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By Pierre Gauthier

Is the hydrogen economy of the future just another fish story? Absolutely not! There have been many changes affecting the energy equation over the last 10 years and conditions have changed. In this presentation, we will examine the reasons why, in the very near future, hydrogen production and distribution will be increasingly visible on many industries? radar screens.

May 1, 2007

By Guilherme Vieira Braga Lemos

Uma superliga a base de Níquel, popularmente conhecida como Inconel 625®, foi estudada no presente trabalho. A Soldagem por Fricção e Mistura Mecânica (SFMM) aplicada a liga 625 foi realizada com velocidades de rotação da ferramenta entre 1200 a 200 rpm e velocidade de soldagem entre 1 e 1,5mm/s. O aporte térmico foi calculado como função dos parâmetros de soldagem empregados. Adicionalmente, análises metalográficas e de microdureza foram realizadas na seção transversal das juntas soldadas. A aplicação da soldagem no estado sólido foi efetiva e resultou em maiores valores de microdureza todas as juntas soldadas. Por outro lado, um aumento na velocidade de rotação causou um aumento do aporte térmico.

Aug 17, 2017

By Ana Carolina Fernandes Reis

O objetivo do trabalho foi investigar a recuperação metalúrgica da flotação de sulfeto de ouro utilizando diferentes tamanhos de partículas, a partir de ensaios de moagem e flotação em bancada, visando analisar o melhor desempenho e seletividade do processo. O minério em estudo apresenta um teor médio de ouro de 5,28 ppm e 0,59% de S. Nos testes verificou-se uma correlação diretamente proporcional entre a recuperação mássica e metalúrgica, ambas mostraram-se inversamente proporcional a seletividade no concentrado. A granulometria com 90% passante na malha de 0,053mm obteve o melhor resultado de recuperação tanto do ouro como de sulfetos, em contra partida, apresentou o menor grau de seletividade.

Aug 16, 2017

By J. B. Janus

In connection with the purchase of coal under specifications for Government use, the Bureau of Mines in this report has compiled data on 81 mines located in 15 States. This annual report lists analytical data on the composition and quality of tipple and delivered samples of coal collected during fiscal year 1973. Tipple samples were collected by Bureau of Mines engineers at tipples as coal was being loaded into railroad cars or trucks. Ultimate analyses are given for most of the coalbeds listed. The deliveries were sampled at destination in accordance with instructions issued by the Bureau of Mines. All samples were analyzed in the Bureau laboratory at Pittsburgh.

Jan 1, 1973

By P. K. Kaiser

3-D virtual reality (VR) visualization has opened new opportunities for complex 3D (x, y, z), 4D (x, y, z, t) or even nD data interpretation. The integration of common earth models (3D geologic data), mine models (3D excavations and stress), extraction models (1D time sequencing or mine sequencing) and nD monitoring data (e.g., seismic event parameters) into a common mining process model provides a platform for experts in various fields to better design, evaluate, monitor and modify mine plans throughout a mine?s life; from feasibility, through operation, to closure. Viewing seismic data in a stereoscopic VR environment within a mining process model offers data interpretation processes previously unavailable at lower dimensionality. MIRARCO has developed data analysis and viewing processes specifically designed to enhance microseismic and seismic data interpretation in a collaborative, immersive VR environment; bringing mine personnel and expert consultants together to evaluate data and make strategic decisions for cost effective and safe mining. Seismic events cause immediate hazards (rockbursts) and microseismicity causes gradual hazards through its cumulative effect in rockmass degradation. The focus of this paper is on understanding seismicity from a mine safety and mine planning perspective; in particular, how seismic migration patterns relate to the rockmass response to mining. The benefits of innovation in seismic data interpretation are significant, e.g., for hazardous work area identification, allowing better formulation of re-entry policies and workforce allocation planning, as well as allocation of effective support systems to strategic areas of elevated risk. Better understanding of the overall response of a mine to extraction also facilitates mine planning and design, assisting in reducing production costs and thus in enhancing profitability.

Apr 1, 2005

The primary purpose of the Institute is to advance the technologic and engineering arts embraced by it through interchange of knowledge This can best be done by the presentation and discussion of technical papers by its members Short practical papers are especially welcome An author should always satisfy himself that his material is of a quality that will be a credit to him and to the Institute The preparation of a good paper frequently leads to a reorientation of the author's thoughts, and publication contributes much to the professional standing of the author Members are urged to submit papers presenting the results of their work Attention to the following suggestions will greatly further the prompt and efficient handling of manuscripts

Jan 1, 1952

By Maria K. Kojo

The interaction between various slags and a nickel concentrate containing pyrite, pentlandite, and violarite were investigated by submerging concentrate pellets in molten slags. The slags were contained in MgO-A12O3 spinel crucibles. The slag oxidizes the iron sulfides in the concentrate, resulting in a nickel matte. The amount of S02 gas formed during reaction was measured to determine the oxidation reactivity of the slags. The experimental variables included temperature, the ferric/ferrous ratio of slag, and other slag properties such as the FeO/SiO2 ratio and the MgO and NiO contents. The reactivity of the slag depended in a complex manner on its oxidizing power, viscosity, and interfacial tension. The slag composition for the greatest reactivity was determined to be Fe3+/Fe2+ = 0.3, Fe/SiO2 = 1.3, and % MgO = 2. This slag, however, caused substantial foaming. Increasing the MgO content to 10% or replacing it by 5% MgO + 8% NiO eliminated at a slight decrease in reactivity. The implications of the findings from this work in the bath smelting of nickel sulfide concentrates are discussed.

Jan 1, 1995

Water conservation and compliance strategy can be cause for success or failure of a new or existing mining operation. Water accounting at outset, and pit and waste dump planning, may not fully consider total inflows, or sediment loads encountered during mine life. Environmental impact assessments, and permitting often dictates the rules, and these may change, to be more stringent, during course of mine development. This paper will identify techniques to control unprojected fresh water, or increased surface water flows in surface mine operations.

Feb 23, 2014

Discussion of the paper of E. G. Woodruff, presented at the Butte meeting, August, 1913, and printed in Bulletin No. 78, June, 1913, pp. 1001 to 1010. F. A. LINFORTH, Butte, Mont.:-I have not had an opportunity of reading this paper thoroughly, but I would like to call attention to the possible use of the contours on fault planes. It is obvious that if the contours of fault surfaces call be determined, we will be able to determine the axes of the hollows in the fault surface. It seems probable, and there are examples to point to the accuracy of, the assumption, that the axes of these hollows may be the direction of movements on the faults, and if that is true it will aid materially in locating faulted ore bodies or the shoots of ore on the opposite sides of faults. A few such contour maps of faults have been attempted on some of the faults of the Butte district, and those faults which are believed to have the nearly normal movement exhibit for the axes of these hollows a line nearly up and down in the plane of the fault, but in those cases where the throw is believed to bee nearly horizontal we find that the axes of the hollows are almost horizontal lines. In other words, the movements on faults, I believe, would be more nearly indicated by the larger grooves in the fault surfaces than by the small slickensides and minor hollows that are seen, so that contour maps might be valuable in geology in that way. C. W. GOODALE, Butte, Mont.:-I received a letter from Mr. Woodruff asking me to take part in the discussion of his paper, but I have not had time to give the paper any study. I can certainly add my opinion to that of all the engineers here that the topographic maps of the government are of great aid to the engineer. When I visit a new district, the first thing I do is to see if that district has been covered by the U. S. Geological Survey avid if topographic map has been issued. And I find that some of the younger engineers frequently come into my office to see if I have such maps. I know in some cases the reports made out by engineers contain copies of these topographic maps, or clippings from them. I am sure that. the topographic maps furnished by the government are of very great value to our engineers.

Jan 11, 1913

By P. T. Bissert, L. Yan, M. D. Klein

"Federal regulations require that refuge alternatives (RAs) are located within 305-m (1000-ft) of the working face and spaced at one-hour travel distances in the outby area in underground coal mines in the event that miners cannot escape during a disaster. The Mine Safety and Health Administration mandates that RAs provide safe shelter and livable conditions for a minimum of 96 hours while maintaining the apparent temperature (AT) below 35°C (95°F). The National Institute for Occupational Safety and Health used a validated thermal simulation model to examine the mechanisms of heat loss from the RA to the ambient mine and the effect of mine strata composition on the final internal dry bulb temperature (DBT) for mobile tent-type RAs. The results of these studies show that most of the heat loss from the RA to the ambient mine is due to radiation (51%) and conduction (31%). Three mine width/height configurations and three mine strata compositions were examined. The final DBT inside the RA after 96 hours varied less than 1°C (1.8°F) for the three mine width/height configurations and less than 2°C (3.6°F) for the three mine strata compositions. INTRODUCTION Following a mine disaster, workers will try to escape the mine. If their escape is futile, they can take shelter in a refuge alternative (RA). In 2008, the Mine Safety and Health Administration (MSHA) mandated RAs in mines to ensure that a safe and livable shelter is provided for a minimum of 96 hours, and that the apparent temperature (AT) does not exceed 35°C (95°F) inside the RA [1]. An ongoing concern with RAs is the potential to exceed this limit. The temperature rise inside an RA is due to the metabolic heat released by the occupants as well as heat released by the carbon dioxide scrubbing system. The National Institute for Occupational Safety and Health (NIOSH) tested a 10-person tent-type training unit RA in its Safety Research Coal Mine (SRCM) to investigate heat buildup in RAs. The 10-person capacity for the tested RA is based on 1.4 m2 (15 ft2) of floor space per miner. NIOSH-developed simulated miners, which are heat input devices that generate both sensible and latent heat, were used to represent the metabolic heat generation of an average miner (117 W) for testing in the SRCM. It was found that the number of occupants in an RA may need to be reduced based on the ambient mine temperature, which varies from mine to mine [2]. To further research temperature rise inside an RA, ThermoAnalytics, Inc. (TAI) was contracted by NIOSH to perform thermal simulations of the tested 10-person mobile tent-type RA. TAI developed a thermal model of the SRCM using RadTherm software, which incorporates a human thermal model (HTM) to represent the equivalent metabolic heat loss of a miner within the RA’s enclosed environment. The thermal model was previously validated by comparing simulation results with test results [3]. During a mine disaster in which miners would have to take shelter in an RA, mine ventilation may not be available. As such, mine ventilation was off for both the testing in the SRCM as well as in the simulations. This paper discusses the heat loss mechanisms and the effects of mine strata composition and mine width and height associated with a ten-person tent-type RA."

Jan 1, 2016

By Marcos Paulo Kohler Caldas

A recuperação de metais presentes em equipamentos eletroeletrônicos tem atraído interesse em virtude de novas e diferentes tecnologias que visam a reutilização desses elementos químicos em novos processos produtivos. A recuperação de metais das placas de circuito impresso tem atraído o interesse das empresas, pois, ao mesmo tempo que produz bons resultados do ponto de vista econômico, também se pratica o desenvolvimento sustentável, reduzindo a extração de metais da natureza. Este trabalho tem como objetivo caracterizar as placas de circuito impressos (PCI’s) de memória de computadores, através de imagens de microscopia eletrônica de varredura com espectroscopia por dispersão de energia (MEV/EDS), a fim de verificar a presença de metais, visando a sua recuperação.

Aug 17, 2017

By M. Popescu

In the southern part ?f the Occidental Carpathians an iron ore body embedded in crystalline schist was exploited. The presence of minerals such as magnetite, pyrite, pyro-chorine, allanite, monazite and xenotime, which also include within their structure substituted thorium isomorphic, was pointed out. The iron ore was processed by crushing, grinding and magnetic separation in order to obtain magnetite concentrates. The environment was affected by pollution generated by the mining activities. In 1995 due to the economic reasons, it was decided to cease mining exploitation and remediate the area. The paper presents the ecological impact caused by mining activities on a number of environmental targets and the population. The pollution sources, namely sterile dumps and mine waters are characterized (from the physical, chemical and radiometric point of view); the pollution pathways and theirs effects on potential targets, namely soil, vegetation, hydrographic network and population are identified as well. The degree of pollution due to all sources was assessed and maps of pollution sources distribution were generated. The supplementary effective doses for the population were assessed using rigorous scenarios and considering all exposure pathways. The rehabilitation plan includes solutions for dumps geometrization, covering and revegetation as well as mine waters management.

Jan 1, 2005

By Charles G. Crans, Naresh Gurpersaud

"Toronto’s Union Station, a National Historic Site occupying an entire city block, is the busiest commuter rail transportation hub in Canada. An extensive project is being undertaken to revitalize Union Station while maintaining the historical significance of the building and minimizing disruption to commuters. A significant stage of the revitalization involves excavation indoors, to a depth of up to 5.5 m below the existing floor level to create space for a new transit concourse and a new lower-level pedestrian retail concourse. A hybrid excavation support system utilizing micropiles as soldier piles was constructed over an 18 month period between 2010 and 2011.Development and testing of connections between the micropiles, shotcrete facing, lagging, walers, and tiebacks presented significant challenges. The existing viaduct structure was constructed in the 1920’s on land reclaimed from Toronto Harbour, so there was significant (and ongoing) uncertainty with respect to buried obstructions including relic timber wharfs and abandoned steel and timber piles. Collectively all these conditions precluded the use of conventional methodology; new techniques, installed using modified equipment, and for the first time in the Greater Toronto Area, were required.Details of the existing site conditions, installation challenges, design, construction and performance of the hybrid excavation support system inside this historic structure are presented.INTRODUCTIONUnion Station in Toronto, Ontario is the busiest passenger rail facility in Canada, with 65 million passengers annually and an average of 200,000 passengers each day. Construction of the station was completed in 1920. It has been designated a National Historic Site of Canada and inducted into the North America Railway Hall of Fame in the Facility and Structure category.The Union Station Revitalization Project (USRP) was tendered in 2010 and awarded as a 6-year, $450M construction management / trade contract package. Included was a large scale grade reduction, referred to as “The Dig Down”, to create two basement levels and this required extensive excavation support constructed entirely indoors within the active station setting."

Jan 1, 2017

By E. F. Raffo

THE design of the Chuquicamata concentrator offered an unusual combination of problems, all of which had, in one way or another, a definite effect upon the final arrangement of all the equipment and necessary facilities. First of all, a remotely located project of this magnitude required careful selection of equipment with an adequate supply of replacement parts and in some cases necessitated stand-by spare equipment ready for immediate use. Fortunately, in the course of determining the proper flowsheet, in itself a prime factor in the concentrator design, it was possible to conduct numerous grinding and flotation tests at the Anaconda and Andes concentrators. As a result of these tests made under actual operating conditions, most of the major equipment best suited for treating the Chuquicamata ore efficiently was decided upon while preliminary design layouts were still being made. The design has been based primarily on the treatment of sulphide ore crushed to about 3/4 or 1 in. However, until the new sulphide crushing plant is completed it will be necessary to handle ore crushed to 3/8 in. in the existing oxide crushing plants and to some extent a mixed ore which has had its oxide copper content removed by leaching. This mixed ore, known as leached residue, will contain a certain amount of sulphuric acid from the leaching process which necessarily requires special protective measures. Several factors influenced the final location of the Concentrator. The only established fact known during preliminary design layout was the elevation of the dumping floor over the fine ore bin. This was predetermined by the desired level railroad grade across part of the existing tailing and leached residue dumps from the oxide plant to the bin. Next it was necessary that a site be chosen that would not require an excessively long haul from either the present oxide plant or the mine and in addition provide a fairly constant natural ground slope sufficiently wide to accommodate the length of the ultimate concentrator. The site as finally chosen to meet the foregoing restrictions provided a natural ground slope of 6 to 7 pct. This was excellent, especially in a region subject to earthquakes, as it assured that foundations of heavy equipment and footings for building and crane columns would rest on cut or undisturbed ground. However, this shallow slope, although having some definite advantages in the overall consideration of plant layout, resulted in the need for extensive studies in the general arrangement of equipment. Wasteful and excessive vertical drops had to be eliminated in the

Jan 1, 1952

The primary purpose of the Institute is to advance the technologic and engineering arts embraced by it through interchange of knowledge. This can best be done by the presentation and discussion of technical papers by its members. Short practical papers are especially welcome. An author should always satisfy himself that his material is of a quality that will be a credit to him and to the Institute. The preparation of a good paper frequently leads to a reorientation of the author's thoughts, and publication contributes much to the professional standing of the author. Members are urged to submit papers presenting the results of their work. Attention to the following suggestions will greatly further the prompt and efficient handling of manuscripts.

Jan 1, 1944

By J. G. Kirby

According to the Bureau of Mines annual survey, there were 318 petroleum refineries in the United States with a total daily crude throughput capacity of 8,632,390 barrels as of January 1, 1956. Compared with the previous year the total number of refineries declined 8 while the crude throughput capacity increased 211,760 barrels daily. Three refinery districts accounted for 90 percent of the crude-oil capacity increase, the California district 34 percent; the Texas Gulf Coast district, 31 percent; and the Indiana-Illinois-Kentucky district, 25 percent. Decreases in capacity during the year were reported for the East Coast, Appalachian #1, and the Arkansas-Louisiana Inland districts. The capacity of the average refinery to process crude oil increased during 1955 from 25.830 barrels daily to 27,145.

Jan 1, 1956

By M. Hesham El Naggar, Maged A. Abdlrahem

"Hollow bar micropiles have constructional advantages such as: fast and low-noise and low vibration installation process and small installation equipment, which allow access to tight places. In addition, they have efficient load transfer mechanism, which facilitates carrying considerable load in compression and tension. The common practice is to use diameter ratio of drill bit/ hollow bar (Db/Dh) around 2 in their construction, and they are typically designed assuming type B as classified by the Federal Highway Administration (FHWA). In this paper, the performance and capacity of Hollow bar micropile with different (Db/Dh) ratios are investigated. Full-scale micropiles were installed at a site in Ontario, Canada, and were tested in order to evaluate the uplift performance of Hollow bar micropile with different(Db/Dh) ratios. Two micropiles with two different ratios 2.25 and 3 were constructed and tested. The total length of the micropiles was 6m with embedded length of 5.75m. The soil at the site was primarily medium dense to dense sand. The results of the load tests are presented and discussed. It was found that the uplift capacity of the micropile increased by about 19.5% as Db/Dh increased from 2.25 to 3.INTRODUCTIONMicropile is a small diameter, less than 300 mm, drilled and grouted pile and is typically reinforced according to Federal Highway Administration (FHWA, 2005). The technology of micropile was introduced in North America in 1970’s, but the growth in the east coast of United State was intense compared to all other cities around the globe (Bruce and Nicholson, 1989). Nowadays, micropile construction is used extensively worldwide as a viable solution that offers several advantages such as fast installation in low headroom, minimal disturbance to the adjacent structure efficient load transfer due to high grout to ground bond strength. As the method of grouting has major influence on the grout – ground bond strength, FHWA has classified the micropiles into four categories. Type A: the grout is placed under gravity and no pressure is required. Type B: The grout is typically pressurized under a pressure range from 0.5 to 1 MPa as the temporary casing is withdrawn. Type C: the grout is placed in two-step process. First, the grout is poured under gravity only as in Type A. Before the hardening of the grout, similar grout is pressured of at least 1MPa without the use of packer. Type D: Like Type C, it is a two – step process, the grout is placed under gravity as in Type A and sometimes pressurized as in Type B. After hardening of the initial grout, additional grout is pressurized between 2 to 9 MPa through sleeved pipe by using packers, as many times as needed. According to this classification, hollow bar micropile is usually designated as Type B. However, the construction technique is completely different from Type B. Recently; there is a trend to supplement the four types of micropiles by Type E as represent to hollow bar micropile (Timothy et al, 2012). The construction method of hollow bar micropile involves two main stages which can be performed in one–step process: advancing the drilling bit attached to a threaded hollow bar to the required depth; and pressurizing the grout through nozzles of the drill bit."

Jan 1, 2016

By AIME AIME

WHEN Vice-chairman Calvert Townley calls the next meeting of the Executive Board of the American Engineering Council of the Federated American Engineering Societies to order in Washington on Sept. 30, it will be the first meeting in that city for almost a year. It is probable that the Board will decide at this meeting whether future board meetings will be held regularly at the headquarters in Washington or whether the plan of meeting at various engineering centers throughout the country, as has been done during the past year, will be followed. The most important business coming before this .meeting will be the election of a president to succeed Herbert Hoover, who resigned after he became Secre¬tary of Commerce. Nominations to fill this vacancy were ordered 'at the last meeting of the Executive Board, to be reported at the September meeting. Special attention will be given the plans for the engineering assembly, extension of employment service, question of licensing and registration of engineers. The engineering assembly, committee has been appointed, with A. P. Davis as chairman, the other members being Philip N. Moore, L. P. Alford, John C. Hoyt and F. A. Vaughn. This committee will work out detailed plans for an assembly to be held in con¬junction with the annual meeting of the American Engineering Council in, January. Tentative plans provide for a three-day session; one day to be given to special meetings of the executive boards of member organizations and committees of the American Engineering Council; one day to the sessions of the American Engineering Council; and at least one day to discussion of some, special topic.

Jan 1, 1921

By S H. Li, H Z. Gu, A Huang

High aluminium steel is a promising advanced steel known for its exception properties and holds significant economic and strategic importance. However, the CaO-Al2O3-SiO2 based slag with high alumina content reacts vigorously with alumina refractories during the smelting process at high temperature, seriously affecting the safe and efficient production of furnaces and resulting in the formation of Al2O3-MgO non-metallic inclusions within the molten steel. This is a bottleneck problem for high-quality steel refining, and the key reaction path during the corrosion remains unclear. The dissolution reaction mechanism of alumina refractories in high alumina CaO-Al2O3-SiO2 slags under a weak static magnetic field was investigated in this work, using high temperature laser confocal microscopy and in situ radiation spectroscopy techniques. The results indicate that the interaction between the high alumina slags and the alumina refractories is governed by free radical reactions. The dissolution of alumina forms AlO and AlO2 radicals. The reaction rate increases with the C/S ratio of the slag due to its low polymerisation. The reaction between non-bridging oxygen and AlO2 free radicals accelerates the generation of AlO and O2ꞏ- radicals. The reaction layer composed of calcium aluminate is formed through the recombination of AlO, Caꞏ+ and O2ꞏ- radicals. The weak static magnetic field induces the Zeeman splitting of free radical pairs and intersystem crossing occurs, promoting the formation of triplet free radical pairs through the hyper-fine coupling effect. The reaction can be significantly inhibited as the triplet free radical pair does not meet Pauli’s incompatibility principle. This discovery perfects the structure theory of molten slags with radicals and provides supplement to the design of the highly slag-resistant refractories, and provides the theoretical basis for the development of external field protection technologies for high-quality steel refining.

Jun 19, 2024

Coal Division Industrial Minerals Division Minerals Beneficiation Division Mining, Geology and Geophysics Division Council Will Mitchell, Jr, Chairman (MBD), Kenneth L Cook, Vice-Chairman (MGGD). Edward L Clark (MGGD), Raymond B Ladoo (Ind Min Div), Sandford S Cole (Ind Mm Div), Norman L Weiss (MBD), C T Hayden (Coal), H F Yancey (Coal), Clayton G Ball (MED), P De Bruyn (MIED), Arnold Buzzalini, Secretary, AIME, 29 West 39th Street, New York 18, N Y Mining Branch Advisory Committee Will Mitchell, Jr, Chairman, Grover J Holt, J B Morrow, J L Gillson, Edward G Fox, S S Cole, Roger V Pierce, Norman L Weiss. H C Weed. J R Van Pelt

Jan 1, 1956