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By Richard P. Cislo

The evaluation of the effectiveness of the time domain Coal Interface Detector developed by the General Electric Company under contract H0155120 is the subject of this report. The sensor utilizes differences in the time characteristics of shearer vibrations as sensed by an accelerometer mounted on the ranging arm to discriminate the cutting of coal and rock. Pour identical time domain sensors were supplied by the Bureau for field evaluation. The performance of the time domain sensor was evaluated by an extensive field test and data collection program that included four longwall mines and a total of nine mine visits. The intent was to determine the sensor's applicability to a wide range of mining conditions and to document its limitations. Results of the extensive field tests indicate that shearer vibration data processed by GE's time domain signal processing algorithm cannot be used to reliably detect when the cutting drum crossed the coal/rock interface.

Jan 1, 1987

The Bibliographic Data Base is the result of a literature search con-ducted as one task of the technology assessment of current and advanced logging techniques, sponsored by the United States Bureau of Mines. After compilation, the bibliography was converted to an automated form for ease of utilization, and to allow for maintaining and updating the data base. The data base covers articles, symposia, books, patents, corporate and government reports, and other literature concerned with some aspect of borehole logging from January 1969 through December 1975. Periodic up-dating will be necessary to keep the data base contents in step with developments in the rapidly advancing field of application of borehole logging to mining. Many bibliographic indexes were scanned for entries relating to the subject of interest, and those entries which were included in our data base contain a reference to the bibliographic index in which they were listed (see Section 2.4.7). With the aid of these indexes, a vast number of publications, including foreign reports and publications, have been scanned for works relevant to borehole logging technology.

Jan 1, 1976

By John B. Gayle

The Bureau of Mines has designed and constructed an experimental coke oven, using a commercial oven as a model where practicable. Because the rate of carbonization is important in determining the quality of the coke produced and may affect the "mount of pressure developed during carbonization, particular attention was given to those elements of the design that govern the heat transfer to the charge. The new oven deviates in design from most existing test ovens in that the charge is full width (17 inches), the heating walls ore constructed of 4-1/2-inch silica brick, and zoned, heat-input arrangements compensate for heat losses at the ends, top, and bottom of the charge. This report describes the oven, which was designed by H. S. Auvil and installed under his direction, at the Southern Experiment Station, Tuscaloosa, Ala., while he was supervising, engineer, Coke Section. It gives the results of a limited number of carbonizing tests. These results indicate that the main objective in designing and building this oven, that off duplicating commerical, slot-oven carbonizing conditions, has been accomplished; if coke-discharge conditions simulate commercial-oven conditions, the cokes from the experimental oven arc very similar to oven coke, in soma tests being fully as close is duplicate tests from a Angle batch of coke.

Jan 1, 1952

By Charles D. Litton

This U.S. Bureau of Mines report describes the results of two large-scale tests conducted to evaluate a prototype nitric oxide (NO)-compensated carbon monoxide (CO) fire sensor, developed by Carnegie Mellon Research Institute (CMRI). In the tests, small coal fires were allowed to develop in the presence of diesel exhaust at relatively low ventilation airflows. These tests compared the response of the CMRI fire sensor with that of other fire sensors, including the Bureau's diesel-discriminating smoke detector. During the tests, CO, NO, and smoke levels were continuously monitored in order to determine the sensor alarm times and gas levels as the fire developed. The data indicated that the NO-compensated CO fire sensor was capable of suppressing the CO produced by a diesel engine and that the sensor responded reliably to the CO produced from the test fires. The tests also showed that the Bureau's diesel-discriminating smoke detector alarmed earlier than the prototype NO-compensated CO fire sensor.

Jan 1, 1993

Mining men and State officials in their efforts to make mining safer are confronted from time to time with various complicated questions. In recent gears these questions have tended to increase with the use of mechanical appliances. Twenty-five years ago electricity had been used but little in mires; today there is practically no other means of transmitting power employed in American mines, except that in metal mines compressed air is used, chiefly for drilling and for operating small portable hoists. In coal mines there has been a great increase in mechanization, which tends to concentrate the work of production in small areas and to increase the local difficulties of ventilation; also, it has intensified locally the hazard from coal dust as well as firedamp in bituminous and subbituminous mines. The answers to the questions that arise are not always obvious, as is shown by the fact that even able, experienced men differ in their opinions of the best, way to overcome a particular mining hazard. The difficulty of .solving the problems is also demonstrated by the varying provisions in mine-safety rules, both in official regulations and in the rules of those mining companies that are endeavoring to do more than follow the letter of the law. Such differences of opinion as to the best way of meeting a difficult situation are often found within the same mining organization, and, similarly, varying opinions are held by different members of the Bureau of Mines staff.

Jan 1, 1937

By T. W. Johnson

One of the common methods of increasing recovery of oil from partly depleted oil sands is to inject natural gas, air, or air-gas mixtures into the sand, thereby supplying energy to move oil. into the well bore. Where natural gas is not available, air or an air-gas mixture is used as the repressuring medium. Air-gas mixtures are obtained from the casingheads of oil-producing wells in the areas repressured with air or air-gas mixtures and consist usually of varying amounts of the hydrocarbon gases, nitrogen, oxygen, and carbon dioxide. Laboratory experiments have been conducted by the Bureau of Mines to determine the effect of air on crude oils.4/ In these experiments the crude oils were oxidized by the air, and the degree of oxidation depended not only upon the chemical composition of the crude oil but also upon the duration and method of contact between the oil and air, the temperature of the fluids and the concentration of the oxygen. When the crude oils were oxidized the following results and changes in the oils were obtained:

Jan 1, 1937

By Lindsay D. Norman

Eleven major pyrometallurgical processes and operations suggested for recovering manganese from domestic resources are described. These include seven pyrometallurgical processes that usually yield a ferroalloy or a product from which ferromanganese can be produced in one operation. The remaining four involve pyrometallurgical operations whose products require either an additional two-stage process to produce ferromanganese or chemical processing to recover a high-quality manganese oxide product.

Jan 1, 1962

By E. O. Binyone

"https://www.youtube.com/watch?v=PBPyGXjlBHIhttps://www.youtube.com/watch?v=3AbtiKOYg7Y&feature=push-fr&attr_tag=uKtVW3yq2ZngptnE%3A6https://www.youtube.com/watch?v=PR2THayf-N8https://www.youtube.com/watch?v=mF-BXiWocqIhttps://www.youtube.com/watch?v=TuesIw-OZA4https://www.youtube.com/watch?v=v2HP7sTIZgEhttps://www.youtube.com/watch?v=v2HP7sTIZgEINTRODUCTIONIn 1937 the Eureka Corporation, Ltd., of Canada obtained a lease on the mining property of the Richmond-Euroka Mining Co. in the Eureka mining district, Eureka County, Nevada. In 1910 the Richmond-Eureka Co. suspended all operations except small-scale leasing, but company and other geologists contended that the El Dorado dolomite would also carry ore in its continuation from fault block north and northeast of the productive old working. The company began to explore the fault block in 1923 by diamond drilling from the,900 level of the Locan shaft, but for various reasons the hole was drilled to a depth of only 2 feet and was then abandoned. Eureka Corporation, Ltd., planned an extensive diamond-drilling program, which included four deep diamond-drill holes, one designated ""A"" fig. if it is to be drilled from the surfaced, and three designated ""E"", ""C"" and ""D"" figs land to be drilled from the 900 level of the Locan shaft. Of these only B and C were completed by the company. Hole C was a contribution,of the hole started by the, started by the Richmond Eureka Co. The site for hole D (figs. 1 and 2) was prepared, but the hole was not drilled. Both B and C holes penetrated sulfide ore carrying good percentages of zinc, lead, gold, and silver. The ore bodies were 40 feet thick and were found approximately 1,400 feet below the 900 level of Locan shaft.On the basis of the very favorable results obtained from the drilling program, the Eureka Corporation planned extensive development of the property and in 1942 commenced sinking the Fad shaft (figs. 1 and 2). The shortage of equipment and materials brought on by the war and difficulties with water in the shaft greatly hindered progress. However, early in 1943 the Eureka Cor¬poration, Ltd., of Canada submitted to the War Production Board a proposal for developing the mine and milling 500 tons of zinc-lead ore a day. The proposal involved an expenditure of $2,890,750."

Dec 1, 1946

By J. H. Soulé

This information circular is one of a series published by the Federal Bureau of Mines describing methods and costs at various mining operations. The Schwartzwalder uranium mine, situated about 20 miles west of Denver, Colo., is an important source of uranium ore in the Front Range. Production was begun in 1953, and nearly 36,500 tons of ore had been shipped by September 1, 1958. The mine is operated by Denver-Golden Oil & Uranium Co., Denver, Colo. Much interest has been shown in the property since uranium mineralization tit was found by Fred Schwartzwalder in 1949. The Atomic Energy Commission, Federal Geological Survey, Office of Minerals Exploration (formerly Defense Minerals Exploration Administration), and Federal Bureau of Mines have done work in the area, and various private concerns have shown interest in the property.

Jan 1, 1960

By James Noll

Total carbon (TC) is sometimes used to measure or characterize diesel particulate matter (DPM) in occupational settings such as underground mines. DPM samples are collected on quartz fiber filters. When using quartz fiber ?lters, adsorption of gas phase organic carbon (OC) has been reported, causing a positive bias in the particulate TC results (adsorption artifact). Most of the data on the sampling artifacts and corrections apply to environmental air sampling, where samples are collected at a much higher filter face velocity and the OC concentrations are generally much lower relative to occupational sampling. In this study, we investigated the effects of adsorption artifact on samples from occupational settings. Samples were collected with and without denuders to determine the amount of gas phase OC collected and the accuracy of certain corrections. In underground stone mines, the adsorption artifact was found to positively bias the particulate TC by greater than 20% for filter loadings below 25 µg/cm2 TC (8-h time weighted average) 262 µg/m3). The tandem ?lter correction reduced the effect of the artifact, as high as 60% of the TC value, to less than 11% for laboratory data. It also significantly reduced the effect of the artifact obtained for field samples.

Jan 1, 2008

By R. V. Ramani

"In Part 1 of this paper, published in the August 1995 issue of Natural Resources Forum, a review of several mining disasters around the world established the complex nature of their causation and their catastrophic effects. The involvement of human beings, either through acts of commission or omission, was highlighted. In Part 2, a discussion of the various approaches to disaster control, mostly as practised in the USA, is presented. A systems approach to disaster prevention incorporating elements of hazard identification, mine design, emergency response and post-emergency audit is presented.In the USA the role of government in the affairs of its citizens is continually growing. This role is intended to ensure an unimpeded pursuit of happiness and prosperity by the population and to curtail actions which are restrictive or harmful to the citizenry. The passage of a legislation is an indication that it has been decided through the established process that the activities covered by the legislation should receive appropriate consideration. The enactment of the Coal Mine Health and Safety Act of 1969 (The 1969 Coal Act), the Mine Safety and Health Amendment Act of 1977 (The 1977 Mine Act) and the Surface Mining Control and Reclamation Act of 1977 (The 1977 Surface Mining Act), was specifically intended to further the role of government in the health, safety and environmental affairs of the mineral industry.Currently, the federal government's responsibilities for mine safety and health are divided among three agencies: the Mine Safety and Health Administration (MSHA) in the US Department of Labor, the Bureau of Mines (USBM) in the US Department of the Interior and the National Institute for Occupational Safety and Health (NIOSH) in the Department of Health and Human Services (National Research Council, 1981). MSHA is responsible for issuing and enforcing mine safety and health regulations, for training miners and for responding to mine emergencies. The Bureau of Mines is responsible for conducting research on mine safety and on the technological means for reducing health and safety hazards in mines. NIOSH conducts research relating to miner health, and together with MSHA, tests and certifies devices used to detect hazardous materials in mines and protective equipment used by miners. NIOSH also plays a public health role in that its activities in mining include health hazard evalua¬tions, general mining surveillance as mandated by law and medical surveillance including coal miner X-ray and autopsy programmes. MSHA shares with the Bureau of Mines the responsibility for integrating R&D results into operational practice. MSHA implements R&D results either by incorporating them into its own operations or by rule making that requires new practices or equipment to be adopted by the mining industry. In many instances, the Bureau's R&D results have been adopted by the mining industry without rule making."

Dec 1, 1996

By Donald W. Mitchell

Studies were made in the Bureau of Mines Experimental coal mine to evaluate the effectiveness of a few extinguishing agents and techniques for controlling a fire on a simulated mining machine. The investigation showed that water containing an alkali-metal salt or a surface-active (wetting) agent was more effective than water alone. For close attack, fog applications was the most effective technique studied; high rates of agent application controlled the fire more quickly than low rates. The ability to control the fire increased as the distance of attack decreased. Dry powders controlled the fire when applied by shovel but not when applied airborne by rock-dust distributor or by hand fire extinguishers. Dry alkali-metal salt powders (potassium and sodium bicarbonates and sodium tetraborate) quenched the fire more readily than limestone dust. In each instance the finer powder, the greater its effectiveness. In an open ventilated entry, smoke and hot gases backed against the air currents. An airspeed of 230 feet per minute was required to permit approach to within 10 feet of the fire. At lower airspeeds, approach could be made by extending the brattice across the bottom two-thirds of the entry, by pushing the smoke ahead with water sprays, or by discharging dust from a rock-dust distributor. In a dead-end entry, the fire was approached to within 30 feet by coursing fresh air along an airtight line brattice; however, it was safer, easier, and less time-consuming to attack the fire from a fresh-air base 100 feet away with a solid stream or by high-expansion foam; the latter method was more effective.

Jan 1, 1961

By G. R. Peterson

The Bureau of Mines evaluated the potential supply of cobalt from known domestic resources, both as a primary product from some deposits and as a byproduct from others, and found that U.S. production could play an important role in meeting U.S. cobalt needs by the mid-1980's. This production would be of a relatively short duration, however, with production declining significantly before the year 2000. As part of the study, a tonnage-price relationship was developed indicating the quantity of cobalt that could be produced from known cobalt-bearing deposits at various primary commodity prices and at a 15-percent rate of return on the required capital investment. All capital and operating costs are calculated in August 1980 dollars, and commodity prices are based on August 1980 prices. Known U.S. cobalt-bearing deposits which represent the current U.S. cobalt reserve base contain some 310,800 metric tons of cobalt in slightly over 1 billion metric tons of demonstrated mineralized material. Approximately 37 percent of the cobalt contained in the reserve base is considered recoverable using existing technology. Of this quantity, some 87,000 metric tons of cobalt is economically recoverable assuming a cobalt price of $25 per pound, a copper price of $1 per pound, and a lead price of $0.40 per pound. Assuming that the cobalt price decreases to $15 per pound, keeping copper and lead prices constant, the quantity that is considered economically recoverable declines to some 45,700 metric tons. Domestic cobalt consumption in 1979 was 7,900 metric tons (17.4 million pounds). Currently, no primary cobalt is produced from domestic resources, and none has been produced since 1971.

Jan 1, 1981

By R. Hogg, T. F. Dumm

"Procedures for particle size analysis on respirable dust from coal mines have been evaluated. Using respirable dusts dispersed in a laboratory dust chamber, size distributions measured using cascade impactors have been compared with the results of a variety of laboratory sizing methods performed on samples collected on filters placed side-by-side with the impactors. The laboratory techniques included centrifugal sedimentation, laser diffraction/scattering and automatic particle counting. The general agreement among the various methods was very good, with systematic differences which can be attributed to the different definitions of size used. Simple conversion factors have been obtained which can be used to transform the laboratory data to equivalent aerodynamic sizes.Similar comparisons have been made on samples collected in underground coal mines. Again, the results are in quite good agreement although small discrepancies were observed in· some cases. These have been attributed to some degree of agglomeration in the airborne dust, leading to slightly coarser apparent distributions in the impactor samples INTRODUCTIONA primary goal of mine ventilation is the control of airborne dust, especially in the ""respirable"" size range, typically defined as finer than about 5 to 10 µm. It follows that determination of the amount and characteristics of the respirable dust is an important factor in evaluating the performance of ventilation systems. Particle size information on airborne dust in mines is commonly obtained by in- situ measurements using cascade impactors. However, these tend to be inconvenient for routine data collection and the alternative approach of collecting samples in the mine, on filters for example, and returning them to the laboratory for detailed analysis is very attractive. Questions have often been raised, on the other hand, as to the appropriateness of this approach. How well · do such laboratory methods describe the distribution of aerodynamic diameter of the airborne dust particles in the mine environment? The purpose of the work described in this paper was to evaluate some laboratory sizing methods and to compare the results of such measurements with the size data obtained by the direct, in-situ method."

Jan 1, 1989

By H. W. Wainwright

One phase of the research and development work on synthetic liquid fuels conducted by the Bureau of Mines at Morgantown, W. Va. in cooperation with West Virginia University deals with the purification of synthesis gas.2/ Most of the experimental studies on gas purification have been directed toward the removal of organic sulfur from gas, either catalytically or by adsorption with activated carbon. An important part of the purification program has been the development of suitable analytical methods for determining organic sulfur compounds. As the total sulfur content, organic and inorganic, of purified synthesis gas should not exceed 0.1 grain per 100 cubic feet, the need for accurate analytical methods is apparent. It is also apparent that such methods must be rapid if one wishes to evaluate various processes for removing sulfur from gas. The organic sulfur found in most gas produced from coal is usually present as carbon disulfide, carbon oxysulfide, methyl and ethyl mercaptans, and thiophene, with the exception of thiophene, the remaining organic sulfur compounds respond similarly to catalytic treatment and can be removed effectively. Not only does thiophene resist most catalytic treatment, but it poisons some catalysts, rendering them ineffective in removing the other forms of organic sulfur.

Jan 1, 1950

By Michael R. Yenchek

The U.S. Bureau of Mines investigated the performance of portable power cables under transient conditions. This research had a twofold purpose: (1) to define the thermal characteristics of electrically overloaded trailing cables, and (2) to conceptualize electrical protection for cables that allows maximum cable efficiency without diminishing electrical safety in underground mines. Several tasks were undertaken in support of these goals during the 3-year research effort. Overload tests ranging from 2 to 12 times rated ampacity were conducted in the Bureau's Mine Electrical Laboratory. Two thermal models of energized type G-GC trailing cables were constructed, one based on thermodynamic theory and the other using empirical data from previous Bureau load tests. The empirical model was then incorporated into an interactive computer program that can assist designers and approvers of mining machines in selecting the appropriate size trailing cable. This program can be the basis for a cable protection system that ensures that cables are not the source of fires, ignitions, burns, or explosions underground.

Jan 1, 2010

By Gerald W. Elger

To determine the feasibility of removing nonferrous metal impurities from automobile scrap by thermal treatment in a rotary kiln, the Bureau of Mines conducted four series of tests with synthetic scrap mixtures heated at various temperatures under oxidizing and reducing conditions. The treated scrap mixtures were melted in an electric-arc furnace and cast into small ingots for impurity evaluation. Analyses showed that the ingots were essentially free of residual metal impurities except for copper. Test data indicated that in an oxidizing atmosphere the percentage of copper removed increased with treatment temperature. Percent of copper removed in a reducing atmosphere was found not to be temperature dependent. A significant finding was that copper was embrittled under some of the operating conditions and was mechanically removed by fragmentation.

Jan 1, 1968

By Thomas J. Blalock

The volumetric determination of uranium according to the method of Sill and Peterson (6),3/ which uses cerate oxidimetry after the separation of interferences such as sulfides and cupferrates, has been used for some time by the Bureau of Mines and gives satisfactory results for many of the samples tested. However, in those instances where the uranium content did not exceed a few tenths of 1 percent and iron was present in the range of 10 to 40 percent (as Fe203),4/ the method was cumbersome and unreliable. The need for a more accurate procedure for the determination of small amounts of uranium in the presence of large amounts of iron, such as in shale or black sands, prompted this investigation. The Bureau desired that materials containing as little as 60 p.p.m. of uranium be assayed within reasonable limits of accuracy. One of the primary aims of this work has been to eliminate, as far as possible, the necessity for repeated cup ferron extractions.

Jan 1, 1960

By John A. Ruppert

1. It has been proposed that the addition of enough limestone to an open -hearth s lag to give a CaO-3P2O5 ratio of approximately 2-followed by SiO2 firing in an oxidizing atmosphere under the proper conditions of time and temperature will result in a clinker having a magnetic phase containing a preponderance of Mn, Fe, Al, and Mg as oxides and a nonmagnetic phase consisting for the most part of a phosphorus-containing dicalcium silicate. It has been postulated further that the metal oxide phase can be recovered by fine grinding and magnetic separation. These broad principles have been substantiated by numerous clinkering operations made in an electrically fired studio-type kiln, a batch rotary kiln, and a continuous rotary kiln and by magnetic separations made in a Davis -tube separator and a laboratory-size Jeffrey-Steffensen three -roll continuous separator. 2. Quenching the clinker after firing seems to improve its grindability. Microscopic examination of the ground clinker indicates .that the oxide phase grinds down at a somewhat faster rate than the silicate phase. 3. Very fine grinding is necessary to approach liberation, of the oxide phase from the silicate phase. Grinding to ininus-325-mesh, followed by magnetic separation, gave only a rougher concentrate, which had to be reground before final separation. 4. Although the manganese content of the final concentrate was higher, there was some evidence that manganese recovery was lower from a clinker made from a flush s lag than one made from a mixture of tap and flush slags. A possible explanation is that a clinker made from a mixture of slags has a higher iron content and hence is more magnetic and more easily separated.

Jan 1, 1952

By J. S. Berber

Bastnasite is a natural fluocarbonate of the cerium group and affords an abundant and high-grade source of the lighter rare-earth elements. As part of a broad research program in rare-earth element technology, the Federal Bureau of Mines directed extensive experimental work to separating and purifying the rare-earth elements in bastnasite. By the use of a combination of techniques--classical chemical, ion exchange, and solvent extraction--the processing of a bastnasite concentrate to obtain the individual rare-earth elements, or groups of elements, was accomplished. A bastnasite concentrate, containing about 60 percent rare-earth oxides, was sulfated with concentrated sulfuric acid to eliminate the carbon dioxide, fluorine, and silica. Calcination at 1,200° F. made the gangue matter insoluble, thus permitting the separation of the soluble rare-earth sulfates. Essentially 100 percent of the rare-earth elements were recovered by this procedure. Since the rare-earth sulfate solution contained only trace amounts of nonrare-earth elements, subsequent separation procedures were simplified.

Jan 1, 1960