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By H. G. Stephenson, C. W. Gregory

"This article describes the methods used for pillar extraction in the Wilson Seam at Canmore Mines, Alberta. The Wilson Seam is extremely gassy and varies in thickness between 7 and 30 ft, with an average of 12 ft. The gradient varies from 5 to 30 degrees, with an average of 15 degrees. The seam was developed using Lee Norse miners to form pillars which the company intended to extract using the same machines. Before pillar extraction commenced, an abandoned and inaccessible mine 160 ft above the Wilson had to be drained of 360 million gallons of water. When this was done pillar extraction commenced. Conditions in the mine slowly deteriorated and after 6 months the decision to withdraw the continuous miners was taken. Slusher hoists were installed to replace the continuous miners, with the result that roof conditions and safety steadily improved."

Jan 1, 1972

By J. HUNER

Twenty-four new fields were found in Louisiana during 1945. Of this number 15 were oil fields, eight were gas condensate, and one a dry gas field. None of these fields, with the exception of West Delhi, is as yet of any great consequence. The Weeks Island field in Iberia Parish may eventually develop into a considerable reserve.

Jan 1, 1946

By David D. Walker

The purpose of the investigation was to describe and appraise tungsten deposits in Montana . The work supplements previous investigations made by Pattee ( 10 ) and Walker ( 17 ) in selected areas of the State . Scheelite deposits in tactite are the most numerous and most important economically , having accounted for nearly all of the State's tungsten production . Of the 64 deposits examined during the current study , 50 contained scheelite , 11 hubnerite , 2 wolframite , and 1 ferberite . The State's major tungsten production has been from scheelite deposits in Beaverhead County . The report lists , by counties , the type and grade of each deposit . The more important occurrences are accompanied by geological and assay maps .

Jan 1, 1963

By C. A. Sosa-Blanco

Minera Sabinas in central Mexico treats a complex sulfide ore containing galena, chalcopyrite, sphalerite and argentite as valuable minerals, and in some cases important amounts of non-magnetic pyrrhotite. For high pyrrhotite ores, results obtained by selective flotation showed good grades and recoveries in the lead-copper circuit, but a commercial zinc concentrate could not be produced due to the high floatability of pyrrhotite. When this is the case, an alternative method was proposed to produce a bulk concentrate by flotation which is then leached to recover copper and zinc from liquor in a SX-EW circuit. Leaching was conducted in an autoclave in order to study the effect of temperature and pressure, but bioleaching tests were also conducted. Leaching lead-silver residues were treated by cyanidation in order to recover silver values. The results obtained by selective flotation and by bulk flotation with leaching of the bulk concentrate showed that the latter alternative increased zinc recovery by 30 % with similar recoveries of the other metals.

Jan 1, 2007

By Gary L. Simmons

Noranda's Grey Eagle Mine and Mill, located in the Siskiyou Mountains of Northern California, began shakedown operations in the late fall and early winter of 1982. This paper describes some of the unique features in mining, milling and water treatment operation at Grey Eagle. In addition, major start-up problems in the mill and water treatment plant are discussed along with measures taken to correct these problems.

Jan 1, 1984

By N. A. Tiner, Saara Asunmaa

The early stages of nucleation of vacuunz-deposited gold coatings on electropolished surfaces of pure nickel and binary alloys of Ni-A1 and Ni-Ti have been studied, employing carefully controlled temperature and vacuum conditions. The preferential nucleation of gold on slip-plane edges on the crystal surfaces gave rise to a very pronounced decoration effect which was used in studying the morphology of the pain boundaries, etch pits, and slip planes on crystal faces. Characteristic surface patterns were observed with local dimensional variations. Most pronounced geometric patterns were ohserved in the pain boundaries of nickel and on the crystal faces of Ni-A1 alloy. The nucleation behauior of gold indicates contamination on the Ni-T1 alloy and the getter properties of titanium are presented as a tentative interpretation for the detected contamination. The markings and imperfections on cleavage surfaces of crystals have long been observed by optical microscopy.1,2 Surface-replica techniques are also used to detect the smallest steps and structural details on crystal surfaces by electron microscopy. Recently, Bassett3-5 and Sella, Conjeaud, and Trillat 6 have shown that, when gold is deposited onto a rocksalt cleavage surface, there is preferential nucleation at steps and slip-plane edges on the crystal surface. This gives rise to a very pronounced decoration effect which is invaluable for revealing the lattice steps on a cleavage surface. According to Bassett,3 gold atoms arriving during vacuum evaporation at the crystal surface have a certain mobility on the surface after arrival, particularly at elevated temperature. If a significant

Jan 1, 1964

By W. E. Young

This paper describes operations of the Chief Consolidated Mining Co. at the Chief mine in the Tintic district, Juab County, Utah, where the outstanding problem is water control; the unique pumping methods employed are featured in this report. The ore bodies in this district occur as long, narrow shoots along fault fissures, usually in the Bluebell dolomite of Ordovician age. Oxide ores predominate above the 1800 level, which is also the natural water level. Sulfide ores containing lead, zinc, silver, and gold extend below the 1800 level. The mine is developed by vertical shafts and winzes, from which drifts are driven to the ore bodies. In the lower levels of the mine these drifts extend long distances from the shafts or winzes because of the relatively low dip of the ore shoots. The mine has been worked to the 2800 level and the 18-411 winze extends to the 3080 level.

Jan 1, 1958

Thank you chairman, good afternoon ladies and gentlemen. In my talk this afternoon I intend to cover a brief history, some of the recent experiences and an overview of the McArthur River project.If we consider the themes of this forum, Obstacles and Opportunities, I can confidently say that in attempting to develop the McArthur River deposit Mount Isa Mines Limited (MIM) must have encountered almost every obstacle that can be imagined. However the large size and the high grade of the deposit has ensured an opportunity, from which it is very difficult to walk away from.The McArthur River Here's Your Chance (HYC) Deposit is located in the Northern Territory of Australia. It was discovered by Mount Isa Mines Limited geologists in 1955 and is one of the largest known sedimentary stratiform zinc-lead-silver deposits. The deposit has been the subject of numerous investigations and considerable expenditure culminating in a major feasibility study in 1979. There were a number of factors which prevented development, these being the size of the project, the fine grained mineralization, geographical location, market, social and capital cost. The latter had been estimated in the 1979 study to be $800 million at that time.

Jan 1, 1993

This report describes the new Bureau of Mines Core Repository System (CORES) and presents the methods for selecting, processing, and storing physical samples and descriptive data for future reference by earth scientists. The system preserves splits of chip samples and longitudinally sliced segments of core. A records retrieval system provides for storage of data on microfilm and magnetic tapes and uses the keysort parameters of location and commodity for the identification of data.

Jan 1, 1978

By F. S. Thurner

This paper, a description of the new ore-unloading and stockpiling facilities at the Sydney Works of DOSCO Steel Limited, deals with a new approach to arrive at the most economical solution to combine ore unloading facilities for common bulk carriers and for different types of self-unloading vessels. Also discussed is the design and installation of a 1-mile-long steel-cord belt conveyor sys-tem with a most modern type of mobile belt conveyor stacker, along with automatic and semi-automatic controls for the entire ship-unloading and stockpiling operations.

Jan 1, 1968

By Teuku A. R. Putra, Patrick R. Taylor

Various pyrometallurgical methods for treating copper concentrates that contain appreciable arsenic are reviewed. Various aspects of the engineering of these treatment methods are discussed. The methods discussed include: complete oxidation with arsenic fixation; selective volatilization of arsenic; acid baking, soda ash roasting, and others methods. Methods for the ultimate disposal, or marketing, of the arsenic are discussed.

Jan 1, 2014

By J. G. Bennett

Coal consumption has increased globally by 57% over the last ten years. Underground mining typically provides coal of the highest calorific value and accounts for the greatest proportion of production. Despite a negative environmental image and indeed impact, this industry appears likely to thrive on the global scale for many years to come. Such mining consumes large amounts of electricity with implications for carbon dioxide emission at power plants and emits substantial quantities of the powerful greenhouse gas methane. In response to this significant carbon footprint, the European Union has funded research to examine the potential for a range of improvement technologies in a project entitled Low Carbon Mine Site Energy Initiatives (LOWCARB). Coal properties related to seams and mines, together with longwall characteristics, provide the basis for research into modelling optimally efficient methane drainage with a view to assisting mining as well as maximising electricity generation at surface and hence oxidation of the methane. Possible systems for the oxidation of very low concentration methane in ventilation air, which contributes the greatest greenhouse gas impact due to the volumes emitted, have been studied and modelled. Simulation and investigation of intelligent optimisation of electricity demand patterns provide the basis for reducing the demand peaks at mines and hence the cost and ultimately the carbon footprint of a mine, while specific investigations have been undertaken into ventilation efficiency at an unusually challenging mine and simulation of mine water pumping in order to develop an innovative method to monitor pumping systems efficiency. For post-mining use, the potential of disused shafts for compressed air energy storage to improve the operation of future electricity grids with high renewable energy penetration by reducing peak generation capacity requirements has been studied. While underground coal mining will always by definition be related to a significant carbon footprint, this paper provides an overview of a set of initiatives that can make a positive environmental impact while controlling costs across a huge global industry.

Aug 1, 2013

By Leandro de Almeida

Tiras e chapas de cobre e suas ligas possuem excelentes propriedades térmicas, elétricas e mecânicas simultaneamente e por isso podem ser utilizadas na fabricação de inúmeros produtos através de processos de conformação. Determinadas características devem ser analisadas na chapa antes mesmo do processo de manufatura, visando eliminar possíveis falhas durante as etapas de produção. Especificamente para o processo de repuxo profundo, faz-se necessário avaliar a possível formação de orelha e o possível afinamento da espessura da chapa durante a conformação. Sendo assim, o levantamento dos coeficientes de anisotropia planar ?r e o de anisotropia normal r são essenciais para se obter bons resultados nos processos de conformação. O presente estudo tem como objetivo avaliar a influência da deformação (e) na obtenção dos coeficientes ?r e r na liga UNS C22000, utilizada especificamente para a produção de projéteis A norma ASTM E 517 que apresenta a metodologia para se determinar esses coeficientes não especifica claramente qual e a ser utilizada. Os resultados alcançados não demonstram diferenças significativas com relação a e utilizada nos ensaios, ou seja, os coeficientes obtidos utilizando 0,10, 0,15 e 0,20 de deformação são os mesmos.

Aug 17, 2017

By R. L. Crosby

Microscopical and X-ray diffraction techniques were used to identify two intermediate phases in that part of the solid region of the magnesium-cerium system between and Mg3Ce. Previous literature had reported only one intermediate phase for this region, 1)12t chemical analysis determined the approximate composition of the two compounds to be Mg23Ce2 and Mg17Ce2. The range in composition of the two intermediate phases was found to be limited to less than 0.3 atomic percent cerium. The study did not determine the crystal structure of Mg17Ce2, but that of Mg23Ce2 is tetragonal with a = 10.33 A and c = 19.51 A.

Jan 1, 1966

By S. Zhao, S. P. He, M. Y. Zhu, Y. Tao

"The effect of two refining slags (A: 1.0–1.8 CaO/Al2O3 ratio, 11–20 wt% SiO2; and B: 1.0–1.2 CaO/SiO2 ratio, 25–35 wt% Al2O3) on the inclusion morphology of a carbon structural steel (Q235B) was studied by controlling the balance between the steel and the refining slag at 1600ºC in a Si–Mo resistance laboratory furnace. The results showed that most of the inclusions in the molten steel balanced with slag A were formed by a lowmelting CaO–MgO–Al2O3–SiO2 system with a total oxygen content (T[O]) being fixed at 6–13 ppm. The inclusions in liquid steel balanced with the slag B were mostly formed by the CaO–MnO–Al2O3–SiO2 system, with T[O] controlled to 19–26 ppm. The overall size of the inclusions under balance conditions was higher in the steel reacted with the slag B than that reacted with slag A, with the latter showing more inclusions smaller than 3 um. In order to generate a large number of spherical CaO–MgO–Al2O3–SiO2 inclusions smaller than 3 ??m while decreasing the T[O] in the resulting steel, the composition of slag A should be used. This composition allowed improving the cleanliness of the slab, and is also advantageous for the castability of the molten steel. IntroductionThe sample used in this study was a typical carbon steel manufactured by CQ Steel. The galvanized, tinned, and plastic composite steel plates made of the original plates are used extensively for decorative panels, general dust pipes, drums, instrument cases, switchboxes, and train cars, among other uses. The target control composition is shown in Table I. The S and P contents are usually fixed during production below 0.020 and 0.025 wt%, respectively, with the aim of reducing longitudinal cracks on the slab surface."

Jan 1, 2017

By F. Samimi Namin

One of the main tasks in exploitation of mines is to select a method suitable for the deposits, specific features including geometric, geo-mechanical and geological features. The purpose of selecting a mining method at this stage is to choose one or more method(s) having the most coordination with the deposit?s conditions and external factors, including the allocated budget and local technology for detailed feasibility studies. Several methods have been developed in the past to evaluate suitable mining methods for an ore deposit, based on its physical characteristics. These approaches can be classified into three groups: (1) profile and checklist methods, (2) numerical ranking (scoring) methods, and (3) decision-making models. Most of these methods have shortcomings. Considering the fact that most of the specifications of mineral deposits, such as dip and depth, are linguistic variables, absoluteness of the explaining parameters by previous methods can be mentioned as the most important disadvantage of these methods. This paper discusses the Fuzzy technique for order performance by similarity to ideal solution (Fuzzy TOPSIS) to determine the mining method. The fuzzy decision making (FDM) software tool is employed to develop a Fuzzy TOPSIS based model. Application of this model with various values (crisp, linguistic and fuzzy) of the deposit eliminated the existing disadvantages of other methods. Two empirical illustrations demonstrate the effectiveness and feasibility of the evaluation procedure. These show that the proposed model performs better than its alternatives. Keywords: mining method selection, fuzzy TOPSIS, decision making, mining engineering, linguistic variables.

Jan 1, 2008

By J. B. Littlefield

[A rulp has i~c+:r. ilrsi i,nsd Lo O~JPY:L~ e the mid~ol Llf;pin.5cr rll~!-t-.cxny)lin:: apparatus recently c',ov~-lo.pe;t by tL1e '.liro:ul of !dines- For th-is pilryoac, a po?.-iti~rs-nct.i?~. pvrni? t:,.;~t v:i.l.'l. :.-,,- #?,n c-noot'fl ;L flow nc possiY,].c? is dcni?.oYle. Flota.lS:r vnnc\-t:rre 1jl:~l~l: zrt iln~;xtJsY:or (2s thc:; n1lr.t ke tvrned at h ityh spet.d for rT:oot,c, o;?ey,;ltiori., ~nd at hi:,h s~ee(' the c8n:xcity oi' the s-n:r.llest piqt ott:~ir?:zk?e Is too la~-~:c. nir crrn'rle bler! in nt the intn?~, but t,he mm;nt o nor.;: l.o'q7r ir.:,l soon t ire:. the oyernt or]

Jan 1, 1938

By J. B. Littlefield

[A rulp has i~c+:r. ilrsi i,nsd Lo O~JPY:L~ e the mid~ol Llf;pin.5cr rll~!-t-.cxny)lin:: apparatus recently c',ov~-lo.pe;t by tL1e '.liro:ul of !dines- For th-is pilryoac, a po?.-iti~rs-nct.i?~. pvrni? t:,.;~t v:i.l.'l. :.-,,- #?,n c-noot'fl ;L flow nc possiY,].c? is dcni?.oYle. Flota.lS:r vnnc\-t:rre 1jl:~l~l: zrt iln~;xtJsY:or (2s thc:; n1lr.t ke tvrned at h ityh spet.d for rT:oot,c, o;?ey,;ltiori., ~nd at hi:,h s~ee(' the c8n:xcity oi' the s-n:r.llest piqt ott:~ir?:zk?e Is too la~-~:c. nir crrn'rle bler! in nt the intn?~, but t,he mm;nt o nor.;: l.o'q7r ir.:,l soon t ire:. the oyernt or, ]

Jan 1, 1938

By Marcel Bielefeld, Joost Bakker, Rob van Dorp

Pile load testing can be performed by a static, rapid or high strain dynamic (generally designated as dynamic) testing method. The static load test is often considered the “gold standard” of testing with the other methods merely ‘alternatives’. However, the rapid load test, as a quasi-static test, has all the positive elements of the static alternative: the direct measurement of loads and displacements. Moreover as stress wave phenomena have no influence, the interpretation of rapid load test results is more straightforward than that of dynamic testing, and also independent of the person performing the interpretation. This paper will explore the Rapid Load Testing method and illustrate the advantages and limitations through a case study in Rostock, Germany

May 1, 2022

By B. Pesic

The recovery of silver and gallium from flue dust with acidified thiourea solutions was examined. The studied parameters were temperature, particle size, thiourea concentration, acid concentration, and the presence of oxidants. The study of the extraction of these two metals was undertaken in sulfuric acid medium. Silver dissolution was dependent on all examined parameters, whereas gallium extraction was only dependent on the initial acid concentration. The experimental results suggest a new very efficient method for recovery of both silver and gallium. Almost complete recovery of silver and gallium can be accomplished within 90 minutes. A technological scheme for recovery of both metals is also proposed.

Jan 1, 1986