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By J. Hansen

This paper has been written for presentation during the Open Pit Mining Session at the SME Annual Meeting and Exhibit, Denver, Colorado, February 26 to 28, 2001. The paper addresses the application of automated monitoring of electric rope shovels to improve performance and blasting technique.

Jan 1, 2001

By V. Arslan

In this study, effects of the inert constituents, such as ash, and the effect of blending coals with differing rank and composition on the plasticity of coal blends were investigated. The reference coal originated from the Zonguldak region, in the north-west part of Turkey. Firstly, the effect of coal ash on the plasticity of Zonguldak coal was determined. Secondly, the relationship between the plastic properties of the individual coals and those of the blended coals were identified. Some important relations were found, related to the characteristics of the individual coals. Ultimately, the manner in which the plasticity of Zonguldak coal was affected by blending with low volatile coals was investigated. Keywords: coal blending, coal plasticity, coke, fluidity, rank.

Jan 1, 2006

This is the third in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C. F. R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ The second report gave the same data for motor gasolines sold during the summer of 1936)4/ As was the case with the first cooperative gasoline survey, reports were received for some areas from only one company and in other areas from two companies that did not in all instances report on the same brands of gasoline. In still other areas reports were received from five or six companies on the same brands of gasoline. Thus, it can be seen that data on gasolines are unequal in regard, to the number of reports that were averaged in calculating the data shown in table 1. The data from the Pacific Coast were averaged by the Pacific Coast technical group before submission and are published exactly as they were submitted.

Jan 1, 1937

By D. McBride

Representative samples are required from process streams in order to accurately measure chemical and physical characteristics. This information can then be used by process operators and metallurgists to evaluate the process and effect control actions for the operation. The capture and presentation of representative samples can be critical to measuring values, such as elemental analysis and particle size, with on-line or near-stream analyzers. A comprehensive multi-physics model has been developed and used to better understand the effects of slurry flow and particle segregation under certain operating parameters. An algebraic slip model coupled with a free surface algorithm is used to track motion and position of particles and phases within a specified geometry.

Jan 1, 2009

By Antoni Kalukiewicz

From 1997 through 2000, a team of Polish experts headed by the author studied the prospects of mining newly discovered emerald deposits in Afghanistan. This article describes the scheme for mechanization of the mining operations, along with improvements made to the ventilation facilities and lighting. The required equipment was flown to Afghanistan and the Afghan miners were trained in machine operation and maintenance.

Jan 1, 2005

This is the third in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C. F. R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ The second report gave the same data for motor gasolines sold during the summer of 1936)4/ As was the case with the first cooperative gasoline survey, reports were received for some areas from only one company and in other areas from two companies that did not in all instances report on the same brands of gasoline. In still other areas reports were received from five or six companies on the same brands of gasoline. Thus, it can be seen that data on gasolines are unequal in regard, to the number of reports that were averaged in calculating the data shown in table 1. The data from the Pacific Coast were averaged by the Pacific Coast technical group before submission and are published exactly as they were submitted.

Jan 1, 1937

By Ralph H. Sweetser

MUCH progress in -blast-furnace construction and in the manufacture of firebrick for furnace linings has been made since the publication of Bulletin 130 of the U. S. Bureau of Mines on "Blast-Furnace Breakouts, Explosions and Slips, and Methods of Prevention," by F. H. Willcox in 1917. At the time of publishing this report comparatively little information was available to blast-furnace men as to the fundamental facts relating to the character of blast-furnace refractories. Some of the accepted theories of only a few years ago have been completely reversed. The mortality of blast-furnace linings used to be so great that nearly every furnace plant had one or more complete linings in the brick shed ready for use in case of a lining suddenly "going out"; it was generally accepted that a furnace could not "keep her lines" more than two or three years at best, and often a hot spot in the shell would develop, or a breakout occur in the hearth or bosh within a year or two after blowing in on a new lining. In some respects these frequent relinings were not so detrimental as to he a complete loss because they afforded opportunities to take advantage of advances in blast-furnace practice. At present the cost of relining has greatly increased, but the life of a lining has also increased. Anything less than five years on a lining is now considered a short blast.

Jan 1, 1932

By John Watson, Jay Rodgers

The world of blasting and explosive use continues to evolve into one which relies heavily on measurement, quantification, process control, and information feedback as a means of contributing to operational improvements. More than ever good blast performance, once thought to be a result of someone’s “artistic ability”, is giving way to “hard science” and measurement techniques. Variability in product performance and process control is becoming less tolerable with increasing environmental issues, regulatory pressure and public awareness.

Jan 1, 1998

By W. P. Yant, R. R. Sayers, H. W. Shoaf, John Chornyak

"The contemplated use of dichloro-difluoro methane in domestic and commercial refrigerating appliances and in air-conditioning equipment for Public buildings and possibly homes, brings attention to the health hazards involved in a wide potential exposure of the public to vapors of another new product, and for the first time to vapors of an organic fluorine compound. The objective in the development of this new refrigerant, however, has been the mitigation of health and explosion hazards in automatic refrigeration, and accordingly these factors have been given primary attention. Early in the development, the Bureau of Mines was requested to make a laboratory study of the toxicity and potential hazard:"" and it was on the basis of the results of this work and the results of a preliminary investigation made in another laboratory5 that the compound has been selected for commercial use. Although the investigation conducted by the Bureau of Mines is still in progress, information has been obtained to indicate the order of the toxicity and the magnitude of the health hazards involved in the use of dichloro-difluoro methane as a refrigerant. The following is a summarized report of the work completed to date:Additionally work rich is in progress at the present time includes a determination of the lethal time-concentration curve for animals and a study of the response of persons within the range of safe concentrations.The writers desire to jive acknowledgment to T E. Midgley, Frigidaire Corporation, Layton, Ohio, for suggesting the investigation, for arranging for the cooperation of the Frigidaire Corporation, and for advice during the experimental work; to Robert A. Kehoe, The Eichberg Laboratory of Physiology, University of Cincinnati, Cincinnati, Ohio; and E. R. Hayhurst, college of Medicine, Ohio State University, for consultation and advice in planning the work; and to the following employees of the Bureau of Mines for assistance in performing the experimental work: L. M. Berger, chief scientific aid, S. J. Pearce, junior chemist, and Ethel B. Stead, technician."

May 1, 1930

By D. Wolfe, R. Cleminson

"The Aurora North mine has been operating for more than ten years, and is the source of over half of Syncrude’s bitumen production. The slurry systems at Aurora experience high rates of wear, and mission lengths on current slurry pumps are nominally 1500-2000 hours. Recent work has enabled a better understanding of the significant adverse effect of large particle impingement damage to impeller vane leading edges - which is the known life determining issue for Aurora hydrotransport pumps. A new pump design has been developed with a larger diameter impeller and increased vane lengths, and is expected to triple Aurora’s mission length for hydrotransport pumps.INTRODUCTIONSlurry Pumps are Critical Equipment at SyncrudeSlurry pumps are a critical component in Syncrude’s operations. In a typical Aurora application, each pump stage helps move over 8000 dry tonnes per hour of oil sand, plus an equal volume of process water that has been added to create the slurry. The average impeller life in oil sand hydrotransport service at Aurora has been nominally 1500-2000 hours, or 12-16 million tonnes of oil sand pumped. Generally, the slurry pump application at Aurora has proven very difficult to improve due to the unique combination of high sand abrasivity, 125 mm (5”) large particle top size (lumps), and high flow rate relative to basic pump size; a factor that results in higher than optimal impeller vane speeds for the service conditions.PROJECT BASISSlurry Pumps are the Reliability Bottleneck at AuroraSlurry pumps are currently the shortest-lived components that determine the overall system run length at Aurora, in Hydrotransport, Extraction and Tailings. Vibrating screens and piping had been previous bottlenecks, but their reliability has been improved through upgrades in equipment design and wear materials. Both vibrating screens and piping can now achieve 4000 hour mission lengths."

Jan 1, 2013

By B. Waterman, D. Ramey, L. Schlink

"Water is a primary commodity for most industrial processes. It has become a global focus in light of climate change and population growth. Reuse of process water has two major benefits - minimize the amount of fresh water added now and minimize the amount of discharge water that requires treatment later.Mining and mine product processing has its share of reused water. For example, reclaim water from a tailings impoundment, overflow from thickeners and leach solution to raffinate and back again all demonstrate the use and reuse of water in mining circuits. Eventually, a mine reduces production or ceases operations completely, eliminating the option to reuse the impacted water and, thus, requires treatment of the remaining water.Current methods of water treatment remove the impacts, providing clean water for discharge, but leaves behind a concentrated waste that requires further treatment or disposal of a hazardous waste. Freeport- McMoRan is currently testing three water treatment technologies specific for sulfate and/or metal removal from mine impacted water with the approach of transformation not concentration. These technologies provide clean water for alternative use while creating byproducts that could be marketable, or disposed as a nonhazardous material, thereby reducing the cost and longterm liability of disposal.The selection of a water treatment process is site-specific. The volume of water, contaminant to be removed, disposal options, length of time for treatment, location of plant and reagents and discharge requirements are some of the factors that need to be considered when selecting a water treatment process. Common water treatment technologies for mine impacted water consist of low- or high-density sludge (LDS/ HDS), reverse osmosis (RO) and evaporative technologies. In addition to operating costs, these processes require additional handling of the concentrated sludge or brine. Advanced water treatment technologies include ion exchange, solvent extraction and metals precipitation with or without the aid of a biological system. Some of the more complex systems have a series of unit operations to achieve required discharge regulations."

Jan 1, 2014

Recently, work was carried out by the Shotcrete Working Group to study anisotropy in steel fibre reinforced shotcrete using strain-controlled, compressive strength testing methods. The shotcrete materials used and specimen preparation procedures as well as testing methods are described. The test results are discussed and it is concluded that, because of the anisotropic nature of fibre reinforced shotcrete, it may be worthwhile investigating the degree of such anisotropy in practice using strain-controlled, strength testing techniques.

Jan 1, 2001

By J. Noll

Many underground metal/nonmetal mines are using enclosed cabs on mining equipment to reduce the exposure of miners to diesel particulate matter (DPM). However, some enclosed cab systems may not be meeting their expected efficiency in capturing DPM, which could be a result of inappropriate filter use, cab leaks, or insufficient pressurization. NIOSH investigated several types of filters for reducing DPM to determine which type had the best capture efficiency. The laboratory results indicated that a MERV 8 (Minimum Efficiency Reporting Value, as defined by the American Society of Heating, Refrigerating and Air- Conditioning Engineers) filter captured about 50 percent of the DPM, a MERV 16 filter collected 96-98 percent of the DPM, and two HEPA (high efficiency particulate air) grade filters captured over 99 percent of the DPM. NIOSH also performed a field study to measure the efficiency of two cabs at a limestone mine. The cab filtration systems of a loader and haul truck were found to be over 90 percent effective in removing DPM except under certain operating conditions when the efficiency was as low as 41 percent. Evidence seems to suggest that these conditions were when a window was open in the cab.

Jan 1, 2011

By Foster Fraas

One of the lithium minerals most widespread in the earth's surface is spodumene (Li2O-A1203-4Si02) a lithium aluminium silicate. For some time, deposits of this mineral were known to exist in the Black Rills of South Dakota, but it was only quite recently that Hess4/ pointed out the great magnitude of the low-grade e deposits it s in North Carolina. The theoretical lithia (Li20) content of spodumene is 8.04 percent. The only other minerals with such high lithia content are the phosphates, but these occur only in pockets and are not in extensive deposits5/. Actually, however, the lithia content in spodumene is never found to be this high, being nearly always below 7 percent for the pure mineral, and part of the lithia is apparently replaced by other alkalies.

Jan 1, 1937

By J. Tuzo Wilson

Abstract A division of part of the Canadian Shield into provinces believed to represent former mountain belts is attempted, special emphasis- being laid upon radioactive age determinations, the relation of Archaean to Proterozoic rocks, and the structure of the Grenville province. Original data on the distribution of radioactivity within several batholiths and their connection with ore deposits are' presented. The possible growth of continents and a theory which explains the shape and distribution of the world's younger mountain and island areas are discussed and applied to the Canadian Shield in an attempt to explain how the growth and present structure came about. The relation of the major mining camps of northeastern Ontario to fault zones is discussed in the light of this theory. Introduction The valuable symposium issued by this Institute to celebrate its jubilees emphasizes the important role of major faults in determining the location of many ore deposits in the Canadian Shield. Many of these faults are known to extend for long distances. It is therefore widely appreciated that it would be of great value if the pattern, ages, and causes of these faults were better understood. This would be particularly useful if the relations of the major fault systems to petrological and metallogenic provinces and to former mountain belts could be established. Each year the volume of available data, and hence the chance of reaching a fuller solution of this problem, increases. This article is a review of the present situation. It is accordingly based almost wholly upon the work and ideas of others, which are gratefully acknowledged. Naturally, responsibility for the selection and marshalling of the data is the writer's.

Jan 1, 1949

By George S. Rice

"""To prevent the propagation of mine explosions, the Bureau of Mines, Department of Commerce, recommends rock-dusting all coal mines, except anthracite mines, in every part, whether in damp or dry condition. It also recom¬mends that rock-dust barriers be used to sectionalize the mine as additional defense; but these should not be regarded as a substitute for generalized rock-dusting."" (Mine safety decision, No. 5, April 7, 1927.)The purposes of this circular are to present concisely the requirements for effective rock-dusting of coal mines in order to prevent propagation of mine explosions, and to point out the principal related facts on explosibility of coal dusts and mixed coal-mine dusts, as determined by extensive testing in the Experimental Mine of the Bureau of Mines. study of these principal facts on coal-dust explosibility in conjunction with the recommendations for rock-dusting, should help to make clear to mine operators and others concerned the necessity for systematic rock-dusting in all coal mines except anthracite mines, and the futility of inadequate or sporadic rock dusting.The descriptions of nearly 1000 explosion tests in the Experimental Mine are available in a forth-coming bulletin2 and in earlier publications.3For detailed specifications as to the kind of rock-dust, amount to use, where to be applied, and method of sampling and testing, the reader is referred to Bureau of Mines Serial 26064, and American Engineering Standard Committee ""Recommended American Practice for Rock-Dusting Coal Mines"" quoted in Bureau of Mines Information Circular No. 60305.Summary of Specifications for Rock-Dusting1. Mines to be rock-dustedAll coal mines, except anthracite mines, should be rock-dusted.2. Extent of rock-dustingAll open accessible parts of a coal mine should be rock-dusted, including slopes, entries, cross,-cuts, and rooms, headings and pillar workings to within at least 50 feet of the face.3 Amount of rock-dustingAfter cleaning up the coal dust as thoroughly as practicable, sufficient rock-dust should be used to have the mixture of remaining coal-dust plus the rock-dust in any zone contain 65 per cent or more of inert or noncombustible matter. First dusting may require 3 pounds to 5 pounds per linear foot of passageway.4. When to rock-dust In any zone or section (made by dividing the mine for rock-dusting purposes) when the incombustible content falls to 55 per cent, that section should be re-rock-dusted so as to bring the incombustible content well above 65 per cent."

Jun 1, 1927

Review on Some Research Methods of Mineral Crystal Chemistry and Computer Simulation on Flotation

Sep 13, 2010

By John A. Johnson

For the purpose of comparing the amounts of dust produced by various mining operations, samples of atmospheric dust were collected during a complete cycle of drilling, blasting and mucking at or near the face of the Bureau's Mount Weather testing adit while the efficiency of several types of stemming in metal-mine blasting was being investigated. ACKNOWLEDGMENTS All gas samples were analyzed in the laboratory of the Bureau of Mines Gas Section at Pittsburgh, Pa.

Jan 1, 1939

By Sengpasith Houngaloune

Arsenic, which is a toxic and carcinogenic element, causes serious environmental problems throughout the world. It is also known as a major contaminant in the non-ferrous mining and extractive metallurgical industries, thus its disposal is one of the most important environmental issues for the mining and metallurgical industries. In order to ensure a safe disposal environment for the final wastes, stabilization of arsenic has been studied extensively with various approaches. Solidification/stabilization (S/S) represents one of the most effective methods to reduce the availability of arsenic in soil and waste by transforming toxic or potentially hazardous phases into less hazardous ones. Cement based S/S processes could reduce the solubility of arsenic in solid waste, using inorganic binders such as cement, lime, and pozzolanic materials. A new tailings management technique, called cemented paste backfill (CPB), has become widely employed for improving mining techniques and for tailing storage purpose and this technique could also enhance arsenic stabilization, by fixing the contaminants in the binder matrix. Disposal of arsenic in the form of scorodite (FeAsO4?2H2O) has been widely accepted as currently the most suitable method for stabilization and the safest known storage material. The Bio-scorodite process has been reported to be more economic and environmentally friendly method than the chemical crystallization processes. Retention of arsenic by schwertmannite (Fe8O8(OH)6SO4), a metastable ferric oxyhydroxy sulfate mineral, has gained more attention in the recent years. Schwertmannite has a large specific surface area and high capacity to adsorb arsenic in solution. Several researchers have reported that the transformation of schwertmannite to goethite could be retarded by the presence of adsorbed arsenic; therefore schwertmannite might be viable alternative for long-term storage of arsenic. In this paper, various approaches used in arsenic stabilization are reviewed with emphasis on the development in the recent years.

Aug 1, 2013

Flotation of Smithsonite by Using Siloxane Cationic Surfactants as Collectors

Sep 13, 2010