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This report presents production and delivered costs for coal exports from the five major Western coal-exporting countries: Australia, Canada. Colombia, South Africa, and the United States. Cost data were compiled from visits to 43 mines by U.S. Bureau of Mines engineers between 1985 and 1990. All report costs are in January 1989 U.S. dollars per short ton. Production costs for raw coal are divided into mining and regulatory categories. Costs are broken down by type of cost, type of mine. and country. Scheduled operating and capital costs for raw coal were processed by the Bureau's MINSIM discounted cash flow program to determine total production costs calculated at 0% and 15% discounted cash flow rates of return (DCFROR). Delivered costs are for salable coal delivered to various markets. Costs are broken down by supply country, market, and type of cost. Scheduled operating and capital costs for salable coal were processed by the Bureau's MINSIM discounted cash-flow program to determine total salable coal costs at 0% DCFROR. Added to total salable coal costs were transportation and port costs to get delivered costs. Comparative overview information on the coal industries of the five study countries are appended. This appendix includes information on industry economics and exports, production and reserves, and coal industry issues.

Jan 1, 1993

By David K. Hylbert

This study was designed to investigate roof falls in room-and-pillar drift coal mines and to determine geologic methods for predicting unstable roof conditions. The study area was located in Harlan County, Kentucky and the Bailey Creek (Harlan coal bed) and Highsplint (Darby coal bed) mines were selected for study. Correlations were made laterally between surface outcrops and within the mines using lithologic and trend analysis criteria. Lithologic criteria compared cyclic changes in roof strata. Results indicated that roof falls are associated with zones of weakness within or between five vertical cycles recognized. Abrupt lateral facies changes occur. In the Highsplint mine the roof was classified in four categories or conditions using 98 rib sections for control. Structure contour and isopach maps were used to project axial trends of the sandstone roof. A roof-fall zone was examined using ten NX cores taken from the roof and included lithologic, petrographic and clay mineral studies. At the Bailey Creek mine roof failure was caused by the heading direction being driven subparallel to paleochannel directions. Computer programs were used in trend analysis studies. Cross-bedding, paleo-channel trough axis and sole mark studies indicated a 350 discrepancy between surface and in-mine trough axes at Highsplint. A direct relationship between joint and "slip" frequency and direction with sandstone roll trends was found. Surface joints compared well with drainage Segments, hilt did not correlate with roof falls in areas of mines under overburden in excess of 600 feet.

Jan 1, 1977

By Arnold O. Tanner

Tables based on 1985 data, which were not available in time for publication of the "1985 Minerals Yearbook," are included in this chapter; corresponding tables for 1986 are not yet available. Raw nonfuel minerals produced in the United States during 1986 had an estimated value of $23.5 billion, an increase of $0.25 billion over the 1985 value. This is the fourth consecutive year that the value has increased, and except for a de- crease in 1982, the value each year has increased since 1971, or 14 out of 15 years. Industrial minerals growth slowed from a 3% increase in value in 1985 to a 1.5% increase in 1986, reflecting the slow growth in the domestic economy. The value of industrial minerals, more than three times larger than the value of metals, easily offset the less than 0.5% decline in the value of metal mine production. Although the decline was small, this decrease makes 1986 the fourth year in the past 6 years in which a drop in the value of metal mining production occurred in the United States. U.S. production continued to lag behind the growing world production. Overall, the estimated raw nonfuel mineral production rose 1% over that of 1985. Domestic mine production of ferrous metals declined as follows, in decreasing order of production: nickel, iron ore, tungsten, and molybdenum. All remaining domestic primary nickel and tungsten mines had closed down by yearend. Nonferrous metals that similarly declined included titanium, rare-earth metals, lead, silver, zinc, and magnesium. For the second consecutive year, aluminum, produced predominantly from imported bauxite, declined in production, while imports reached record-high levels. Somewhat modest gains were made in beryllium and copper. As has been the case for a number of years, gold was a bright spot in the domestic and internation-al metal mining industry. Gold production was spurred on by the increasing usage and development of heapleaching techniques that make lower grade ores, which were previously uneconomical, profitable. Additionally, various mining companies, the U.S. Mint, individual States, and a number of foreign countries began production of gold bullion and commemorative coins. Gold output in the United States increased from 2.43 million troy ounces (revised) in 1985 to about 3.73 million troy ounces in 1986, a dramatic 54% rise.

Jan 1, 1988

Research 82 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information, 2401 E Street, NW., Washington, D.C. 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1982

By Joseph Grumer

About a century ago Bunsen and his associates invented the famous burner that bears his name and was to become the ancestor of today's gas appliances. Over the years, Bunsen's invention became the starting point of a highly developed, practical technology that culminated in the gas industry as we now know it. However, it did not occur to the early workers to investigate the scientific potentialities of the new device, and as a result the science of gas-burner performance did not keep pace with the growing industry. It was with the objective of closing the rapidly widening gap between science and technology that the present research was undertaken Its immediate purpose was to provide basic information on the combustion characteristics of .fuel gases, in particular as they affect flashback, blowoff, and yellow tipping. Information obtained in the present research and contained within this report consists of the following: (1) Fundamental flashback and blowoff characteristics have been determined, it is believed, for all fuel-gas mixtures in which the gas industry may be interested. These are critical boundary velocity gradients for flames in free air, on burners with ports at room temperature and pressure. Burner aeration is characterized by the parameter, fraction of stoichiometric. These basic limits are explained, values are presented, and calculation procedure is given for deriving corresponding values of port loading and percent primary air (chs. I and II).

Jan 1, 1956

By G. L. Oldright

In an earlier series of 15 Reports of Investigations on Smelting in the Lead Blast Furnace, experimental data were given on the operations of a custom smelter, a smelter treating rich lead products, and a smelter treating highly zinciferous charges. Five "reports" were written on each of the three types of operation, which were later compared in a summary written for the Institute. Developments in each of these types of operation in lead smelting since the last of the above reports was written have continued and have followed modifications necessitated by changes in the nature of the products received for smelting. The sintering-blast furnace-smelting plants have improved their sintering operation .and have made "2-pass" sintering a more standard operation; the richer lead feeds are diluted when marginal precious metal ores are not available to prevent fusion of the sinter cakes and to permit air to contact the sulfides. Means have been devised to make it easier to remove metallic lead from the wind boxes, but no attempts have been observed to use the D & L somewhat as an ore hearth to make more metallic lead. Except in those cases where zinc-rich lead blast-furnace slags were to be retreated in a "slag-fuming furnace," the sintering and the blast-furnace operations were so carried out that a relatively "clean," lead-poor, final slag was discarded.

Jan 1, 1949

By S. H. Lorain

This paper, which describes lode gold mining in Idaho county, Idaho, is one of a series on western mining districts being published by the Bureau of Mines. It describes mining and milling practices, gives costs, and discusses transportation, climate, power, labor, and other conditions that affect them. The materiel upon which the paper was based was gathered during a field survey in the summer of 1937.

Jan 1, 1938

By J. D. Noll, S. E. Mischler

Measurement and sampling of diesel particulate matter in mine air presents a challenge due to the complexity of the diesel aerosol. The results of a series of tests carried out by the National Institute for Occupation Safety and Health, Pittsburgh Research Laboratory, in an underground mine were used to evaluate several measurement methods that are currently used to characterize particulate matter emitted by diesel-powered equipment. This paper presents an overview of these techniques and examples of the results along with a discussion of the advantages and information gained by each technique. The measurement methods discussed include particle size measurements using a scanning mobility particle sizer, total particulate matter measurements using a tapered elemental oscillating microbalance, a size selective sampling method for workplace and personal exposure assessment and a size-selective high volume sampling method for carbon analysis.

By F. A. Rutledge

[An a part of the United States Department of the interior program for the development and use of Alaska raw materials, the Bureau of Mines is conducting an investigation of deposits of nonmetallic minerals accessible to the Alaska Railroad for use in building; materials is In the Alaska Railroad-belt area. The results of the investigations, to date, indices that raw materials for the preduction of brick products are in plentiful supply as cloy in the Anchorage area, as fire clay at Sheep Mountain, and as shale in the Healy Creek coal formations near Healy, Alaska.]

Jan 1, 1953

By Wilson Blake

Rock preconditioning in advance of mining was shown to be an effective means of rock-burst control based on the results of a field demonstration carried out on the 7700 level of the Hecla Mining Company's Star mine. Mining through the preconditioned zone was characterized by greatly reduced rates of released seismic energy and no bumping or rock bursting occurred within the preconditioned zone. Mining above the preconditioned zone was characterized by greatly increased rates of released seismic energy and rock bursting, particularly where the vein became very narrow in waste zones. This increased incidence of rock bursting points out the need for stope preconditioning to be carried out on an entire stope block basis. The data obtained from the monitoring of the mining above the preconditioned zone on the 7700 level will be extremely useful in evaluating any future stope block preconditioning experiments on the lower levels or the Star mine.

Jan 1, 1980

By S. H. Ash, E. M. Brooks

"Many of the hoisting slopes at the mines in the State of Washington are driven on extra steep dips. To facilitate hoisting they are driven wide enough to provide two tracks. The cars are handled by high-speed, first-motion electric hoists and the trips run in balance.The State mining laws a provide that special man-cars be provided on slopes of 20° or more and that no one be allowed to ride while any loaded car is being hoisted in any slope in a mine. Obviously, in addition to the fact that it is more or less hazardous to ride while an empty trip is being hoisted, considerable hoisting time is lost during the day if some one has to ride the trips in the slope.Owing to the locations of pumps and various types of equipment, more or less travel is required up and down the slope. Not only to provide a proper safety factor but also to comply with the law, some other means of transportation in an¬other passageway is desirable. This is sometimes recognized in large mines by pro viding separate hoisting shafts, or slopes, and necessary equipment, which are use for transporting men and material. The handling of material in itself would justify the system in most large mines.The following description of an automatic electric man-hoist was prepared from data furnished through the courtesy of Mr. Thomas Murphy, superintendent of the Northwestern Improvement Company's mines in the Roslyn-Cle Elum coal field.The special features of this hoist are that no hoistman is required and its operation is always under the control of the person or persons riding the trip.The hoist was installed at mine No. 5, Roslyn, Washington, to provide a means of entering and leaving the mine on idle days or at night when no hoistman was on duty and to make it unnecessary to use the main hoist for a man trip during working hours. It has been in operation for about two years and has given very satisfactory service.The hoist, with all accessories, is housed in a concrete building 200 feet back from and in direct line with one of the main airways. One car with a capacity of six men operates over a distance of 1,200 feet on a 38° pitch.The wiring details of the electric circuits which control the operation of the hoist are shown in Figure 1-a.The hoist is driven through a worm gear by a 500-volt shunt-wound direct-current motor at a car speed of 120 feet per' minute. A gravity friction brake with magnetic release is mounted on the- motor shaft and is wired in multiple with the motor field coils. The hoist drum is also equipped with emergency friction brakes, which operate by gravity and are released, in case of overspeed, by the governor geared direct to the drum shaft. When these brakes set the control circuit is opened at contact 2E-2C and the motor stops.If the descending car meets some obstruction and is stopped, the hoist continues to run and unwind the rope. To guard against this occurrence, a weighted sheave wheel rides the rope 4 feet from the drum, and if the rope becomes slack the rider drops downward and opens the contact 2C-2E which stops the hoist.Limit switches, S1 and S2, are located on the hoist indicator, which is connected to the drum shaft through sprockets and chain. The pointer P indicates the position of the hoist at all times."

Jul 1, 1930

By Lloyd Williams

1. The investigation shows that the Poplar Creek and Big Mary beds contain the largest known recoverable reserves of coal in Morgan County, Tenn. The Poplar Creek bed has been the most productive. 2. Known measured and indicated reserves of coal, based on a minimum bed thickness of 14 inches and on 1,800 short tons per acre-foot of coal in place, are estimated to be 96 million tons, as of January 1, 1954. Of this total, 59 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics were too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1956

By Clarence Karr

AN EXTENSIVE characterization was conducted on the neutral oil components in a low-temperature bituminous coal tar. A total of tai individual compounds identified with respect to individual isomers, and at least 55 other compounds were indicated to be present. The amounts were determined in all instances. A comparison of isomeric distribution in the tar with thermo-dynamic equilibrium distribution, and kinetic distributions indicated that the composition of the tar largely reflected the structure of the coal from which it was formed. Detailed descriptions are presented for the separatory and qualitative and quantitative procedures for the characterization of the neutral oil component. These include micro fractional vacuum distillation, displacement liquid chromatography, gas-liquid chromatography, countercurrent distribution, and infrared and ultraviolet spectrophotometry. Descriptions are given for the synthesis of authentic specimens of alkylindenes, The ultraviolet and infrared spectra of 134 polycyclic compounds, ranging from alkylindenes to alkylphenanthrenes, either found in the distillable neutral oil, or thought likely to be present, are also given.

Jan 1, 1967

By Bryan Buchholz, N. Kumar Kittusamy

Previous studies indicate that operators of heavy construction equipment are afflicted by musculoskeletal injuries of the arms, shoulders, neck, and lower back. These injuries appear to be due to excessive periods of sitting (static posture), work intensity, whole-body vibration, high resistance levers, repetitive motions, and awkward postures. (2-5) Although numerous studies have shown an association between operation of heavy construction equipment and symptoms of musculoskeletal disorders, very little research has been performed that systematically characterizes operating engineers' exposure to ergonomic hazards. The objective of this study was to systematically characterize the ergonomic hazards associated with excavating operations. As such, the following were performed: (1) vibrations were measured at the operator/seat interface (X, Y, and Z axes), and at the floor of the cab (Z axis); (2) psychophysical ratings of whole-body vibration (WBV) level and overall seat design were obtained; and (3) postural assessments of the job were made. Methodology This study evaluated an inexperienced female operator performing excavation, utilizing two different pieces of equipment. The operator was 37 years old, 162 cm tall, and weighed 80 kg. She had approximately 15 hours of operation time (experience) on the equipment evaluated. The two pieces of equipment used were: a Case Super 580E (1986) backhoe/loader, and an Insley H-2000 excavator (1975) (see Figures 1 and 2). More evaluations were performed on the backhoe/loader than on the excavator. The following evaluations were performed on the Case equipment: 1) vibration levels at the seat and floor; 2) psychophysical ratings of the overall seat design and vibration levels (for the task duration, and for an 8 hour duration); and 3) postural assessments. For the Insley equipment, all of the evaluations were performed except vibration measurements. When the evaluations were conducted, the following environmental conditions were noted: the temperature was 31°F, and soil and terrain conditions were rough and frozen.

By Anthony E. Szczuka

Two facets of surface mining were studied: feasibility of using training simulators to increase productivity of haulage trucks, front-end loaders, and shovels; and improving the efficiency of dragline operations with a computer-aided analysis of dragline usage and the addition of an on-board operator display. Training costs per student were estimated based on current training practices. Training objectives were derived from task: analyses of haulage trucks, front-end loaders, and shovels. The cost effectiveness of training simulators was determined. A computer-aided analysis defined the critical performance parameters. An on-board operator's display is recommended to improve operator efficiency.

Jan 1, 1976

By C. B. Manula

Bituminous coal mining in the United States is currently experiencing a period of rapid growth which began in the early 1960's. Future demands are conservatively predicted to rise to 700 million tons by 1980 and to anywhere between 1 to 3 billion tons by the turn of the century. This means a continuous expansion of coal production by a factor of at least two can be expected before the end of the century. Over the last few years, production from underground mining has decreased; yet it is about 50% of the total coal output. In the absence of any discovery of near surface coal deposits, and even after conceding that some deeper deposits can be surface mined with changes in technology it can be reasonably assumed that coal production from underground will continue to play an important part in solving the energy crisis.

Jan 1, 1975

There has been a substantial increase in the use of rubber-tired front-end loaders in the mining industry in recent years. Concurrent with this increased usage, in the period of 1966 to 1970, there were at least 74 mining industry fatalities involving front-end loaders, or (on the average) in excess of one fatality per month. When the usage of front-end loaders by the construction industry and other industries, organizations, and agencies, such as the Government (i.e., Department of Defense), along with the uncounted numbers of serious, but non-fatal accidents, are included in the picture, the safety record for front-end loaders, of necessity, becomes a serious subject for study. There is an urgent need for attempts to be made to eliminate or reduce the number of safety hazards; to decrease the confusing diversity of controls designs found on present front-end loaders; to improve the maintenance and operating procedures; to formulate better personnel policies; to increase management and official awareness of the extent of the problem, in both industry and the Government; etc.; in order to decrease the number of accidents. Part of the problem may be traced to the fact that the operator of a front-end loader is frequently designated a "heavy equipment operator." This implies that he is automatically qualified to operate any model, of any manufacturer's, wheeled or tracked, front-end loader as well as many other types and classes of heavy equipment. Contrary to automotive practice, the complement of primary operating and emergency controls varies widely from model to model, as well as from manufacturer to manufacturer. Not only are certain controls present on one front-end loader model and absent on others, but there are significant differences in the modes of control operation, in the functions performed by superficially similar controls, in the location of the various controls, etc.

Jan 1, 1973

By Robert Louis Adams

A general discussion of the structure of the junk automobile recycling system shows that the generation of stripped automobile hulks and scrapped automobiles is price inelastic. As a result, it is extremely difficult for the price mechanism to automatically achieve an equilibrium that will prevent the accumulation of excessive automobile wrecker inventories and vehicle abandonment by the last owners of scrapped cars. The new shredder processing technology and the new portable flattener technology have altered the structure of the junk automobile recycling system. The shredder technology has increased the demand for processed automobile scrap. This increased demand is reflected in higher prices paid for hulks by scrap processors. The portable flattener has reduced the transportation cost of shipping hulks to processors. The two new technologies have eliminated, at least potentially, the net cost of shipping stripped hulks so frequently incurred by wreckers in the past. The elimination of this cost eliminates the economic incentive for excessive wrecker inventories. Unfortunately, the incentive for last owners to abandon their cars does not appear to have been eliminated by the new technologies. The last owner of an automobile with no spare parts value is still likely to incur a cost by delivering his automobile to the recycling system. Although a subsidy payment is probably unnecessary to reduce excessive wrecker inventories, such a payment might be one solution to the problem of automobile abandonment. However, there are a wide variety of subsidy programs that could be introduced. Before any Federal subsidy program is introduced to reduce automobile abandonment, it is recommended that the program be tested on a limited basis in many different parts of the country.

Jan 1, 1973

By Douglas D. Reynolds

Intense vibration can be transmitted to the hands and arms of workers who use hand-held percussive or vibrating devices, tools, and work pieces. Continued habitual exposure to vibration directed to the hands can cause patterns of various symptoms associated with hand-arm vibration syndrome (HVAS). The International Organization for Standardization (ISO) first published ISO 5349 in 1986.3 This standard specified methods for measuring and evaluating vibration directed into the hands from hand-held vibrating devices, tools, and work pieces. The American National Standards Institute (ANSI) published ANSI S3.34 the same year.1 This standard was modeled after ISO 5349-1986 and specified methods for assessing exposure to hand-arm vibration. The Parliament of the European Union has issued the European Union Human Vibration Directive-2002/44/EC, which specifies vibration daily exposure action values (DEAV) of 2.5 m/s2 and daily exposure limit values (DELV) of 5.0 m/s2. These values have generally been accepted by medical experts, scientists, and engineers in governmental agencies, research institutions, and industry in the USA and other countries.2 When they are achieved, they will reduce the potential for the development of symptoms related to HAVS among workers exposed to hand-arm vibration. Significant improvements in measurement and analysis instrumentation, miniature and subminiature accelerometers, and medical diagnostic and assessment protocols have being introduced since 1986 when ANSI S3.34 was first published. In response to these improvements and the introduction of the EU Human Vibration Directive, ANSI Working Group S2.39 developed the revision to ANSI S3.34, which has now been published as ANSI S2.70-2006.2 Method ANSI S2.70 specifies the use of the hand-arm vibration measurement procedures outlined in ISO 5349, Parts 1 and 2.2,4,5 It requires the measurement of ISO frequency-weighted acceleration values in three mutually orthogonal axes of vibration. These values are then vectorially added to obtain the vibration total value, ahv: [ ] where ahwx, ahwy, and ahwz are the measured r.m.s. ISO frequency-weighted acceleration values in the x, y, and z directions, respectively. If multiple vibration exposure events are experienced during a work day, the overall vibration total value is obtained from: [ ] where ahvi is the vibration total value of the ith operation, Ti is time duration in hours of the ith operation, n is the total number of operations, and T is total time in hours associated with the n

Jan 6, 2006

By H. C. Fowler

The social economy, or public interest, and national defense require wise development and efficient use of the oil and gas resources of the United States. In this development and use, and in the prevention of economic and physical waste of oil and gas, the objectives of the petroleum and natural-gas industries, the Government (Federal, State, and local), and the public are the same. Differences of viewpoint generally have originated in the failure of one of the triad to have a clear or complete understanding of the motives behind the activities of the other component groups or full knowledge of what each is trying to accomplish. The Unites States Bureau of Mines through its petroleum and natural-gas division makes technologic and scientific investigations pertaining to recovery,3 preparation, refining, and use of oil and natural gas with the view of reducing waste, increasing safety and efficiency and aiding economic development.

Jan 1, 1933