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Provide the National Park Service (NPS) with guidelines for closing abandoned mine openings such as shafts and adits. Approach The NPS needed alternative methods of closing a variety of abandoned mine openings on National Park lands. Because the U.S. Bureau of Mines (USBM) has a long history of mining-related experience, the NPS requested that the Bureau provide them with technical mine closure information. USBM engineers compiled information on various types of mine closures and prepared technical illustrations of those closure techniques. Multiple closure options, by type of opening, were prepared as one-page field guides to assist NPS field personnel in determining the most appropriate closure method for a given situation and detailing the construction of the closure method. Results Guidelines provided to the NPS included a description of the method, use applications, construction techniques, technical illustrations, and technical support information. The following provides a brief description of 11 mine closure techniques identified for use by NPS personnel. Most of the closure methods, except the backfill methods, allow for construction that can provide access to the mine. However, providing access makes the closure susceptible to vandalism. Most closure methods require periodic monitoring for subsidence and corrosion or deterioration of construction materials.

Jan 1, 1994

By J. Starwood

Post-super-cycle mining executives must exploit every aspect of the value chain to deliver continued value to stakeholders. Integrating enterprise-wide information technology with value-chain-wide operational technology, known as IT-OT integration, is essential to extracting optimal results from the value chain. Mining companies trail other industries with respect to IT-OT integration across the value chain. Manual data consolidation and value chain optimization using spreadsheets and human intelligence are widespread practices within the industry. Increasing automation with smart devices and controllers means the volume and velocity of data will soon increase beyond human abilities. Enterprise Architecture provides a method for aligning information technology with the business operating model to successfully implement IT-OT integration. A Value Realization Framework (VRF) provides a means for predictable traceable value realization from IT investments and assets. With these principles, frameworks, models, methods, and techniques, mining organizations can accomplish IT-OT integration that provides their executives with a strategic value-chain-aligned platform for sustained value realization over the long term.

Feb 23, 2014

By T. C. Vogt

Earlier we described the uranium mineralogy of an areally broad sampling of Crownpoint ore, including the characterization of organic carbonaceous material associated with the uranium mineral. (1) We also reported on the leaching behavior of Crownpoint ores with a mild alkaline leaching system, oxygen (02)-sodium bicarbonate (NaHC03). (2) There was a wide range of leaching responses, with samples from some areas leaching at a slow rate with low uranium recovery. Evidence indicates that in these samples the organic material is intimately associated with the uranium mineral and shields it to some extent from contact by the leachate. (1,2) One method to obtain faster leach rates and higher recoveries is to use a chemically severe leaching system such as sodium hypochlorite (NaOCI) as an oxidant. (3) The use of sulfuric acid (H2SO4) and an oxidant for leaching ore in surface milling operations is widely practiced to effect high recovery of uranium (U308) from the ore. (4,5,6) The U308 is mobilized as the disulfate complex, U02(S04)224-, or possibly, the trisulfate complex, U02(S04)34-, is the soluble species. (7) Sulfuric acid leachate formulations were used in the first in-situ leaching operation in the Shirley Basin in Wyoming. (8) More recently H2S04 formulations have been used in the Rocky Mountain Energy field tests in the Powder River Basin (Bear Creek) and in the Teapot forma¬tion at Nine Mile Lake site near Casper. (9,10) Laboratory studies related to the use of H2SO4 for in-situ leaching have been reported (11-17) and Yan has .reported packed column leach studies on Crownpoint ore using H2504 and oxidant. (18)

Jan 1, 1981

By Thomas C. Ruhe

The Bureau of Mines conducted research to determine the safe operating conditions for using recycled (used) lubricating oil from mining equipment as a partial replacement for diesel fuel to make ANFO-type blasting agents. The use of recycled oil (RO) saves energy, reduces oil imports, and reduces mining costs. Low ambient temperatures may cause these recycled oils to become too viscous for proper absorption by ammonium nitrate (AN) prills and result in poor blast performance, safety hazards, and environmental problems. To help quantify and resolve these issues, viscosity, mixing, and performance tests were conducted at various temperatures. Diesel fuels No. 1 and No. 2 were studied separately and in blends with 25,50, and 75% RO. Good quality ANFO mixes (94-6) were produced with dry absorbent prills and blended fuel (No. 1 diesel plus RO) at temperatures as low as -40°F (-40°C) with 75% No. 1/25% RO, and at -20°F (-29°C) with 50/50. Diesel fuel No. 2 also made good mixes as low as -30" F (-34°C) with 75% No. 2/25% RO, and at 0°F (-18°C) with 50/50.

Jan 1, 2008

By Harry C. Gatos, Frank J. Bachner, Mario D. Banus

The portion of the Nb-Sn phase diagram between 75 and 79 at. pct Nb at temperatures near the liquidus has been investigated by melting alloys of known composition and examining the microstmc-tzlres resulting when these melts were quenched. The Nb-Sn samples were contained in magnesia sleeves, and were mounted in a high-pressure apparatus. It was shown that Nb3Sn me1ts by a peri-tectic decomposition and that the composition of the compound Nb3Sn at the peritectic horizontal lies between 77 and 78 at. pct Nb. Analysis of the phases present in the samples was accomplished by anodic staining techniques and an electron-microbeam analyzer. DURING the past several years a great deal of work has been devoted to the Nb-Sn system, and the bulk of this work has been primarily concerned with the intermetallic phase Nb3Sn. However, the melting characteristics of Nb3Sn have not been investigated because of the difficulty in maintaining known compositions due to tin losses by vaporization, and the added difficulty of containing Nb-Sn alloys without sample-container reaction at the high temperatures involved. This paper reports on the development of a technique for containing Nb-Sn alloys under pressure high enough to prevent tin losses at temperatures in excess of the liquidus. Using this technique, melts of known composition were made and a phase diagram near the liquidus is proposed based on the microstructures resulting when these melts were quenched. EXPERIMENTAL The Nb-Sn alloys weighing 0.7 g each were prepared in the form of cylinders. Niobium powder, -200, +325 mesh, and tin shavings with a minute amount of tin powder for a binder were mixed in the desired proportions and cold-pressed at 50,000 psi in a 0.150-in. die. This cylinder was then enclosed as shown in Fig. 1, and the entire arrangement mounted in a 2.6-in. pyrophyllite tetrahedron.' The desired temperatures (-2500°C) presented several problems in high-pressure container materials. Boron nitride, the usual sample holder, was found to react with niobium to form the nitride. However, MgO cans and plugs machined from refractory rods did not melt nor react with the sample. Thick tantalum contact disks were used to carry the large currents (~450 amps) to the graphite heater, since tantalum did not melt and had enough strength to prevent extrusion of the sample. It was further observed that the graphite heater and tantalum disks could not be in direct contact with the pyrophyllite because it melts and decomposes at these temperatures to kyanite and coesite (SiO2),2 the former reacting with graphite and the latter with tantalum to form the silicide. The use of a MgO outer sleeve

Jan 1, 1965

By Paul Torrey

IN his recent article, Stanley C. Herold described some of the principles involved in oil-field rejuvenation. The purpose of this paper is to present certain facts, based upon observations of systematic water flooding of oil sands in the Bradford and Allegany fields of northwestern Pennsylvania and southwestern New York, which, it is believed, will partially substantiate Mr. Herold's opinions. The writer gratefully acknowledges his obligation to the Forest Oil Corpn., the Kendall Refining Co., the Petroleum Reclamation Co., W. J. Healey, of Bradford, Pa., and the Producers Oil Corpn., of Olean, N. Y., for information included in this article; and he is especially indebted to Jerry B. Newby, of the Petroleum Reclamation Co., for helpful suggestions and criticism in the preparation of the paper. It is obvious that, in the calculation of mathematical formulas for the prediction of oil recovery, uniform conditions must be assumed; otherwise, the applicability of the results of such work will be, by necessity, restricted to the area or individual property for which they were designed. Geologic and physical conditions are so variable throughout the fields where water flooding is practiced that it is difficult to devise methods that can be universally applicable. However, it is believed that there are certain fundamental principles which, when applied with specific modifications designed to meet the conditions existing in local areas or individual properties, may yield considerably greater recoveries of oil.

Jan 1, 1927

By F. P. Haver

The Federal Bureau of Mines investigated aqueous electrolysis as a means for reducing lead chloride prepared by ferric chloride leaching of galena concentrate: NaC1 PbS + 2FeC13 ? PbC12 + 2FeC12 + S°. During electrolysis, metal was produced from solid lead chloride in contact with the cathode rather than from lead in solution. Relatively high current densities--up to 300 amp/ft2--were possible when operating in this way. A very simple cell, having a horizontal lead cathode at the bottom and a vertical graphite anode at the top, was employed. Lead chloride crystals, covering the cathode, were converted to metal powder during electrolysis, and chlorine gas or FeCls was produced at the anode, depending on the electrolyte composition. Electrolytes tried included aqueous solutions of HCI, NaCl, NH4Cl, and FeC12-NaC1. Optimum results (96-pct current efficiency, 0.23 kwhr/lb Pb) were obtained with 20 pct HC1 at 25° C, using a current density of 15 amp/ft2 and an electrode spacing of 1 inch. When the current density was increased, the energy requirement increased also but only to 0.41 kwhr/lb at 150 amp/fr3 and 0.58 kwhr/lb at 300 amp/ft2.

Jan 1, 1978

By L Cain, C Every, S Mirlatifi, J Ashley

This paper presents a geographic information system (GIS) based method for the prediction of ground movement and the associated impact on existing buildings and structures due to tunnelling in the North West Rail Link (NWRL) project. The NWRL is a priority rail infrastructure project for the New South Wales (NSW) Government and includes 15 km of twin tunnels between Bella Vista and Epping, which will be Australia’s longest rail tunnels. The NWRL tunnels will be constructed in an urban environment where the prediction of ground movements induced by tunnelling and the associated impacts to existing structures must be assessed in the early design stages of the project. An assessment process was developed using GIS able to respond to design changes.An iterative GIS analysis methodology was developed to generate ground settlement contours and identify impacted buildings and structures in response to multiple changes in tunnel alignment during design development stages. The GIS analysis undertook to rapidly provide detailed and accurate parameter information including tunnel depth from surface, tunnel separation, diameter and sample point proximity to the tunnel and assess ground movement contours along the project alignment. Determination of the ground surface settlements were based on empirical methods proposed by Peck (1969) and Mair (1993). The control parameters and the relationship between damage categories and risk classifications for impact assessment were based on Burland, Broms and de Mello (1977), Rankin (1988) and Boscardin and Cording (1989) methods.The GIS-based ground movement impact assessment approach adopted for the NWRL project demonstrates an efficient, iterative and robust approach and could provide an initial framework for other similar tunnelling projects where rapid design changes and early understanding of tunnelling impacts are required to bring greatest benefit to all stakeholders.CITATION:Mirlatifi, S, Cain, L, Ashley, J and Every, C, 2014. An iterative geographic information system based approach for the assessment of tunnelling impact to existing buildings and structures, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 647–652 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

Provide a low-maintenance, reliable means of generating bubbles and controlling bubble size for column flotation. Approach Commercial sparger systems used in flotation columns to process minerals provide only limited means of controlling the size of bubbles generated and the rate of air injection. Generally, these limitations are a detriment to flotation performance, particularly in recovering coarse or fine mineral particles. In addition, conventional bubble generation systems require frequent maintenance, often requiring shut-down of the column itself for repairs. To permit greater control of the bubble size generated in the flotation column and to eliminate the counter-productive problems associated with the operation of current air sparger systems, the Bureau of Mines investigated alternative methods for generating bubbles. Based on the investigation, an external bubble generation system was designed, developed, and laboratory and commercially tested.

Jan 1, 1987

[Executive E. DEGOLYER, Chairman SYDNEY H. BALL WILLIAM H. Bassett RICHARD PETERS, JR. J. V. W. REYNDERS Finance GEORGE D. BARRON, Chairman H. A. GUESS GEORGE OTIS SMITH]

Jan 1, 1928

By D. L. Hollis

An arc plasma reactor, constructed and used for studying extractive metallurgical processing, was adapted by the U.S. Bureau of Mines to separate gases of different masses by using the high rate of plasma rotation. With argon and helium as input gases, peripheral reactor outlet ports had a measured average increase of about 10 pet in argon concentration relative to helium with the plasma on compared with plasma off for the same gas inlet concentrations in both cases. Approximately the same average increase in argon concentration occurred from the peripheral outlet port compared with a central outlet probe with the plasma on. There was no difference with the plasma off.

Jan 1, 2010

By Rudolf E. Greuer, Linneas W. Laage, Xinton Chang

UNIT OF MEASURE ABBREVIATIONS USED IN MFIRE FT foot FT3/MIN cubic foot per minute LBM•MIN2/FT4 pound mass times minutes squared over feet to the fourth FT2/HR square feet per hour BTU/HR*FT*F British thermal unit divided by hours times fimes feet times degree Fahrenheit IN W G inches water gage FT3/MIN cubic feet per minute FT2 square feet FT3 cubic feet LBM, pound mass F Fahrenheit IN W G /CFM2 inches water gage per cubic foot per minute squared PERCENTAGE percent BTU/MIN British thermal unit per minute MFIRE BAT PROGRAM cls echo off echo MFIRE activated mfire0 echo Wait a moment for loading the program if EXIST zheng chg mfirel if EXIST zheng chg mfire2 if EXIST zheng chg mfire1 if EXIST zheng chg erase zheng chg if EXIST hang chg erase hang chg if EXIST yunzhi fan copy yaodong.ion+yunzhi fan yaodong ion if EXIST yunzhi fan erase yunzhi fan if EXIST xintan chg copy yaodong xin+xintan chg yaodong ion if EXIST xintan chg erase xintan chg if EXIST yaodong xin copy yaodong.xin mfire out if EXIST yaodong.xin erase yaodong.xin if EXIST net erase net echo Your output is saved in file MFIRE OUT MFIRE0 FOR PROGRAM CHARACTER•50 A OPEN (10,FILE='NET',STATUS='UNKNOWN',FORM='UNFORMATTED') NETWW=0 WRITE (10) NETWW OPEN (21,FILE='ZHENG CHG',STATUS='UNKNOWN',FORM='UNFORMATTED') A=) ' B=0.0 WRITE (21) A WRITE (21) A,B

Jan 1, 1990

By Roberta L. Hudak, Ellsworth R. Spencer, Eric R. Bauer, Adam K. Smith

The National Institute for Occupational Safety and Health (NIOSH) is conducting research with the objective of preventing hearing loss in the mining industry. Longwall mining is one sector that has received considerable attention. Studies involving the monitoring of worker noise exposures, characterizing equipment sound levels and dominant noise sources, evaluating engineering noise controls, analyzing hearing protection device (HPD) effectiveness, and testing of improved sound level monitoring techniques specifically for longwall mining systems, are being conducted. The research efforts revealed that stageloader operators are the most exposed longwall workers, with the discharge end being the noisiest location along the stageloader. In addition, the studies have shown that using stationary dosimeters, coupled with observational data of the cutting cycle and worker habits, has the potential for improved monitoring of the effectiveness of engineering noise controls. To address the ineffective use of soft foam earplugs, a simplified 3-step method was developed for inserting soft foam earplugs. Results indicate a 9 dB greater attenuation after training subjects on the 3-step method. Finally, muff type HPDs are being evaluated for effects of speech intelligibility in noise. The combined results of these studies illustrates that much can and has been done to prevent noise-induced hearing loss (NIHL) in the mining industry, especially with respect to longwall mining workers. This paper presents an overview of ongoing studies, a progress report of results, and the implications for reducing worker noise exposures and preventing NIHL in longwall mining workers.

By Barrick Pierina, John Frostiak, Igor Gonzales, Kenneth G. Thomas, Ken Manning

"1.0 SummaryThe Pierina deposit was acquired in August 1996 when Barrick Gold Corporation purchased Arequipa Resources, a junior mining company with extensive land positions in Peru. At the time of acquisition, Arequipa had developed two exploration tunnels and drilled 9 exploration holes on the property. Metallurgical tests, conducted on samples taken from the tunnels and the exploration holes indicated that the ore was amenable to heap leaching. Barrick’s exploration team recognised from the outset, the potential of the mineralisation and convinced Barrick’s senior management that this was indeed a world class deposit that should be pursued. On November 25, 1998, the first dore was poured at Pierina, 27 months from the time of acquisition. During that period Barrick completed its exploration programme, prepared a development plan including capital and operating costs, production profiles and cash flow forecasts, and a schedule to develop a mine and construct a leach pad and gold recovery plant, including all supporting infrastructure. All permits and environmental approvals were obtained and all necessary land was acquired. The project was completed on schedule and under budget. This was the first greenfield mine development for Barrick outside of North America.This paper details, mainly, the research and development, engineering, construction and commissioning of the metallurgical process facilities.2.0 The Develonment ProgrammeImmediately after the acquisition, Barrick began the process of gathering information required to prepare a project development plan. Kilborn Engineering was retained to assemble all of the information collected and collated into a development plan document. This document was completed by June 16,1997. The objective was to bring the mine into production as quickly as possible with critical activities identified as follows:"

Jan 1, 2000

In the last five years, new iron ore pellet plants have been built with significantly reduced air pollution levels compared to the older generation of plants. European and American pollution controls are more stringent that in China and Brazil. The recent American plants have successfully employed circulating fluidized beds for sulfur control, baghouses for particulate control, activated carbon injection for mercury and a new design of specialized low-NOx burners.

Jan 1, 2015

An examination has been made of the rate and extent of removal of carbon from scrap metal charges when the melt is exposed to atmospheres which are reducing or oxidising with respect to FeO at unit activity. The mechanisms of decarburisation of molten Fe-C-S- P-Mn-Si alloys with H2/CO/H20/C02 gas mixtures with controlled compositions at high or low concentrations of carbon in the melt in the presence and in the absence of sponge iron, in both slag free melts and in the presence of various slag forming additives are discussed. A significant quantity of carbon can be removed from the metal during the melting stage and under optimum conditions, a high percentage of metal recovery and low carbon can be obtained after exposure of melt to the above gas mixture with controlled compositions. The presence of ferrous oxide provided by poorly reduced ore in the charge and the use of controlled atmospheres facilitated the removal of carbon to very low level during the melting period.

Jan 1, 1984

TWO American students entered the École des Mines in 1856, Joseph Lesley of Philadelphia and Thomas Egleston of New York. Lesley remained there only one year, but Egleston completed the whole curriculum and received, in 1860, the certificate given to foreign students in lieu of the official appointment and degree awarded French students. Returning home he received, in 1861, an appointment by Secretary Henry of the Smithsonian Institution to sort, label, and arrange the collections of mineralogical and geological specimens which had been brought to Washington by the various government exploring expeditions in the West. Thomas Egleston, born in New York City on Dec. 9, 1832, was the son of Thomas Jefferson Egleston, who came to New York from Massachusetts some time before 1829. The first American ancestor of the family had settled near Dorchester in 1630. T. J. Egleston and Joseph Battell established an iron-merchandizing business* at 166 South St., New York, which prospered exceedingly; so much so that when Thomas J. Egleston died, July. 12, 1861, his estate had a book value of over $500,000. Since an older brother was expected eventually to take over this business, Thomas, who had a liking for science, went to Yale, where he completed the regular four-year course in 1854, and then remained another year for advanced work in chemistry under Silliman. One biographer says he went to Europe, early in 1856, on account of his health. It was the custom at that time for wealthy young men to make a tour of Europe after completing their academic education. Whatever the precise reason, he began scientific work at the Jardin des Plantes in Paris but soon trans-

Jan 1, 1941

By Rory Cameron, Chuck Edwards

"Stringent environmental performance criteria and regulations, and the desire to minimize water use have made membrane-based treatment and separation processes an attractive option. This has lead to many advances in all aspects of the technology. Membrane separation processes have found application in sea water desalination, brackish water treatment, decontamination of ground water, and wastewater treatment. Development of membranes with better resistance to harsh feed conditions has created new opportunities for the broader application of membrane separation technologies to mineral processing streams. There are examples in mineral processing operations, including treatment of acidic drainage, pre-concentration of pregnant leaching solution in heap leaching operations, separation of acids and metals from waste streams and intermediate process streams, as well as gold and cyanide recovery from a heap leaching operation. This paper provides a brief overview of membrane technology principles, followed by a discussion of current membrane technology applications relevant to the mining and mineral processing industry. The paper further explores the potential for the application of membrane separation as an integrated component in mineral processing operations.INTRODUCTION Increased regulatory pressures, emphasis on water conservation, and scarcity of water in arid regions have resulted in substantial changes in industrial practices in recent years. As a result, many industries have become more open to adopting innovative technologies such as membrane separation. The mining industry, which is typically very conservative, has adopted membrane separation as an effective end-of-pipe solution for effluent and acidic drainage (AD) treatment; however, its use as an integrated component in plant operations has progressed more slowly. With increasingly stringent environmental regulations coupled with the desire for low- and zero-discharge operations, the use of membrane separation technology for achieving acceptable environmental performance may be unavoidable in the future. The relatively small footprint requirement, versatility, and modular construction of membrane separation units facilitate their introduction into existing processes with a suitable feed stream. Membrane separation is not a stand-alone process that provides the ultimate solution to water and wastewater treatment; however, it can often be economically added to conventional waste treatment plants to increase throughput and/or decrease contaminant output (Mortazavi, 2008). Although membrane separation technology has become an established separation technique that is widely used in drinking water production and other industries, it is still considered an emerging technology within the mining and mineral processing industry. This technology offers many potential benefits such as clean water recovery from wastewater, significant reduction of volume requiring conventional treatment, decreased usage of reagents, and acid recovery, all of which lead to increased treatment efficiencies and lower reagent consumption. This could translate to smaller and more efficient plants with lower capital and operating costs and lower environmental impacts. Plant expansion may be facilitated by incorporating a membrane separation unit operation in order to utilize existing treatment systems at higher throughputs."

Jan 1, 2012

By Arthur M. Hartstein

The Federal Bureau of Mines, under a contract with Ultrasystems, Inc., investigated the thermal oxidative degradation characteristics of conveyor belts used in underground mines. This included the determination of smoke evolution, glow characteristics, char yields, and the identification and quantification of all volatile decomposition products in the form of gram of specific product formed per gram of belt sample tested. In addition to these investigations, degradation studies were conducted on some pure ingredients used in conveyor-belt formulations. Three basic classes of belts were investigated: neoprene, polyvinyl chloride, and styrene-butadiene rubber compositions. The studies indicate that styrene-butadiene-based belts exhibit good flame resistance and are the least hazardous in regard to overall formation of toxic decomposition products. Under this program, thermogravimetric analysis was definitely established as a method of material differentiation.

Jan 1, 1976

By Joseph S. Young

During 1975, the Reclasource Corp. constructed and started up a plant for the recovery of mill scale, coke breeze, blast furnace dust; blast furnace sludge; and TOC dust, at the site of Crucible Steel, Inc., Midland, Pa. The Reclaform Process was employed as the criteria for plant design. This process takes the solid wastes (as listed above) which are commonly found in integrated steel mills, sizes them, forms them through the use of a carbonaceous binder briquetting system, and fixes the binder through a final heat treating step. Blast furnace tests have been performed on 15,000 tons of Reclaform briquets. This paper gives a brief history of the program, and describes the process and the raw materials involved. The blast furnace campaign and its major conclusions are discussed.

Jan 1, 1977