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By K. E. Stanfield

Asphalts from. Wyoming "black oils" are being studied at the Petroleum Experiment Station of the Bureau of Mines at Laramie, Wyo., in cooperation with the University of Wyoming. These black oils are characterized by their high-asphalt, high-sulphur, and low-gasoline content and are difficult to refine by present methods into high-octane motor fuels, burning oils, and lubricants. Accordingly, their principal use, at present, is for the manufacture of road oil and asphalt. The present production of black oil could be increased to meet a greater demand. During 1937 the daily production of these crude oils in Wyoming was slightly over 13,000 barrels, while the estimated potential production from existing wells was 56,000 barrels.

Jan 1, 1939

By Charles L. Harness

Fifty years ago, the belief that "fillers" were added to paints for the sole purpose of diluting and cheapening the pigment may have been justified; but paint technology has made tremendous progress since that time, and today both the manufacturer and the consumer know that the judicious use of fillers may add desirable properties to a paint that cannot be introduced in any other way. A growing respect for these accessory materials has led to the use of the more euphemistic term "extender." The names "extender" and "filler" are to a considerable degree synonymous. The newer term, "extender," is adopted in this paper, though it is actually no more descriptive than the older name. Stewart's3/ definition of extender is: "A cheap pigment, usually of an inert type, used to extend or increase the bulk of a paint, thus reducing its unit cost. Extenders are also used to adjust the consistency of a paint and to let down colored pigments of great tinting strength. The use of an extender in a paint does not necessarily mean the resultant product will be inferior. In fact, extenders sometimes, improve -certain characteristics of a film." All extenders are not cheap, as, for example, wet-ground mica and diatomite. Research in the, use of extenders (also sometimes called "inerts") has been one of the host active branches of study in the paint field; and many thousands of dollars have been spent in establishing the physical and chemical characteristics required of various natural mineral extenders for numerous paint formulas

Jan 1, 1943

By M. J. Pazuchanics

This U.S. Bureau of Mines report presents results from an ongoing investigation of the use of adaptive signal discriminating methods to distinguish between cutting coal and cutting mine rock. Bit-cutting forces and tool vibration were measured in the laboratory as a linear-cutting apparatus (LCA) made constant-depth cuts in coal, sandstone, and shale test specimens. A portion of the collected data has been analyzed and some preliminary results are given here. The influence of data bandwidth, data window size, number of signal features, and voting among classifiers on classification performance are noted. Results to date, based on ideal-cutting conditions and simple geologic materials, indicate that of the four classifiers tested there appears to be no single best classifier. Usually, classification accuracy showed slight improvement as the number of features considered for classification increased. The highest classification accuracies were achieved when voting was conducted among classifiers followed by voting among force components.

Jan 1, 1991

By Hylton R. Brown

Although extensive research has been carried on to determine the factors affecting the explosibility of carbonaceous dusts, as much has been published on coal-dust and grain-dust explosions recent reports of loss of life and property in explosions if metal dusts emphasize the lack of information on the extent of the dust-explosion hazard in plants manufacturing or handling; aluminum, magnesium, or zinc powder, as well as other metal or mineral dusts. Early investigators believed that only the carbonaceous dusts formed explosive mixtures with air, and it was not until near the beginning of the present century that the explosibility of certain metal and mineral dusts was recognized generally. In his book, entitled "Fire and Explosion Risks," published in 1904, Von Schwartz called attention to such hazards. Many vague references to metallic-dust explosions are found in the literature, such as "a severe explosion of aluminum dust occurred in the Middle West several years ago," but very little information seems to be available on the extent of the hazard, the number of explosions, or the amount of loss caused by explosions in pants handling metallic or mineral dusts or powders other than those of a carbonaceous nature. A search of the records of insurance companies, rating bureaus, fire underwriters,and fire-protection associations as well as the files and records of Government agencies has been made to obtain authentic data on explosion losses. To indicate the extent of the hazard a summary of laboratory tests covering the explosibility of certain metal dusts, with brief reference to their uses and Methods of manufacture, and the data compiled from the information available on losses are presented in this publication.

Jan 1, 1941

By R. D. Leitch

[The accepted theory of acid formation in coal mines with the subsequent appearance of the acid in coal-mine drainage, is oxidation of iron pyrite and subsequent solution and hydrolysis of the iron sulphate formed. It has also been found that 5 gobbed sections and worked-out areas, where there is usually an abundance of iron pyrite-bearing, materials in contact with air, are the sections that make the most important contribution to the quantity of acid drainage. It would thus seem obvious that if oxygen can be kept out of contact with tae acid-forming materials in tie- sections mentioned the amount of acid in coal-mine drainage could be reduced markedly and corrosion problems with mine pumping equipment and general stream pollution mitigated thereby. Although the efficiency of the suggested remedy as been borne out by laboratory experiments6, it has appeared desirable to substantiate the laboratory work by field observations in so far as pertinent data are available. It has been difficult to learn of mines or sections of mines about to be sealed, whereby an actual comparison of the drainage before and after sealing can be made. In view of that difficulty it has been necessary to devote attention to a comparison of the character of the water from areas already sealed with that from open but otherwise comparable sections of the sane mine. Previous cork has shown that the acidity of drainage in different parts of the same mine may vary, but if it can be shown also that the water from sealed areas is with but fen exceptions less acid than the otherwise similar open sections of tae same mine, the laboratory finding will be supported in a practical gray. This report presents some of the evidence that has been obtained.]

Jan 1, 1930

By Bruce I. Thomas

The Fairbanks mining district forms an arc 40 miles long and 8 miles wide on the north side of the Tanana Valley in central Alaska. This is a region of broad valleys and rounded hills that range in elevation from 600 to 2,600 feet Lode-gold production started in 1910 and has continued sporadically to the present, but the largest single mine produced only 40 tons per 24-hour day. Total recorded lode-gold production of the district is 241,000 fine troy ounces of gold from ore that averaged 1.32 fine ounces per ton. The ore was mined chiefly from narrow veins and veinlets alined along anticlinal folds at Ester Dome and the Pedro Dome-Cleary area. The only proven reserves are reported to be at the Ryan Lode at Ester Dome and at the Keystone Mines, Inc., holdings in the Pedro Dome-Cleary area. An inferred lode-gold resource for the district of approximately 4,000,000 ounces is considered to indicate only the order of magnitude of the lode-gold potential because of the absence of detailed data needed to evaluate the numerous deposits.

Jan 1, 1973

By G. S. Rice

[This paper describes preliminary tests at the Bureau's Experimental Mine to determine, under conditions that may prevail ira bituminous coal-mine heading, how small a quantity of fire damp may bring coal-dust into suspension and ignite to it. The results show that the explosion of as little as 150 cubic feet of an explosive mixture of gas and air containing 9 per cent natural gas may start a disastrous explosion Of coal-dust. This is a very small volume, of gas, to cause such a result. Let us suppose that this amount of exclusive mixture, was at the face of an entry which was 10 feet wide and the face was overcut to a depth of 6 foot and an upper layer of coal 2 1/2 feet thick had been removed, the recess so made would save a volume of 150 cubic feet. Furthermore, only 13 cubic feet of pure methane is needed in this volume to produce this 9 per cent explosive mixture.]

Jan 1, 1930

By G. S. Rice

This paper describes preliminary tests at the Bureau's Experimental Mine to determine, under conditions that may prevail in a bituminous coal-mine heading, how small a quantity of fire damp may bring coal-dust into suspension and ignite it. The results show that the explosion of as little as 150 cubic feet of an explosive mixture of gas and air containing 9 per cent natural gas may start a disastrous explosion of coal-dust. This is a very small volume, of gas, to cause such a result. Let us suppose that this amount of explosive mixture, as at the face of an entry which was 10 feet wide and the face was overcut to a depth of 6 feet and an upper layer of coal 2.5 feet thick had been removed, the recess so made would have a volume of 150 cubic feet. Furthermore, only 13 cubic feet of pure methane is needed in thin volume to produce this 9 per cent explosive mixture.

Jan 1, 1930

By John W. Frey

This paper is one of a series of digests of foreign mining legislation and court decisions prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of cw Zealand, as prepared by Dr. Frey the best available information in Washington, has been slightly amplified in accordance with suggestions transmitted through the courtesy of the Department of State by W. L. Lowrie, Consul General at Wellington.

Oct 1, 1929

By K. E. Stanfield

Asphalts from. Wyoming "black oils" are being studied at the Petroleum Experiment Station of the Bureau of Mines at Laramie, Wyo., in cooperation with the University of Wyoming. These black oils are characterized by their high-asphalt, high-sulphur, and low-gasoline content and are difficult to refine by present methods into high-octane motor fuels, burning oils, and lubricants. Accordingly, their principal use, at present, is for the manufacture of road oil and asphalt. The present production of black oil could be increased to meet a greater demand. During 1937 the daily production of these crude oils in Wyoming was slightly over 13,000 barrels, while, the estimated potential production from existing wells was 56,000 barrels.

Jan 1, 1939

By F. S. Crawford

Mining companies are usually held responsible for accidents occurring to the public around their operations . Safeguards are provided by progressive mining companies to prevent the public from getting into danger from wandering unattended about the properties . At abandoned operations , where little or no supervision can be maintained , persons are often injured through the negligence of the operator in leaving the property in unsafe condition . After a mine is abandoned or a lease is given up by a mining company , the responsibility for the safety of the property rests sometimes with the State to which the property ownership reverts or with the owner of the land ; either is usually quite unwilling to spend any money to remedy unsafe conditions due to the carelessness of the mining company . The land owner or the State , or both , should see that the work of leaving safe conditions behind is done by the operator before he abandons the mine or gives up the lease . Some of the worst hazards to the public at abandoned mines are from old test pits , abandoned shafts or tunnels , open pits , caved ground , and bodies of water in abandoned open pits . Hazards exist from some of these sources during the active operation of a mining property as well . In the early stages of mining operations test shafts are often sunk from 50 to 100 feet deep through the more or less loose material overlying bed rock . When these shafts are left unprotected , they are a serious danger for many years to come . In the course of time they become largely concealed by brush and grass , and thus are a deadfall to anyone who might happen to step into them . This condition will hold true for any part of the country, but to a much less degree where it is not necessary to sink through a great amount of cover . Many progressive operating companies have adopted the practice of filling in test pits after securing the information desired . Some nonresident landowners and exploration companies , however , have left such pits open , and it is extremely difficult for the mine inspector to get into communication with the owner . Frequently operating companies voluntarily fill test pits on adjacent property not

Jul 1, 1930

By C. J. Johnson, C. J. Bise

"IntroductionCoal extraction by continuous miners (CM) is currently the most common underground method in the US industry and accounts for slightly more than two-thirds of the nation· s deep mining production (National Coal Association, 1987). Even if longwall mining should become more commonplace, it can proceed only af1er ventilation and access entries have been driven by CMs. Since an area of concern continues to be the effects of the dust generated on the health of mineworkers, this paper discusses the relationship between the elemental composition of mining-generated airborne dust sampled from the immediate ventilation return of a CM and laboratory-generated dust derived from channel samples taken from the mines.There are several potential contributions of this type of study to the coal mining industry. First after more fundamental knowledge of the causes of Coal Worker's Pneumoconiosis (CWP) is learned, the laboratory-generated respirable dust could be used to identify a potentially hazardous coal seam. Also, this study could possibly aid in understanding the fundamental causes of CWP by producing mining-simulated samples of coal dust that could be used in epidemiological studies.Further, assuming that there is no difference in the elemental composition of a drill-core sample and a channel sample from the same location a mining company could predict anew mine's respirable dust elemental composition In the immediate ventilation return by using exploratory drill core samples of the roof ,coal, and floor rock to prepare the laboratory dust. Ventilation engineers could then use engineering design and control measures during premine planning to reduce the incidence and severity of CWP by better ventilating the potentially hazardous coal seam. If this proper planning prevented any future changes to the ventilation equipment and mine design, much time and money could be saved.Scope of workTo investigate the variability of the chemical characteristics of respirable dust, airborne dust samples from eight underground coal mines located in the eastern and mid western United States were collected with eight-stage Sierra Model 298 Marple cascade impactors, as well as 25 channel samples of mined material. Each channel sample was removed from the middle of the coal face before mining occurred. Sampling of the mining-generated dust was conducted by Lee ( 1986) by sampling the entire working sections, primarily for characterization purposes, to obtain information on the locational variability of dust characteristics. Research performed for this study used the elemental analyses of the mining-generated dusts he sampled in the immediate ventilation returns of CMs."

Jan 1, 1989

By H. O. McDonald

Solutions containing Cr6+ and sulfuric acid are used in a number of surface-finishing operations. Substantial quantities of chromium and copper are lost and pollution problems are created when the spent solutions are discarded. To minimize the undesirable environmental effects while improving secondary resource recovery technology, the Bureau of Mines is conducting research to detoxify and recover metals from these solutions. Spent etchants are treated to remove copper and reduce Cr6+ to Cr 3+ in an electrolytic cell. The anodes and cathodes are granulated coke. The spent solution is continuously pumped through the electrodes. Hexavalent chromium is reduced to trivalent chromium, and copper is recovered at the cathode. Reoxidation of Cr3+ at the anode was not observed. The removal and recovery of copper reduction of Cr6+ lessen chemical demand and increase efficiency in waste in treatment operations associated with the use of these solutions.

Jan 1, 1980

By Dennis A. Long

Slip and fall accidents are a major cause of lost-time injuries associated with large mobile equipment in surface mines. An evaluation of the safety hazards associated with getting on and off large surface mining vehicles showed that most of the accidents occur at the point where personnel attempt to mount or dismount the machine at ground level. The major hazardous design conditions were identified as excessively flexible supports for lower steps or rungs, inappropriate ground-level-to-first-step distances, poor step designs, access designs that use vehicle components as steps or walkways, and inadequate hand- rail and guardrail designs, Additional hazards are introduced by the lack of proper maintenance of ladder hardware and the work practices of operators in carrying articles while mounting and dismounting the vehicle. This Bureau of Mines report describes the design and in-mine testing of improved access system for large mobile mining equipment.

Jan 1, 1984

By C. W. Owings

Recent recommendations of the Bureau of Mines regarding, rock dusting to prevent dust explosions in coal mines have been issued as Mine Safety Board Decision 32 and printed as Information Circular 7109.5/ The last paragraph on page 2 of I. C. 7109 states: After a mine or any part of a mine has been rock-dusted, samples of dust for analysis should be taken from the floor, ribs, roof, and timbers at such intervals of time as will give apple warning of need far redusting in order to maintain the required minimum percentage of incombustible in the mine dust. Details of the methods of sampling and analysis are given in Bureau of Mines Information Circular 7113.

Jan 1, 1940

By Alan R. Buehler

In 1986, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied part of the 256,430-acre Alvord Desert and part of the 22,240-acre East Alvord Wilderness Study Area (OR-002-074 and OR-002-073A, respectively), in order to evaluate their identified mineral resources. The study areas are located in Harney and Malheur Counties, OR, about 25 mi northeast of the small village of Fields. There are no mines, prospects, or identified mineral resources inside the study areas. Basalt flows within the study areas contain chalcedony-lined vugs and banded agate which may be of interest to rock hounds. An ignimbrite flow contains perlitic material, but crystalline contaminants make it unsuitable for commercial uses. Lacustrine (lake) sediments contain diatomite and clays, and evaporite crusts contain boron too low grade to profitably mine. Small quantities of common opal and petrified wood occur which might be of possible interest to rock hounds. Some of the petrified wood is black, free of fractures, and polishes well; it may be suitable as backing material for soft, thin, and brittle gemstones, such as precious opal. The lacustrine sediments also contain black, fetid layers which have above background, but economically insignificant concentrations of zinc, cobalt, nickel, barium, iron, manganese, aluminum, and potassium. Large quantities of fine-grained dune sands within the study areas are too far from markets for economic consideration. Ephemeral streams in the study areas contain small amounts of placer gold of no economic interest. The western portions of both study areas are reported to have moderate favorability for occurrences of natural gas, and both study areas are reported to have high favorability for the occurrence of geothermal resources. As of December 1986, oil and gas leases covered 3,100 acres in the study areas.

Jan 1, 1987

By H. R. Batchelder

Much information on oxygen production and the manufacture of synthetic liquid fuels has been published during the past several years. From time to tine the investment and operating cost of oxygen plants of various sizes has been estimated. Surveys have been made so that the various processes by which oxygen is produced commercially might be compared. The gas-making processes in which oxygen is employed, which wore used in Germany during the war, have been described in T.O.M. reels, and this information has been published. Descriptions of pilot-scale or proposed commercial plants for the production of synthesis gas or hydrogen and their conversion to synthetic liquid fuels also have been published. In general, each of these publications has dealt with a particular phase of the over-all problem. The present paper will discuss the relationship between these phases: The factors that affect oxygen manufacture and costs, the methods for the use of oxygen and for the production of synthetic liquid fuels, and, to some extent, the economic factors that must be considered.

Jan 1, 1951

By L. C. IlsLey

So many subjects are covered in State mine-safety regulations that any attempt to compare different State laws in their entirety would be futile. On the other hand, if one selects a single phase or branch of safety work, such a comparison may prove profitable. The subject selected for study in this paper is limited to legislation or regulations dealing specifically with safeguarding (electric) motored equipment used in gassy mines. T When one reads glowing accounts of the safety activities being carried on here and there it is easy to believe that everything which is right and proper is being done to safeguard the mine.workers; but, when one takes time to look into the weakness of many State regulations, it is evident that there is still room for improvement. Undoubtedly it would have been much better for the safety of mines if electrical equipment had been introduced into mines 50 years earlier. If electricity had been in general use when the first mine regulations were pre- pared, those formulating the rules would have covered this hazard along with other hazards, but as electricity came in at a later period, safe mine legisla- tion regarding it has been woefully neglected. Today the United States in general is far behind most other coal-producing nations in the provision of adequate safety rules or laws for the installation and maintenance of electrical equipment and wiring. Returning to the subject of our study, approximately 30 of the 48 States mine coal. More than 20 of these States' produce coal in large quantities. How- ever, of the 30 States only four, 3 Pennsylvania, Utah, Washington, and West Virginia, have laws which specially call for the use of explosion-proof types

Jan 1, 1929

By E. J. Gleim

To make a thorough survey of a coal mine in order to eliminate hazards, the competent safety engineer must be familiar with mere than one branch of engineering. It is essential that he know the properties of mine gases and the methods of detecting them, as well as hew to prevent dangerous as accumulations. It is also essential that he understand the action of overlying strata when the coal is removed, and the proper methods of protection by timbering or other suitable means of support. He must know the value of protective clothing in reducing injuries and mast be informed as to the correct handling and use of explosives to avoid premature blasts, misfires, and ether failures in blasting practice. He must understand hew to operate locomotives and cutting, loading, and various other types of machines to be able to recommend effective safeguards for protecting the men who use them in addition to being informed as 'to these and many ether activities connected with the mining of coal, he must net overlook electrical engineering if he wishes to combat the fire, shook, and ignition hazards attendant upon the use of electrical machinery and circuits in and around the mine intelligently. There are many points relating to safely in the selection, maintenance, and use of electrical circuits and equipment that are perfectly obvious to the electrical engineer but perhaps are not se evident to those not trained in this particular branch of engineering. Engineers of the U.S. Bureau of Mines who have made a special laboratory study of electricity as related to safety in minus haw e also made inspections of electrical installations at a large number of bituminous mines. These inspections have revealed practices and conditions that not only do not contribute to safety but that add nothing to efficiency and economy in the operation of the mine.

Jan 1, 1936

By D. E. Emerson, C. G. Kirkland, E. M. Frost

An apparatus has been developed for determining the helium content of gases containing 40 percent or more helium . It utilizes activated coconut charcoal at liquid nitrogen temperatures to adsorb constituents other than helium in the mixture . Series of analyses have been run where the mean deviation was less than 0.05 percent helium . Twenty or more analyses can be made in an 8- hour day .

Jan 1, 1964