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By A. Soderberg

This paper describing the mining practice at the Utah Copper Co., Bingham Canyon, Utah, is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The Utah Copper Co. operates the low-grade open-out copper mine at Bingham Canyon, Utah, which is 30 miles in a southwesterly direction from Salt Lake City. In addition to the mine the company operates two flotation concentrators, the Magma plant and the Arthur plant, which have a combined capacity at maximum metallurgical efficiency of 60,000 tons daily. The concentrators are at Magna, about 18 miles from the mine. The company operates its own standard-gage railway, known as the Bingham and Garfield Railway, between the mine and the mills (fig. 1). Concentrates are smelted at the Garfield smelter of the American Smelting and Refining Co., situated 4 miles from the mills.

Jan 1, 1930

By Richard Collins

The projected depletion and the increasing costs of petroleum and natural gas along with the public and governmental resistance to nuclear energy have caused coal to emerge as one of today's answers to both our short term and long term energy needs in power generation. In order to satisfy this need, major increases in coal production are mandatory, thus requiring more and higher capacity coal transfer terminals. The logic for selecting coal as the major fuel for power generation is based on many different reports on the existing and potential energy sources, which include petroleum, natural gas, hydropower, solar, geothermal, and nuclear. The following is a brief synopsis of these reports for each type of energy.

Jan 1, 1978

By Alexander J. Verstraeten

The design and construction of foundations for power transmission line towers present some special problems. This paper describes a system of design and construction for these foundations that was developed in Europe and has attained general use there because of its reliability and cost effectiveness. Transmission line foundations distinguish themselves by having to deal not only with compressive and lateral loads, but with uplift loads and, because of the wind (in some regions earthquakes), with dynamic loading. The construction of transmission line foundations distinguishes itself mainly in the great number of inaccesible locations involved, resulting in extensive geotechnical investigation and logistical problems in moving men, materials and equipment.

Jan 1, 1987

By D. A. Bruce

The Deep Mixing Method is a very valuable tool for combating problems related to in situ soil treatment, improvement, and retention. Many different variations are used throughout the world, and there is a correspondingly rich technical literature on the testing and properties of the treated soil. This paper provides a synopsis of these aspects.

Jan 1, 2001

This report summarizes the work performed under USBM Contract No. H0395041. The primary objective of this work was to extend the noise control technology developed under earlier USBM projects to a wider range of load-haul-dump models to evaluate the general applicability of these techniques. Noise control treatments were designed, fabricated, and installed on three Wagner LHDs (an 5T-2B, ST-2D, and an 5T-8A) selected as demonstration machines for this project. The machines were evaluated either in production mines or at the Bureau's Lake Lynn Mine. The results indicate that it is possible to achieve overall noise reductions of between 4 and 8 dB using these techniques. Engine cooling and seal design were determined to be important design issues in such treatments.

Jan 1, 1984

By D. Vogt

A brief summary of the propagation characteristics of rock provides the necessary understanding to design effective radar surveys. Measurements of the electrical properties of the major Bushveld platinum-bearing horizons and their host rocks show that radar is an excellent tool for both short -and longer-range mapping. Experimental work confirms the performance predictions. High frequency, 500 MHz ground-penetrating radar (GPR) is a first-rate tool for mapping features in the hangingwall of the orebody, locally known as a ?reef?, for the purposes of determining hangingwall stability. The triplet chromitites above the UG2 have been clearly mapped, as has the Leader Seam above the UG2. Borehole radar at lower frequencies has been used over longer ranges to map reef elevation. Potholes in the UG2 are clearly distinguished in range and elevation to within metre accuracy. The nature of the slump in the various footwall horizons is also apparent. In future, as GPR is routinely applied, it is likely to become used for other purposes. Borehole radar is being developed to operate at higher frequencies, which will allow it to be deployed from boreholes that are within 5 m of the target horizon. Keywords: GPR, borehole radar, Bushveld Complex, UG2, Merensky, pothole, triplet

Jan 1, 2005

By H. Vigil Fernandez, G. Peach

The Musaimeer pump station and outfall project located in Doha Qatar, was designed to collect and manage ground and stormwater and then discharge the treated waters offshore. The project constructed a long outfall tunnel using an EPB TBM with segmental lining, each tunnel ring being 1.35 m in length with an internal diameter of 3.7 m.. The diffuser structure was a 6-arm structure, measuring 294m by 40 m connected to a central manifold in turn connected to the TBM constructed tunnel via a riser shaft drilled from an off-shore barge. This technical paper will discuss the planning, methodology and construction practices employed to connect the TBM tunnel to the diffuser structure 10.2 km offshore.

Jun 13, 2023

By Charles H. Shamel

I fear most of the Institute members are already weary of the perennial controversy about the apex law. I feel that way about it myself now, though I have been guilty of considerable contribution- to the discussion in the past. The discussion does not seem to perceptibly influence previously held views and I would not again break into print on the subject but for the urgent invitation of the Chairman of our Law Committee. This energetic and able member has firmly determined to secure a revision of the mining law and among other things to eliminate the so-called apex provision from the U. S. mining statutes. He is, however, fair about it and has invited me to make ((the strongest possible argument in its favor." I am suspicious that he is acting on the psychological principle that it is usually easier to convince an audience against a cause vigorously but unsuccessfully defended than against one wholly mute. Nevertheless, I realize that personally he wishes me no harm, much as he hates the apex law, and so am willing that the Institute have whatever benefit may accrue from my taking up again the unpopular side of the discussion. I say this because the attitude of a large part of our "articulate" membership seems irreconcilably hostile; their minds are made up; favorable consideration is foreclosed; and they become impatient and even sarcastic at any attempt to elucidate a favorable view of the apex law. The exact question for discussion at the present time is not whether on abstract, or any other considerations, the apex law is the best possible rule, but the very different proposition whether, after nearly 50 years of statutory life and much longer as a practically universal miners' custom, it is now just and expedient to repeal the apex law. At this point it seems to me that we may profitably devote a paragraph or two to the subject of the origin of law in general, as we are presumed to be considering the subject from the high viewpoint of the general welfare of the nation. The most comprehensive and accurate definition of law in the legal sense is, that it is the body of rules for the regulation of human conduct which is enforced by the State, that is, by the nation.l Legal

Jan 1, 1915

By Guerold Sergeevitch Bobrovnitch

Amostras de polifurfural (FH) obtidas por catálise ácida foram termobaricamente tratadas em várias temperaturas e sob pressão de 6GPa em um dispositivo de alta pressão do tipo bigorna com concavidade central. Após o tratamento cada amostra foi submetida a análise por microscopia eletrônica de varredura. Os resultados indicam que a FH é um material grafitável e, possivelmente, poderá ser utilizado como matéria-prima para a execução do processo de síntese.

Aug 16, 2017

By W. R. Bacon

"IntroductionTHIS IS a brief discussion of certain regional and economic aspects of the Coast Range of British Columbia. Between Portland canal and the 60th parallel of latitude, only the eastern margin of the Range is in Canada. The solely British Columbia interval extends from Portland canal to Burrard inlet. Personal observations in various parts of this area form the basis for much of this paper.Regional GeologyGranitic RocksSome of the best, most continuous exposures in the Coast Range are found at sea level. Reconnaissance study of the coastline has shown that the Range is predominantly granitic in character, but there simplicity ends, for the term 'granitic' as applied to the Coast Range covers a variety of mineralogical compositions. Actual granite is quite uncommon, occurring mainly in irregular or dyke-like masses that do not achieve batholithic dimensions. It is commonly pinkish, relatively homogeneous, and exhibits few of the deformational features that are obvious in much of this plutonic complex.Most of the granitic rocks of the Range fall well within the compositional limits of quartz diorite and granodiorite. The problem of resolving the great mass of these rocks into smaller coherent units is in general a difficult one. As noted above, granitic rock of uniform composition and texture is found in restricted areas and can be outlined without much difficulty. One such body occurs on the southern shore of Nelson island."

Jan 1, 1955

By D. R. Tesarik

The factor of safety, the traditional measure of stability for earth embankments, is graphically presented in factor of safety charts in this Bureau of Mines report. Factor of safety contours are drawn for homogeneous earth embankments for two contrasting situations: (1) no phreatic surface and (2) a phreatic surface that assumes 10-pct freeboard. The factor of safety can be read directly from the charts if the physical properties of the soil and the geometry of the embankment are known. The curves provide a quick first approximation of the "most stable" and "least stable" condition of the embankment. The Simplified Bishop Method was used for the safety factor calculations, and a sequence of least squares curve fitting steps was used to present the factor of safety in final chart form.

Jan 1, 1981

By B. S. Xakalashe

Keywords: Pyrometallurgy, silicon, solar cells Silicon has been the dominant material in the photovoltaic (PV) industry since its application in the space industry in 1958. This review focuses on crystalline silicon solar cells, primarily due to their dominance in the photovoltaic industry, omitting other photovoltaic cell technologies such as second generation (e.g. thin films) and third generation (e.g. nano-structured solar cells). The value chain for the production of crystalline silicon solar cells has been reviewed. The primary processing steps for the production of silicon solar cells from quartz are as follows: bulk production of metallurgical-grade silicon via carbothermic reduction in a submerged furnace, refining of metallurgical-grade silicon via the chemical means to polycrystalline silicon, or through the metallurgical route to solar-grade silicon, wafer manufacturing, and, lastly, silicon solar cell manufacturing. During downstream processing, solar cells are interconnected and encapsulated into solar modules (panels), which can be used individually or incorporated into a photovoltaic system for electricity generation and supply. The cost for crystalline silicon based solar cells is approaching one US dollar per watt peak ($1/Wp), while the most cost-effective solar modules in industry have reported costs below $1/Wp, and are based on CdTe thin films. Solar cell energy conversion efficiencies as high as 22% have been reported in industry for crystalline silicon solar cells.

Jan 1, 2011

William B. Phillips, Birmingham, Ala.: The analysis of Pratt coal made by myself, and given by Mr. Ormsbee in his paper (p. 113), is likely to mislead the reader as to the real nature of this coal. It represents the very purest coal that I have been able to get, and does not represent the average composition of the lump-coal as prepared for market. I wish it were true that the coal had no more than 2.50 ash and 0.83 sulphur. The analysis of McCalley is nearer the real figures than any of the others. There is no use in giving an

Jan 1, 1896

By Neill A, O&apos

The City of Kalgoorlie/Boulder is situated approximately 600 kilometres to the east of Perth (Fig. 1), and is the major regional centre of the Eastern Goldfields, supporting a population of approximately 25,000. The formation of Kalgoorlie Consolidated Gold Mines in 1989 brought the existing operat- ing entities adjacent to the city under common ownership and management. The Joint Venturers forming the management company are Homestake Gold of Australia and Gold Mines of Kalgoorlie (a Normandy/Poseidon com- pany). This traditional underground mining centre has been worked since 1893, yielding 40.8 million ounces of gold from ore with an average head grade of 10 grams per tonne. Historically the heart of the operation has been the famous Golden Mile located on the Eastern perimeter of the city, in the area known as Fimiston. The other significant operations that form KCGM are the Mt Percy Open Pit and the Mt Charlotte Underground Operation. KCGM's current production is 520,000 ounces per year, with the com- bined Fimiston operations (open cut and underground) contributing 400,000 ounces. The current expansion will increase production levels by a further 150,000 ounces. Traditionally 98 per cent of gold has been sourced from underground areas, however the recent upsurge of open cut operations is rapidly overturning this historical relationship.

Jan 1, 1991

By Douglas B. Silver

Study Parameters (Status as of February 1993) Time Period: 1989 -1991 151 North American Public Metal Mining Companies Fiscal not calendar year basis 85+% of Canadian and U.S. Metal Production Au, Ag, Cu, Pb, Zn, Mo, Ni, W Results are Preliminary and Research Continues Chicken Little is Alive and Well

Jan 1, 1993

By Altemar Dettogne do Nascimento

A Máquina de Lingotamento Contínuo nº 1 da ArcelorMittal Tubarão (AMT), com capacidade nominal de 1,8 milhões de toneladas/ano, teve seu start up em 1995. A máquina é curva com raio de 10,5 m. São produzidas placas de 200, 225 e 250 mm, largura de 800 a 1650 mm e velocidade até 1,7 m/min. Em Abril de 2012, a Máquina parou para uma reforma geral. A empresa Italiana Danieli Davy Distington foi contratada para fornecer a engenharia, fabricação e entrega dos equipamentos no período de 12 meses. No ano anterior à parada da máquina, foi realizado um site survey, o que possibilitou a elaboração de um planejamento detalhado de todas as atividades. A reforma da máquina teve como objetivos principais: correção do alinhamento da máquina, substituição de estruturas oxidadas, implantação de novas tecnologias e redução do tempo de exposição dos operadores a ambientes agressivos (alta temperatura, projeção de aço, queda de cascão da panela e material particulado) através da implantação da sala remota de controle dos veios. A máquina foi colocada em operação em 10 de agosto 2012 após ter completado, sem desvios, as fases de instalação e testes. Este trabalho mostra as fases de desenvolvimento deste projeto, os resultados das tecnologias implantadas e os testes de performance para diferentes famílias de aço.

Jul 29, 2018

By R. V. Ramani

Procedures have been developed which permit determining in either existing or new mines the optimum diesel equipment deployment schemes and the effect of. diesel exhaust on mine-air quality. Specifically, the following areas are covered in the report: 1. Description of diesel deployment schemes in four underground coal mines that were visited is provided. 2. Description of the analysis procedure to determine the number of shuttle cars required to maintain maximum theoretical continuous miner (or loader) production rates in typical room-and-pillar mining systems and of exhaust contamination resulting from the deployment of diesel powered shuttle cars are provided. Sensitivity analyses to determine the effect of changes in input variables on production and contaminant concentrations are also discussed. 3. Description of the analysis procedure to develop the locomotive operating parameters is provided. Assessment of both production performance as well as estimates of the magnitude of diesel exhaust contamination of the mine air are also made. 4. Recommendations for extensions of this research are outlined and include developing and testing procedures for 1) determining equipment duty cycles for the diesel equipment, and 2) studying the exhuast contamination of mine air on the basis of these duty cycles.

Jan 1, 1978

Flawed mining studies have been major contributors to poor investment decisions in mining for many years, contributing to the long period of poor industry profitability. Most of the major mining houses have now adopted quite formal processes and quality standards for mining studies to reduce the potential for poor investment decisions in the future. Other organisations such as the World Bank also have specific requirements for particular types of studies, such as bankable studies. This increasing requirement for rigour and discipline means a highly structured and phased sequence of studies is now required along with the development and adoption of industry-wide standards in mine ventilation studies. New terms in the study process such as ?independent peer review? and ?hold and review? are assisting in this process. More traditional terms such as ?feasibility study? and ?pre-feasibility study? now have much more precise technical definitions. Specific standards for the ventilation components of the various phases of a mining study are proposed in this paper.

Jan 1, 2009

By B Flynn, P Knights

Low-loaders or 'floats' for relocating equipment in surface mines are limited to a capacity of approximately 350 t. In the iron ore industry it is desirable to be able to rapidly relocate excavators in order to maintain production rates within appropriate quality limits. In addition, the ability to rapidly relocate heavy equipment raises the possibility of improving the quality of repairs by performing maintenance in controlled shop conditions. However, many iron ore operations operate hydraulic excavators in the 600 to 800 t range, with newly released excavator models exceeding 800 t. These excavators are too large to float using conventional technology. This paper examines the potential for using multi-bogie transporters to relocate large hydraulic excavators in surface mines. Recent innovations have seen the development of modular transporters which can be coupled together to achieve larger platform areas. When separated, and with their drive bogies neutralised, these units are able to be towed behind prime movers and relocated between mines via public roads. The potential cost savings for relocating a Terex RH170 excavator in an open pit coal mine are examined. In the first six months of 2008, the analysis showed the potential for a 38 per cent reduction in total travel time with a corresponding revenue increase of approximately $350 k. The paper recommends that a feasibility study be conducted into offering a heavy equipment relocation service within the Pilbara region.

Jan 1, 2009

By Charles C. Boley

Using bench-and pilot-scale coking facilities, the Bureau of Mines produced experimental coke from blends of char with Sunnyside coal (high-volatile A bituminous) from Carbon County, Utah. At bench scale, additions of char made from lignite improved resultant cokes when concentrations of up to 60 pct were used in the blends. At pilot scale (500-pound movable-wall oven), four chars made by entrained-bed carbonization techniques from the parent Sunnyside coal and from a North Dakota lignite were used in two-component blends with the Sunnsyide coal. Chars from Sunnyside coal had volatile matter contents of 5.8, 9.8, and 16.0 pct, moisture-free basis; the char from the lignite had 16.6 pct. In twenty-five 500-pound tests, improvement in coke quality was observed from all blends at char concentrations to 17.5 pct. The best coke, produced from a concentration of 12.5 to 15 pct of S.8-pct volatile char, exhibited physical properties approaching those of an industrial coke produced from Sunnyside coal blended with three higher rank blending coals. Studies were also made of the effects on coke quality of char source, of particle size, of comparative use of char and of a blending coal, and of prolonged coal storage.

Jan 1, 1973