a difficult technological task."

Jan 1, 2008

By D. K. Uko

In the stretch-bend or bending-under-tension test, a strip is rigidly clamped and restrained at each end and bent by central transverse loading using a radiused punch: The strip deflection at failure has been used as a measure of formability for high-strength low-alloy (HSLA) steels by other investigators. In this work, a detailed study is made of strains developing during stretch bending of an 80,000-lbf/ in 2 (552 MPa) yield stress steel using different punch radii. It is shown that toward the end of the process, the bending strains at both the inner and outer surfaces are tensile and suddenly increase at a rapid and approximately equal rate. The strain ratio in the failure region departs significantly from plane strain , even using a large width-to-thickness ratio of about 10. The effective fracture strains appear to be independent of bend ratio (punch radius/thickness) and significantly below the fracture s train in simple tension. Metallographic and tensile data were obtained for the subject material and, for one bend ratio, the effects on stretch-bend parameters of annealing both on this material and a. carbon steel were compared.

Jan 1, 1977

By Jesús E. Gómez

This work is a continuation of a paper presented in the 32nd DFI Annual Conference, Colorado 2007, titled ?Hollow Core Bar Micropiles - Design parameters interpreted from 260 load tests.? The first paper presented the results of the verification and proof tests performed for the retrofit of two bridges with hollow core bars that used 260 micropiles. It included an interpretation of the unit bond values in the different soils where micropiles were installed. Recently two additional bridges within the same geological environment were also retrofitted using 144 hollow core micropiles. This paper includes the interpretation of the additional data from the proof tests performed and refines recommended values for design of hollow core bar micropiles in soils similar to those encountered in these two projects. The authors believe that the data collected will significantly add to the relatively small existing database on micropile tests and may also be useful during implementation of the LRFD design methodology.

Jan 1, 2008

By William J. Douglas

This document describes the development of a conventional mining equipment data base, and an approach for conducting industrial engineering studies of arbitrary mining systems employing network techniques. Data was acquired through underground time studies. Each member of a four-man field team was assigned to a specific machine during each shift for which observations were conducted. Using digital wrist watches and networks describing the man-machine interactions, all events occurring luring the course of each shift were recorded on cassette tapes. The tapes were transcribed, coded, keypunched, and validated using computerized editing techniques. The resulting data files were processed to provide statistics relating to activity durations and event frequencies. The results were used to evaluate operator, machine, and system performance for each section which was observed. Equipment, reliability, and maintainability analyses were conducted using the industrial engineering data files in conjunction with historical information collected at the mine site.

Jan 1, 1976

By Loughnan FC

There are some thirteen laboratories in Australia in which coal petrological work is carried out on a consistent and routine basis. Applied coal petrological research is conducted by several institutions in different disciplines which can be grouped into four main categories:

Jan 1, 1989

By Hardwick F. W., O'Shea L. T.

The survey covers: coal-mine lighting prior to the invention of the safety-lamp, including candles, the flint-and-steel Spedding mill, and mirrors; the growth in knowledge of firedamp; the Society in Sunderland for Preventing Accidents in Coal Mines; Dr. Clanny's blast lamps and steam lamps; George Stephenson's tube-and-slider lamp, triple-tube lamp, punched-plate lamp and gauze Stephenson lamp; Sir Humphrey Davy's lamps; the controversy over invention priority, and other early forms of safety-lamp; 1816-1835 developments including the lamps of Upton and Roberts, M.Mueseler, John Martin, Dr. Clanny (new 4th lamp), M. Agre, John Newman, Gossart and Roberts, Francis Ellis, John Dillon and Mr. Wood (refrigerating lamp); 1836-1843 developments, notably of Mueseler lamps; 1844-1866, including lamps of the Davy, Clanny, Boty, Eloin and other types; 1867-1879, including the Gray lamp; 1880-1887, including the Marsaut lamp; and 1888-1913. Detailed reference is made to the findings of various relevant Royal Commissions and appendices include a list of the safety-lamps described in an appendix to the 1886 report and a publications list. The paper was prepared for the International congress of mining, metallurgy, applied mechanics and economic geology to have been held in London in July 1915. Discussion (p.718-724) includes a brief comment by Blackett W.C. and a longer contribution by Ashworth J., with the authors' response

Dec 1, 1916

By S. Y. Tshipeng, A. T. Kaniki

"RÉSUMÉ La lixiviation acide d’un minerai oxydé cupro-cobaltifère en milieu non réducteur et en milieu réducteur en utilisant le Fe2+ et le métabisulfite de sodium (SMBS) a été étudiée et les résultats ont été comparés. Les tests de lixiviation ont été effectués à température ambiante, dans une pulpe à 30 % solide, avec une vitesse d’agitation de 600 tr/min, un potentiel redox de 350 mV pour les tests en milieu réducteur, et un pH de 1,8. Les tests de lixiviation avec usage du SMBS comme réducteur ont donné la meilleure cinétique de lixiviation du cuivre. Pour le cobalt, c’est l’usage du Fe2+ qui a donné la meilleure cinétique de lixiviation. L’augmentation de la dose du fer dans la solution au-delà de 5 g/L a influencé négativement les rendements de lixiviation du cuivre et du cobalt. ABSTRACT Acid leaching of a copper-cobaltiferous oxide ore in a non-reducing environment and in a reducing environment using Fe2+ and sodium metabisulfite (SMBS) was studied and the results compa¬red. The leaching tests were performed at room temperature, in a 30% solids pulp, with a shaking speed of 600 rpm, a redox potential of 350 mV for the tests performed in the reducing environment, and a pH of 1.8. The leaching tests using the SMBS as a reducing agent produced the best copper leaching kinetics. As for cobalt, the best leaching kinetics was achieved using Fe2+. An increase in the amount of iron in the solution above 5 g/L negatively influenced copper and cobalt leaching yields. INTRODUCTION La République Démocratique du Congo (RDC) est un pays reconnu dans le monde pour son sous-sol qui regorge d’énormes quantités de cuivre et de cobalt (USGS, 2014; Palisade Research, 2016). La technique qui semble être la plus recommandée pour extraire à la fois le cuivre et le cobalt des minerais oxydés cupro-cobaltifères est la lixivia-tion acide en milieu réducteur. Cette technique est appliquée par la majorité des sociétés minières qui exploitent ces minerais dans l’ex-province du Katanga en RDC, à savoir: Tenke Fungurume Mining, Mutanda Mining, Kamoto Cop¬per Company, Sicomines, Gécamines, Boss Mining, Chemaf, Ruashi Mining et Somika. L’usage d’un agent réducteur est indispensable pour l’obtention d’un bon rendement de lixiviation du cobalt. En effet, plusieurs chercheurs s’accordent sur le fait que le cobalt trivalent de l’hétérogénite (CoO·2Co2O3·6H2O) est insoluble à l’action de l’acide seul; il ne devient soluble qu’après réduction en cobalt bivalent (Mwema, Mpoyo, & Kafumbila, 2002; Mulaba-Bafubiandi, Ndalamo, & Mamba, 2007; Ferron, 2008; Seo, Choi, Kim, & Tran, 2013; Stuurnam, Ndlovu, & Sibanda, 2014)."

Jan 1, 2018

By F. B. Waanders

Coal, as energy resource, possesses numerous characteristics and properties which all have an influence on its gasification behaviour. The two properties considered as critically important when evaluating a coal source for gasification is its mineral content and slagging behaviour. Research has indicated that slagging formation can be inhibited or even prevented by the addition of a fluxing agent. It is thus of great importance to understand the mineral interaction during gasification in order to select a suitable fluxing agent for the prevention of slagging and clinker formation in the gasifier. The aim of the present project is to evaluate the effect of iron as a fluxing agent and study the transformation of the mineral and added iron during gasification. A pre-determined amount of pure elemental iron (between 2wt% and 20wt%) was added to a base case coal sample in order to study the effect of the addition of iron to the coal. The transformation of the iron in conjunction with the possible iron containing minerals present in the coal was studied by means of Mössbauer analyses. Typical characterisation techniques included proximate analyses, ultimate analyses and ash composition analyses. The ash fusion temperature analyses (AFT) were used to study and predict the slagging behaviour of the iron-spiked coal samples. Even though AFT analyses only provide an average flow property, it gives a good indication of the changes that the iron addition induces on coal properties. FactSage modelling was carried out in conjunction with the Mössbauer and AFT analyses. From the proximate, ultimate and ash composition analyses it was clear that the coal used con-formed to the average characteristics measured over an extended time period. From the AFT values it was seen that an increase in the flow temperature occurred with the addition of pure elemental iron to the coal, which can be of importance for operational purposes as to raise the gasifier temperature and not to have slagging problems to occur in the gasifier. The Mössbauer data show that he-matite is the main Fe-component that forms from the pyrite originally present and from the added iron to the coal, consistent with FactSage modelling, which shows that the partial oxygen pressure determines which mineral species will form. This study opens up new possibilities when considering operational problems experienced in in-dustrial gasifiers. Successful completion of this study and a study to look at reducing conditions in the gasifier will also add to the knowledge that already exists regarding fluxing agents.

Jan 1, 2014

By Thorndycraftm R. B.

"PURPOSEThe purpose of this presentation to the Canadian Mineral Processors is to review gold heap leaching systems currently in use and discuss their applicability to Canadian ores. The author's experience with the development and operation of heap leaching spans the past four years at. Pinson, and visits to many ether heap leaches in the western United States.INTRODUCTIONBy way of introduction to the heap leaching system, I will describe in slight detail the method used at Pinson Mining in northern Nevada. This will be followed by a discussion of optional methods in use at other operations visited.The Pinson orebody is a finely disseminated, well-oxidized hydrothermal deposit. Gold particles are finer than 20- microns. The orezone hostrocks are metamorphosed and silici¬fied limestone and shale. Sulfides and carbonaceous materials are negligible.The Pinson open-pit mine has operated since June 1980. It produces 1500 tpd of C.I.P. mill feed averaging .10 oz gold per ton, and 1500 tpd of heap leach material averaging .025 oz gold per ton. Cutoff grades are 0.04 for mill feed, and 0.01 for heap leaching. Stripping ratio is 9 tons of waste and leach grade to 1 ton of mill feed.The project is located in northern Nevada at 4900 feet above sea level.,Winters are fairly severe, with freezing conditions affecting operations from early December through April. Although officially designated as ""high-mountain desert"" country, snow and/or freezing rain occur almost every week of the winter.To date, all Pinson production-scale heap leaching has treated run-90,000 tons of ore are stacked on 300 foot square clay leach pads. Cyanide leach solution is applied through ""wobbler"" sprinklers at .0025 gpm/sq ft for 60 to 90 days. The pregnant solution flows from the heap by gravity to plastic-lined ditches, into a collection sump and then through buried piping to the 2.2 million gallon pregnant solution pond."

Jan 1, 1984

Mineragraphy is a coined term to signify the field of microscopic investigation of ore minerals. The term is not euphonius and is sometimes regarded as superfluous because the subject is no more than an enlargement of the scope of petrology. In the past the practical field of petrology has been largely limited by the instruments which were designed for the study of rocks and' the microscopical properties of the transparent minerals. The addition of mineragraphy has been brought about by the use of the reflecting microscope and a totally different technique.The use of the petrological microscope, as it has been employed in the training oi geologists and mining engineers for nearly half a century, has been justified many times, not only in its application to general geological problems, but also in the more restricted field of the exploration and examination of ore deposits. It provides information of the gangue minerals and rocks associated with an ore body which is of great value in some mining fields. In cases where ore deposits occur selectively in certain favourable types of rock, the recognition and delineation of these rock types is a useful guide in prospecting. The Boulder Belt at Kalgoorlie forms one of the most striking examples in Australia where important significance is attached to different rock types, and the petrological microscope is essential to their elucidation.

Jan 1, 1932