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CESIUM metal production increased sharply in 1963. Domestic Production.--Cesium metal was produced by The Dow Chemical Co., Midland, Mich., MSA. Research Corp., Callery, Pa., and by Penn Rare Metals, Inc., Revere, Pa. American Potash & Chemical Corp., Trona, Calif., produced some combined cesium and rubidium. This company, Penn Rare Metals, Inc., and Rocky Mountain Research, Inc., Denver, Colo., produced various cesium compounds. Complete production data on cesium and rubidium and their compounds were not available for publication. Consumption and Uses.-Substantially more pollucite was consumed to produce cesium metal and compounds in 1963 than in 1962 but the overall consumption of pollucite continued to be small.

Jan 1, 1964

By Jr. Hardy, H. Warren Shen

"A study is presently underway by the authors to investigate the character of the bit-coal interaction during coal cutting and its influence on the size and shape distributions of the generated dust. An important aspect of this on-going project is the development of acoustic emission (AE) criteria which would make it possible to carry out remote monitoring of coal cutting operations. The on-going AE studies are fundamental in form and were undertaken to evaluate the general feasibility of AE monitoring techniques using simplified coal breakage and cutting procedures. The present paper will focus on the test facilities, experimental techniques, and results associated with linear, single-bit cutting. An AE-transducer, attached directly to the bit, detected AE signals during the cutting process.Experiments have been carried out on seven specimens of coal obtained from the USBM experimental mine at Bruceton, Pennsylvania. Three separate cuts were made for each of two bit angles (10 and 45 degrees) and two bit velocities (0.085 and 0.169 cm/sec), for a total of 12 separate cuts. Data associated with resulting particle size distribution and AE characteristics (major dominant frequency components) will be discussed. Data analysis has also been underway using a computer-based pattern recognition system known as ICEPAK (Intelligent Classifier Engineering Package). This program is able to evaluate over 100 features of an AE event and to make objective comparisons between AE signals associated with different loading or cutting parameters. The results to date show that AE generated during some of the test conditions can be recognized by ICEPAK with a recognition rate of 90% and higher while other conditions cannot at present be separated with a suitable recognition rate. Further analysis of the experimental data is presently underway.The reduction of the severity, and eventual elimination, of Coal Workers' Pneumoconiosis (CWP) depends on gaining fundamental understanding in a number of major areas. These include dust generation and entrainment, transportation, suppression, medical effects of dust, and possible treatment. At present a project is underway by the authors to investigate the character of the bit-coal interaction during coal cutting and its influence on the size and shape distributions of the generated dust. An important aspect of this on-going project is the development of acoustic emission (AE) criteria which would make it possible to carry out remote monitoring of coal cutting operations. Suitable on-line analysis of monitored AE data would allow engineers to evaluate factors such as shearer bit conditions and cutting efficiency, and to quantify the particle size and shape distribution of the generateddust. The on-going AE studies are fundamental in form and were undertaken to evaluate the general feasibility of AE monitoring techniques using simplified coal cutting procedures. To date experiments have been carried out on coal under uniaxial compression, linear single-bit cutting, and cutting using a laboratory-scale, single-bit shearer. A brief outline of the overall study has been presented in an earlier paper (Hardy, Shen and Kimble, 1995). This paper will consider the linear single-bit cutting studies in more detail.It is generally accepted today that most solids emit low-level seismic signals when they are stressed or deformed. In this paper this phenomenon will be referred to as acoustic emission (Hardy 1972, 1981, 1989). In essence, the measurement of AE activity in a field or laboratory structure is relatively simple. A suitable transducer is attached to the structure, the output of the transducer is connected to an associated monitoring system, and the AE signals occurring in the structure, due to internal or external stress, deformation, and failure are suitably acquired, pre¬processed and recorded."

Jan 1, 1998

By Rose L. Ballard

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of Volume I and in the State chapters of Volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is normally termed "mine output.? It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1985

By John H. Perry

The Bureau of Mines has developed several techniques for draining methane from coalbeds in advance of mining. Drilling long horizontal holes from an underground location is one such technique, which was successfully demonstrated in the Pittsburgh and Sunnyside Coalbeds. The same technique has now been applied in the Mary Lee Coal bed at Jim Walter Resources, Inc.'s No. 4 Mine, Brookwood, Ala., where two holes were drilled horizontally--one to a depth of 1,010 feet (308 m) and the other to 540 feet (165 m). The 1,010-foot (308-m) hole proved successful in degasifying a portion of the Mary Lee Coalbed. The hole drained methane for 1 year, during which time the initial gas flow of 200,000 ft3/d (5,663 m3/d) declined to 65,000 ft3/d (1,840 m3/d). Total gas production was 40 x 106 ft3 (1.1 x 106 m3). The gas was of commercial quality, with 98 pct methane and a heat rating of 990 Btu/ft3 (36.89 Mj/m3). The methane emissions from the faces of the mine section advancing into the degasified zone were reduced by 60 pet. The 540-foot (165-m) hole was terminated prematurely when it became impossible to maintain an open hole. Because of caving, very little gas was drained through this hole.

Jan 1, 1982

By Robert H. Lambeth

The Madison RARE II study area has four prospects with identified resources. These are listed in table 1 and are described in the following text. A high potential for Sillimanite exists at the Placer Creek occurrence (fig. 1, no. 7) and potential for phosphate rack in all areas underlain by the Phosphoria Formation. Some prospects exhibit minor potential for copper, lead, zinc, silver, and gold in the southern portion and very minor potential in the northern portion. Deposits in the northern end also have low potential for rare earth, asbestiform anthophyllite, or kyanite group minerals (including sillimanite).

Jan 1, 1982

By Terry J. Close

The Gates of the Mountains Wilderness study area is underlain by intrusive and sedimentary rocks, mainly limestone. No limestone has been produced from the study area; suitable material is more readily available elsewhere. Small amounts of gold, sapphires, and corundum were produced from a placer deposit along the banks of the Missouri River. The remaining gravel contains low mineral values. Other alluvial deposits along the Missouri River and Beaver Creek contain no identified economic resources other than sand and gravel. Some deposits could provide suitable construction material for local use.

Jan 1, 1984

By L. G. Marsh

The manufacture of lubricating oils from wax-bearing crude petroleums involves the removal and recovery of the paraffin wax contained in the lubricating distillates. During this process several intermediate products are formed, among them the mixture of waxes and oils known to the refiners as "foots oil." Because of its complex character, foots oil is little understood, and therefore methods of handling it in refineries are often inefficient. The Bureau of Mines is studying the manufacture of lubricating oils, and during the work has investigated the redistillation of foots oil. This report gives in brief the results of the investigation, and recommendations based upon it.

Jan 1, 1926

By T. E. Sterner

A laboratory investigation was conducted to determine the applicability of the thermal oil-recovery method as a means of increasing ultimate oil recovery in the Appalachian region. The primary objective was to establish self-sustained combustion in consolidated and unconsolidated sand test assemblies saturated with various amounts of Pennsylvania Grade crude oil and synthetic brine. Tests using blocks of sandstone were unsuccessful because of sealing problems and fracturing of the rock due to thermal stresses. A combustion wave of about 700° F was propagated through the sand-oil-water packs in the linear tube tests. The high air flux used resulted in high oil consumption and rapid movement of the combustion wave through the tubes. Analytical tests on the sand pack showed that sufficient fuel was deposited during the linear tube experiments for a self-sustained combustion wave.

Jan 1, 1967

By R. J. Shanley

This report presents a computer code that has been developed by the Bureau of Mines for isolating naturally occurring clusters of data plotted on the unit hemisphere and testing these clusters against a probability distribution which admits elliptical symmetry about its mean. A listing of the computer code is provided along with an example output illustrating the delineation and analysis of clusters in fracture orientations measured in a porphyry copper deposit.

Jan 1, 1975

By Harold R. Newman

The performance of Ecuador's mineral industry continued to be affected not only by depressed oil prices in recent years but also by natural disasters. In March 1987, Ecuador canceled foreign debt payments for the rest of the year and appealed for international aid because of a series of earth-quakes that destroyed villages and crippled the nation's oil industry. The earthquake destroyed a key section of the country's main oil pipeline and forced a halt to production and shipment of Ecuador's most important export product. Ecuador produces 240,000 barrels of oil per day and exports 144,000 barrels daily. Oil accounts for 60% of the nation's hard currency earnings. The Government of Ecuador asked the Organization of Petroleum Exporting Countries and other oil-producing countries to assume Ecuador's oil sales commitments. Ecuador agreed to pay the countries back in an equivalent amount of oil when it was able to resume exports.

Jan 1, 1989

By W. J. Fene, H. B. Humphrey, J. J. Forbes

"INTRODUCTION Loss of life from coal-mine explosions in the United States in 1949 was the lowest in any year since before 1870. Although fatality reports from coal nines before 1910 were incomplete,' the explosion fatalities from single disasters or individual States exceeded the 1949 total in each year as far back as 1870, when the records become fragmentary. Since 1890, the only other year in which fewer than 35 were killed was 1946, with a total of 32. Figure 1 shows the total yearly fatalities from explosions in all coal mines and those in anthracite mines alone since 1870. The fatalities in bituminous coal mines were not completely reported before 1910, but enough reports were issued by major coal-producing States to compile reasonably representative figures back to 1885. Any corrections would be additions to these totals.The reason for the moderate total of 46 explosion fatalities in 1948 and the low total of 8 killed in 1949 is thought to be the serious and careful attention devoted to elimination of coal-mine explosion hazards after the disastrous explosions in 1947. The standards now being observed generally with respect to ventilation, rock-dusting, and inspections for gas are better than those found earlier in even the mines having the best reputations for safety. Exceptions are still numerous, but they are fewer, month by month, because of the pressure of Federal and State inspections and a changing conception of the hazards that should not be permitted underground. The prevailing precautions have not eliminated all ignitions of gas or dust, but they have limited propagation to small explosions and have prevented serious loss of life.The number of ignitions (14) reported for the year was less than the average (24) for the 5 years 1944-48 and only half the average for the fiscal years 1929-44. Another favorable factor is that Bureau of Mines representatives were probably in closer contact with both small and large mines in nearly all coal-mining districts. Inspectors now assigned to individual districts are better able to keep informed on the happenings and the progress of safety in their districts. In 1948, one-fourth of the explosions were in mines that employed fewer than 10 men; this condition was duplicated in 1949."

Jul 1, 1950

By Michael G. Zabetakis

The process of ?gasfreeing? has been defined3/ as "* * * the removal of oil and vapors from tanks, pipelines, and compartments to render such spaces safe for the intended work," Generally, part or all of a vessel is gasfreed for one of several reasons: Periodic cleaning; tank inspection or repairs; shipyard overhaul or major repairs; or change of cargo, Curing the gas- freeing, flammable or explosive4/ mixtures (mixtures through which a flame can propagate after ignition by an open flame, heated object, electrical charge, or other means) may be produced. These mixtures create an explosion hazard, as the pressures produced after their ignition are often great enough to completely demolish the vessel and kill all those aboard, This paper outlines a study by the Federal Bureau of Mines of the gas explosion hazards likely to be encountered while gasfreeing a vessel compartment. To better understand these hazards it will first be necessary to review the language used in gas- explosions work. This language is considered in the following sections. Inert gases such as carbon dioxide, nitrogen, water vapor, and others can be used to decrease the range of combustible-vapor concentrations in which flammable mixtures are formed. Sufficient quantities of such gases can often be added to cause a mixture that originally was flamable to become nonflammable. Unfortunately, the use of water vapor in this application is complicated by the fact that elevated temperatures are required to keep the water in the vapor state. In practice, it may be difficult to maintain these elevated temperatures throughout the space (such as a cargo tank) to be inerted for any length of time. Accordingly, where other inert gases are not available, it may be desirable to gasfree a Lank by using heated air. To do this, the combustible vapors should be flushed as quickly as possible from the space to be gasfreed. In a properly designed system, large tanks were gasfreed with a littlee as 6 volumes of air per volume of tank capacity.

Jan 1, 1961

By Jr. Harty

Intensive work on the deoxidation of steel with manganese-silicon alloys by the U. S. Bureau of Mines has shown that the use of those alloys, which may be produced from our domestic manganese ores, would decrease the ferromanganese requirements of a very large tonnage of our steel by from 60 to 80 per cent and in some cases by 100 per cent. The open-hearth heats made with these alloys have been of excellent quality. The tonnage of our ferro-grade ores Which has been made available by the bureau's ore-dressing studies, combined with the products resulting from such processes as those developed by the bureau and by Bradley for Cuyuna ores, should easily fill our reduced ferromanganese requirements when manganese-silicon alloys and ordinary Spiegel are used in the way described in this report. There are no technical difficulties in the application of this practice, and any difficulties involved in its wide and immediate application would only be those arising from habituated ideas of the necessity of ferromanganese. General acceptance of this practice and development of the available sources of domestic ferro-grade material by already proven processes should make this country independent of foreign ores. This paper resents the results of work done under a cooperative agreement between the Pittsburgh Experiment Station of the United States Bureau of Mines and the Carnegie Institute of Technology, the Metallurgical Advisory Board, and the University of Pittsburgh, Pittsburgh, Pa.; between the Mississippi Valley Experiment Station of the United States Bureau of Mines and the Missouri School of Mines and Metallurgy, Rolla, Mo.; between the North Central Experiment Station of the United States Bureau of Mines and the University of Minnesota, Minneapolis, Minn.; and between the Rare and Precious Metals Experiment Station of the United States Bureau of Mines and the University of Nevada, Reno, Nev.

Jan 1, 1931

By C. H. Herty

Intensive work on the deoxidation of steel with manganese-silicon alloys by the U. S. Bureau of Mines has shown that the use of those alloys, which may be produced from our domestic manganese ores, would decrease the ferromanganese requirements of a very large tone of our steel by from 60 to 30 per cent and in some cases by 100 per cent. The open-hearth heats made with these alloys have been of excellent quality. The tonnage of our ferro-grade ores which has been made available by the bureau's ore-dressing studies, combined with the ,products resulting from such processes as those developed by the bureau and by Bradley for Cuyuna ores, should easily fill our reduced ferromanganese requirements Then manganese-silicon alloys and ordinary spiegel are used in the way described in this report. There are no technical difficulties in the application of this practice, and any difficulties involved in its wide and immediate application would only be those arising from habituated ideas of the necessity of ferromangenese. General acceptance of this practice and development of the available sources of domestic ferro-grade material by already proven processes should make this country independent of foreign ores.

Jan 1, 1931

By E. A. Johnson

As part of its effort to reduce the environmental impact associated with mining and metallurgical operations, the Bureau of Mines used a modified form of the Environmental Protection Agency's Extraction Procedure toxicity test on copper reverberatory slags that contained low, medium, and high levels of the impurity elements As, Pb, Sb, Bi, and Zn. All tests resulted in extracts that did not exceed those limits published in the May 19, 1980, Federal Register; there-fore, these solid wastes were designated as nonhazardous for most landfill disposal situations. However, arsenic and lead levels disturbingly close to the allowable limits--and even higher levels of copper and zinc, for which there are no established limits--leached from the high-impurity-element granulated slags. These slags should be handled in such a way so as to minimize the possibility of water contamination. One baghouse dust was tested according to the EPA procedure and found to exceed the extract limits by a factor of 10. This solid waste may be considered hazardous.

Jan 1, 1982

By Yael Miron

ANFO blasting agents may undergo an exothermic reaction when they contact warm ore bodies that contain pyrite and its weathering products. The reaction is very fast at temperatures above 80° C. Urea, when present in sufficient amounts, inhibits this reaction at temperatures below 180° C. But urea-ammonium nitrate mixtures are very hygroscopic and, in certain climates, may be difficult to handle in the field. Reaction-inhibiting characteristics of three compounds were reported by the Bureau of Mines in 1979. Recently, the Bureau investigated the reaction-inhibiting qualities of five additional compounds. Mixtures of ANFO, pyrite, weathering product, and prospective inhibitors were slowly heated, under conditions simulating a hot borehole, to determine prospective inhibitor capability at temperatures up to ~175° C. Small-scale thermal tests of the same mixtures were used for verification and clarification of results. Two organic compounds, phthalimide and xanthine, similar in structure to urea, failed to inhibit the reaction. Zinc oxide and calcium carbonate were found inferior to urea, though zinc oxide raised the onset of reaction from 80° C to about 140° C. Only magnesium oxide was found to be similar to urea in its inhibitory ability at temperatures below 175° C. Based on results from analysis of quenched residues, the use of more than 5 wt-pct magnesium oxide is recommended.

Jan 1, 1982

By E. G. Valdez

The Federal Bureau of Mines, in cooperation with Ford Motor Co., investigated the recovery of polyurethane foam and other assorted plastics from the nonmagnetic reject of automobile shredders. Preliminary studies were con-ducted on a 1957 hulk augmented with additional foam and assorted plastics. The proposed flowsheet developed by the Bureau from the preliminary studies consists of a combination of screening, water classification, and gravity separation. The process was then tested on reject from two shredded 1972 cars. All of the foam and between 52 and 70 pct of the assorted plastics were recovered. The composition of the reclaimed foam concentrates ranged from 46 to 66 pct foam; the concentrates were hydrolyzed in laboratory tests by Ford Motor Co. to produce a reusable liquid mixture of polyether glycol monomers and toluene diamine.

Jan 1, 1975

By Robert Blickensderfer

Equipment and procedure for the continuous roll bonding of metal strips are described. The reels, mill rolls, and furnace were located within a vacuum chamber capable of operation at a residual gas pressure of 1 x 10-4 to 1 x 10-5 torr. Several metals were successfully clad at rolling temperatures of 930° to 1,050° C in lengths up to 120 ft. The bimetals that were clad included stainless steel to carbon steel, molybdenum and nickel to stainless steel and carbon steel, and titanium to carbon steel. Bend tests of bond integrity are described, and microstructures of the interfaces are presented. The amounts of brittle intermetallic phases formed at the interface are minimized by this cladding method.

Jan 1, 1980

By Kathleen Madland Kowalski

In recent years the issue of human stress response in emergency workers has begun to receive attention. This paper presents a rationale for considering human stress as a significant factor in the management of emergencies It discusses the concept of stress, Critical Incident Stress in emergency responders, and intro¬duces the Critical Incident Stress Debriefing (CISD) process. It is suggested that in a disaster, the CISD process can improve the effectiveness of response teams on site, their turnaround time on site, and post disaster time off the job. This paper, prepared by a US Bureau of Mines research psychologist, offers some ideas to the mining industry in general, mine rescue trainers and more universally, to those responsible for developing emergency management plans.

Aug 1, 1998

By C. H. Elder, Fred N. Kissell, S. D. Maksimovic

The Bureau of Mines evaluated the hydraulic stimulation of a gob-degasification borehole to determine if this procedure would aid in degasifying a longwall panel. The stimulated borehole did not degasify the longwall panel as expected either before or after mining of the panel started. It reduced the underground methane emission only 11 pct, considerably less than the reductions effected by two unstimulated boreholes in the same panel. Some probable reasons for the reduced methane flow from the hydraulically stimulated borehole are very low reservoir gas pressure, location of hydraulically stimulated zones within the grouted casing, a casing break caused by lateral shifting, possible vertical movement of rock strata during caving, grouting of a 4-inch pipe blocking three stimulated zones, plasticity of shales, and possible hole damage by swelling of water-sensitive minerals. The borehole was also located between two second-mined areas, which may have allowed partial degasification of the overburden and the coalbed in advance of mining. Finally, a period of 3 months is probably not long enough for the borehole to degasify the overburden before mining.

Jan 1, 1977