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By S. H. Ash

In the early nineties it was observed by several European investigators and by C. S. Rice4 that an explosion could be checked and would not propagate in the parts of a mine where shale or other inert dust was present in large amounts.5 After the disastrous Courrieres explosion in France that killed 1,100 men, coal-dust explosion tests were made in France in 1907 and in Great Britain in 1908 which resulted in the conclusion that if enough incombustible dust were properly spread throughout passageways charged with coal-dust, the propagation of an explosion by the coal-dust could be prevented. In 1908 the Federal government authorized the investigation of the causes of mine explosions and of possible methods of preventing them, with the result that during 1911 the United States Bureau of Mines, after making several tests, suggested that rock-dust be used in gassy or dusty bituminous coal mines. Since that time, experiments and investigations6 have proved conclusively that widespread explosions can be prevented in coal mines by efficient rook-dusting.

Jan 1, 1930

By Kenneth H. Johnston

This report describes an in situ combustion project and three waterflood projects in Allen, Anderson, and Wilson Counties, Kansas, that will be visited during the 1964 annual tour of the Kansas-Oklahoma Waterflood Association. Among the unique features of the projects are the movement of heavy crude oil through the reservoir and into the wellbore with energy furnished by burning a portion of the crude oil therein. Another feature is the simultaneous injection of C02 and water, through separate tubing into input wells during early development, to increase injectivity at moderate pressures, Discussion of individual projects includes information on their early history, source and treatment of injection fluids, oil production-decline curves, and the results of water injection on oil production.

Jan 1, 1964

By Robert E. Manning

The Federal Coal Mine Health and Safety Act of 1969 has placed stringent limitations on the noise levels in which employees may work. This act can result in both increased labor costs because of noise-exposure time limitations and in high capital costs for modification of present equipment, and the design of new equipment, to comply with the law. The development of new noise-control systems is thus of immediate interest to industry. A current Research program at U. S. Steel is aimed at developing methods of controlling both the exhaust-air noise and the mechanical noise of a Stoper drill, a pneumatic percussive tool used for roof-bolting purposes in coal mines which has an approximate air consumption of 100 cubic feet per minute. This program is being performed under a contract between USS Engineers and Consultants, Inc. and the Pittsburgh Mining and Safety Research Center of the U. S. Bureau of Mines. In previous work at U. S. Steel, kidney-shaped mufflers were designed that wrap around the air leg of the drill for control of the exhaust noise. These mufflers were designed with the aid of a digital computer program that predicts the acoustic performance of mufflers.

Jan 1, 1975

By John C. Cook

This was a study to identify and evaluate known technologies employing electromagnetic resonance phenomena in solid minerals for their identification and assaying, particularly assay logging of exploratory boreholes. A comprehensive literature search and study revealed some little known NMR (nuclear magnetic resonance) techniques developed by Professor G. J. Béné's group at the University of Geneva, Switzerland. These are suitable for use in weak, inhomogeneous magnetic fields. Laboratory NMR tests of numerous U.S. ore minerals showed good identifying signals from phosphates, fluorspar, bauxite, oil shale, and spodumene (lithium) ores, but not from the copper, lead, antimony or manganese ores tested. Use of EPR "signatures" for such ores is suggested. A conceptual design for an NMR assay logging system is proposed.

Jan 1, 1978

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations 4251. The tactual data obtained during the project are reported in a series of Reports of Investigations beginning with No. 4251, of which this is the twelfth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate halt-township map. The description of each half township is followed by a description of each deposit developed in that halt township. The 14 half-township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project except the deep holes drilled to test the geophysical anomalies. The locations of those holes show on figure 13 in volume 1. The descriptions of the deposits developed are followed by complete detailed logs of the drill holes. Many of the widely spaced exploratory holes did not discover bauxite of minable thickness and grade. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated, and a table for each half township is given with the discussion covering that area.

Jan 1, 1948

By G. S. Scott, G. W. Jones

Trichloroethylene (CHC1CC12) is an important solvent for fats , resins , bitumens, rubber , sulfur , and phosphorus . It is used extensively in drycleaning because of its low order of combustibility and has recently been proposed as an inhalation anaesthetic . Its physical properties have been described by Carlisle and Levine . It is usually considered a noninflammable material ; however , substances that are noninflammable when mixed with air are not necessarily noninflammable when mixed with oxygen . Thus , Hewer's statement that " Trichloroethylene*** is not inflammable under any circumstances , nor will its vapor explode when mixed in any proportion with air , oxygen, or nitrous oxide , " requires qualification , especially in anesthesia, where pure oxygen may at times be substituted for air , This report gives the results of tests made to determine the inflammability of trichloroethylene in various mixtures of oxygen and nitrogen . The trichloroethylene used was Eastman's No. 1300. The boiling point was given as 86 ° to 87 °C . The specific gravity and refractive index of the sample measured in this laboratory were , respectively, 1.45 and 1.4759 at 25 °C .

Nov 1, 1942

By Phillip R. Moyle

A basic precept in mineral exploration is that the best places to prospect are where minerals have already been found. The California desert has many old mining districts once thought to be "played out" that are currently producing more mineral wealth than at any time in the past. Because no "crystal ball" exists that will enable us to predict the Nation's future mineral needs, land management plans must be flexible enough to respond to these often unforeseen needs. MANAGEMENT ISSUES The California Desert Conservation Area (CDCA) (figure 1) encompasses 25 minion acres, nearly one-quarter of the total area of California. Passage of the Federal Land Policy and Management Act of 1976 (FLPMA) launched an intensive program by the Bureau of Land Management (BLM) to study this vast area. Painstaking scientific investigations were made of wildlife and plant populations, soil, air, and mineral resources, range use, and wilderness characteristics, among other environmental concerns.

Jan 1, 1992

By G. W. Birge, D. E. Wolfson, J. H. Lynch

This report presents all available 900 ° C BM- AGA carbonization and related data for coals from the principal beds of the southwest Virginia field in a form which permits ready comparison of product yields and properties of coals and cokes . Thirty- one channel samples from Buchanan , Dickenson , Russell , Tazewell , and Wise Counties were carbonized at 900 ° C in an 18 - inch - diameter retort . Blending properties of 10 of the coals were studied , and expansion of most of the coals and blends was measured in the Bureau of Mines sole - heated oven . Ash Most of the samples were chemically suitable for metallurgical use in coking blends , and their coking properties generally were satisfactory . content exceeded 10 percent in only three samples , and none of the coals contained more than 1.5 percent sulfur . Dry , mineral - matter - free fixed - carbon content of the coals ranged from 62.1 to 77.5 percent . Expansion behavior varied widely , ranging from 16.8 percent expansion to 27.6 percent contraction .

Jan 1, 1964

By M. M. Fine

The flotation work on samples from nine fluorspar properties in Crittenden and Livingston Counties, Ky., reported herewith was part of a wartime project that resulted in increasing the supply of metallurgical-grade fluorspar. The samples were tailings, dumps, and waste rock that had been rejected in previous milling operations. All were treated successfully by flotation to yield metallurgical-grade concentrates with recoveries ranging from 77.5 to 98.3 percent of the fluorite. After the laboratory testing, the results of which were available to the owners and operators of the properties, many of the tailing ponds and rock dumps were milled. The real value of this report, therefore, is to show the operators of gravity concentration plants the possibilities of re-treating waste products by flotation either at some future time or currently with the gravity

Jan 1, 1948

Table 1.-Salient statistics of carbon black produced from natural gas and liquid hydrocarbons in the United States [ ]

Jan 1, 1967

By Jerry E. Olson

In 1988, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied additional areas, encompassing 11,303 acres, on the east and west sides of the 20,727-acre Badlands study area (Olson, 1987) in order to evaluate their identified mineral resources. The Badlands study area additions are located in Crook and Deschutes Counties, OR, about 10 and 18 miles east of Bend, OR. No mineral resources were identified. The additional areas studied are underlain by Tertiary-and Quaternary-age basalt flows which are largely covered by a veneer of sand and silt. No mines, prospects, mining claims or mineralized areas occur within or near the Badlands study area additions. Slab lava of marketable grade and quantity was not found in either area. None of the study area is of current interest for geothermal resources, but the eastern study area addition has been leased (1984) for oil and gas.

Jan 1, 1989

By B. J. Scheiner

As part of the goal to maximize minerals and metals recovery from primary domestic resources, design factors associated with minimizing current leakage in bipolar cell configurations were studied by the Bureau of Mines as a means of improving the efficiency of bipolar e1ectrooxidation cells. Initial studies that were conducted in a small bipolar cell operating at 140 to 145 volts and 15.4 amp indicated how design factors could be employed to minimize cur-rent leakage around adjacent electrodes during cell operation. Based on these results, a 40-electrode, 108-kva prototype of an industrial-sized cell was constructed and tested for extracting metal values from offgrade molybdenite concentrates. The feasibility of recovering molybdenum and rhenium from the oxidized pulp also was determined. Feed to the process sequence consisted of flotation concentrates containing 16 to 35 pet Mo as molybdenite and 6 to 15 pct Cu. E1ectrooxidation in the prototype cell resulted in 84 to 97 pct Mo and Re extraction with a corresponding energy consumption of 9 to 13 kwhr/1b Mo extracted.

Jan 1, 1979

By Scott W. Hazen

This report describes the design, analysis, and results of a special experimental mine-sampling project conducted as part of the Bureau of Mines continuing program on sample-methods research. The experimental project was conducted at the Bureau?s Denver Mining Research Center and at the Climax molybdenum mine within the framework of a cooperative research agreement between the Bureau and Climax Molybdenum Co., Division of American Metals-Climax, Inc. The primary objective of the project was to investigate the interrelation-ship between sample volume, number of samples, the standard deviation of an assay distribution, and the precision required for an estimate of grade of ore, and to develop this interrelationship into a relatively simple method of application for use in mine sampling.

Jan 1, 1962

By D. E. Wolfson

This report describes the carbonizing properties of the principal coal beds of Allegheny County, Pa., which rank low in the high-volatile A bituminous classification. Seven coal samples from 3 coal beds were selected for study, as follows: 2 each from the Redstone and Pittsburgh beds and 3 from the Upper Freeport bed. Selection was based on estimated reserves. The samples of Upper Freeport and Pittsburgh coals were satisfactory chemically for producing metallurgical coke. The ash contents of the samples of Redstone coal were moderately high. One of the samples of Redstone coal was high in sulfur content, and it would be difficult to upgrade to meet present metallurgical standards.

Jan 1, 1959

By A. B. Hooker

Nineteen of the installations were on rental contracts 1.L."'1der whtch the lamps belong to the lamp company and are rented by t.½em to the mine operatj.nt; company. · The other nine installations had been upon an O\Vnership-rental basis, by which the lamps had become the property of the renter at the end of 5 years. Five of t.11e rentec installations were en a special contract calling for a guaranteed light output. These contr2.cts were based upon certified . initial performance, with the provision that the lamps be replaced whenever periodic tests of fully charged lamps, taken at random from t..h.e charge racks, showed a light output of less than 80 percent of the certified performance.

Jan 1, 1942

PURPOSE: Evaluate practical technological advances in hearing protective devices for use in different mining environments RESEARCH SUMMARY: Previous NIOSH research shows that miners develop hearing loss much more quickly than nonoccupationally noise-exposed individuals and that miners experience a greater severity of hearing loss than would be expected for nonoccupational noise-exposed persons of the same age and sex. As described in the National Occupation-al Research Agenda, problems created by occupational hearing loss include(1) reduced quality of life due to social isolation and unrelenting tinnitus,(2) impaired communication with family members, the public, and coworkers, (3) diminished ability to monitor the work environment (i.e., warning signals, equipment sounds, etc.), (4) lost productivity and increased accidents resulting from impaired communication and isolation, and (5) expenses for workers? compensation and hearing aids.

Jan 1, 2001

By Richard H. Spencer, Thomas E. Doerfler, Robert L. Lagace, James M. Dobbie, William S. Hawes

This report assesses the expected detectability, on the surface above mines, of electromagnetic signals produced in the frequency band of 630 to 3030 Hz by a rescue transmitter activated by miners trapped underground. This assessment is based on a statistical analysis of experimental signal and noise data taken at a representative sample of coal mine sites well distributed over the United States underground coal fields. Regression analyses are performed to characterize the signal transmission behavior of overburdens as a function of depth and frequency. The predicted signal behavior is then combined with experimentally based distributions of the background noise, and aural detection characteristics of signals in noise, to generate curves of the expected probability of detection for trapped miner signals versus overburden depth and operating frequency. The implications of these results, and associated recommendations, are presented regarding the detectability of trapped miners, sensitivity analyses and confirmatory tests, and operational utilization considerations for the trapped miners and the search and rescue team on the surface.

Jan 7, 1980

By F. S. Crawford

This report deals with the effectiveness and economy of installing mine timbers treated with preservatives in long-life service locations. Early in the present century, when mine timbers and labor were plentiful, it was not general practice to install treated timbers in such places. Because national sources of good mine timber are declining steadily, the mining industry must now conserve timber. Moreover, the cost of installing and replacing mine timbers has been rising. Therefore, even the simplest of treatments can be expected to give some return on the investment when applied to timbers that are to be installed in relatively permanent locations. Better methods of treatment will produce better returns. In a service test of maple timbers treated by the hot-and cold-bath method and installed in main haulageways of the Athens mine of the Cleveland Cliffs Iron Co., Negaunee, Mich., zinc chloride-treated timbers had an average useful life of 13.3 years; borax-treated timbers, 11.2 years; and sodium fluoride-treated timbers, 7.7 years. Untreated timbers used as controls had an average useful life of 3.8 years.

Jan 1, 1950

By Thomas G. Murdock

ALTHOUGH the contribution of Algeria, including the Sahara, to the local economy and to world mineral supply was small for many years, the spectacular development of an important petroleum and natural-gas industry has changed the position of the country. In 1963 there were decreases in output of most mineral commodities, however oil and gas production forged ahead and established new records. The impact of adverse market conditions and especially the competition from lower cost producing areas was felt by both the metals and nonmetals industries. This and the general economic conditions related to the recovery of the country following the years of strife attending its emergence as an independent state combined to hold back production and development commensurate with resources. The principal events of the year were in the petroleum sector and included the first commercial production from several new fields, some new discoveries, the virtual completion of the first petroleum refinery in the country, and installation of additional pipelines. Progress was made toward the further utilization of the vast resources of natural gas and the provision of additional transportation and refining facilities. In the mining domain the government took over two iron-mining operations, and progress was made towards expanding production of phosphate rock and determining methods of upgrading the Tindouf Iron ores. Completion of the iron and steel plant near Bone was further delayed. The only coal mine reportedly closed down in late 1963.

Jan 1, 1964

By J. M. Seward, W. D. Dietzman, M. E. Hawkins

Analytical studies of formation waters are widely used by the petroleum industry as an aid in solving problems such as identifying intrusive waters , corrosion studies , treating injection water , and choosing open or closed water- injection systems . The solution of a problem is often simplified when reliable analyses of the waters under consideration have been made previously . Chemical analyses and electrical resistivity measurements are presented on 267 samples from 74 fields in south Arkansas , and 199 samples from 80 fields in north Louisiana .

Jul 1, 1960