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By Charles Zahn

Direct mass spectrometric determination of alcohols in the presence of hydrocarbons has not been possible because of the similarity of hydrocarbon and alcohol mass spectra. Experiments have demonstrated that by converting the alcohols to their trimethylsilyl derivatives, characteristic mass spectra are obtained free of interference from hydrocarbon ion fragmentation. Hexa- methyldisilazane is the reagent selected for the conversion, An improved method of preparing the reagent is given, Mass spectrometric determination of alcohols as trimethylsilyl ethers now is not only possible without prior separation from other materials, but the range of the room-temperature mass spectrometer is also extended to include the C10 alcohol region. Water does not interfere because it is converted to hexamethyldisiloxane, which has its own distinctive mass spectral peak, Experience indicates that other compounds such as glycols, amines, and phenols probably could also be determined by mass spectrometry of their trimethylsilyl ethers. Studies on the similar detemination of phenols in coal oils have been started, When mass spectrometry is not available, gas-liquid chromatography of alcohols before and after their conversion to the trimethylsilyl derivatives probably could be performed. The preparation and properties of the trimethylsilyl derivatives of 23 alcohols, 2 glycols, 3 amines, and 1 mercaptan are detailed. INRODUCTION During investigations by the Bureau of Mines at the Pittsburgh Coal Research Center relative to the development of Fischer-Tropsch processes, complications were encountered in the mass spectrometric analysis of alcohols in hydrocarbon oils. The fragmentation peaks of the alcohols and the hydrocarbons were so similar that an accurate analysis was not possible, Since involved separation techniques are necessary to isolate alcohols from hydro-carbons for separate determinations, efforts were turned to the search for a

Jan 1, 1962

By J. L. Konchesky

The technical feasibility of gasifying powdered, noncoking, low-rank coal with steam in an externally heated tube has been demonstrated. The tube, 112 ft. of alloy-steel tubing shaped into a helix, served as an electrical conductor of electricity used for heating. The effects of the following variables were studied: Residence time of coal in reactor, average reaction temperature, steam concentration, and rank or geologic age of coal. Reaction pressure was maintained in the range 19-26 p.s.i.a. High carbon conversions and large yields of synthesis gas were obtained with low-rank coal. In one test, for example, about 88 pct. of the carbon in a subbituminous C coal was gasified at 1,910* F. with a residence time of 1 sec. The gas contained 58 pct. H2, 19 COD 15 CO, and 3 CH4; the yield was 30 cu. ft. (at 32' F. and 14.7 p.s.i.) of synthesis gas (CO + H2) per pound of dry coal.

Jan 1, 1960

Many USBM research and information products are available through the systems or formats listed below: Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219 3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button o your fax machine. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. CD-ROM: This USBM disk is updated quarterly and sold by GPO's Superintendent of Documents. For information on the latest product, please contact Rodger Wedgeworth, 202/501-9557. Internet/World Wide Web: Text and graphics. Access via PC-based browsing software such as Netscape or Mosaic. Universal Resource Locator (URL) is: http:/www.usbm.gov Internet/Gopher Server Text and tables only. Using Gopher client software, access via port 70 as follows: gopher.usbm.gov Internet System Administrator: webmaster@usbm.gov (or contact your local System Administrator).

Jan 1, 1995

By A. C. Johnson

This circular is one of a series published by the Bureau of Mines describing mining and beneficiation methods and costs at various mining operations throughout the United States. Inclusion of the Abbott mine in this series is of particular interest, as the complex geology and the character of the deposits make their exploitation a unique operation. The mine operates on a high-cost, comparatively small-scale basis, and only the persistence of an aggressive management has enabled it to maintain its rank among the major mercury producers of California. Rising costs and decreasing metal prices, which continuously threaten the low profit margin, are reflected in increased efficiency of operation. This report summarizes past operations and describes, in detail, the geology and ore deposits; exploration and mining methods; and furnacing and condensing operations. It covers the entire operation from initial exploration to the actual production of mercury. Comparative production costs for 1944 and 1958 are of special interest.

Jan 1, 1962

By H. M. Lawrence

"The land-pebble district, the larger of the two producing areas of Florida, is situated in Polk County and in the eastern part of Hillsborough County. About 80 per cent at the phosphate rock produced in the United States in recent years has been mined from this area. The phosphate ores, locally termed matrix. are beds of sands and clays containing the phosphate pebbles, considered to be Pliocene in age, derived by marine action from underlying Miocene phosphatic marls, and are covered by practically barren sands and clays that have been deposited more recently. Open-pit mining is practiced; hydraulic mining, which has been intensively developed in this district, is used exclusively for mining the matrix and, by some companies for removing the overburden, although drag-line excavators have become established and are proving economical for stripping operations. From the pits the matrix is pumped to adjacent washing plants for beneficiation. The product of the washers. after drying, enters the world markets as Florida pebble phosphate.In this district recovery of the phosphate pebbles by the washing plants has not been particularly effective in the past. The screening, designed to effect a seperation at about 20 mesh (0.033 inches), has not been well controlled. Washer rejects discarded to the waste dumps have contained appreciable amounts of material analyzing above the minimum commercial grade - 66 per cent B.P.L. (bone phosphate of lime). Such losses of commercial fractions should be considered avoidable, and have been discussed at length in a previous paper.3"

Jul 1, 1930

By R. Karl Zipf, David Newman

The objective of this is paper is to review the current state of knowledge and practice in highwall mining (HWM). HWM has become a widely-applied method in surface mining, commonly used alone or in conjunction with contour or slot mining. It provides 800-feet to 1,200-feet of additional recovery when the economic stripping ratio is reached in contour mining or in slot mining when surface access to a reserve is limited. A significant attribute of the highwall miner is its versatility. HWM has been used successfully to mine abandoned pre-reclamation law highwalls, points or ridges uneconomic to mine by underground or other surface methods, outcrop barriers left adjacent to underground mines, separate benches of the same seam where the parting thickness or quality differences between benches render complete extraction uneconomic, previously augered areas containing otherwise inaccessible additional reserves and close or widely spaced multiple seams. The theory and design methods to assess roof, pillar, and floor stability are presented followed by three case histories. Simple design charts for sizing HWM web and barrier pillars are also presented. A recommended web pillar width may be obtained from the design charts given the overburden depth, the HWM cut width, and the mining height. Given the depth and panel width for a set of HWM cuts, another set of charts gives a suggested barrier pillar width. The case histories, from Northern and Southern Appalachia are used to illustrate the application of rock mechanics to quantify the stability of the highwall, roof, web pillars, and floor. The case histories involve 1) mining through a previously augered highwall, 2) mining under back-stacked spoil and 3) selective mining of closely spaced benches of the same seam. Because each site is unique, the appropriate pre-mining geotechnical analyses range from the calculation of roof, web pillar, and floor bearing capacity stability factors to detailed numerical modeling of the auger and underground mine workings. When operating in the vicinity of existing underground mine or auger workings, the determination of ground deformation and strains resulting from highwall mining is a necessary facet of a ground control investigation.

By Robert E. Johnson

1962 was the second year of recovery from the mild 1960-61 recession. The year-to-year gain in constant dollar gross national product, our most comprehensive measure of the country's economic performance, was 6.0 percent (from $447.7 billion in 1961 to $474.8 billion in 1962). The unemployment rate declined from 6.7 percent to 5.6 percent. Although it was a good year, there were still unused resources of labor and capital which implied that the economy was operating below its potential. The year-to-year change in the Federal Reserve Board (FRB) index of industrial production of 7.6 percent masked the fact that more than one-third of the growth took place within 196L The monthly index rose only 4.8 percent during 1962, from 114.3 in January to 117.8 in September. The fact that the economy as shown by the industrial index, rose rapidly in the first half of the year only to remain on a plateau of 119-120 during the second half, led some people to fear an imminent downward turn. This did not occur. Neither production nor consumption of mineral fuels advanced as fast as the total economy. But consumption showed more gain than production, 5 percent compared with somewhat less than 4 percent. Production of both crude oil and natural gas reached new highs while bituminous coal production was the highest in 5 years.

Jan 1, 1963

By L. J. Kane

Conventional methods for determining the size of dust suspended in a gas require that agglomerates (clusters of particles) first be broken into particles, but in evaluating industrial dust-removing equipment the size of the agglomerates as they actually exist in the gas stream is far more important. This paper presents results of an investigation by the Federal Bureau of Mines to develop methods for determining the size of dust agglomerates suspended in a gas stream. The studies are part of the Bureau's continuing research on synthetic liquid fuels. The size and size-distribution of agglomerates as they exist when the gas reaches the filter was determined by using a membrane filter in conjunction with a dust count under a microscope. A membrane filter is a cellulosic sheet about 150 microns thick containing millions of holes per square centimeter--holes of uniform diameter that run directly through the sheet without interconnection.

Jan 1, 1960

By Rudolf E. Greuer

The existing computer programs for the simulation of ventilation systems under normal ventilation conditions are reviewed and a suitable program for including the influence of mine fires is selected. New program parts are written for the consideration of methane productions in coal mines, heat and gas productions of mine fires, temperature and air composition changes in ventilation systems, and the ventilation forces resulting from the latter. Other program parts are provided for the detection of danger zones and reversed air currents and for the inclusion of recirculated air currents in the network analysis. Existing program and new program parts are combined. The resulting new program can be used for a multitude of assignments. It is designed for the practical ventilation engineer and should be applicable to all types of ventilation emergency plans, in particular mine fire plans. The organization of the program and its mathematical basis are described. A FORTRAN IV listing and several flow diagrams are included. Eight executed examples are discussed, input and output for these examples explained. Storage requirements and execution times are estimated.

Jan 1, 2011

By Frank B. Fulkerson

Barge traffic on the Nation's inland waterways over the past 15 years has been increasing at a rate much faster than intercity freight traffic by all modes, largely due to the growing consumption of mineral commodities, development of more powerful towboats and large and more specialized barges, improvements to loading and unloading facilities, and competition among bargelines for contract shipment of bulk commodities. The Bureau of Mines, in a study to determine barge traffic projections for inland waterways in the South-Central States to the year 1980, gathered data on origin-destination patterns by commodity, quantity moved, equipment used, and rates charged; the trend of each of these factors over time; and the extent of competition between water trans-port and other means of transportation. The Mississippi River and the Gulf Intracoastal Waterway, which together carryover half the Nation's barge traffic, are major carriers of coal, crude petroleum, steel, marine shells, sulfur, salt, cement, and alumina. Greater quantities of these products will be transported by barge; however, oil pipe-lines and unit trains for coal are expected to limit increased barge traffic of these two commodities. Increasing quantities of fertilizer materials will be transported upstream. Although congestion at certain locks is a current problem, the Mississippi River below St. Louis and other open-river stretches have the capacity to handle the increasing number of barges for the foreseeable future.

Jan 1, 1969

By Sidney Katell

This report, covering the period January 1969 through December 1969, is a continuation of a series that began with the publication of Information Circular 7516 in October 1949. It is the 11th in a series of reports prepared in cooperation with the American Association of Cost Engineers. The abstracted articles are concerned with all phases of cost engineering in the field of chemical and petroleum plants and related subjects. They are from the following sources: 1. American Association of Cost. Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal Mining and Processing.

Jan 1, 1970

Background: Frictional ignitions continue to be a problem facing the U.S. underground coal mining industry. Many methane igni-tions are associated with the impact of mining machine cutter bits on quartzitic material (e.g., sandstone) during the coal-cutting process. Most ignitions result in small methane-air fireballs often only a few feet in size and limited to the cutter head location. However, under certain conditions, frictional ignitions can lead to larger methane explosions and/or fires with the potential for causing serious injury or death to the mining machine operator and other nearby miners. The requirements for a frictional ignition are a flammable volume of methane-air and an ignition source. This source is usually the hot streak caused by the frictional impact of the mining bit on hard rock, and the frequency of occurrence increases with increased bit wear. Another possible ignition source is the fric-tional impact of rock on rock during a roof fall.

Mar 1, 2008

By E. R. Maize

This report is t e second of s series on roof movement in coal mines. The first (R. I. 3355)4/ dealt with convergence of roof and floor and movement of the surface accompanying and following extraction in a mechanized mine in which retreat of rib lines was rapid. The studies reported herein were made in a mine in which all the coal is loaded by hand, and movement of the rib lines was much slower in consequence. In choosing a site for this work, it was decided that the mine selected should have natural conditions akin to those of the first study and entirely different methods of working. To this end a cooperative agreement was made with the Crucible Fuel Co. through W. J. Whitaker, secretary, for conducting the work in the company?s Crucible mine, operating in the Pittsburgh bed in Greene County, Pa, This paper gives an account of the methods used in the investigation, excerpts from the data obtained, and such generalizations as can be made.

Jan 1, 1939

By Pablo Velasco

The Belize economy recorded modest growth during 1980; the growth of the gross domestic product (GDP) in real terms was between 1% and 2%. At current prices, the 1980 GDP reached $108 million2. This output was largely attributed to the performance of a few industries, mostly nonminerals. Such performance improved significantly the balance of payments situation by reducing the deficit from $19 million in 1979 to $4 million in 1980. The rate of inflation was an estimated 18% in 1980 and would have been greater if not for a conservative monetary policy and price control on a number of essential items. Expert earnings increased $43 million, or 50%, from the 1979 level. After increasing more than 25% in 1979, imports increased only 6% in 1980 to a level of $141 million owing to the decline in investment and stabilization of petroleum prices. The balance of trade deficit was $9.8 million in 1980, a marked improvement from the 1979 level of $45.1 million. The mineral output for Belize accounted for only a fraction of 1% of the GDP. Such activity was limited to the production of limestone, marl, and sand and gravel, all of which were primarily used in construction of the Northern Highway between Orangewalk and Belize City. Mineral resources are deficient or nonexistent in Belize for the majority of metals and nonmetals, although the Government and others continue to believe that petroleum must exist in Belize. The proximity to Mexican oilfields and the growing finds in the Peters area of Guatemala support this expectation. The Government continues encouraging exploration onshore and offshore and offers terms that

Jan 1, 1982

By Sidney Katell

This report covers the period January 1964 through December 1964; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the sixth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facers of cost engineering in the field of chemical and petroleum. plants and related subjects, are from the following sources: 1. American Association of Cost Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress,

Jan 1, 1965

By J. E. Allison

As part of a Bureau of Mines research program to conserve critical and strategic metals, an aqueous electrodeposition method for preparing stainless-steel-type coatings was studied. Chromium powder (averaging 3 J1.m diam) was suspended in a ferrous-nickelous sulfate electroplating bath and occluded in the electrodeposited Fe-Ni alloy matrix. Subsequent heat treatment of the resulting composite coating formed the ternary alloy. The occlusion process was affected by the quantity of Cr powder suspended in the electrolyte and by the microstructure and composition of the electrodeposited matrix. Coatings containing up to 21 wt pct Cr were deposited from an electrolyte containing 20 vol pct suspended Cr powder. Heat treatment at 1,100° C for 8 h homogenized the composite coating. Deposition of 44Fe36Ni20Cr alloy coatings (250 J1.m thick) on AISI 1020 carbon steel rods, followed by heat treatment, provided complete protection of the carbon steel during exposure to a boiling 65-pct-HN03 solution. Corrosion rates of 0.6±OA mm/yr for the coating in the boiling HN03 approximate that of 304 stainless steel. Practically shaped electroforms have been prepared by the coating method.

Jan 1, 1989

By Sidney Katell

This report covers the period January 1964 through December 1964; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the sixth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facers of cost engineering in the field of chemical and petroleum. plants and related subjects, are from the following sources:

Jan 1, 1965

By Thomas Varley

During the past few years, since flotation has become the paramount treatment method for most all kinds of ores, the Bureau has gathered the data on consumption of reagents used in the flotation treatment. The first report was issued in 1916. A brief review of such reports snows the progress made in the art of flotation, and each year brings forth the development of new reagent a or combinations of reagents that seem sure to survive, but research and progress spell their defeat, if not by entire elimination, at least subjects them to considerable modification.

Jan 1, 1928

By Reynold Q. Shotts

A study was made of the coal resources of an area in Jackson County, Ala., forming a part of the Flat Rock, Henegar, and Stevenson quadrangles. The area studied is a portion of the Plateau coalfield on Sand Mountain and is near the Tennessee Valley Authority's Widows Creek steamplant. Since no detailed geological study of this area had been published, some reconnaissance work was done. The coalbeds and adjacent strata such as sandstones, conglomeratic sandstones, and conglomerates were studied. Available drill logs, together with the areal geology, provided sufficient information to permit correlation of the coalbeds and an estimation of coal reserves. For all categories of reserves, computed on a regional basis, a total of 72,920,000 tons of coal more than 14 inches thick is estimated for the areas studied in Stevenson, Flat Rock, and Henegar quadrangles. Of this tonnage, 40,001,000 tons is estimated to have less than 60 feet of overburden. The total measured coal reserves for the above three quadrangles are 16,359,000 tons, with 12,411,000 tons under less than 60 feet of cover.

Jan 1, 1966

Mineral production was of little significance in the country's economy, and Bangladesh was not a world-ranked producer of any mineral commodity during 1977. Natural gas was the most important mineral exploited; however, reserves were sufficient to allow for much greater production, Economically, Bangladesh made some progress in 1977-782 in its struggle against poverty, underdevelopment, and rapidly increasing population. The gross domestic product (GDP) grew 8%, mainly owing to a 13% increase in food grain production, the key economic indicator in this highly agricultural nation. GDP at current prices dropped slightly in Fiscal Year (FY) 1976.77 to $6.6 billion3 and rose to $7.2 billion in FY 1977.78. The population rose from 81 million in FY 1975-76 to about 85 million in FY 1977-78, resulting in an increase of per capita GDP from $83 to $85 during the same period. The high annual population growth rate, over 3% in 1976 and about 2.8% in 1977, was recognized by the Government as the main problem facing the country. Average density was 525 people per square kilometer. A similar density would have the entire world population living within the continental United States.

Jan 1, 1981