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By Winton Gale, David Oyler, Jinsheng Chen, Christopher Mark

The National Institute for Occupational Safety and Health’s (NIOSH) Pittsburgh Research Laboratory (PRL), RAG Pennsylvania and Strata Control Technologies of Australia have collaborated to conduct an extensive study of roof bolt strata interaction at the Emerald mine in Southwestern Pennsylvania. The primary goal of the project was to obtain detailed data on the interaction between the mine roof and the support elements for use in modeling studies. The study site was a longwall tailgate subjected to high horizontal stress. Three arrays of instruments were installed at the site, one in the tailgate entry and two in an adjacent crosscut. Pumpable concrete cribs were present in the tailgate array, and cable bolts were installed in one of the crosscut arrays. The instruments included mechanical and sonic extensometers for measuring roof movement, instrumented roof bolts, and three-dimensional roof stress cells. The study was ultimately successful in determining the magnitude of the horizontal stress concentration, the height of roof failure and the roof failure sequence, and the loading history of the primary roof supports.

A symposium was held on January 30 and 31, 1973, at Pittsburgh, Pa., to review the state-of-the-art in designing and utilizing diesel-powered equipment in underground mining. The Health and Safety Activity of the Bureau of Mines sponsored the symposium with major assistance from the following four participating organizations: The American Mining Congress J. Allen Overton, President The United Mine Workers of America Arnold R. Miller, President The National Independent Coal Operator's Association Cloyd D. McDowell, President The Bituminous Coal Operators' Association, Inc. Guy Farmer, President Seventeen papers were presented during four half-day sessions devoted to the general subjects of the diesel engine, the place of the diesel in underground mining, health protection using diesels underground, and maintaining safety of diesels underground. Eleven of the speakers were from industrial organizations here and abroad; one represented the Provincial Government of Nova Scotia; two were with the Department of Health, Education, and Welfare; and three reported on Bureau of Mines work related to diesels.

Jan 1, 1975

By Eugene H. Skinner

The U.S. Bureau of Mines conducted experiments on the use of lightweight concrete in the density range of 100 Ib/ft3 for liners in underground mines. Three test sections were completed: a monolithic, portal-type structure with integral walls and arch constructed aboveground; an underground test section constructed in a mine drift using plywood forms; and a second section constructed in a drift using an air-supported formwork. The lightweight concrete in the two underground test sections was placed using piston pumps and a slickline. Fiber reinforcement was added to the concrete in the mine sections without any apparent problems with either pumping or placement of the concrete. In another experiment, the Bureau and Hecla Mining Co., Mullan, rD, used lightweight concrete in the density range of 25 Iblfe to replace timber blocking in a raise preparation structure. Other experiments are described in which low-density, lightweight concrete blocks were produced for mine ventilation doors, stoppings, and barricades. Other mine uses reviewed include pillars and collapsing beams. An advantage of low-density concrete is that it will display up to 50% deformation at a constant yield stress. These hlllovative concepts in deformable concrete lining systems will aid mine operators by decreasing capital and maintenance costs, increasing the available space in underground haulageways, and providing productivity gains and improved resource recovery in the soft, caving, squeezing, or bursting grollnu conditions often found in deep mines.

Jan 1, 1989

By S. M. Shelton, A. L. Engel

"This report presents the results of investigations of ore-testing projects assigned to the Ore-Dressing Section, Metallurgical Division, Bureau of Mines, at the Mississippi Valley Experiment Station, Rolla Mo. During the fiscal year ended June 30, 1941.The manner of approving ore-testing projects has been explained in a previous reports. 4/ The testing procedures likewise have been described. 5/The treatment methods described are based upon laboratory experiments with small amounts of sample and naturally are subject to the inherent, normal, limiting conditions of such procedure. It is not intended to describe treatments in detail, but rather to indicate applicable methods. Local operating conditions, when the laboratory results are applied to plant operations, may require further study. Large-scale pilot-plant tests should be made before commercial operations are begun, so that translation from the experimental stage will yield satisfactory results."

Mar 1, 1942

This report, 27th in a continuing series1, describes Bureau of Mines research and technologic work on coal and related investigations during 1962. While the brief discussion in each section of the report presents only the highlights of Bureau work during the year, details of many investigations can be found in publications cited in this text. Other work, reported here for the first time, will be covered in greater detail in later publications. Recent trends in coal research and technology both at home and abroad were reviewed in several publications2. Bureau research, as in the past3, continued to stress improved methods of mining, preparing, processing, and using coal. The program included a wide variety of applied and basic studies for developing information useful to the coal mining industry and the coal consumer while promoting wise conservation and utilization of our coal resources.

Jan 1, 1963

By D. E. Sullivan

The Bureau of Mines investigated the availability of potash from 68 mines and deposits in 12 market economy countries (MEC's) containing, at the demonstrated resource level, approximately 11.7 billion metric tons (mt) of potash in assay terms of contained K2O; K2O as used by industry as a standard of comparison for the different forms of potash. These resources include almost 190 million mt in the United States, 9.63 billion mt in Canada, approximately 430 million mt in Western Europe (France, Federal Republic of Germany, Italy, Spain, and the United Kingdom), 1.24 billion mt in the Middle East (Israel and Jordan) and over 220 million mt in other countries (Brazil, Chile, and the Congo). This analysis his determined that future production of potash in MEC?s will most likely continue to be from the large resources associated with producing operations in Canada. Based solely on the demonstrated resources included in this study, potash mining in the United States would decline while overseas production from MEC's can continue into the next century at near current production levels. However, timely development of new or inferred resources would offset any such decline. Producing mines in Canada have the resources to increase and maintain increased production well into the next century. For U.S. potash users, Canada is a long-term stable and secure source.

Jan 1, 1986

By G. L. Oldright

As sponge iron is much like porous, coarse sand, it is a tempting material to use in place of coarse scrap iron as a precipitant of metals, for scrap iron is relatively awkward to handle and exposes only a small amount of surface to pregnant solutions. The results of the experiments described in this bulletin are largely a record of the behavior of sponge iron as a precipitant of lead and copper under laboratory conditions comparable to those that would obtain in a commercial plant were it attempted to secure the maximum contact of surface between solution and precipitant. Physically, the study is largely one of the rates of diffusion of the metal ions in the solutions and through the metallic coatings surrounding the sponge iron particles. The practical objectives are to remove completely the valuable metals from solution and at the same time to obtain a precipitate of good grade. In order to fulfill this latter requirement, the precipitant should be almost completely consumed. These practical ends are usually secured by having the two substances involved pass each other counter-currently-that is, in such a manner as to have the strongest precipitant in contact with the most impoverished solution, and vice versa. EXPERIMENTS WITH LEAD SOLUTIONS In nearly all of the schemes involving the leaching of lead from its ores the metal has been put into solution as the chloride, and fairly concentrated liquors have been employed. The solubility of lead under such conditions is comparatively small at best; the hot pregnant liquors from which the metal is to be precipitated are then made nearly saturated with respect to lead, and only a very small amount of acid is used. Therefore it was not as necessary to learn the behavior of the sponge iron in precipitating lead from solutions of widely differing composition as to learn under what conditions, and with what mechanisms, this precipitation might be carried out most readily.

Jan 1, 1928

By H. C. Fuller

This paper discusses 105 production runs at Boulder City, Nev., in which titanium metal was made in 200-pound batches. It describes the equipment and techniques used in preparing raw material, the reduction process, and the removal of the reaction mass from the reaction vessel. Also, some data on man-hour requirements are presented. The main emphasis was on producing ductile-grade titanium and developing a standard procedure for obtaining a consistently pure product. Some departures from techniques used before were found to be desirable. The most important of these was the use of a sealed room with a controlled dry atmosphere in which the reaction vessel was opened and the reaction mass removed. This minimized the moisture taken up by the magnesium chloride in the reaction mass, and it could be purified successfully by vacuum distillation. Using the dry room also made it possible to leave al-inch shell of the reaction material on the walls of the vessel, which lowered the iron contamination and eliminated the labor and time-consuming job of cleaning the vessel after each reduction. Another change was lowering of the temperature during reduction to 750° C. instead of 850° C. This was found to give good results more consistently. The first poke to break the crust during reduction was eliminated, as it was found to be unnecessary and only added more work and was another possible way of introducing air. A rotating feed arm was installed in the reaction vessel to distribute the titanium tetrachloride over a larger area and, thus, prevent local overheating. The process, conducted in a batchwise manner as described and followed by good purification and fusion, produces a metal adequate in quality for nearly all purposes.

Jan 1, 1952

By Worthen Bradley

This paper describing the metallurgical practice and costs at the reduction plant of the. Sulphur Bank Syndicate, Clearlake, Calif., is one of a series of papers on the treatment of ores being prepared by the Bureau f Mines. The reduction plant and mine of the Sulphur Bank Syndicate are on the eastern shore of Clear Lake, in Lake County, Calif., 4 miles from the town of Clearlake and 125 miles north of San Francisco.

Jan 1, 1931

By James C. Barker

Yttrium and rare-earth element. pegmatite dikes are associated with a peralkaline granitic and nephelene syenite complex near Dora Bay on southern Prince of Wales Island. Mineralized dikes were mapped and sampled during USBM investigations in 1987 and 1988. Coarse-grained pegmatite dikes, which emanated as late-stage magmatic fluids from the intrusion, further evolved into vein-dikes and ultimately silica-rich veins. The dikes can be traced up to two miles along a north-south zone. Lithophile elements exhibit a pronounced zonation in vein-dikes and veins that are distal to the Dora Bay complex with increasing values correlating with increasing distance from the complex. The pattern of mineralization suggests very late stage magmatic fluids containing the incompatable lithophile elements were injected into a preexisting north-south fracture zone. REE mineralogy exhibit fine-grained intergrowths of principally thalenite and bastnaesite with lessor monazite and eudialyte. Euxenite contains most of the columbium values and zircon is commonly associated with the dikes. Estimates of inferred and hypothetical resource tonnage range from 1.7 X 1C6 to 8.5 X 106 st for two deposits. Contained RED (including yttrium) averages 0.5 pct and ranges up to 2.0 pct. Deposits are of polymineralic composition and about half of this resource comprises the heavy yttrium subgroup.

Jan 1, 2011

By Robert S. Schechter

A minitest of the new potassium chloride-potassium carbonate two-stage in-situ uranium leach process has been carried out at the Intercontinental Energy Corporation (IEC) Zamzow project site in South Texas. Substantial quantities of high concentration uranium were produced indicating the viability of the leach solution. The test results yield information regarding the reservoir dispersivity, the average cation-exchange capacity of the formation, and the distribution coefficients describing cation-exchange reactions. The test also indicates permeability anisotropy and the existence of disturbed flow fields.

Jan 1, 1985

"D bed, Ky., coaL, washing characteristics RII 5140coking coal, reserves, estimate RI 5037Pa., coal, washing characteristics RI 4834, 4941D bed mine, Ky., coal, washig characteristics"

Jan 1, 1960

By Michael A. Trevits

Since the promulgation of the MINER Act and the follow-up changes to the regulations governing mine seal construction and maintenance, mine operators must be acutely aware of the atmosphere in sealed mine areas and prepared to deploy control technologies when the conditions are warranted. On Site Gas Systems1 in Newington, Connecticut was awarded a contract by the National Institute for Occupational Safety and Health (NIOSH) to construct a novel in-mine nitrogen (N2) generation plant using pressure swing adsorption (PSA) technology. PSA technology utilizes carbon molecular sieve material and pressure to adsorb oxygen (O2) molecules while allowing N2 molecules to pass through the sieve material. The prototype PSA unit was tested at the NIOSH Safety Research Coal Mine (SRCM) where a 62,000 ft3 area of the mine was rendered inert during a series of two tests. The resultant data were then used to construct a CFD simulation of both injection tests. In addition, O2 depletion and gas leakage rates were quantified in the model and were compared to actual values. Once the model was calibrated, the sealed mine area was doubled and simulations were made with various injection rates and injection site locations to determine the impact on the time needed to render this area inert. This paper presents an overview of the PSA plant, the details of the gas injection tests and CFD modeling work.

Jan 1, 2010

By W. S. Landers

This report presents a detailed study of low temperature, entrained-bed carbonization of an Australian coking coal. The coal studied was high-volatile B bituminous from the Foybrook mine, an open-cut operation in the Liddell seam, New South Wales, Australia. Carbonization was conducted in an 8-inch diameter, continuous vertical reactor at several temperatures from 960° to 1,300° F. It was demonstrated that this bituminous coal can be carbonized within this temperature range to produce tar and a nonagglomerated char, without prior oxidation or char recirculation. Carbonization rates from 138 to 287 lb/hr (as-carbonized basis) were investigated. It was found that the carbonization temperature and the air-to-coal ratio must exceed minimum values to insure continuous operation. At the higher air-to-coal ratios employed, all or most of the carbonization heat was provided by internal combustion with air in the reactor. At the lower air-to-coa1 ratios, part of the heat for carbonization was supplied externally. On the moisture-and ash-free basis, the yield of tar plus light oil ranged from about 26 to 44 gallons per ton, and the char yield ranged from approximately 1,160 to 1,370 pounds per ton. The heat in the gas ranged from about 900 to 3,000 Btu/lb of moisture-and ash-free coal. Carbonization product yields correlated well with air-to-coal ratio and carbonization temperatures. The volatile matter in the char was found to be temperature dependent. At 1,300° F carbonization, the volatile matter in the char was 8.7 percent (dry basis), whereas at 9600 F carbonization, the residual volatile matter was about 16 to 18 percent (dry basis).

Jan 1, 1965

By W. M. Nabors

As part of a program to promote conservation and efficient utilization of petroleum resources, Bureau of Mines engineers at the Morgantown (W. Va.) Petroleum Research Laboratory are studying secondary oil-recovery projects in the Appalachian region. The increasing demand for petroleum and its products and the increasing cost of exploratory drilling tend to emphasize the importance of improving the recovery of oil from known petroleum reserves. Published reports setting forth the pertinent facts of these operations may help others to profit by the experience. This report presents the results of a study of secondary-recovery methods used in West Virginia by the Piedmont Oil and Gas Co., the Ryan Oil Co., and Water floods , Inc., on their Roane County leases in the Walton and Clover Rush Run pools. The principal oil-producing horizon underlying the area studied is the Big Injun sand, at approximately 2,000 feet. The sand is often referred to as blanket sand because it underlies much of the State and is oil-productive in many localities. Most of the pools in the area were discovered during 1907 to 1910 and were similarly developed and operated.

Jan 1, 1960

By Elaine T. Bowers

The Sunnyside single-entry project pioneered the use of single entries for longwall development in this country. During the 10-year course of the project, an immense amount of information was gathered. Over three miles of entries were observed primarily through instrument groupings placed in strategically located areas or "rooms." Nearly 1,200 instruments were monitored to gain information on the behavior of coal entries during development stages and through the mining of two longwall panels. This was one of the most extensively documented projects undertaken by the Bureau, The data gathered has a great potential for scientific research especially in the area of longwall mining. This Bureau of Mines report presents the ground control data gathered, in the form of computerized plots. Roof-to-floor deformation and load on cribs and roof bolts make up the bulk of the data, which is presented as load or deformation versus time. The plots are organized, generally, by the three main entries involved and, specifically, by the individual areas or rooms in those entries. No major attempt will be made, in this paper, to analyze the data other than to identify its source arid its history.

Jan 1, 1983

By O. H. Metzger

This is one of a series of capers being published by the Bureau of Mines on gold mining A the Western States. It describes the production of gold in the principal mining districts of New Mexico. The material was gathered red on a trip through tale State in the summer of 1936. ACKNOWLEDGMENTS The author acknowledges the aid and cooperation of mine operators in all parts of the State, who willingly contributed all information requested. Geological reports of the Geological Survey and the New. Mexico Bureau of Mince were drawn upon freely for information; credit to individual paper, is given in the text.

Jan 1, 1938

By D. A. Paice

A portable calibrator to check tie trip setting of dc circuit breakers within an accuracy of +5% has been developed for the Bureau of Mines. It operates from a 300 volt dc trolley wire to provide controlled current pulses of 120 milliseconds duration and continuously adjustable from 1400 to 3600 A. These current pulses enable a breaker dc trip current to be determined and subject the contacts to full current rating. The equipment is simple to use and weighs 86 pounds. Connections are made with protected, clamp-on leads which are separately connected and weigh about 22 pounds. An accurate calibration procedure takes less than 5 minutes to complete.

Jan 1, 1978

By Michael J. Klishis

It was the goal of this project to develop training materials specific to two areas of the mining industry: (1) safe use and care of the self-contained self-rescuers, and (2) awareness and avoidance of electrical hazards. This report describes the development of the following training material: Instructor's modules for the OCENCO EBA 6.5, CSE AU-9A1, and PASS 700E self-contained self-rescuers; and a textbook, slide tapes, and accident case study scenarios for mine electricity, and a computer based instructional package on mine electricity and electrical hazards. The report concludes that additional efforts are needed in mine training and four recommendations are made: (a) tailor existing materials to fit specific mine sites, (b) develop and evaluate computer based instructional material, (c) develop parallel training materials for metal and non-metal mines and, (d) develop additional training materials for preparation plants and surface areas of underground mines.

Jan 1, 1985

By P. M. Ambrose, C. Travis Anderson, Cresap Moss, R. S. Dean

"MANGANESE METALMethods of PreparationMethods of preparing the manganese metal that has been used in chemical and metallurgical investigations have passed through a cycle. Most of the investigations made before the turn of the century used Moissan's pyrophoric manganese. 5/ This material was made by electrolysis into a mercury cathode and distillation in vacuo. It was essentially a pure material, and investigations in which it was employed (with proper precautions against oxida¬tion) led to accurate results concerning the intrinsic behavior of metallic manganese.An early investigation of the properties of ""Manganese-by-Mercury"" was made by M. Guntz. 6/ He prepared manganese by electrolysis of a concentrated MnCl2 solution with a mercury cathode. The manganese amalgam was pressed through chamois and distilled in vacuo (2 to 3 cm. of mercury) at 200°0., slowly rising to 250°0. Guntz recognized especially the decreased reactivity of manganese with increased temperature of mercury distillation. The most careful and com¬prehensive study of manganese made by this method is that of Kuh 7/ whose work unfortunately was never published in an accessible journal.Royce and Kahlenberg 8/ studied the electrode potential of manganese made by this method."

Nov 1, 1939