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By H. P. Greenwald

Cooperation between the Bureau of Mines of the United States Department of the Interior and the Safety in Mines Research Board of Great Britain dates from 1924. It has been intimate and has involved exchange of personnel and. equipment as well as information. Correlation of divergent results obtained in large-scale tests of the explosibility3/ of coal dusts made in the respective countries was one of the first problems to be studied. The purpose of this paper is to show to what extent such correlation has been achieved. COMPARISON OF TEST METHODS The first research accomplished Jointly by the two organizations was a comparison of large-scale methods of determining the explosibility of coal dust. Large samples of coal were exchanged and subjected to test in the Bureau's Experimental coal mine and in the Board's steel gallery, 38 inches

Jan 1, 1939

By T. L. Johnston

The Dobbins property, about 4-1/2 miles northeast of Cartersville, Ga., was fist operated in 1866, it is the oldest manganese mine in Georgia and one of the oldest minus in the United States still producing manganese ore. Changes in ownership, lessees, and operators and lack of records prevent the compiling of statistics regarding total production of ore from the property.

Jan 1, 1942

By T. L. Johnston

The Dobbins property about 4-1/2 miles northeast of Cartersville, Ga., was first operated in 1866. It is the oldest manganese mine in Georgia and one of the oldest mines in the United States still producing manganese ore. Changes in ownership lessees and operators and lack of records prevent the compiling of statistics regarding total production of ore from the property

Jan 1, 1942

By Victor E. Kral

The Valery fluorspar deposit , also known as the Hamilton deposit , is northeast of Lovelock and 4 miles by poor dirt road east of U. S. Highway 40 . It is in the Humboldt Mining District , on the west side of the Humboldt Range , at an altitude of 6,000 to 6,500 feet . The property was examined by the Bureau of Mines on February 83/ and April 8 , 1944.4/ The last examination was made with an engineer of the Geological Survey.5/ Exploring by means of trenches , cuts , shaft sinking , coyote holes off the shaft , and a small amount of prospecting with short drill holes , was begun in January 1945 and was completed June 30 , 1945. An engineer6/ of the Geological Survey visited the property in April and again in June 1945 to complete a topographic map of the area and to note the results of exploration by the Bureau of Mines . Only minor surface exploring had been done on fluorspar occurrences previous to the Bureau's work . No mining equipment or living facilities are on the property .

Feb 1, 1947

By Daniel Ng

The U.S. Bureau of Mines-Michigan Technological University mine ventilation mainframe program was successfully adapted for execution in a personal computer (PC). The hardware requirement can be as modest as 256 kilobytes (33) of random access memory (RM) and two floppy disk drives. A version compiled for a PC possessing 512 Kb RAM has arrays dimensioned to accommodate 512 separate mine airways and junctions, and it contains all the features and capabilities of the original version. It has successfully analyzed all the ventilation networks tested, including a very large commercial mine (404 airways, 237 junctions, and 5 fans). In all cases the PC version produced practically identical results as obtained from the mainframe computer. In all respects, the PC version performed the same as the mainframe version with the exception of execution speed When a numerical coprocessor is employed, execution time can be reduced by more than 50%.

Jan 1, 1989

By W. E. Robinson

Differences in the composition or chemical structure of the organic material in samples of Uinta Basin (Utah) oil shale were studied relative to stratigraphic position within the Green River Formation. This involved a systematic study of the soluble organic material and the insoluble organic material (kerogen) present in the samples. Emphasis was placed upon the distribution of the alkanes (normal and isoprenoid compounds) in the soluble extracts and upon the aromaticity of the kerogen. Significant differences exist in the chemical composition of the organic material from various strata within the Uinta Basin, some of which were related to burial depth but most were related to source material variations, environmental differences, or other factors. The Uinta Basin samples differed significantly from Piceance Creek Basin and Green River Basin samples in the large amount of soluble extract they contained.

Jan 1, 1975

By Richard D. Begley

This paper will present the results of an analysis of several abandoned coal mine projects and includes field data for over a dozen different reclamation projects recently completed in the state of West . Virginia. The analysis was performed with the objective of summarizing and or classification of the environmental consequences with reference to the characteristics of the mining facilities (surface, underground, etc.). The analysis also addressed the itemized cost of remediation with respect to procedures, environmental concerns and time. The results of the analysis are that each abandoned coal mine site in West Virginia have/had many unique features and in most cases include a combination of environmental concerns that complicate comparisons. The study also revealed that the abandoned mine land program for mines abandoned prior to 1977 that is being financed by a tax on the production of coal, has produced many benefits for the state of West Virginia. This grant program administered by the Office of Surface Mining, has resulted in a high quality methodology of remediation that has been successful for many years in greatly minimizing and/or eliminating environmental concerns from abandoned coal mines.

Jan 1, 1997

By Tyler Blake

This report describes a study designed to evaluate a pro-posed modification in the cap lamp battery cord intented to reduce the incidence of snagging and catching of the cord. A three phase evaluation was performed comparing a prototype with the standard, currently available cord. First, a ?pull test? equipment was run. The second evaluation was a body conformity study. The third evaluation involved subjects performing common tasks in a low seam coal mine simulator. The results of these evaluations clearly demonstrated significant safety advantages of incorporating coiled cord into the design of the cap cord. The coil cord presented less of a snagging hazard, allowed the wearer more time to respond to a snag, and transmitted lower levels of force to the helmet when snagged. The research team recommended that cap lamp cords be commercially developed which incorporate coiled cord at the battery and helmet.

Jan 1, 1980

By S. R. Knowles, R. J. McDonough

"The purpose of this paper is to introduce to the minerals processing marketplace a viable alternative to conventional mechanical agitation and pachuca airlift agitation. What follows is a brief introduction to the Atara Corporation and the fundamentals of how an Atara ""cannon"" mixer operates. The main body of the paper is concerned with the results of a study to evaluate the cannon mixer for a gold cvanide leach application. A brief summary of research and testing for other metallurgical applications is also presented.1. 1 THE COMPANYThe Atara Corporation is a privately owned Canadian company, headquarted in Dorval, Quebec. Its subsidiary, Atara Incorporated, located in Paramus, New Jersey services the municipal wastewater treatment market in the United States. Dorval focuses on industrial mixing applications in Canada and the US. The Atara Corporation provides design, engineering and specifications of agitators for mineral land other) processing applications. Fabrication of mixers is pursued in either Canada or the US, depending on the ultimate destination.Although Atara and its unique static in-tank mixer are relative newcomers to the mining industry, the cannon mixer has demonstrated its value over the past 20 years in municipal wastewater treatment services. In the past four years the Atara unit has been developed for industrial applications; the bulk of the development work has been for metallurgical applications. To-date the cannon mixer has been evaluated for mixing slurries in the following applications: nickel-copper concentrate storage, copper concentrate storage, coal slurry storage, gold cyanide leaching, uranium acid leaching, silver leaching and zinc acid leaching. Atara mixers have been installed with successful performance in full scale tanks containing nickel-copper concentrate slurry (Falconbridge) and gold cyanide leach pulp (Dome"

Jan 1, 1984

By M Jacobs

This abstract discusses a heap leach copper mine that was failing to perform and as a result was not meeting targeted production. The mine had numerous technical challenges including: high water inflows, low levels of geotechnical monitoring, performance issues with mining, resource model and grade control reconciliation issues, and unexplained low levels of performance from the heap leaching operations. A team from various organisations with specialist skill sets including: a forensic accountant, the owner’s representative and a mining engineer, was arranged to visit the site. The task was to investigate the situation and determine what could be done to turn the performance of the mine around. After an initial assessment in late 2018, efforts were directed to better understanding the operations and improving the performance of the site through preventative management. A key part included the creation of production forecasts that could be achieved that would help restore confidence in the operations. Uncertainty in the mine achieving production forecasts and the performance of the heap leaching operations were contributing to the decline of the operations. Investigations uncovered the fact that while the resource model could reliably predict total copper, a lack of sequential leach data meant the accurate prediction of soluble and insoluble copper species, both important for heap leaching, was difficult to do with any degree of certainty. The crushing and mining contractors also appeared to have suffered somewhat from a lack of management by the owner’s team and performance had affected the production of copper. Collaboration and management were used by the team to understand and stabilise the operations. Ongoing collaborative efforts by the management team, site personnel and contractors resulted in a positive outcome for the owners and their mine – and could at yours.

Jun 22, 2022

By N. S. Kim

Economically favored Cr and Cu leaching out process from spent power plant fly ash (PPFA) had been investigated. PPFA, bearing of C, S, V, Ni, Cu and Cr, has been widely used as an assistant fuel in cement industry. Recent environmental regulation in S. Korea prohibits using PPFA as a fuel. Many researchers have also studied on extraction V and Ni from PPFA. Due to low concentration of V and Ni, 2% and 1%, respectively, economical and environmental friendly process could not be found. In this study, Cu and Cr have been removed in an economical way and which satisfied with KS Extraction Test. The rest unburned carbon, V2O5 and NiO2 in residue were found to be applicable for indoor and outdoor colored bricks or deodorant panel. Various parameters such as pH, lixiviates and time on leaching behavior were investigated in order to leach Cr and Cu remaining C, V and Ni. Keywords: Fly ash; Selective extraction; Ammonia; Deodorant panel

Jan 1, 2009

Within CRLÆs lifetime there have been a number of products that have proceeded through their life cycles. In each case market forces and technological advances have forced the cessation of the product. The company has then had to develop alternative outlets for its copper. Sometimes it has produced a similar product to fill the same market. In other cases the extra copper is sold as cathode. Today, CRL produces no semi-fabricated copper products and all cathode is sold. More recently, CRL has ventured into the sale of technology and manufacture of cathode motherplates. This area, whilst it is not what had been a traditional area of core business, has been found to be profitable.

Jan 1, 1998

By R. Kuyvenhoven, A. Parbhakar-Fox, X. Prieto, J. Quevedo, L. V. Danyushevsky

This paper presents the results of a study focussed on determining the distribution of cobalt in different types of pyrite of the La Estrella IOCG deposit in Chile. In the IOCG mineral deposits, where copper is the main product, the quantification and distribution of cobalt is required to correctly define the technical and economic viability of recovering cobalt as a by-product. In the La Estrella mineral deposit, seven alteration and mineralisation events were recognised through both optical and automated electronic mineralogical analysis. Of these seven events, five different types of pyrites were identified, each with unique characteristics of the pyrite crystals. Through advanced elemental analysis of these five types of pyrites, it was determined that the concentration and distribution of cobalt within the pyrite crystal is dependent on the mineralisation event. The results indicate high cobalt concentrations in the early pyrite mineralisation events, associated with relatively fine pyrite grains, and cobalt generally occurring in a solid form in the pyrite core. The late pyrite mineralisation event exhibits the lowest concentrations of cobalt, with cobalt predominantly present along the outer periphery of the pyrite. These results are relevant from a metallurgical point of view because the preferential location of cobalt within the pyrite crystal will influence the maximum metallurgical recovery of cobalt. For this, a cobaltiferous pyrite concentrate must be formed which, according to the characteristics of pyrite, must be processed with the optimal solubilisation method. The overall objective is to ensure both good cobalt recovery and a high concentration of cobalt in the leach solution resulting from pyrite leaching. Keywords: Cobalt, pyrite, IOCG, copper, metallurgical recovery, solubilisation, Chile

Jan 1, 2020

By B. K. Cantrell, K. L. Rubow

"The US Bureau of Mines and the University of Minnesota have developed design and performance criteria for a personal diesel exhaust aerosol sampler for underground coal mines. These are based on the premise that size can be used to separate diesel exhaust aerosol, which is mostly submicron in size, from coal dust aerosol, which is mostly greater than a micron in size. The sampler has three stages: a respirable aerosol preclassifier, a 0.8-um aerodynamic diameter inertial impactor to collect mineral dust and a final filter to collect the diesel aerosol. Using a sample flow rate of 2 L/min and gravimetric analysis to within 0.1 mg, the measure sub-0.8 um diesel aerosol has an a-priori limit of detection of 0.3 mg/m3.A miner working in an underground coal mine with diesel equipment is exposed to a wide array of pollutants from the diesel exhaust. These include CO, CO2. NO, NO2, SO2, diesel exhaust aerosol, and a variety of hydrocarbon compounds. A quantitative definition of the health risk resulting from these exposures remains elusive. During the past several years, though, progress has been made in defining the problem.Results from epidemiological studies by Garshick et al. (1988 ), animal inhalation studies by Mauderly eta). (1986), Iwai et al. (1986), and Brightwell et al. (1986) and in vitro studies by Lewtas et al. (1986) have provided sufficient data for the National Institute of Occupational Safety and Health (NOSH) to recommend that ""whole diesel exhaust be regarded as a 'potential occupational carcinogen,' as defined in the Cancer Policy of the Occupational Safety and Health Administration"" (NIOSH, 1988). NIOSH further stated that ""though the excess risk of cancer in diesel-exhaust-exposed workers has not been quantitatively estimated, it is logical to assume that reduction in exposure to diesel exhaust in the workplace would reduce the excess risk.""The Mine Safety and Health Administration (MSHA) has also been directed by an advisory committee to establish a diesel exhaust aerosol standard and to establish regulations to minimize exposure to diesel pollutants in underground coal mines (MSHA,1988). Both reports point out the need for development of measurement techniques for respirable diesel aerosol.In the past four years, the US Bureau of Mines (Cantrell,1987 and Cantrell, et al. 1987), in cooperation with Marple, et al. (1986), at the University of Minnesota's Particle TechnologyLaboratory (PTL), have studied the use of size-selective sampling techniques to measure the mass concentration of diesel aerosol in underground coal mines. Results from these studies have been used to develop design and performance criteria for a personal diesel exhaust aerosol sampler for use in underground coal mines.These criteria are based on the premise that size-selectivesampling techniques,can be used to separate diesel exhaust aerosol, which is predominantly submicron in size, from coal dust aerosol, which is mostly greater than a micron in size. In addition to the performance criteria, this paper discusses the laboratory and field test data used to develop the criteria."

Mar 1, 1992

By A. G. Galaitsis

This report summarizes the work performed under the USBM Contract No. J0245001. The purpose of this work was to expand and improve the scope and accuracy of the method developed under USBM Contract No. J0113056 for the prediction of the number of overexposed workers in the mining industry. A significant portion of the noise data were acquired during mine visits-that took place in the-course of this contract. These data were obtained with time-resolved dosimeters which among other things store a time history of the sampled noise for an eight hour work period. The remainder of the noise data have been obtained from MSHA files and from other BoM-sponsored projects. The report reviews the prediction model, discusses the model's assumptions and approximations, describes the function of the developed software, offers typical examples on the use of the software and includes plots of the newly acquired noise data records.

Jan 1, 1986

By David A. Summers

Coal is increasingly viewed as one of the major fuel resources of this country for the remainder of this century. The need to extract a greater percentage of the coal in a given seam, together with advantages of improved safety, indicates that longwall mining will become more widely used within this time frame. A novel method of mining coal on a longwall face, utilizing high pressure water jets, is herein described. The mining machine proposed will exploit the stress conditions which exist on a longwall panel in order to achieve the required productivity while at the same time reducing respirable dust and methane ignition hazards. The water jets will excavate only the boundary of the extracted seam section, and thus the energy requirement of the machine will be minimized. The action of the machine is similar to that of an existing coal plow, except in that the wedge teeth of the plow are replaced by oscillating high pressure water jets. The machine can, therefore, cut to the depth and at the speed of existing shearer units at equivalent power levels. The removal of impact stresses from the machine will reduce downtime required for maintenance and replacement of picks and lower the load on the haulage motor of the system. The ability of the machine to increase the depth of cut without an increase in horsepower will further improve productivity when transportation systems to remove the greater production are in operation.

Jan 1, 1974

By Robert Roby

The Mouat copper-nickel deposit in Stillwater County, south-central Montana, was examined by Paul T. Allsman, an engineer of the Bureau of Mines, in 1939. Because of the strategic importance of nickel, a project was executed by John East, Jr., J. J. Naughton, and E. W. Newman, engineers of the Bureau, to further delimit some of the copper-nickel sulfide-bearing bodies that had been discovered by the Anaconda Copper Mining. Co. in 1937 and to investigate the central part of the deposit, which had not been drilled previously. This report is based largely upon the results of the. Bureau of Mines investigation and the results of exploration by the Anaconda Copper Mining Co. In addition, a brief description is given of some other copper-nickel sulfide-bearing deposits along tho Stillwater Complex.

Jan 1, 1949

By Masayuki Ishikawa

In a radio frequency and optoelectoronic device packaging, Gold-Tin (Au-20 wt% Sn eutectic) solder is used widely due to the excellent electrical and thermal conductivity, high strength, and negligible creep characteristic under repetitive thermal cycling. With the recent lead-free movement, Gold-Tin solder is recognized as an alternative material for high temperature Lead-Tin solder. Generally, Gold-Tin solder is supplied in the forms such as ribbons, pellets, and ring frames. However, these forms must be set-up accurately on the joint area to press chips in bonding, therefore, it is difficult for these forms to satisfy the recent requirements for the down sizing in the connection areas. On the other hand, Au-20 wt% Sn solder paste can be applied flexibly to various supplying methods, such as printing, dispensing system and pin transcript. These methods also make it possible to reduce the production cost. However, in the case of using the solder paste, the void issue is one of the most undesirable problems. The void causes the degradation of the characteristics such as the bond strength, electrical characteristic and thermal conductivity. We have been intensifying the development of the void free paste, and have achieved void reduction by optimizing the powder size, the flux composition and the reflow condition.

Oct 1, 2003

By R. Agius, A. Nacu

"Adoption of the International Cyanide Management Code, regulatory requirements and community concerns have increased the need to implement suitable cyanide destruction processes at gold operations to meet ever more stringent discharge limits. As standards set for the allowable concentrations of cyanide, cyanide compounds and other contaminants may vary from country to country, jurisdiction to jurisdiction, and even from site to site, there is no “one size fits all” technological solution. Currently the most common cyanide destruction processes used in industry are sulfur dioxide/oxygen, hydrogen peroxide and Caro’s acid. Regardless of the process used, cyanide destruction plants must be reliable and achieve permit guidelines at all times. The selection of the most appropriate cyanide destruction process for an operation depends on several factors, including permit discharge requirements, tailings chemistry, location, site-specific climatic conditions and size of the operation. Only after considering all these factors together can the most effective approach be selected to achieve the permit guidelines economically and technically feasible. Finally performing the correct test work program is the most important step to ensure that the correct process design criteria can be determined to accurately calculate capital and operating costs.IntroductionThe adoption of the International Cyanide Management Code in 2005, stricter regulatory requirements and community concerns prompted by environmental incidents involving cyanide have increased the need to implement cyanide destruction processes at gold and silver operations.Process solutions associated with the extraction of gold and silver contain several forms of cyanide. The most toxic form of cyanide is free cyanide, which can be present as a dissociated cyanide anion (CN-) or gaseous or aqueous HCN. Weak or moderately stable cyanide complexes such as those of zinc, copper and nickel are classified as weak acid dissociable (CNWAD). Although less toxic than free cyanide, weak acid dissociable cyanide complexes are considered “ecologically sensitive” forms of cyanide and are regulated in most jurisdictions. In practice, reported WAD cyanide values are comprised of both free cyanide and weak acid dissociable cyanide complexes. Cyanide complexes with gold, mercury, cobalt and iron are referred to as strong acid dissociable complexes (CNSAD) and are much more stable even under mildly acidic conditions. Another term commonly used in cyanide chemistry is total cyanide, which represents all cyanide compounds present in solution, with the exception of cobalt complexes. Total cyanide levels in solutions are in most cases higher than WAD cyanide values and the difference between the two usually indicates the presence of iron-cyanide compounds. Typically, in Canada CNTOTAL levels cannot exceed 1 mg/L in solutions."

Jan 1, 2017

By O. P. Garg

"The Iron Ore Company of Canada (IOC) operations in Labrador and Quebec, in Canada, is among the largest openpit mining complexes on a world wide basis. Since the 1981-82 recession, IOC has embarked on a comprehensive cost reduction and productivity improvement program in order to survive in the world iron ore market.This paper will outline the approach used in prioritizing the cost reduction items.IntroductionMuch of the mining industry in North America is in a crisis state. Most producers are operating at production levels well below capacity, some have been merged or sold, while others have been mothballed or closed permanently. For many of us still operating, the future is uncertain. Despite the many cutbacks and closures, there is still an abundant supply of minerals in the world market and there is almost no hope for any relief on price pressures on most mineral commodities in the near future. The Iron Ore Company of Canada (IOC) operates an iron ore mine, a concentrator and a pellet plant known as the Carol Project located in Labrador City, Newfoundland. This concentrator and the pellet plant have the annual capacity to produce 20 million and 10 million tons respectively. A company owned and operated railway links this operation with the dock terminal facilities in Sept-Iles, Quebec.In the past decade the Iron Ore Company of Canada has been one of the largest producers of iron ore products in the world. Its pellets and concentrates as well as natural ores were sold in North America, Europe and the Far East. In 1981-82, sales, particularly in North America, went into a serious decline. For almost 30 years, the gospel IOC preached to employees was ""production, production!"" There were many innovations, and millions of dollars were spent on the biggest and best equipment, on research and development, on training and developing employees."

Jan 1, 1987