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By E. Morrice

High-purity lanthanum metal was prepared by electrolysis of La003 in a LaF3-LiF-BaF2 bath at 950° C. The requisite bath temperature for the deposition of molten metal was maintained by supplying the heat as current directly to the electrodes. A current efficiency of about 60 percent was obtained. The lanthanum nodules contained carbon and oxygen as major impurities. The total impurity content was from about 0.1 to 0.2 percent.

Jan 1, 1962

By Charles L. Kusik

As part of an effort to establish processes that could be exploited in case of adverse changes in international chromium production and trading patterns, this study was sponsored by the Federal Emergency Management Agency (formerly the Federal Preparedness Agency) through the Bureau of Mines, to experimentally determine the feasibility of recovering chromium from critical scrap metals containing significant quantities of this element. Based on a conceptual pyrometallurgical chromium recovery flowsheet developed at Arthur D. Little, Inc., the experimental program described in this report demonstrated key process steps for the recovery of chromium as ferrochromium in a batch process. The process involves oxidation of chromium into a slag phase, subsequent separation of the slag phase from the remaining metal, followed by reduction of chromium from the slag phase to produce ferrochromium.

Jan 1, 1981

Provide blasting-resistant, quickly reusable stoppings for large mine openings. Approach Stoppings are assembled using roof-to-bottom panels of brattice held together by Velcro seams that peel open when struck by a strong air blast. How It Works The Velcro seam is designed to open when exposed to forces lower than would normally damage the brattice. When the seams partially open, they relieve the blast air overpressure to prevent damage to the brattice panels and their anchoring devices. A stopping is returned to service by reclosing the Velcro seams. To hang a brattice panel, its top is stapled to a board, and wrapped once or twice around it. That assembly is then attached to the roof with bolts. The length of the board should be a foot less than the width of the panel to allow for the sealing seam on each side of the panel. The boards are installed end-to-end in an approximately straight line across the roof of the mine opening.

Jan 1, 1979

By W. H. Young

THE BITUMINOUS coal and lignite industry declined slightly in 1961, compared with the 1960 figures. All of the major items, production, consumption, average value, exports, and employment, declined. Even the steady upward trend in mechanization failed to materialize; the percentages of total tonnages mechanically loaded and cleaned remained the same as in the preceding year. However, tonnage per man per day increased from 12.83 tons in 1960 to 13.87 tons in 1961, owing partly to the increased tonnage produced by continuous mining machines. Also, the percentage of total production mined by stripping and by augers increased slightly. Production.-The output of bituminous coal and lignite in the United States in 1961-403 million tons-was 3 percent less than the 416 million tons produced in 1960. Production was retarded in 1961, owing largely to the business recession and reduced exports.

Jan 1, 1962

By Donald J. Barnes

Gold was found in samples collected from Pleistocene and Holocene stream and terrace deposits. Approximately 15,000 cu yd (11,400 cu m) of small and discontinuous terrace and stream gravel deposits in the study area are composed of material derived from sedimentary and granitic rocks. The detritus is subangular to subrounded, and poorly sorted, ranging from boulder to sand size. Gold values in samples collected averaged 8.2 cents per cu yd (gold value of $500 per oz). Pan concentrates and rock chip samples collected from reported mineralized zones showed an absence of economic minerals. Stream placer deposits are uneconomic. No potential was observed for metallic or nonmetallic minerals in the La Panza study area. No potential exists for gas, oil, or coal resources.

Jan 1, 1981

By Michael J. Pazuchanics, Thomas J. Fisher, John J. Sammarco, Jeffrey H. Welsh

This report (An Introduction to Safety) is the first in a nine-part series of recommendations addressing the functional safety of processor-controlled mining equipment. It is part of a risk-based system safety process encompassing hardware, software, humans, and the operating environment for the equipment's life cycle. Figure 1 shows a safety framework containing these recommendations. The reports in this series address the various life cycle stages of inception, design, approval and certification, commissioning, operation, maintenance, and decommissioning. These recommendations were developed as a joint project between the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration. They are intended for use by mining companies, original equipment manufacturers, and aftermarket suppliers to these mining companies. Users of these reports are expected to consider the set in total during the design cycle. • 1.0 Safety Introduction.—This is an introductory report for the general mining industry. It provides basic system/software safety concepts, discusses the need for mining to address the functional safety of programmable electronics, and includes the benefits of implementing a system/software safety program. • 2.1 System Safety and 2.2 Software Safety.—These reports draw heavily from International Electrotechnical Commission (IEC) standard 61508 and other recognized standards. The scope is "surface and underground safety mining systems employing embedded, networked, and non-networked programmable electronics." System safety seeks to design safety into all phases of the entire system. Software is a subsystem; thus, software safety is a part of the system's safety. • 3.0 Safety File.—This report contains the documentation that demonstrates the level of safety built into the system and identifies limitations for the system’s use and operation. In essence, it is a "proof of safety" that the system and its operation meets the appropriate level of safety for the intended application. It starts from the beginning of the design, is maintained during the full life cycle of the system, and provides administrative support for the safety program of the full system. [ ]

Jan 4, 2001

By Edward A. Mihok

This paper presents plant design and cost estimates for limestone treatment of acid mine water covering a wide range of quality and quantity conditions. The treatment process consists of limestone neutralization, aeration, solids settling, and concentration. The design criteria for the various operation functions are based on pilot plant performance, laboratory data, and established mine water treatment standards. Unit costs have been assumed and are related to general market prices and conditions. These estimates serve as preliminary indicators of what it would cost to construct and operate a mine water treatment plant.

Jan 1, 1970

By R. D. Leitch

"INTRODUCTION This report is another of the series on the effect of drouth and low water on the pollution of streams by coalmine drainage. A previous report3 dealt with work on Bennett Branch of Sinnanahoning Creek, Pa. This report deals with the results obtained during a similar study of Black Lick Creek, Two Lick Creek, and Yellow Creek. All of these belong to the same drainage system. Two Lick Creek is a tributary to Black Lick Creek, and in turn Yellow Creek is a tributary to Two Lick Creek, as shown in Figure 1.Black Lick Creek was of such a volume that a seasonal investigation was not entirely feasible. Yellow Creek was found to have mines only near the mouth, except a few of status unknown to the writer at the extreme head-waters, and the stream was also more or less inaccessible for regular and frequent sampling. Two Lick Creek was found to be most suitable of the three.ACKNOWLEDGMENTThe work reported has been carried on under the direction and with the advice of Dr. R. R. Sayers, chief, health and safety branch, and W. P. Yant, supervising engineer, Pittsburgh Experiment Station."

Jul 1, 1931

By M. J. Spendlove, P. P. Zapponi

"INTRODUCTION In carbothermic processes for the production of magnesium, magnesium oxide is reduced by carbon according to the following equation:(1) MgO + C = Mg(g) + CO.The reaction is virtually complete at temperatures above 2,000° C. but reverses rapidly at somewhat lower temperatures. To produce magnesium by this reaction, therefore, it is necessary to cool the gas very rapidly to a temperature at which the rate of the reverse reaction becomes negligible. Several media for quenching the gas have been proposed, among which are hydrogen, natural gas, liquid hydrocarbons, and molten metals of low melting point.The results of a preliminary investigation on the use of molten lead as the quenching medium are summarized in this report. The work was done in 1941, when the threat of war made it imperative to investigate every process that offered possibilities for rapid expansion of domestic production of magnesium. Although the results were encouraging, other processes appeared to offer better prospects for immediate wartime development, so the work was not continued. Shortly before the investigation was completed, several patents on the use of low-melting metals for absorption of magnesium vapors appeared, 4/"

Jun 1, 1947

By Oliver Bowles

"The introduction into mines, quarries and manufacturing plants of machines and tools operated by compressed air has revolutionized methods of operation to an extent comparable only with that occasioned by the invention of explosives and the utilization of electricity. The use of compressed air in pneumatic tools, in rock drills, and for the operation of pumps and other machinery is well known to most miners and quarrymen, but its application as a substitute for explosives for breaking rock in a few granite quarries has received little publicity.In the region of Lithonia, a few miles from Atlanta, Georgia, is a dome of massive granite used widely for building stone and for paving blocks. The most remarkable structural feature of the granite is the absence of joints and sheeting planes. The term ""joints"" is applied to open fractures that commonly occur in rocks, usually vertical in direction or nearly so, and spaced from a few inches to several feet apart. On the Lithonia granite outcrop, however, one may walk over the bare rock surface for hundreds of feet without finding any indications of a joint, ""Sheeting planes"" are open fractures at various levels, approximately parallel with the rock surface. The presence of such planes when spaced several feet apart greatly facilitates quarrying, and where absent, as at Lithonia, the necessary fractures must be made artificially.The forcing of artificial sheeting planes is accomplished as follows: Two holes of about 3-inch diameter arc drilled close together and to a depth of about 8 feet. Two men work at these holes all summer, and sometimes part of a second summer. A very small charge of black blasting powder, not more than a spoonful, is placed in each hole, tamped with clay, and the charges are fired simultaneously with an electric battery. This starts a small fracture running outward from the bottoms of the holes. There is in most granites one direction of easy splitting known among quarrymen as the ""rift"", and as the rift direction in the Lithonia granite is horizontal the fracture follows a horizontal plane,"

Aug 1, 1920

By R. Pakalnis, C. A. Dreesbach, L. A. Martin

Instrumented cable bolts developed at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health were used in conjunction with existing ground control systems to monitor rock mass loads at Tg Soda Ash’s trona mine, Granger, WY. Axial and shear loads were determined to levels of strain gauge accuracy of ±5 N or ±5 microstrain. These gauges were embedded in a remanufactured king wire that replaced the conventional king wire. Cable bolt performance, quality of grout, and installation techniques were also assessed. By using instrumented cables, a mine operator can determine axial load along the cable at predefined gauge locations. These data provide necessary input for an operator to design a safer working environment for miners.

By James C. Ault, Walter W. Kaufman

This Bureau of Mines manual for design of surface mine haulage roads covers such aspects of haulage road design as road alignment (both vertical and horizontal), construction materials, cross slope, and drainage provisions. Traffic control and design of proper lane widths to promote safe vehicle movement are included, as are suggested criteria for road and vehicle maintenance and for runaway vehicle safety provisions. The aim of this publication is to provide those involved with surface mine haulage road design with a complete manual of recommended practices that, if implemented, will promote safer, more efficient haulage routes.

By John J. Sammarco, Edward F. Fries

This report (Independent Functional Safety Assessment 4.0) is the fifth in a nine-part series of recommendations addressing the functional safety of processor-controlled mining equipment. It is part of a risk-based system safety process encompassing hardware, software, humans, and the operating environment for the equipment’s life cycle. Figure 1 shows a safety framework containing these recommendations. The reports in this series address the various life cycle stages of inception, design, approval and certification, commissioning, operation, maintenance, and decommissioning. These recommendations were developed as a joint project between the National Institute for Occupational Safety and Health and the Mine Safety and Health Administration. They are intended for use by mining companies, original equipment manufacturers, and aftermarket suppliers to these mining companies. Users of these reports are expected to consider the set in total during the design cycle. • 1.0 Safety Introduction.—This is an introductory report for the general mining industry. It provides basic system/software safety concepts, discusses the need for mining to address the functional safety of programmable electronics (PE), and includes the benefits of implementing system/software safety program. • 2.1 System Safety and 2.2 Software Safety.—These reports draw heavily from International Electrotechnical Commission (IEC) standard IEC 61508 [IEC 1998a,b,c,d,e,f,g] and other standards. The scope is “surface and underground safety-related mining systems employing embedded, networked, and nonnetworked programmable electronics.” System safety seeks to design safety into all phases of the entire system. Software is a subsystem; thus, software safety is a part of the system’s safety. • 3.0 Safety File.—This report contains the documentation that demonstrates the level of safety built into the system and identifies limitations for the system’s use and operation. In essence, it is a “proof of safety” that the system and its operation meets the appropriate level of safety for the intended application. It starts from the beginning of the design, is maintained during the full lifecycle of the system, and provides administrative support for the safety program of the full system. • 4.0 Safety Assessment.—The independent assessment of the safety file is addressed. It establishes consistent methods to determine the completeness and suitability of safety evidence and justifications. This assessment could be conducted by an independent third party. • 5.0 Safety Framework Guidance.—It is intended to supplement the safety framework reports with guidance providing users with additional information. The purpose is to assist users in applying the concepts presented. In other words, the safety framework is what needs to be done and the guidance is the how it can be done. The guidance information reinforces the concepts, describes various methodologies that can be used, and gives examples and references. It also gives information on the benefits and drawbacks of various methodologies. The guidance reports are not intended to promote a single methodology or to be an exhaustive treatment of the subject material. They provide information and references so that the user can more intelligently choose and implement the appropriate methodologies given the user’s application and capabilities. [ ]

Jan 5, 2003

Provide sound battery safety guidelines for mine workers who maintain mobile surface mining equipment. Approach Battery-related accidents account for about 5 percent of all nonfatal disabling injuries in coal and metal nonmetal surface mines. These accidents occur despite the fact that appropriate battery safety technology (maintenance-free batteries, cable removers, fault detectors, hot-jumping systems, etc.) exists. Mine operators are not always aware of the safety measures that could be taken because this safety information is widely scattered in numerous unrelated technical reports, vendor brochures, and journal articles. A literature search of these reports and a review of relevant industry standards, handbooks, and references on battery safety, followed by discussions with mining company and MSHA personnel, provided the Bureau of Mines with the background necessary to develop procedures for proper and safe battery usage. These procedures were condensed and written in nontechnical language to serve as guidelines in assuring battery safety during maintenance of mining equipment.

Jan 1, 1986

By V. Rajaram, S. Bhattacharya, M. F. Dunn

During a mine fire or other emergency, it may be desirable to reverse the airflow in order to provide an escapeway or to isolate a fire. Also, (in colder areas, the airflow may be reversed to prevent ice buildup. When reversing main mine fans, the mine operator usually does not know what operating characteristics of flow and pressure to expect. Laboratory a field tests of vane axial main mine fans in the 7- to 9-ft diameter size range were conducted to establish forward and reverse performance characteristics under controlled conditions and at typical mine installations. The data obtained suggest that reverse performance characteristics are dependent upon the blade angle and the hub to tip ratio. There is also evidence that reverse performance can be predicted for a family of blade angles and a given hub to tip ratio. Generally, quantity of air is 30% to 65% less in reverse than when operating in the normal forward mode.

Jan 8, 1983

"It is evident that the incidence of coal worker's pneumoconiosis (CWP) or black lung disease varies in different coal producing regions of the United States. Many people have hypothesized about the reasons for the differing occurrences. Because underground coal mining involves many mining methods under changing geological conditions, several factors may be involved in contracting CWP such as: the amount of quartz in the respirable dust, the trace elements in the respirable dust, the rank of the coal that produced the respirable dust (bituminous, anthracite), the amount and size of respirable dust, etc.Recognizing the uniqueness of underground coal mining and CWP, research investigations involving seam characteristics, mining system and worker position are being conducted in the center to establish standard procedures for characterizing some coal properties that may be involved in workers contracting CWP. This has been accomplished by the in-mine sampling of airborne dust at various worker locations and mining system configuration and by performing laboratory analyses of mined material (coal and rock) taken from the mines. (FIGURE 49 and 50)The investigations includes a method of classifying coal seams according to their potential to generate respirable dust. It includes statistical analyses of the size and locational variations of the elemental compositions of respirable coal mine dust in operating underground mines from seams located in the eastern, midwestern, and western United States, and is currently completing research which is investigating the relationship between the elemental compositions of respirable dust sampled near a continuous-mining machine and a laboratory-produced respirable dust."

Nov 1, 1988

By R. H. Storch

This report describes work done as part of a Bureau of Mines program to appraise the titanium-mineral resources of Idaho. The work included both field reconnaissance and a spot churn-drilling program. Much general information was available, as a result of earlier work done under the Western Radioactive Minerals Exploration Program conducted between 1950 and 1954 by the Bureau of Mines for the United States Atomic Energy Commission. This particular exploration provided data as to the quantity of ilmenite (TiFe03) and accessory black-sand mineral concentrates in a number of placer deposits; however, at that time no tests were made to ascertain if the ilmenite was of marketable grade. The spot churn drilling was begun in the Gold Fork area of Long Valley, Valley County, Idaho (fig. 1), in August 1956 and was completed during October of the same year. Eleven holes (designated as the GF series on fig. 2) 35 to 45 feet in depth, aggregating 425 feet, were completed during this period. Data from other exploration drilling in 1951 was used in this report. The 13 holes in the G series shown in figure 2 were drilled by the Bureau of Mines for the United States Atomic Energy Commission; the 7 holes of the DH series were drilled by the Bureau of Reclamation. The 20 holes, ranging from 16 to 140 feet in depth, totaled 1,625 feet. The combined number of all samples recovered was 422. Those taken in 1956 were composited for each drill hole and sent to the Bureau of Mines laboratory in Albany, Oreg., for analyses.

Jan 1, 1958

By Douglas C. Peters, Valois R. Shea-Albin, Dennis R. Dolinar

An accurate assessment of the vertical stress on a coal seam at depth is important for mine design. Vertical stress calculation techniques presently available either are not sufficiently accurate or cannot handle complex surface topography. Therefore, the U.S. Bureau of Mines developed a computerized method to calculate vertical stress exerted on surfaces at depth that includes the effect of topography. Two input data sets are required: a digital elevation model containing topographic elevations and a coal seam file defining coal seam elevations at depth. Boussinesq's equation then quantifies the vertical stress resulting from topography. The computerized method was tested on a coal seam overlain by a complex topography where a vertical stress map encompassing several square miles was produced. Results show that depth mitigates the affects of surface topography, while the coal seam topography has a direct effect on the vertical stress. In comparison to the computerized method, the direct stress method overestimates stress under hills and underestimates stress under valleys. The largest difference between the two methods occurs under the steepest topographic relief. A limitation of the computerized method is that stresses cannot be accurately determined near an outcrop.

Jan 1, 1992

By Kathleen J. D?Amico

THIS SUMMARY is identical to the summary given in volume III of this series of mineral production in the United States (including Alaska and Hawaii), its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico and of the principal minerals imported into and exported from the United States. For further details on production see commodity and area chapters. A summary table comparing world and United States mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed "mine output." It usually refers [ ]

Jan 1, 1958

Avoid accidents that can occur when applying belt dressing from an aerosol can, particularly when can pressure has dropped or when spraying against wind. Approach Use a garde-type sprayer. How It Works Commercially available garden-type sprayers can be used for applying conveyor belt dressing from 12 feet away, or more. Pressure is easily raised and maintained at about 50 psi. Most sprayers have a hand pump, but a battery-powered cordless model is also available. Garden-type sprayers are available in various sizes from 11/2 to 18 gallons, with the larger models wheel mounted. The 3-gallon model evaluated by the Bureau has a shoulder carrying strap, which gives additional safety advantages. Use of the strap frees both hands for climbing ladders or holding onto catwalk rails. When spraying, one hand can remain on a handhold to lessen the chances of touching a moving belt.

Jan 1, 1980