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By Arthur P. Sanda

Thank you Clark, for that extraordinary introduction, but Paul Harvey would be disappointed if I didn't tell you ... the rest of the story. It's true that I began my career at the Boston Traveler newspaper, one of the last of the breed that started as an office boy and eventually advanced to staff reporter. However, what the biography doesn't tell you is that after that stellar rise to prominence in the Boston financial community, the afternoon Traveler was merged into the morning Boston Herald, and I was out of a job. Between the Traveler - which I closed - and the Brockton Enterprise - where I helped bring about the first labor strike in the newspaper's 100 year history - for a short period I worked double shifts at a bomb factory where we made beanbag mines for use in Vietnam. That is until the plant blew up one morning between my shifts - my last shift, as you can guess. Incidentally, my job was quality control. Before accepting my first public relations job with Boston Gas Company - and handling the media during that companies longest strike in history - I worked part time as a police officer in the small Massachusetts town of Halifax, during which time I wrecked the town's only patrol car - twice. Having contributed all I could to Boston Gas Company, I moved on to the parent company - Eastern Gas and Fuel Associates - where I was instrumental in closing down the last remaining coke plant in the Northeast in the Bridesburg section of Philadelphia - and got my first exposure to the coal industry - a visit to Eastern's last two coal mines in western Pennsylvania, Culver and Delmont - which were closed a month later. With the coal boom at its apex in the late '70s, the bosses thought it would be safe - and safer for the other subsidiary companies - for me to be given the opportunity to establish a formal public relations department at Eastern Associated Coal Corp. In my 10 years with Eastern Associated, I was able to help take the company from 17 operating mines down to 6, from 8 longwall sections down to 5, and eventually have the entire company sold to Peabody, While at the same time, bringing an end to the coal boom. It was at this point that journalism again beckoned, which coincided with COAL magazine purchasing Coal Age from McGraw Hill Publishing. In my l l years with the magazine, we've taken it from Coal Mining and Processing, to Coal Mining, to just COAL, and back to Coal Age - which is the best thing we ever did - and we've had the company sold ... twice.

Jan 1, 1999

By Admilson José Borges

Substituir todo o texto de orientação deste Template pelo conteúdo de seu trabalho. Inserir o texto com no máximo 1.500 caracteres (200 palavras), sem uso de parágrafos. Deve conter, de maneira concisa, o objetivo, a metodologia, os resultados e as conclusões do trabalhoO presente trabalho buscou identificar as principais oportunidades de melhoria na operação de carregamento de vagões no pátio de produtos na mina de Alegria em Mariana, com o propósito de aperfeiçoar, estabilizar e padronizar o processo, consequentemente aumentando-se a produtividade das pás carregadeiras CAT 990, minimizando o tempo de estadia do trem no pátio de produtos e o custo da operação. A elaboração do estudo no setor de expedição de produtos foi baseada em decisões orientadas pela ferramenta de melhoria contínua Seis Sigma e em análises de fatos e dados. Os resultados foram validados através da superação da meta estabelecida para o projeto, onde o objetivo inicial foi aumentar em 8,1% a produtividade do equipamento em relação ao valor atual, porém conseguiu-se atingir o valor de 23,5% com um ganho anual de R$1,34 milhões.

Oct 30, 2017

By Sans H

The geostatistical Discrete Gaussian (DG) model is demonstrated to be capable of providing an effective means of implementing change of support for Enterprise-style mineralisation and thus providing reliable global recoverable resource estimates. At Enterprise, sample grade distribution proves to be highly positively skewed, therefore significant deskewing of the histogram and reduction of variance occurs when going from sample to block support. The DG model was experimentally tested in'the Southern Primary Zone (SPZ) at Enterprise, where high anisotropy ratios and pronounced short range structures are observed in variograms. The experimental test was run for a change of support for which the variance reduction was. approximately 60 per cent. This reduction is similar to that predicted by Krige's Relationship ('the volume-variance relationship') for the practical situation of a change of support from 5 m vertical blasthole samples to 3 m x 8 m x 5 m selective mining unit (SMU) blocks. The DG model was found to correctly predict the grade tonnage relationships for a wide range of cut off grades. The experimental test indicated that, given a representative histogram and variogram, the DG change of support provides a computationally efficient and practical means of reliably assessing global mineable resources at the early stages of a mining project. Further, it allows a range of selectivity strategies to be meaningfully and comparatively considered prior to mining.

Jan 1, 1995

By J. E. Gill

Introduction During the past summer, detailed geological mapping was extended to cover the entire group of 31 claims owned by Waite-Ackerman-Montgomery Mines, Ltd., and considerable new information was revealed by development and exploratory work underground. These new facts provide a more complete view of the lithology and structure of the area than has heretofore been available. They also necessitate revision of certain interpretations presented last year by Peale (l), and have served to straighten out some of the problems suggested by Porritt (2). The purpose of this paper is to outline in a broad way the relations as now understood and to discuss in detail certain points which should be of interest to members of the Institute. Maps and records by the mine staff have been freely used in arriving at the interpretation presented in the following pages. The writers are especially indebted to Mr. R. V. Porritt, the mine manager, with whom many of the problems touched upon were discussed on the ground and whose intimate knowledge of the geology of the underground workings aided greatly in testing various hypotheses. The writers have profited greatly, also, from close association with Dr. W. F. James during the course of the work. Permission to publish the included data has very kindly been given .by the management.

Jan 1, 1932

By Stewart R. Wallace

Members of the Society, it is a very great honor for me to be here today and to have the opportunity of telling you about some things that have been accumulating in the back of my mind for some time. Before attempting to do so, I should acknowledge my debt to the many people who are responsible for my presence here this afternoon. To do this properly, however, would consume much of my allotted time and I will therefore mention only two men, both of whom were directly involved in the discovery of the Henderson ore body. The first of these was Robert Henderson, now dead, who at the time the work was going on was vice president of Western Operations of the Climax Molybdenum Co. Truly, he provided the environment that permitted the exploration program to function effectively, and the deposit appropriately bears his name. The second man I meant to mention was resident geologist at Urad at the time of the Henderson discovery. I think I should explain right here that the Urad ore body and the Henderson ore body, although entirely separate, are closely related deposits, and that both are located at Red Mountain in Clear Creek County, Colo.

Jan 6, 1975

By W. H. Young

MOST OF THE key items in the bituminous-coal and Lignite industry declined in 1954 compared with 1953. Production, consumption, exports, average value per ton, men working, and days worked all declined; however, in the field of mechanization, the percentages mechanically loaded, mechanically cleaned, mined by auger, and mined by stripping all increased, as did production per men per day. Production.-The output of soft coal in 1954-391.7 million tons- was 14 percent less than the 457.3 million tons produced in 1953. The lower production in 1954 was due largely to a sharp reduction in consumption in the United States and to a drop in exports.

Jan 1, 1958

By Gordon E. Agar, David M. Hopstock

This paper describes the procedures and results of a series of experiments conducted to determine the depressing effect of sodium, calcium and magnesium ions on the amine flotation of quartz. It also presents an analysis of the experimental results by the electrical double layer theory. The flotation of quartz with primary amines has been practiced on a large scale in the phosphate industry for many years. Some glass sand —and recently iron ore — has also been treated by this flotation technique. These applications have been highly successful and demonstrate that a complete mastery of all the details of an operation is not needed to achieve an economic success. There are times, though, when it becomes important to recognize, both qualitatively and quantitatively, the effects of some previously ignored variables. The effects of cations on the amine flotation process, particularly those ions that contribute to water hardness and abound in sea water, are a case in point. In conjunction with the development of a cationic flotation reagent for separating quartz from apatite, it became necessary to quantify the influence of calcium and magnesium on the separation. In order to strengthen and broaden current understanding of the flotation process, the results were interpreted by means of the electrical double layer theory. THEORETICAL BACKGROUND Assume that, given the same equipment, procedure, and time, the recovery of quartz by amine flotation is a function of only the adsorption density of aminium ions in the Stern layer, i.e., that for any given adsorption density there exists only one recovery percentage. By the Stern-Grahame treatment of the electrical double layer,'-' for any ionic species in a solution in equilibrium with quartz,

Jan 1, 1969

By Karsten Zimmermann, Peter Cain

"To receive regulatory approval for a new coal mining operation in North America, extensive investigations of feasibility and potential environmental impacts, including ground deformations, are required. Figure 1 shows pictures from mine sites and an example mine map with the planned panel layout for one seam of the multi-seam longwall operation considered.The cumulative mined coal thickness of 22 meters in some areas of the operation requires a comprehensive forecast of expected ground movements and subsidence impacts (e.g., subsidence, slope, displacement, curvature and strain). In the frame of the impact study, the prediction of these impact factors was conducted by DMT using the computer program SPS 4D, based on the Ruhrkohle modeling method by Ehrhardt and Sauer (1961).This paper briefly presents the modeling method and explains the benefits and possibilities for its international application. Information gathered from literature studies on subsidence in North America were incorporated into the initial model parameterization. The article shows the ways in which the observed influences of mountainous topography on surface displacements and deformations can be considered by an extension of the subsidence prediction model and integration of DEM information.SUBSIDENCE MODELFor the calculation of mining-induced subsidence and deformation, DMT has developed subsidence prediction software SPS 4D, which is built according to the stochastic prediction model by (Ehrhardt and Sauer, 1961). The model is based on the subsidence theory by (Knothe, 1953) with a specific parametrization of the stochastic influence function and includes enhancements for dynamic subsidence calculations after (Sroka, 1978). In Europe, mainly in Germany and Poland, the model is approved by the authorities as a standard model for subsidence prediction in mining areas. However, extensive research within R&D activities has shown the possibility to predict mining-induced subsidence considering the specific mining conditions in North America (Zimmermann and Fritschen, 2007)."

Jan 1, 2016

[†AARONSON, ALFRED E., Vice-Pres., Mid-Co. Petroleum Co., Mid-Co. Bldg., Tulsa Okla. '18 ABADIE, EMILE R., Min. Engr Box 927, Porterville, Cal. '76 ¦ABADILLA, QUIRICO A. Student, Colorado School Of Mines, Golden, Colo. '20 ABBOTT, CLARENCE E., Gen'l Supt. Iron Mines Div., Tenn. Coal, Iron & R. I. Co., 1405 Minnesota Ave., Bessemer, Ala. '04] [ ]

Jan 1, 1925

By Staff

The uninitiated, first-time visitor to the Copper Cliff Smelter of The International Nickel Company frequently finds it strange that the world's largest nickel producing works is located at a site seemingly named in honour of another metal. Industry-wise persons who know The International Nickel Company through its nickel producing, fabricating and sales organizations can be just as surprised to learn that Inco's annual copper production from the Sudbury area mines nearly equals that of nickel. But when the history of the mines and smelters of the Sudbury district is reviewed it is impossible to separate the stories of copper and nickel. In fact, going even further back in time (I), it was due to the similarity in appearance of the nickel bearing mineral niccolite (NiAs) to that of copper ore that led nickel to be tagged with the rather uncomplimentary name of kupfer-nickel or Old Nick's Copper - The Devil's Copper. This was in approximately 1650 and it would take another hundred years, until 1751, before Axel Cronstedt of Sweden obtained nickel in its pure form and permitted it to take its own place in the family of metals. One hundred more years passed before mining came to northern Ontario and approximately one hundred thirty before the beginnings of development of the Sudbury Basin.

Jan 1, 1976

By R. V. Higgins, H. C. Miller

"INTRODUCTION The development of methods for determining the total quantity of crude oil that a given pool could be expected to produce in the future and the well-spacing and drilling programs most likely to result in the recovery of the maximum quantity of oil at the minimum cost became problems of acute concern to American oil producers and petroleum engineers during the second decade of the twentieth century, The United States faced what seemed at that time to be a serious shortage of petroleum, and it appeared that the constantly increasing demand for petroleum and its products could not be adequately supplied. Undrilled prospective acreage, which until then had been plentiful, seemed to be getting scarcer, competition was increasing, the margin of profit to the producer was shrinking, and the need for developing constructive policies of conservation appeared paramount. As a result of physical and economic changes then taking place within the petroleum industry prompted by the seemingly uncertain future, accurate knowledge pertaining to the probable future production of oil wells and of oil lands especially was needed and greatly desired. Furthermore, the need for obtaining the maximum quantity of oil from known fields caused technical information - which up to that time had not been deemed essential to the successful and profitable operation of oil lands - to be sought eagerly. The need for technical information, such as methods for determining future reserves of oil and the rate at which the oil could be obtained under a specific program of drilling, was emphasized further with the passage of the Revenue Act of 1918, and oil producers with enough income to place them in the taxable class were compelled, for the first time, to report their taxable income 4/ to the Treasury Department."

Nov 1, 1939

By A. J. Leighton

An improved mathematical model with the attendant computer program to calculate multiphase fluid flow in petroleum reservoirs is presented. The model is used to simulate the behavior when a fluid is used to displace hydro-carbon fluids in a reservoir. The method is an expansion of a previously published method, in Bureau of Mines RI 7011, but handles constant injection rate as an alternative to constant pressure. Program documentation is provided along with thorough explanations of the added program features. Using the program, the petroleum engineer can calculate oil recoveries for different flood patterns and operating conditions and select the conditions most likely to optimize recovery. Experience with the previous model demonstrated the need for the improvements in order to simulate reservoir behavior more accurately. The improved method will result in improved oil recovery. In this paper, the significant improvements are described in detail so that anyone interested can put the program to use.

Jan 1, 1975

By J. Gordon Parr, D. H. Polonis

The formation and subsequent decomposition of metastable phases in Ti-Ni alloys containing up to 11 pet (atomic) Ni have been studied. The decomposition of a completely retained ß phase and of a completely transformed 8 phase in a 6 pet alloy has been followed by X-ray diffraction and metallographic methods and by hardness determinations made during the process. The possible mechanisms of the reactions are discussed. PREVIOUS investigations of the Ti-Ni system have usually been limited to phase diagram studies; but little attention has been given to metastable phases and tempering processes. These are important, however, since equilibrium conditions are rarely achieved—nor, perhaps, are they desired—in practice. Up to the present time the available transformation data for titanium alloys appear to be restricted to isothermal transformation curves for selected binary and ternary systems. No quantitative studies have been made of the mechanism by which equilibrium is approached. Several independent investigations have been carried out to determine the Ti-Ni phase diagram. Early work by Wallbaum' and later by Long et al.' produced tentative phase diagrams which were not representative of true binary conditions, since the alloys were contaminated with oxygen and nitrogen. The most recent diagram (Fig. 1) is due to Margolin et al.," and a slight modification of the a + ß/ß boundary (shown dotted) has been proposed by McQuillan.' The structure of the phase Ti,Ni was shown by Duwez and Taylor" to be face-centered-cubic, with 96 atoms per structure cell. The formation of a martensitic ß phase (close-packed-hexagonal) in Ti-Ni alloys has generally been observed when specimens of low nickel content are rapidly cooled from the 0 (body-centered-cubic) range. Margolin et al. reported an increasing tendency for P to be retained in lump specimens as the nickel content increases. McQuillan' has studied the effect on the microstructure of delay time in quenching, and has reported the formation of pro- eutectoid a precipitate in a quenched hypoeutectoid alloy. In a previous study of Ti-Fe alloys," experiments were made on powder specimens produced by filing alloy ingots. Techniques were devised for the preparation and heat treatment of alloys, and X-ray diffraction methods were used both for structure determinations and phase ratio estimations. A similar approach has been made in this study of Ti-Ni alloys. Experimental Methods Ten alloys ranging from 0.25 pet to 18 pet Ni* * All compositions are in atomic percentages unless otherwise stated. were prepared from iodide titanium bar stock (hardness Rf 72) and Johnson-Matthey spectrographic standard nickel by levitation melting.' As a check

Jan 1, 1957

By David Schlain

The galvanic corrosion properties of titanium and zirconium were investigated by the Bureau of Mines. The dissimilar metals involved in these experiments included magnesium, magnesium alloy FS1, aluminum alloys, zinc, steel, tin, lead, copper, Monel, nickel, and several stainless steels. Couples were immersed in synthetic ocean water, tap water, 5-percent ammonium sulfate solution, 5-1/2-percent sodium chloride solution, sodium hydroxide solution, 0.1 N hydrochloric acid, and various concentrations of sulfuric acid.

Jan 1, 1956

By M. D. Ballain, V. C. Storhok, B. Pesic, J. C. Sever

Northwest Alloys, a wholly owned subsidiary of Alcoa, produces magnesium from dolomite by reduction with ferrosilicon and aluminum. This process produces alkaline by-products in quantities that allow their consideration for use as commercial by-products. Two such products are dicalcium silicate slag, Di-Cal, and magnesium oxide condensate, MgO. The alkaline properties of these materials offer acid neutralizing capability comparable to the traditionally used lime, therefore, warranting a study for their use in applications where the neutralization of acidic waters or process solutions is required, such as treatment of mine waters. In this ongoing study, three mine waters (Bunker HillMine, Berkeley Pit, and Blackbird Mine) were selected for treatment with Di-Cal and MgO. Lime was used as the background control. The solid precipitates were subsequently contacted with pure water at four different pH conditions for stability testing of prepared metal precipitates (expanded TCLP). It was found that neutralization with Di-Cal results in precipitates which are of equivalent to superior stability than those from lime treatment.

Jan 1, 1999

By Alejandro Freyre Belliki

El presente trabajo describe las causas del abandono de mineral, las razones de su recuperación de las antiguas explotaciones, así como el estudio de las técnicas más adecuadas para realizar dicha operación. Entre las causas del abandono de mineral tenemos: la variación de precios de metales, calidad y complejidad del mineral, seguridad, derrumbes y el método de explotación. También se mencionan los casos de recuperación de materiales útiles como rellenos antiguos, mineral "in situ", derrumbes y minerales dejados en mantos. Finalmente, se evalúa la posibilidad de hallar reservas recuperables y por ende, examinar la factibilidad de su recuperación. Asi también, las zonas recuperables son generalmente las más altas, ya que la aplicación de métodós con relleno hidráulico tomado directamente de los relaves de la Planta, debe considerar la diferencia de nivel entre ella y los tajeos re-explotables.

Aug 20, 1965

By M. J. Ross, D. A. Norrgran, J. A. Wernham, J. N. Orlich

INTRODUCTION Laboratory testing for magnetic concentration circuit design is a requirement, just as it is for most other types of concentration. Natural variations in raw materials allow on1 y the broadest of generalities to be made regarding magnetic separation. Further, magnetic fields are geometry dependent, leaving fundamental models of a separator overly dependent upon the exact conditions for which the models were derived. Despite this, an understanding of the basics of magnetic separation and of the problem to be attacked can result in rapid progress towards the final circuit design with a relatively simple testing program. Magnetic Separation Basic Principles A magnetic field can readily be understood in terms of lines of flux. A familiar demonstration of these lines of flux is the pattern of iron filings on a sheet of paper when a magnet is placed underneath. Lines of flux2 are measured in Gauss (1 line/cm2) or Tesla (10000 gauss). Regions of high field strength have a greater number of lines. Field direction is indicated by a convergence of lines. When a particle is placed in a magnetic field it cuts the lines of flux and alters them in one of three basic patterns. These patterns are referred to as diamagnetic, paramagnetic and ferromagnetic. Diamagnetic materials have electronic structures which react to oppose an applied magnetic field. This opposition acts to locally reduce the applied field slightly. The visualization is that lines of flux diverge and go around the particle. Because of this divergence or opposition, a diamagnetic particle will tend to move towards regions of lower flux density. That is to say that the particle will be repelled by a magnetic field. Aluminum oxide and napthalene are examples of diamagnetic materials. Paramagnetic materials have an electronic structure which increases an applied magnetic field. Although these materials also exhibit diamagnetism, they have randomly oriented impaired electrons which align with the magnetic field. The resultant local field enhancement is significantly larger than the diamagnetic opposition. The visual-

Jan 1, 1986

New zinc fuming plant of the Cia. Metalurgica Del Norte S.A., a subsidiary of the American Smelting & Refining Co., nears completion at the Avalos Smelter, near Chihuahua City, State of Chihuahua, Mexico. The plant is scheduled for completion on July l, 1952. The erection contractor is Utah Construction Co. Supervising engineer for Asarco is Leslie E. Harris, AIME. [ ]

Jan 1, 1952

By F. K. Mulenga, M. Lusambo

"Geometallurgical models are a strategic tool used primarily in planning, diagnosis, and process optimisation. This paper discusses the development of a predictive model for flotation recovery at Kansanshi concentrator in Zambia as a function of key operational parameters. Daily data for milling and flotation from the circuit processing the copper sulphide ore was analysed. This data, recorded over a period of one year of production, was collected from diverse sensors measuring semi-autogenous milling and flotation parameters. Statistical analysis showed that copper head grade, acid-insoluble, and acid-soluble copper, SAG mill throughput, ball mill load, and tonnage of feed material to the SAG mill in the -125 +63 mm size fraction contributed to the prediction power of the proposed empirical model by as much as 90%. Finally, a proposal was made for the development of a simulation model under MODSIM®, a flexible tool for mineral processing applications. This was to test the limitations of the empirical model for future refinement. IntroductionKansanshi is the largest copper mine in Africa and the world’s eighth largest copper producer, with a total of 253 272 t of copper produced in 2016 (Newall, 2017). It is located approximately 10 km north of Solwezi, the capital and administrative headquarters of the North Western Province, Republic of Zambia. The ore deposit consists predominantly of chalcopyrite and malachite with variable amounts of chalcocite, bornite, chrysocolla, and azurite. Because of the varying proportions of sulphide and oxide copper minerals, the ore is classified into three distinct categories: sulphide, mixed, and oxide ores. As such, three separate processing circuits are used to mill the ore down to a standard targeted grind size of 80% passing 150 µm before froth flotation and leaching.A lot of research and development has been done to improve the performance of the sulphide ore circuit at Kansanshi. Despite the research efforts and subsequent operation, the sulphide ore circuit did not attain the target recovery and grade for 2016, primarily because of the complexity of the orebody.The constant drive to achieve the set production target of recovery and concentration grade after froth flotation motivated the development of a tool for the prediction of recovery. The anticipated benefit is not only to enable the plant to apply corrective actions when needed, but also to make a tool available for the quick assessment of the plant performance of the. For that purpose, data spanning June 2016 to May 2017 was analysed, cleaned up and curvefitted to an empirical model. In doing so, key parameters were determined and calibrated to represent the behaviour of the plant."

Nov 1, 2018

By Jan Van Greunen, Mark Vanderzee, David Haug, Geoffrey Hughes, Yiming Sun, Roozbeh Geraili Mikola

"The Sanitation Districts of Los Angeles County is planning to construct a new, approximately 7-mile-long (11.3 km) effluent outfall tunnel to be excavated by TBM and lined with precast concrete segments. Anticipated net operating pressures within the tunnel are expected to approach 3 bar. To counteract joint opening and exfiltration leakage, an approach has been investigated to post-tension the precast concrete tunnel lining with steel tendons. The tunnel alignment crosses several seismically active fault zones, at which installation of steel pipe is proposed as a secondary inner lining to mitigate potential offset displacements. This paper discusses the tunnel lining design approach and methods used to address these unique challenges.INTRODUCTION The Sanitation Districts of Los Angeles County (Sanitation Districts) is planning to construct a new 18-foot-diameter (5.5 m), approximately 7-mile-long (11.3 km) tunnel from the Joint Water Pollution Control Plant (JWPCP), located in the City of Carson, to the existing White Point outfall manifold structure at Royal Palms State Beach (RPSB) (Figure 1). The project is part of the Sanitation Districts’ Clearwater Program, which will improve overall system reliability through the repair and replacement of the existing aging infrastructure. The existing system includes two 6-mile-long (9.7 km) tunnels, 8- and 12-feet in diameter (2.4 and 3.7 m), and four ocean outfall pipes with a maximum capacity of approximately 675 million gal/day (MGD) (2.6 billion L/day). Addition of the new parallel tunnel will increase overall capacity to accommodate peak wet weather wastewater flows of up to 1,262 MGD (4.8 billion L/day) and will allow inspection and repair of the existing tunnels. The new outfall tunnel will be excavated using a pressurized face tunnel boring machine (TBM). Shafts at the north (JWPCP Shaft) and south (RPSB Shaft) ends of the proposed alignment will connect the tunnel to the existing wastewater treatment plant and existing ocean outfalls manifold and during construction act as launch and receiving shafts for the TBM. The tunnel will be excavated from north to south as a single heading."

Jan 1, 2016