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Compare the fire endurance of paneled steel stoppings with that of traditional concrete block Stoppings. Background Permanent stoppings or partitions arc used in mines to separate ventilation airways. The ability of stoppings to retain their structural integrity for a minimum length of time under lire conditions and prevent the spread of flame and toxic combustion products to an adjacent airway is critical. The success of miners in reaching safety during a fire depends largely on the presence of uncontaminated airways. Traditionally, permanent stoppings for coal mines are constructed of concrete blocks. Recently, paneled steel stoppings that satisfy many of the requirements demanded of permanent stoppings, such as incombustibility and strength, have been introduced. Their use also introduced concerns such as the ability of a steel stopping to maintain its ventilation control function when exposed to a fire and the potential that the fire could transmit enough heat through the stopping to ignite combustible materials on the unexposed side. To address these concerns, the Bureau of Mines investigated the fire endurance of galvanized steel and concrete block stoppings.

Jan 1, 1989

During 1990-1999, a total of 458 fires occurred in all coal mining categories; 157 of those fires caused 164 injuries and 2 fatalities. The greatest number of fues and fire injuries occurred at surface mines, whch also had the highest risk rate values. A total of 66 fuefighting interventions were required. Of these, there were 25 mine rescue team interventions in underground mines, including 5 mobile equipment firefighting interventions, and 41 fire brigade and fire department interventions at all surface operations, including 19 mobile equipment interventions. In all, 50 fires destroyed or heavily damaged equipment (including 16 pieces of mobile equipment) because of failure of other firefighting methods, late fire detection, undetected fires, or fire size. A total of 1 14 fires were detected late by smoke, and 42 fires were not detected.

By Jerry Olson

The Bureau of Mines (Bureau) conducted a mineral resource investigation of the French Creek-Patrick Butte study area, in west central Idaho during 1989. No mineral resources or significant occurrences were identified. Other than small scale placer gold, no mineral production is known or recorded. At least 100 lode and 150 placer claims have been located in the study area. Most of the area was examined by ground or areal surveys, and 110 lode and 60 placer samples were taken. Four lode prospects were examined in detail, and all placer claim locations were sampled.

Jan 1, 1991

By S. Gallagher, A. Mayton, R. Merkel

The prolonged exposure of equipment operators to shock and whole-body vibration (WBV) is linked to cumulative back, neck and abdominal disorders. In low coal mines, space restrictions make it difficult for seat suspensions to isolate operators from shock and WBV Researchers at NIOSH's Pittsburgh Research Laboratory are responding to these issues by investigating viscoelastie foams. For the full-load case, an ergonomic seat made with viscoelastie foams can isolate the shuttle-car operator from shock at 15 Hz. Researchers used results from additional foam testing using an analytical model to identify viscoelastic foams that provide shock isolation at a frequency below 5 Hz.

By I. Iwasaki

In recent years the rapid depletion of high-grade iron ores and the demand by blast furnace operators for increasingly low-silica ores have stimulated interest in flotation studies of low-grade iron ores, such as wash-ore tailings and oxidized taconites. Four processes have been reported for the flotation separation of these iron ores--anionic and cationic collection of the iron oxides, cationic collection of siliceous gangue, and anionic collection of activated siliceous gangue (5).5/ The effectiveness of any one method, however, depends largely on the mineralogical composition and on the physical structure of the sample; hence, a comprehensive study of the floatability of the individual minerals occurring in these materials is essential. A review of the literature shows that the floatability of hematite and magnetite has been frequently investigated, whereas very little corresponding information is available for goethite, or for its more earthy form, limonite, both of which are abundant in the Mesabi and Cuyuna ores (19). The purpose of this investigation was to formulate general information on the floatability of goethite. Vacuum flotation, contact angle measurement, and simplified flotation tests using a modified Hallimond tube were used. The experimental results were correlated with the electrokinetic properties of goethite as determined by streaming potential measurement. The results were used to interpret the batch flotation tests made on an artificial mixture of quartz and goethite.

Jan 1, 1960

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

C.5 Safety Equipment and Control Devices Safety equipment and control devices serve two principal functions in mine escape hoists. First, they can be used to provide important safety features such as protection against overspeed, over¬travel and undertravel. Second they can be used to automate or partially automate the operation of the escape hoist. Typical equipment available is described in the following section. 1. Simplex and Lilly Hoist Controllers Manufacturers: Logan Actuator Co. 4956 No. Elston Ave. Chicago, Illinois 60630 312-736-7500 The Simplex and Lilly Controllers provide a means for electrically shutting off the power to the hoist and the energy to physically set the brakes in the event of overspeed, overtravel, undertravel and failure to begin deceleration within sufficient distance

Jan 1, 1976

By George A. Morgan

The production and processing of crude petroleum and natural gas are the dominant economic sectors of the Middle East. Development of downstream petrochemical and fertilizer industries continues as a major investment area. In 1993, the 15 countries that constituted the region accounted for 29 % of world crude petroleum output, 19 % of world natural gas plant liquid production, and 6 % of world dry natural gas production. Only Cyprus and Lebanon were not crude petroleum producers. Regional output was up for most major mineral commodities. A major exception was phosphate rock, which declined sharply owing to reduced worldwide demand. Total crude petroleum output declined by over 100 Mbbls, again owing to slack demand in the major industrial countries.

Jan 1, 1995

By W. J. Johnson

This report presents the Phase I progress in the development of a Radar Coal Thickness Sensor (RCTS) being conducted by Boeing Aerospace and Electronics for the Bureau of Mines. A method is developed for measuring both the dielectric constant and depth of the coal shale interface using a modified UHF network analyzer and antennas in proximity to the surface of the coal. Both bistatic and monostatic systems, are compared. The algorithm technique uses synthetic range gating for clutter rejection and full polarimetric scattering matrix techniques to extract the dielectric constant and depth to sub-wavelength accuracies. Tests were run both in the lab and in a coal mine to build an error budget and demonstrate a validation of the model. The development of a prototype radar suitable for coal mine robotics is specified.

Jan 1, 1990

By Richard J. Leary

The inputs of capital and labor to support future iron ore production were developed by the Bureau of Mines from projections of iron demand and estimates of capital and labor requirements. Trends in technologic change and the organization of production were analyzed. Labor requirement schedules for iron ore mining and beneficiating were constructed from aggregate inter-temporal trends and 1970 cross-sectional analysis of mines and mills. A sup-ply schedule of the capital requirement for mine-mill-pellet plants was developed from U.S. and Canadian experience. The structure of demand for iron to the year 2000 was examined as well as the availability of resources. Projections of capital and labor requirements to 2000 were constructed under two international patterns of iron ore supply to the United States. The most likely model is for a continuation of the 70 percent United States-30 percent foreign shares, expanding at an average 2.0 percent growth rate to 2000, and supported by a cumulative gross capital investment of $3.8 billion constant 1967 dollars and a labor force in the United States of 29,800 by 2000. The information content of projections is discussed, and the possible effects of international forces on supply are considered. A generalized methodology for estimating capital and labor requirements in other mineral industries also is included.

Jan 1, 1975

By Stephen Utter

This report summarizes the procedure and results of an investigation to determine the stresses in the rock around an underground opening in the Climax molybdenum mine, Climax, Colo. This study is part of an overall investigation conducted by the Bureau of Mines to determine the stresses induced by block-caving mining. The purpose of this study is to obtain estimates of the magnitudes and directions of the principal stresses, the location of the maximum stress concentrations, and the effect of topography on the stresses.

Jan 1, 1962

By NIOSH Publications

In 2004, 14,478 mining operations reported employment statistics to the Mine Safety and Health Administration (MSHA). Almost half (48.9%) were sand and gravel mines, followed by stone mines (30.4%), coal mines (13.9%), nonmetal mines (5.1%), and metal mines (1.7%).

Sep 1, 2007

Provide a method for obtaining in situ measurements of coal cutting forces which are needed for mining machine design. Approach A portable in-seam testing device is carried to the face of an underground coal mine heading to measure the cut-ting force encountered by a continuous miner pick directly at its maximum depth of cut. How It Works The tester frame is attached directly to the coal surface with four one inch diameter threaded studs resin-bolted into 1-1/4 inch diameter holes which are drilled 30 inches deep. Spherical nuts and washers compensate for misalignment between the bolts bearing plate, and traverse beams. Spacers can be placed over the studs to assure that the traverse beams remain in the same plane. Cutting forces are applied by a hydraulic cylinder that moves the pick of the tester through a twin-chain arrangement which gives a 20-inch cutting stroke with

Jan 1, 1982

By John Gross

In connection with some investigations being made at '!'he Ra.re uid Precious 1ets.ls Station of the U, S. Bu.rea.u of Mines, at Reno, Nev., on the precipitation of gol'i and silver from cyanide solutions, it wa.s sug­ gested tnat the use of acetylene for this purpose be investigated, A pa.tent was iss·.ied to Fre<!.erick W. Martin and Frederick Stl1.bbs in 1900 covering the precipitation of precious metals from cyanide solu­tions by acetylene, The acetylene used in the tests described below wa3 made f'rom a. corr.:nercial cal ci \'!Z:l carbid.e, A r..umber of exper:me11. +,s rezul ted in more or lP.ss ccmplete pree;p1tatien of silver, -but 1n no case was a11Y gold precipitated. As silver acetylide, obtained by precipitatir.g the silver from an ar:::ncni'i\.Ca.l so1ut1on of silver n,. tra.te by acetylene, is yellowish white, esn:, solu'.)le in cyanide and hlghly explosive, and the pr9cip1tate ob­tain£ frcvm the cy'31lide sclutions was black, not tlubla L., cyanide and not explooive, it 'Na.s deid-,d. to ir.·.restigate the na.tur.e of the slJ.ver pre­cipit.te !rem the cy;r:iide solu·t:i.i,ns, !n prepa;.•i::lg a lge (!\,wrttity ,:f the preci-pi tte 1 t. wa, fo·und that a.fter c,:.\i;:1 ete prEc"'.pi tat ion cf the eil ver the !IOl ution con ta.ined soluble eulphic.e • Thia p:!:'O'lided a el f!W "lt·d. a.ft er apr,ropri-9.te tests the preeipita.te VIO,I proved to 'be ailver sulphide.

Apr 1, 1922

By E. P. Youngman

The mining law now in force in Finland is the Imperial Russian Ukase of 1883, promulgated November 12, 1883, by Czar Alexander III, with the sanc- tion and permission of the Finnish Estates. This law repealed prior legisla- tion, as follows: Crdinance of liay 25, 1857, concerning the appropriation of ores and minerals; as wall as the right to remove and utilize them; proclama- tion of January 20, 1868, amending, the ordinance of May 25, 1857; proclama- tion of October 3, 1621, concerning the appropriation of precious metals; and the proclamation of October 30, 1878, concerning prospecting for gold, etc., in Finnish Lapland. A proposal for a new mining lar is still being considered by the Finnish Diet. This new law, if and when promulgated, will differ only slightly from the law of 1683 but will be drafted in more modern language."

Jun 1, 1932

Provide a full-scale test facility where the effectiveness of all types of subsidence abatement techniques can be evaluated under controlled conditions. Background Subsidence is ground movement resulting from the collapse of overlying strata into a mine void because of failure of the mine roof, mine floor, or support pillars. The failure may propagate to the surface and be expressed as a depression, cracks, or a sinkhole. The surface expression of such features may be delayed until long after mining has been completed. Subsidence has the potential to affect more land area than any other type of abandoned mine land problem. Subsidence also causes direct damage to real property, with significant financial loss and more importantly, presents a danger to public health, safety, and general welfare. Subsidence-related problems are considered to be one of the most important abandoned mine land issues. Backfilling of mine voids is the most common stabilization method used to abate subsidence and protect surface structures. Backfilling or placement of material is performed by hydraulic flushing or pneumatic stowing, using either in-mine or remote methods. The majority of the past subsidence abatement projects has been performed using remote methods from single or multiple boreholes. Other subsidence abatement techniques arc available. For example, various point support methods are used to protect small areas of the land surface and surface structures, without completely filling the mine void. These may be more appropriate under different conditions. Little documented information is available concerning the capability of the various backfilling methods for completely filling a mine void or providing long-term structural strength. Therefore, the Bureau of Mines developed a laboratory for controlled evaluation of backfilling technologies.

Jan 1, 1991

By A. D. Garman

This paper presents one of a series of digests of foreign mining leg- islation and court decisions which is being repared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countrics. This interpretation of the laws of Panama has been prepared from the best available information in Washington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers to who it is being referr ed through the courtesy of the Department of State.

Apr 1, 1930

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&apos;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 Lloyd A. Morley

Proposed advantages and disadvantages of low-voltage shielded trailing cables are formulated utilizing the literature and industry sources. A partial analysis of these proposed advantages and disadvantages is completed through a review of the literature. Cable costs are assembled from mine operators, cable and splice manufacturers, and actual cable purchases. To confirm each advantage and disadvantage, an underground test site is established, and testing is performed here and in the laboratory. All testing procedures are completely described. The results of this investigation are reported and used to formulate recommendations attendant to low-voltage shielded cables. Suggestions for installation, handling, and maintenance are presented.

Jan 1, 1977

By T. H. Jeffers

Significant amounts of cobalt are present in readily accessible spent copper leach solutions. The Bureau of Mines investigated the feasibility of extracting cobalt from these solutions in a multiple-compartment ion-exchange (MCIX) column. The effects of aqueous flow rate, resin flow rate, column height, and compartment height on cobalt extraction were determined. Cobalt extractions of 92 pct or higher were achieved at solution flow rates of up to 5.5 gpm/ft of column cross-sectional area and an aqueous-to-resin flow ratio of 40:1. Overall cobalt extraction increased as the column height increased, but cobalt extraction per unit of length was more efficient in 8-and 12-ftco1umns than in an 18-ft column. Solvent extraction procedures were utilized to purify and concentrate the MCIX column eluates and produce a cobalt sulfate solution containing 70 to 80 giL Co. Metallic cathodes containing over 99 pct Co were e1ectrowon from this solution. Zinc, nickel, and copper byproducts were also recovered during processing of the ion-exchange eluates. Estimated total capital cost for a commercial-scale 10,000 gpm of a spent leach solution containing 26 million. With credits for zinc, nickel, and copper estimated net operating cost was $9.36/lb Co.

Jan 1, 1987

By Charles Vaught

This paper discusses the fact that US coal mining organisations are losing the knowledge they need in order to be able to respond to emergencies. The authors note that knowledge management provides a useful perspective from which to view the problem, but that the debate about what constitutes knowledge should be broadened to include a debate about what constitutes management. It is argued here that knowledge is actually shared knowing distributed across group members; that such knowledge can be managed by cultivating it; and that narrative is the medium through which this may be done. The paper then examines NIOSH research that has attempted to use such an alternative knowledge management approach to help potential mine emergency responders better deal with the predicaments they are likely to encounter on-site.

Jan 1, 2006