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By C. P. Mishra

The Bureau of Mines investigated the availability of mercury from 22 deposits in market economy countries. The 15 significant deposits evaluated have demonstrated resources of approximately 25 million metric tons of ore containing 5.3 million flasks of mercury and account for more than 85 pct of the demonstrated resources for market economy countries. Using data gathered as part of its Minerals Availability Program, the Bureau determined the mercury production potential of each deposit. At a January 1984 mercury market price of $300 per flask, the deposits evaluated could economically produce an estimated 2.5 million flasks of mercury from six mines operating at the time of this study; no mercury is available at this price from nonproducing operations. At $600 per flask, approximately 4.5 million flasks of mercury are available. For production costs up to $300 per flask, operating mines could supply mercury at the current production rate of 114,000 flasks per year until 1988, when the amount of mercury available from these deposits would decrease. This decline could be offset by the development of resources currently reported at the identified level (17 million flasks) at much higher production costs.

Jan 1, 1985

By John J. Sammarco

The U.S. Bureau of Mines is conducting research into computer-assisted mining, which requires investigation of new techniques for development and application of computer-based technologies. Today's technology can require significant effort in software development, as has become evident in the early stages of this Bureau research. Technologies for software automation, such as computer-aided software engineering (CASE), are available. This report explores CASE, its general features, and its importance in software development. Information is presented to assist in selection and application of the variety of CASE tools and methods for automating various stages of software development. When evaluating CASE for use, it is important to examine tools that support an organization's existing methods of software development. Support for existing hardware platforms must also be examined. Merely selecting a "good" CASE tool does not insure success. Thorough evaluation of implementing CASE is also critical. Subjects to evaluate for CASE implementation include organization culture, support from management and end users, training resources, and pilot projects. Organizations that benefit the most from CASE evaluate CASE features with respect to their needs and they properly implement CASE.

Jan 1, 1990

A new horizontal borehole packer for use in coal beds has been developed. This packer utilizes a principal of operation which has not previously been used. The resulting packer is less costly to purchase, can be easily repaired in the field with inexpensive expendable parts. This report describes the development and testing of the new packer and the evaluation of commercially available packers.

Jan 1, 1971

By R. D. Groves

Laboratory research has demonstrated that high - grade copper powders can be produced under controlled conditions from cement copper products . The technique should enable small producers to prepare a directly marketable product by means other than smelting and electrolytic purification . A continuous drum- type precipitator was the preferred unit for producing fine - sized particles of cement copper that were further processed by chemical digestion in a copper sulfate solution , by reduction and sintering in a hydrogen atmosphere , and by grinding to a powder . The effects of variables related to all stages of the process were investigated . Treatment of leach solutions from three different sources resulted in copper powders containing 99.2 to 99.8 pct Cu , apparent densities of 1.97 to 2.25 grams per cu cm , good powder flow rates , and a size distribution of 54.9 to 60.1 pct minus 325 - mesh material .

Jan 1, 1964

By Gus Pantages, Bernard D. Blaustein, Charles Zahn, Irving Wender

Oils from coal hydrogenation have been examined at the Bureau of Mines to learn whether any centers of the optical activity reported in coal would survive catalytic hydrogenation at 450-525 ° C and about 8,000 psig pressure , and , if so , to obtain information about the nature of the active products . Oils from carbonization tars also were examined . Optical activity was found in the majority of the distillate fractions of the hydrogenation oils and in almost all distillates from the carbonization tars . No activity was observed in the tar - acid and tar - base fractions examined . Methods for isolating optically active concentrates included distillation through a packed column , liquid chromatography on silica gel , and adduction with urea . For the materials so processed , the optical activity segregated mainly in the paraffin - naphthenic and the hydroaromatic fractions . Although the specific compounds responsible for the optical activity were not isolated , experimental and spectrometric findings indicate that alkylsubstituted cycloalkane , cycloalkene , and hydroaromatic structures are most likely responsible for the optical activity of the concentrates . The optically active centers probably derived mainly from the steroids and terpenes in the biological materials that participated in the formation of coal .

Jan 1, 1964

By R. Vernon Helm

Four tables listing values for the various physical properties of those sulfur compounds most likely to occur in petroleum and petroleum products are given herein. The data necessary to bring the first compilation2/ in this subject up to date are given in table I -Revised and Additional Data, which includes boiling points, refractive indices, densities, and freezing points. Tables 11-, III, and IV are published for the first time and include refractive indices for the F, C, and G' lines of hydrogen and the helium D:3 line; surface tensions and viscosities, and refractivity intercepts, specific dispersions, specific refractions, and parachors. The need for information concerning the sulfur compounds in petroleum is becoming-more urgent because of the necessity of refining larger quantities of high-sulfur crude oil to meet the rising demand for petroleum products. For a number of years the Bureau of Mines has been engaged in research to make available more information concerning the properties of the sulfur compounds in petroleum. The petroleum industry has recognized the value of such studies, and as a result the American Petroleum Institute has established Research Project 48A to study sulfur compounds. The investigations under this Project are to be done in Bureau of Mines laboratories as a cooperative project in connection with the work already started.

Jan 1, 1949

By W. G. Messner

Pipelines for transporting crude oil and refined products in the United States totaled 189,982 miles on January 1, 1959. This mileage was less than a 1-percent increase from the 1956 total of 188,540 miles. During the three-year period (January 1956 - January 199), 14,886 miles of new pipe and 10,649 miles of secondhand pipe was laid. Pipe taken up in the same period was 24,093 miles. The facts regarding pipeline mileage were obtained by the Bureau of Mines from pipeline companies and information provided by the Interstate Commerce Commission. Crude-oil gathering lines, as of January 1959, were 40 percent of the United States pipeline mileage and totaled 75,182 miles, an increase of 1,656 miles during the three-year period. Crude-oil trunklines totaled 70,317 miles or 37 percent of the United States pipeline mileage, a decline of 8,277 miles from the 1956 total. Some of this loss is attributed to the converting of crude lines to refined products. Refined product lines in January 1959, totaled 44,483 or 23 percent of the United States mileage, an increase of 8,063 miles during the three-year period.

Jan 1, 1959

By Charles M. Mason

The Bureau of Mines evaluated equipment and procedures for drop-weight testing of explosive liquids as prescribed by Test 4) a widely used method. It was demonstrated that partial ignitions, originally designated as negative results, should be designated positives; it was also shown that wear or erosion of the sample cups and the type of mount used for the apparatus had important effects on the results. Relative sensitivity as measured by Test 4 was found to vary slightly with temperature. The Bureau also designed a fixed 2-kg weight and associated electromagnetic release, which subsequently were incorporated as standard in a revision of Test 4. The original concept that the test involves only adiabatic compression was found to be an oversimplification; an alternate mechanism for the initiation process is proposed in which due consideration is given to the effects of cavitation and microjets.

Jan 1, 1966

Low-cost housing, like automobiles, should be appraised in the light not merely of first cost but of upkeep as well. Even more important than the number of miles the family car will go on a gallon of gasoline is the number of days the family home can be kept comfortable on a ton of fuel. A furnace tender who tossed every third shovelful of coal into the ashcan would lose his job promptly, but the effect is the same when homes continue year after year to pour out precious heat through uninsulated roofs and walls, Greater economy in household heating means even more to the national economy than to the individual, especially now that we are preparing for defense. Our fuel resources, although large, should be conserved. If less fuel is used for civilian needs, augmented requirements for defense can be met without unduly increasing the number of men needed at the coal mines and oil ells or adding new producing units that might complicate ultimate readjustment to peacetime conditions when the emergency is past and over-expansion of many industries brings new problems if unnecessary demands for transportation facilities are reduced, public carriers will be able to haul more munitions, and manpower needed for national defense will be released; and by protecting workers from health hazards in their homes additional man-hours of productive effort will be gained. Moreover, reducing the running expenses of houses by proper heat insulation helps home owners to maintain payments on property, and by minimizing foreclosures helps to stabilize the financial structure of the country. In short, here is a situation where the interests of the individual and the Nation are identical and the greatest good for the greatest number is obtained without sacrifice to anyone.

Jan 1, 1941

By W. P. Diamond, J. R. Levine

The explosion hazard of methane-air mixtures has become an increasingly serious mine planning problem, and an advance assessment of methane gas potential can therefore be essential for a safe and economic mine development pro- gram. As part of its coal mine health and safety program, the Bureau of Mines has developed a simple, inexpensive test to measure the methane content of coal samples obtained from exploration cores. The gas content of coal per unit weight as determined by the direct method test can be used as a basis for a preliminary estimate of mine ventilation requirements, and to determine if degasification of the coalbed in advance of mining should be considered. Since the Bureau began measuring the gas content of coal samples in 1972, experience has led to equipment and procedural changes, the most significant of which has been the development of a ball mill for crushing the coal sample to release the residual gas at the end of the desorption test period. This revised procedure replaces the crushing box and graphical methods described in earlier Bureau publications. The results of 583 direct method tests are summarized in tabular form. These results include data on the gas content of 125 coalbeds in 15 States.

Jan 1, 1980

By Joan C. Biordi

A molecular beam-mass spectrometer-low pressure flat flame apparatus has been constructed for the purpose of examining the chemical microstructure of normal methane-oxygen-argon flames and those inhibited with Halon extinguishants. Details of construction and performance of this apparatus and of related flame temperature measurements are given. Particular attention is paid to the empirical characterization of the perturbation to the flame caused by the sampling probes. The composition profiles obtained for normal flames are compared to those of flames inhibited by CF3Br. In addition to the usual stable species (CH4, O2, CO, CO2, H2O, H2, and H2CO), the inhibitor, its products and intermediates associated with its reactions could be followed. In particular, hydrogen bromide, bromine atoms, hydrogen fluoride, and carbonyl fluoride were observed. The relatively rapid disappearance of inhibitor and early appearance of fluorinated reaction products suggest a short lifetime for the CF3 radical in this system. Observation of COF2 suggests that CF3Br is effective as an inhibitor, at least in part, by virtue of its interference with the oxygen containing species of the normal chain reaction. Profiles of the 17+ peak at low electron energy suggests that the hydroxyl radical may also be sampled, but the profiles obtained are not yet sufficiently accurate to determine the effect of inhibitor on this important flame radical.

Jan 1, 1973

By Albert L. Toenges

The fuel requirements for industrial and domestic consumers in New England, in normal times, are supplied almost entirely by fuel oil, anthracite, and bituminous coal. A shortage of these fuels occurred during the war. This shortage was caused by: (1) The diversion of oil to military uses; (2) the use of railroad and boat facilities that ordinarily would transport coal for the transportation of war material; (3) the inability of coal mines to apply the increased demand for coal which resulted from the conversion from oil to coal by domestic and industrial consumers; and (4) the increased demand of war industries for coal. Because of this Critical fuel situation, an investigation was made of possible sources of fuel nearer to points of consumption in New England.

Jan 1, 1948

By Dennis R. Kasper

This study evaluates selective environmental impacts of two distinct in situ mining techniques. In situ leaching of uranium, porphyry copper and native copper and in situ borehole (slurry) mining of uranium, sandstone, and pebble phosphate ores are the techniques and minerals investigated. The potential impacts onsite in the desert southwest (porphyry copper), Michigan (native copper), Texas and Wyoming (uranium), and Florida and North Carolina (phosphate) are addressed and discussed. The study emphasizes those impacts which are unique to in situ solution leaching and borehole slurry mining. Impacts which are characteristic of all construction projects in the general geographical areas investigated, such as socioeconomic effects on surrounding communities and site-specific impacts, such as rare and endangered species, are beyond the scope of this study. For each of the in situ processes and associated ores investigated, the physical and chemical characteristics of the systems are described, the toxicity of the leaching solutions are presented, and the potential impacts on the environment are developed.

Jan 1, 1979

The principal activities of the Bureau of Mines Explosives Research Center (now Safety Research Center) during fiscal year 1968 (July 1, 1967, to June 30, 1968) are reviewed in part 1. Part 2 presents short abstracts of the publications issued during this period in the Bureau series and in other media. Part 3 describes a short study on the thermal decomposition of RDX and HMX not destined for publication elsewhere. ACKNOWLEDGMENTS The Bureau gratefully acknowledges the support received through cooperative agreement in fiscal year 1968 from The Manufacturing Chemists Association.

Jan 1, 1970

By Edward G. Cunney

Track in underground bituminous coal mines was investigated and technology was taken from other industries in order to obtain information on conditions that impair the safety and efficiency of the track and to develop guidelines and useful information on the construction, inspection and maintenance of mine track. Volume 1 contains information on the investigations, observed track conditions, useful technology from railroads and other industries, derivations of track condition descriptors and limits, conclusions, and recommendations. Volume 2, Guidelines, contains recommended standards and practices for mine track. It includes the relation of track conditions to safe speeds; descriptions and limits for measurable track features, such as gage; descriptions of conditions for track components that are normally not measurable, such as subbase soils; construction requirements and techniques; inspection requirements and methods; and methods for managing and performing track maintenance work. It does not repeat the summary or? derivations. Volume 3, Inspection Handbook, summarizes recommended standards and procedures from Volume II and provides related information for ready reference by inspectors in the mines. As a research product to be used in mines, it does not repeat the summary, derivations or references.

Jan 1, 1977

By S. J. Hussey

Since the discovery in 1935 by Adams and Holmes that certain synthetic resins exhibit ion-exchange properties, many applications of the ion-exchange process have been made. There are two general types of ion-exchange resins. Cation exchange resins adsorb cations from solution, and these in turn may be replaced by other cations adsorbed under certain conditions. 'Anion exchange resins adsorb acids from solution, and the anion of the acid may then be replaced by other anions. It is reported, however, that certain anion exchange resins have a low capacity for anions of weak acids without the necessity of acid adsorption either directly or as an intermediate step. The adsorbed ions may then be removed from the resins by elution with an appropriate solution, and the resin is prepared for the next adsorption cycle by regeneration with another solution. Sometimes one solution, is used to simultaneously perform the functions of elution and regeneration. The first and probably the largest application is in the field of water purification. Other applications have been made in the production of high-quality foods for human consumption, in the recovery of valuable substances from solutions, in the separation or fractionation of electrolytes, and in several other fields, each of which has its specific applications, variations, and possibilities. Ion exchange resins also have been highly useful in perfecting techniques of laboratory analysis and research.4/, 5/, 6/

Jan 1, 1948

By Thomas C. Atchison

The purpose of this Bureau of Mines investigation was to measure the amplitude and shape of the strain pulse and the size of the crushed zone produced in a granite by different explosives and to determine how these quantities are related to the detonation properties of the explosives. The reflection theory of rock breakage has shown that the amplitude and shape of the strain pulse incident at a free surface determine the fragmentation and volume of rock broken. Determination of the properties of an explosive that control the characteristics of the strain pulse produced in the rock will help in evaluating explosives for use in blasting. The investigation showed the different explosives produced a twofold variation in the amplitude of the strain pulse but little variation in the shape of the pulse. The explosives also produced a twofold variation in the volume of the crushed zone, but differences among the explosives were more accurately determined by strain-amplitude measurements than by crushed-zone measurements. The peak amplitude of the strain pulse and the volume of the crushed zone correlated with the calculated detonation pressure of the explosive.

Jan 1, 1959

These tentative inspection standards have been prepared as a guide for the Federal inspection of the anthracite mines of the United States. The Federal Coal Mine Inspection Division is not a mining-law-enforcement

Jan 1, 1943

By Michael J. Friedel

The integrity of mine structures, such as the roofs, ribs, face and supporting pillars, is difficult to assess beyond the exposed surface. To mitigate potential rockfall hazards, the U.S. Bureau of Mines is assessing the usefulness of Rayleigh wave dispersion analysis to detect damage and stress-relieved zones in mine structures. Classical surface wave dispersion modeling is utilized at both laboratory and field scales in damaged and undamaged material to assess the integrity of a mine pillar and roof. To more fully exploit Rayleigh wave propagation characteristics, derivation of a novel dispersion parameter was conducted using a convolutional model. The development of a suitable Rayleigh wave dispersion system based on insight derived from forward modeling is presented. The application of inverse modeling for damage and stress assessment in the mine environment is also discussed.

Jan 1, 2010

By Robert C. Ellman

The Bureau of Mines investigated the factors that cause agglomeration of lignite by freezing during winter shipment and sought methods to avoid it. Tests showed that lignite may be freezeproofed by removal of the relatively small quantity of moisture involved in forming the frost crystals which cement particles together, or by controlling the crystal characteristics. Adding dried lignite fines proved to be an effective and superior freezeproofing method. Commercial adoption of this method has been successful.

Jan 1, 1965