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By N. A. Eilertsen

Procedures of mining high-calcium limestone underground at the Kimballton mine of the Standard Lime and Cement Co. in Giles County, west-central Virginia, are described. Drilling and blasting procedures area discussed in detail, and direct mining costs are tabulated in percentage of total cost. Output, about 1,725 tons of limestone a day, is attained with heavy trackless equipment by the room and pillar method of mining modified by benching floors. Operating features include underground air compression, electric-eye control of curtained doorways, use of a single jumbo drill rig for all drilling, and an effective plan for maintenance of equipment. The company's safety program has contributed to an outstanding safe mining record. The mine is integrated with a plant on the property which converts the stone to metallurgical and chemical grade lime.

Jan 1, 1964

By T. A. Sullivan

The Bureau of Mines investigated modified sulfur concretes as one part of a program for utilizing sulfur in construction materials. The use of modified sulfur was studied as a means of preventing the stressing action in the concretes caused by the allotropic transformation of sulfur on solidification. Unmodified sulfur concretes have been prepared that have compression, flexural, and tensile strengths equivalent or better than Portland concretes. However, most of these concretes have been vulnerable to deterioration by weathering, temperature fluctuations, and freeze-thaw cycling. The sulfur was modified by reaction with dicyclopentadiene or dipentene before use as an aggregate binder. Sulfur concretes and modified sulfur concretes were pre-pared from acidic and basic type aggregates. Physical properties of the optimum mixtures were determined and compared with each other and with Portland cement concretes. The best results were obtained by reacting sulfur with 5 pct dicyclopentadiene to prepare modified sulfur concretes. Field testing of the concretes are in progress. Present results show that modified sulfur concretes are superior to unmodified sulfur concretes and equal or better than Portland concretes in compressive, flexural, and tensile strengths. Long-term aging characteristics of both modified and unmodified sulfur concretes are being determined.

Jan 1, 1976

By G Pattenden, R Hargreaves, P Pettit

"Even with the cyclic nature of mining, when it comes down to it, the bottom line is that whatever direction the commodity market is going there is always a desire to improve the economics of an operation in order to deliver a greater return to investors. Adapting to market pressures by introduction of an operational process change can often have a downstream impact. What may be less obvious is that reconciliation can play an important part in measuring the effectiveness of many operational changes. Through the adoption of best practice reconciliation and related comparisons, it is possible to measure the impact of changes across the mine value chain and identify variability that may have been introduced. Using analytical business improvement tools, examining and monitoring planned changes can be crucial in understanding whether the introduced changes have been effective and whether they have provided the expected result. Using several case studies, the authors will highlight the benefits provided by modern business intelligence tools, which can provide data validation and accurately report data trends related to both planned and unplanned change events.Citation:Hargreaves, R, Pattenden, G and Pettit, P, 2016. Measuring the Effectiveness of Change through Best Practice Reconciliation, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 71–83 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By McMillan W. D.

Vermiculite is the name of a group of micaceous minerals characterized by their property of exfoliating when heated and thereby increasing many times their original volume. The resulting product has excellent heat-and sound-insulating properties, is used as a lightweight aggregate, and has numerous other industrial applications. Deposits of vermiculite occur in areas of pre-Cambrian rocks of the Llano uplift of central Texas, particularly in Burnet and Llano Counties. Because of the growing economic importance of vermiculite products, the Bureau of Mines undertook a detailed investigation of several deposits in Llano County. This investigation was completed in February 1947. The work comprised topographic surveys of five deposits, drilling with a 4-1/4 inch Parmanco power auger drill, and laboratory evaluation of samples. 342 drill holes, aggregating 4,905.5 feet, were completed, and 377 samples were taken. Laboratory evaluation of the vermiculite comprised expansion tests on both crude and beneficiated samples. The products obtained were compared with commercial-grade vermiculite from Montana.

Jan 1, 1949

By K. H. March

In the present very highly competitive condition of the bituminous coal business, it is becoming increasingly apparent that coal mines which do not lend themselves to efficient mechanization cannot long survive. It would seem that those mining operations best fitted to survive the struggle for existence are burdened with the considerable capital and maintenance cast of carefully selected mechanical and electrical mining equipment. The ever changing conditions of coal mine operations require equipment which is adaptable to a variety of uses; and investigation of the mechanical and electrical equipment in most mines will show that the operating duty of much of this equipment is considerably different from that duty for which it was originally selected. And it would appear that one of the essential qualifications for a successful mine management is a marked ability to get satisfactory operating results from equipment which has been transferred from some other operation, rebuilt, rearranged, or in some way adapted to the job at hand. As a striking example of such mechanical ingenuity, many of us recall that the first longwall jigging conveyor used in Nova Scotia was built in Sydney Mines from odds and ends in the scrap pile at a total cost of less than $50.

Jan 1, 1930

By Pragna N. H. Bhakta

The minerals industry is under political and economic pressure to reduce its processing wastes and minimize their impact on the environment: Recycling is one of the means by which the minerals Industry can reduce the quantities of effluents and residues that are discharged to the environment. The wise use of available resources is not only an environmental necessity but also an economic benefit as natural mineral resources are depleted and/or become more complex. The purpose of this paper is to review the technical and regulatory issues that will help shape the future of minerals recycling over the next ten years. Research and development to address technical issues will be discussed with emphasis on the Bureau of Mines recycling research program.

Jan 1, 1992

By Alvaro Diaz

Introduction, who is Teck Red Dog and Quebrada Blanca Mines Uniqueness of environment Arctic versus High Altitude Conditions Logistical challenges People and Stakeholders Conclusions

May 1, 2013

By M. E. Coleman, G. Money

"Clyde Materials Handling is an established customer-driven solutions provider, which utilizes its knowledge, expertise and technologies to transform the production processes of its customers, who operate in the ferrous and non-ferrous metals industries.With over 30 years experience in the process improvement industry, Clyde Materials Handling has helped their global customer base transform the way in which they operate their processes, which has enabled them to generate sustainable economic benefit and maintain their positions as leaders in their respective markets.Clyde Materials Handling has supported operators within the metals market by developing and deploying pneumatic conveying and pneumatic injection technologies. These environmentally supportive and sustainable solutions have been used to transport raw materials within operating facilities, from storage to silo, as well as injecting these materials directly into the heart of production processes.Clyde Materials Handling has worked closely with their customers, such as Codelco in Chile, where their pneumatic solutions have been used to inject a consistent, pulseless and accurate flow of copper concentrate into a bath smelter, which has helped to fuel the operational capacity, availability and productivity.This paper will discuss and highlight the ways in which pneumatic injection technologies, created by Clyde Materials Handling, and applied in partnership with their customers, have helped to improve the operational performance of the production processes of operators across the non-ferrous metals markets with specific reference to applications in the Peirce Smith Converter.Clyde Materials Handling has applications injecting Electronic Scraps, Dusts, Reverts, and other additives to the Peirce Smith Converter. They also have experience of modified PS Units used for Slag Cleaning. There experience with the Codelco Teniente Converter is also directly related to this area of operation."

Jan 1, 2009

By Adam Powell, Salvador Barriga, Matthew Earlam

"The inert anode is a key enabling technology for dramatic energy and emissions reduction in extractive metallurgy. In molten salts, the materials challenge is nearly insurmountable: the anode must conduct electrons at high temperature in a pure oxygen and molten salt environment. A solid electrolyte, e.g. zirconia, between the salt and anode removes the molten salt stability constraint, and can act as a container for a liquid metal anode. This can be liquid silver for oxygen-generating inert anodes, or several metals for natural gas-fueled anodes; it is possible to switch between these modes. The solid electrolyte brings several other benefits: it eliminates molten salt contamination of the anode gas, creates a reducing environment enabling low-cost steel vessels, increases current efficiency, and eliminates carbon contamination of the product. New developments presented here, including current collector and low-cost anode designs, amplify these benefits for producing aluminum, magnesium, rare-earths, and other metals.IntroductionReactive metals such as magnesium, aluminum and rare-earths play increasing roles in efficient transportation and clean energy. In response to new fuel economy standards, automotive OEMs are planning large increases in use of aluminum and magnesium to reduce vehicle weight. Rareearth permanent magnet motors and generators exhibit better power-to-weight and efficiency than induction motors and other designs, making this today's primary motor technology for hybrid and electric vehicles, and for wind turbines. Nickel metal hydride (NiMH) batteries with lanthanum are dominant in hybrids. In 2011, transportation comprised 28.6 out of 103.1 EJ of US energy consumption [1] and 1,845 out of 5,471 million metric tonnes (MMT = 109 kg) CO2e of US greenhouse gas (GHG) emissions [1], creating big targets for economy-wide reductions.Unfortunately processes for making reactive metals for these applications are very inefficient and heavily-polluting. In primary aluminum production, Hall-Heroult cell electricity use [2] is more than double the reaction enthalpy due to heat losses through frozen cryolite side-walls and anode gases, graphite anode plants add significant energy use and GHG emissions [2] (see Table 1). Magnesium is even worse: silicothermic reduction by the Pidgeon process in China produces about 85% of the world's magnesium using coal or coke gas [3]. Chloride electrolysis begins with high-purity MgO and requires carbochlorination or hydrochlorination and costly chloride dehydration [4]—rendered unnecessary for aluminum by the Hall-Heroult cell. Production of neodymium and lanthanum with graphite anodes leads to inconsistent carbon content: small cells make 1 kg batches for analysis, sorting and sale by carbon content, with very high labor and analysis costs. And vertical electrodes give no incentive to reduce anode effect: some reports indicate that China's rare-earth metal industry emits more CF4 and C2F6—with global warming potential (GWP) 6500 and 9200 times CO2 respectively—than China's aluminum industry [5]."

Jan 1, 2014

By L. B. Berger, W. P. Yant, J. B. Littlefield

"INTRODUCTION Hydrogen sulphide (H2S) is one of the most toxic industrial gases and of relatively wide occurrence in industry. Among its common industrial occurrences are, in the production and refining of high-sulphur petroleum, in natural gases, in gypsum and sulphur mining, in rock strata and underground waters (where it is encountered in tunneling and caisson work) in blasting with black powder and in blasting high-sulphide ores with other explosives, in gas manufacture, in the carbonization of coal, and in the manufacture of chemicals.The usual methods of detection, other than by the sense of smell, which is lost in 2 to 15 minutes' exposure to 0.010. to 0.015 percent of this gas, 5/ either are too cumbersome for frequent and rapid analyses or, like the wet lead acetate paper test, afford only qualitative results. A qaantitative determination usually involves the use of solutions, bubblers, flowmeters, standard solutions, burettes, and indicators manipulated by trained technical men. All apparatus and methods in common laboratory use are, in general, unsuitable for the field.The physiological response attending exposure to various Concentrations of hydrogen sulphide in air, is as follows, in percent by volume 6/:0.005 to 0.010: Subacute poisoning - slight symptoms, such as mild conjunctivitis and respiratory-tract irritation after 1-hour exposure."

Jun 1, 1935

By S Bluhm, L van den Berg

In planning mine ventilation systems, heat issues are normally associated with deep-level mines where auto-compression and virgin rock temperatures play a major role. However, a number of mines suffer from high ambient temperatures and humidity, very steep virgin rock temperature gradients and an influx of hot groundwater. Mines in Australia and, particularly, South-East Asia have to deal with these environmental conditions, both in the operational and planning phases. These operations normally have to take heat into consideration during the planning stages at much shallower depths. In high rainfall regions, the water table is saturated and groundwater flow rates are particularly high, which add significant water heat load potential to the mine ventilation system.This paper considers the ventilation challenges associated with hot groundwater conditions in mechanised mines. The paper is based on specific project experience gained from a number of projects in the United States, Australia and South-East Asia and draws on data from mines that experience hot groundwater conditions. For one site, actual decline temperature survey measurements, modelling techniques, management strategies and design considerations are presented.CITATION:Van den Berg, L and Bluhm, S, 2015. Ventilation planning considerations when dealing with hot groundwater, in Proceedings The Australian Mine Ventilation Conference, pp 211–218 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By B. J. Moore

This publication contains routine analyses and related source data for 278 natural gas samples from 14 States. All of the samples were collected during calendar year 1973 as part of a continuous survey of the free world for occurrences of helium in natural gas. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4862 and 576.3 Fifteen previous publications have presented the results of 10,201 gas analyses prior to 1973. The first three, Bulletins 486,4 576,6 and 617,6 contain analyses and related source data on 5,218 gas samples collected from 1917 through 1960. The other 12 publications,7 which were issued as information circulars, supplement the three bulletins and contain 4,983 analyses of samples collected since 1960. This publication is the 13th publication supplementing the three bulletins.

Jan 1, 1974

By John C. Wilmot, Robert E. Brewer, Royce J. Smith

In March 2003, Phelps Dodge started up an innovative pressure leach facility for processing copper concentrates at the Bagdad mine in Arizona. This paper describes the development of the concentrate leaching plant at Bagdad and the operational results from start up to present. Optimization efforts and an approach to mineralogical modeling of the concentrate to calculate oxygen utilization are also presented.

Jan 1, 2004

By G. A. Sutton

"At the San Manuel mine (Arizona, USA), in-situ copper leaching of a copper porphyry deposit was carried out from 1986 to 1999 during underground and open-pit mining. In 1993–1994, well¬field testing of the supergene zone, composed primarily of chrysocolla and copper-rich clay minerals, led to estimates that 52% of the acid-soluble copper (ASCu) could be recovered during in-situ leaching; however, the actual recovery from zone 6, which had the longest leach history, was approximately 42%. Comparing drillcore assay data from holes drilled before and after leaching also indicated an approximate recovery of 42%. The discrepancy between the predicted (52%) and actual (42%) recovery is probably related to several factors, including difficulty maintaining fluid saturation, channelling effects, and gypsum precipitation. ¦ KEYWORDS Copper oxides, in-situ leaching, Modelling, Porphyry, Solvent extraction and electrowinning (SXEW), Well-to-well RÉSUMÉ À la mine San Manuel (Arizona, États-Unis), on a procédé de 1986 à 1999 à la lixiviation in-situ de cuivre d’un gisement porphyre cuprifère pendant l’exploitation minière souterraine et à ciel ouvert. En 1993 et 1994, des essais effectués dans des champs de captage de la zone supergène, composée principalement de chrysocolle et de minéraux argileux cuprifères, ont abouti à des estimations selon lesquelles on peut récupérer 52 % de cuivre soluble dans l’acide (ASCu) pendant la lixiviation in-situ ; toutefois, la récupération réelle dans la zone 6, qui affiche l’histoire la plus ancienne en matière de lixiviation, était d’environ 42 %. La comparaison des données d’analyses de forage obtenues à partir de trous forés avant et après la lixiviation indiquait également une récupération approximative de 42 %. La différence entre la récupération prévue (52 %) et réelle (42 %) réside probablement dans plusieurs facteurs, notamment la difficulté à maintenir la saturation des fluides, les effets de canalisation et la précipitation du gypse. ¦ MOTS CLÉS d’un puits à l’autre, extraction par solvant et extraction électrolytique (SXEW), lixiviation in-situ, modélisation, oxydes de cuivre, porphyreINTRODUCTION in-situ copper leaching at the San Manuel mine, Arizona, USA (Figure 1), began in 1986. It was recognized that some of the copper oxide resource was not economically recoverable by conventional open-pit and heap leach methods using solvent extraction and electrowinning (SXEW) and a high stripping ratio would be required to access part of the resource. At the time, in-situ leaching was becoming popular in the uranium industry, but the approach was virtually unknown in the copper industry, especially at a large scale."

Jan 1, 2019

By Richard A. Thomas, Connor B. Brown, Thomas H. Dubaniewicz, Teresa Barone

Electric vehicles powered by lithium-ion (Li-ion) batteries are being developed by mining vehicle manufacturers as a replacement for diesel-powered vehicles. Explosion-proof (XP) enclosures are frequently employed to enclose electrical ignition sources in gaseous underground mines to prevent the spread of an internal methane-air explosion to a nearby explosive atmosphere. Due to thermal runaway (TR), Li-ion batteries have the potential to cause pressurized explosions in an enclosed structure. Past research has shown the potential for well-confined Li-ion cell TR to drive pressures beyond the conventional pressure specification for XP enclosures. Researchers at the National Institute for Occupational Safety and Health (NIOSH) used an Accelerating Rate Calorimeter (ARC) to induce thermal runaway of Lithium Titanate or Lithium Titanium Oxide (LTO) type 18650 cells enclosed within containers with various volumes and found an inverse power relationship between the TR pressure and available free space. The results were similar in magnitude to that of lithium iron phosphate (LFP) cells, which were used in prior testing. Temperatures, gas amounts, and TR pressure-rise rates were also recorded. The data indicate that with enough free space, the pressures can be lowered below the conventional pressure specification for XP enclosures.

Feb 1, 2024

By HOWARND N. EAVENSON

THE year 1930 resembled the preceding one in the coal industry in continuing the era of falling prices and 'of the abandonment of unprofitable mines. Practically all coal prices fell, and in the steam sizes during the last half of the year this was particularly true, due to the small industrial demand. No new mines of any size were opened in the bituminous coal industry, but there was a steady increase in the number of cleaning plants of all kinds built in all fields. It is estimated that at least nine million tons per year were added to the previous total of washed coal. The largest washing plant started during the year was that of the Buckeye Coal Co., at Nemacolin, Pa., with a capacity of 650 tons per hour. Fig. 1 shows - the mixing-bin, conveyor galleries, washing-plant and skip hoist, and Fig. 2 the 120-ft. Dorr thickener for collecting the 48-mesh material from the wash water. Dryers are used for drying the steam coal product. The following statement by J. R. Campbell shows the effect of cleaning on Pittsburgh coal in Greene County: "With the advent of the 650-t.p.h. efficient washing plant in Greene County at the Nemacolin mine of the Buckeye Coal Co., it has undoubtedly been demonstrated that the potential coking-metallurgical coals of the county can be brought within the pale of the highest grade high-volatile coals for steel manufacture. A few months' operation indicates that 9% per cent ash in the raw coal can be easily reduced to under 7 per cent ash in the washed coal and the sulfur from 1.60 per cent in the run of mine to 1.20 per cent sulfur in the washed coal.

Jan 1, 1931

By Andrew Middleton, Mick Stadter, Chris Crowe, David Chong

"The Level Crossing Removal Project – Package 1 is part of the Victorian Governments commitment to remove 50 of the most dangerous and congested level crossings across Melbourne. This involved removing three crossings on the Frankston Line in the south east suburbs of Melbourne. The works involved replacing approximately 2.5km of at grade track with three rail cuttings up to 8 m deep at each of the bridges that replace the level crossings. The cuttings are retained by piled retaining walls and during the main construction occupation approximately 250,000 cubic metres of soil was removed. The project has presented significant geotechnical challenges due to the location in residential suburbs and tight rail corridor and rail occupation timeframe. These challenges included temporary and permanent wall stability, foundations, earthworks and dewatering. As a result, careful design and innovative construction techniques have been necessary to limit impacts on the community and meet the project timeline.INTRODUCTIONThe Level Crossing Removal Project – Package 1 is part of the Victorian Governments commitment to remove 50 of the most dangerous and congested level crossings across Melbourne. This involved removing three crossings on the Frankston Line where it crosses North Road in Ormond, McKinnon Road in McKinnon and Centre Road in Bentleigh.The project involved replacing approximately 2.5km of at grade track with three rail cuttings up to 8 m deep at each of the bridges that replace the level crossings. The cuttings will accommodate three lines of rail tracks with the cuttings up to 25 m wide. The cuttings are retained by piled retaining walls and during the main construction occupation approximately 250,000 cubic metres of soil has been removed.The project presented significant challenges due to the location in residential suburbs and tight rail corridor and rail occupation timeframe. As a result, careful design and innovative construction techniques have been necessary to limit impacts on the community. The geotechnical challenges generally fell into one of three areas, earthworks, structures and groundwater. The primary earthworks challenge for the project was moving the 250,000 cubic metres of soil in a 10 day window, however, from a geotechnical viewpoint, obtaining a stable subgrade on which to operate the necessary construction plant in a short time frame with constrained site access and time to import materials was the key. Whilst closely watching the performance of the dewatering system, a range of contingency plans were developed to cope with any difficulties."

Jan 1, 1900

By B. Genc, V. J. Mahadeo, S. Ramparsad4, U. Govender

The study was intent on assessing the socio-economic impact of a zinc mine in South Africa through the application of people-centric digital tools using a case study research methodology. The global mining industry is undergoing significant technological shifts to modernize, improve operational sustainability, and align with the environmental, social, and governance (ESG) agenda. While the case study mine is a more modernized mine, continuous improvement around the ‘social’ pillar becomes critical, and to this end application of people-centered digital tools presented as the vehicle to understand community needs and impacts. Despite considerable annual corporate social investment by mines annually, the overall impact or social return on investment is marginally understood. Towards contributing to addressing this gap, digital ESG ‘social-related’ data gathering tools for mines decision-making were developed, including the training-needs assessment tool, community-social needs assessment, small, micro, and medium enterprise (SMME) communications and engagement tool, digital leadership competencies gap assessment tool, and change management blueprint, which further allowed for customization to the mining context. Hence, the novelty of this paper relates to applying digital tools to provide real-time information of the needs of a community, both socially and economically. The findings suggested that these digital tools enabled gathering of information for the establishment of regional and operational baselines towards enabling of social investment returns in relation to socio-economic transformation development interventions. These tools have been applied to a zinc mine context, with lessons and experiences obtained through this study, invaluable to the application of these digital tool in other mines in South Africa. The study was conducted in September 2023 across five host communities, surrounding the zinc mine, in the Northern Cape region, with 120 participants involved in the application of three relevant community-related digital tools, which included the training needs, community-social needs, and SMME communications and engagement tools. It was evident that the digital ESG tools could be used for data gathering for the mine’s informed decision-making and allowed for securing of insights on community needs in near real-time, and further proved practical for community use.

Dec 11, 2024

THE Institute of Metals Division of the A. I. M. E. has joined with the American Society for Steel Treating and the American Welding Society in support of National Metal Week in Philadelphia, Oct. 8 to 12. Individual and joint technical sessions, plant inspection trips, and a general exposition to be held in Commercial Museum have all been arranged. With the coming of the Institute of Metals Division into the circle, the scope of the exposition has been broadened to cover non-ferrous metals, and exhibits of much interest are promised. Headquarters for the Institute of Metals and the American Society for Steel Treating will be at the Benjamin Franklin Hotel, and for the American Welding Society at the Bellevue-Stratford. The American Society for Steel Treating and the Welding Society will hold technical sessions each forenoon at their hotel headquarters. The Institute of Metals Division will hold sessions Tuesday morning and Wednesday and Thursday afternoons; that for Wednesday being a joint session with the American Society for Steel Treating. The latter society will hold independent afternoon sessions on Thursday and Friday. Registration and information desks will be open at the hotels throughout the week, and an attractive program of entertainments has been arranged.

Jan 1, 1928

By Leo Ranney

ANY years ago a prospector came to a Nevada town and built himself a shack. Day after day he searched the hills for gold -but he found none. He closed his shack and hurried north, where a strike had been made. Next he tried to trap the flour gold that floats down the Snake River. He panned the black sands along the Oregon coast. He ranged over the mountains and up the gulches of far-off Alaska. At last, broken in health, six years ago he came back to his old home in Nevada. There his shack still stood-nobody wanted it. One day he started a garden in the rocky soil that he owned. His spade turned up a chunk of quartz, and in that quartz were stringers of gold. He had found a rich gold vein, running right under his own house. You gas producers who have hurried to Oklahoma, Louisiana, East Texas, South Texas, West Texas, even to California to drill wildcat holes a mile or two miles deep-why not, like the old gold prospector, have a look in your own back yard? Some of your coal seams contain 20,000,000 cu. ft. of natural gas per acre.

Jan 1, 1943