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By Reed. Donald F.

"Deposits of gray hematite occur in two districts in Talladega County, Ala., the Emauhee-Tallasochatchee and Weewoka, both in the vicinity of Winterboro, 50 miles east of Birmingham.The deposits were investigated by the Bureau of Mines in 1943 and 1944. Approximately 13,000 feet of diamond drilling was done and 6,000 linear feet of trenches excavated and sampled.A total of 13,000,000 tons of ore averaging 36 percent iron was indicated in all areas.A detailed discussion of each property investigated, drill logs, and sampling results are given in this report.In the work done in the Talladega County iron investigation, special acknowledgement is due to Paul M. Tyler, formerly regional engineer, Eastern Region, and Richard W. Smith, formerly district engineer, for aid and direction of the project; also to J. B. Clemmor, metallurgist, for diligent research work in the Southern Experiment station laboratory. All were members of the Bureau of Mines Staff.The project was conducted in cooperation with the Federal Geological Survey, whose field work was in charge of T.G. Andrews assisted by Brewster Baldwin. The able and valuable assistance of Andrews and Baldwin aided greatly in accomplishing the project.The areas investigated by the Bureau of Mines were in two districts: The Emauhee-Tallaseehatchee district, between Sylacauga and Sycamoer (marked B on fig. 1) and the Weeworka district, between Winterboro and Sycamore (marked A on fig. 1)."

Mar 1, 1949

By Fred N. Kissell

In This Chapter [Measuring the gas emission from the coal Methane at the top of the silo Methane at the load-out area and Actions taken after a silo explosion] Methane accumulations in coal silos have resulted in the occasional silo explosion. These can be quite violent and dangerous because coal dust adds to the strength of the blast. However, with the appropriate precautionary measures, methane accumulations in silos can be greatly reduced. Mine Safety and Health Administration (MSHA) regulations at 30 CFR2 77.201 require that the methane content in the air of any coal silo be maintained below 1.0 vol %.3 Also, MSHA requires that methane tests be conducted before any electrical equipment is energized, unless a continuous monitor capable of deenergizing the electrical equipment is used.4 Measuring the gas emission from the coal. The first necessary step in dealing with silo methane issues is to measure the gas emission from the coal going into the silo. Such measure-ments allow one to estimate the silo ventilation needs and permit a comparison with the methane controls used at other mines that have similar gas levels. The gassiness of the coal can be measured by taking conveyor belt grab samples.5 Matta et al. [1978] measured the gas emission from conveyor belt grab samples using a simple desorption test. To conduct the test, they collected several grab samples of coal, weighing a few pounds each, from the conveyor belt entering the silo.6 They then sealed the coal into an airtight sample container that was equipped with a valve and short hose along with a pressure gauge. Every few hours they opened the valve and bled the emitted gas into a water-filled graduated cylinder that had been inverted and placed in a pan of water (Figure 11–1). The results are shown in Figure 11–2.

Jan 6, 2006

By Linneas W. Laage

The purpose of this report is to document the fire experiments conducted at the Waldo Mine, NM during March 1990. The U.S. Bureau of Mines is concerned with improving and validating the predictive capability of the mine ventilation and fire simulator, MFJRE. To accomplish this, fire experiments were conducted at the Waldo Mine and temperature profiles were developed as functions of time and distance from the fire. These tests then provided data for verifying the heat transfer model in the MFIRE mine ventilation and fire simulator. An initial analysis of this data indicates that it will serve this purpose well. This report summarizes the data obtained during six fire tests at the Waldo Mine.

Jan 1, 1994

By Larry Patts, Jon Hummer, Jim Noll, Aleksandar Bugarski1, George Schnakenberg, Steve Mischler, Mike Crum, Shawn Vanderslice, Rick Anderson

This study is organized under the auspices of the Metal/Nonmetal Diesel Partnership formed by the National Institute of Occupational Safety and Health (NIOSH), the National Mining Association (NMA), the National Stone Sand and Gravel Association (NSSGA), the United Steel Workers of America (USWA) and the MARG Diesel Coalition. The ultimate objective of the study is to reduce the exposure of underground miners to diesel particulate matter (DPM) and gases, and to help in fulfilling the partnership’s goal of identifying technically and economically feasible controls to curtail particulate matter emissions from existing and new diesel powered vehicles in underground metal and nonmetal mines. The majority of current knowledge on the performance of the diesel particulate filter (DPF) systems and other control technologies is based on studies done under laboratory conditions, the results then being applied the results to on-highway vehicles. According to the best knowledge of the authors, only two comprehensive studies that were conducted recently at Noranda’s Bathurst Mining and Smelting Mine and International Nickel Company’s Stobie Mine under the sponsorship of the Diesel Emissions Evaluation Program [McGinn 2001, Bugarski and Schnakenberg 2001, Bugarski and Schnakenberg 2002] offered some insight into the problems associated with the deployment of modern DPFs to underground mining vehicles. The U.S. mining industry has expressed concern that this rather limited knowledge base is not sufficient to help them comply with the rule limiting DPM exposure of underground metal and nonmetal miners [30 CFR 57.5060 2001]. The partnership agreed that a series of comprehensive field evaluations of DPFs in several underground mines was needed to determine their viability of DPF systems and establish confidence in their performance. The first in this series of studies was the one conducted in Stillwater Mining Company’s Nye Mine, Nye, Montana. This study was conducted in two phases. The objective of the first phase was to establish the effectiveness of the selected technologies in reducing diesel emissions by using an isolated zone methodology. The objective of the second phase was to assess the effectiveness of diesel particulate filters in controlling the exposure of underground miners in actual production scenarios. As part of the first phase of the study a series of tests were conducted at Nye Mine from May 19, 2003 until May 30, 2003. The results of Phase I of the study are presented in this report.

Jan 1, 2005

By Charles L. Harness

The barite industry has made notable progress since the days when barite was used only as an adulterant in white-lead paints and the only method of mining it was with pick and shovel. The following chronological record may serve to show how this heavy white mineral has grown in importance in the national exonomy and at the same time to indicate development of methods for obtaining it. 1845. - Barite first, mined in Fauquier County, Va., for use as an adulterant in white-lead paints. 1850 (approx.). - French settlers 60 miles southwest of St Louis, Mo., discovered barite; called it "'tiff;' meaning white. It was mined and shipped to St. Louis for use in paint.

Jan 1, 1946

By M. Mahan, D. D. Blue, O. C. Garst, F. Fraas, L. Fink

"Early in World War II it became apparent that the known bauxite re- serves might not be adequate to supply the demands of the American aluminum-producing industry, as the transportation of bauxite from abroad to this country might easily be interfered with by hostile action. Consequently, the Bureau of Mines set up an intensive, well-integrated program for the production of cell-grade alumina from low-grade domestic ores. This pro-gram of investigation covered the production of alumina from clay, alumite, red mud, and other low- and marginal-grade ores. In line with the Bureau's usual policy of conservation of natural resources, it was decided that the investigation should be extended to cover the production of alumina and other valuable byproducts from aluminum dross.Statistical information showed that during the year 1943-44, an average of 2,900 tons of aluminum dross was generated monthly. This dross, after partial removal of free metal, had an average metallic aluminum content of approximately 9 percent. Some of this dross was produced by the melting of alloyed aluminum; but a large proportion 1,700 out of 2,900 tons - was generated by two producers of primary aluminum, and the dross did not contain an great proportion of alloying metals. Compared with dross from other sources, this 60 percent of the country's capacity can be assumed to have relatively uniform composition. Moreovcr, the problem of collection and distribution can be minimized because of the relatively small number of plants included in the organization of these two producers of virgin metal.Except for large pieces of metallic aluminum that easily can be mechanically separated for remelting, this dross has been discarded and scrapped. Inasmuch as chemical analyses show that the alumina content of dross is far higher-than ordinary ores - 111 percent alumina equivalent in dross compared to 57 percent alumina in bauxite - aluminum dross is a far richer source of aluminum than any known naturally occurring ores. The discard, of this waste material during the war and reconversion periods would be unsound economically. The work reported herein describes tests at the College Park Station of the Bureau of Mines on the recovery of metal, alumina, ammonia, methane, and abrasive-grade corundum from dross."

May 1, 1946

By John E. Lambert

Automatic control of drum head continuous mining machines was investigated as a means of reducing respirable dust generated and operator variabitity. Literature survey, manufacturer interviews and mine visits were the major information sources. Technically feasible automation concepts were Identified to control sump and shear rates, cutter head elevation limits and sumping distance. These are the elements of a programmed cutting cycle which maintains peak penetrating force on the cutter, to maximize depth of cut and therefore reduce dust generation. Based on the industry surveys, successful underground hardware demonstrations must be completed in order to stimulate the market demand for these advanced control features.

Jan 1, 1979

By Robert L. Lagace

A prototype adaptive volume control for the loudspeaker output of mine trolley carrier phones was designed, built, and tested in the laboratory and in a mine. This volume control senses, and adapts to, the ambient acoustic noise environment in such a way as to produce a loud sound output under noisy conditions, and a quieter output under quiet conditions, thereby producing an understandable and unstartling volume level under all noise conditions. The design approach, prototype hardware, and test results are described, and the device is shown to be feasible for in-mine operations. The circuit design principles are easily applicable to currently available mina trolley carrier phones. Recommendations for practical improvements are included. An in-mine experiment to assess the practical feasibility and utility of the dedicated wire technique for overcoming poor trolley carrier phone system performance was designed, performed, and evaluated. The technique involves the use of a single, low-loss, properly terminated auxiliary wire, placed in the rail haulageway, which allows signals to naturally couple to and from the trolley wire/rail transmission line, and thereby significantly decrease the overall signal attenuation rate on the trolley wire/rail line. The in-mine dedicated wire experiment, results, and conclusions are described, and the technique is shown to be a valid and practical one for significantly Improving carrier phone system performance in mines. Guidelines for the installation and use of the dedicated wire are provided. Recommendations are made for obtaining further practical information on its performance and utility. A second in-mine experiment to assess the feasibility and utility of the low-impedance (low-Z) line technique for overcoming poor carrier phone signal transmission in mines was designed, performed and evaluated. The low-Z line technique involves the periodic connection of shunt capacitors between the trolley wire and the rail to artificially lower the line characteristic impedance. This causes the low impedance shunt loads encountered across the trolley wire/rail line to be less mismatched to the line, thereby reducing the overall attenuation of carrier phone signals. The results of in-mine experiments performed along unenergized and fully operational sections of trolley wire/rail line are described. The experiments were designed to measure line parameter such as inductance and capacitance per unit length, characteristic impedance, and propagation phase velocity, in addition to signal strength versus distance behavior under normal and low-Z line conditions. The low-Z line technique is shown to be valid, but not as practical as the dedicated wire technique which is recommended as the most favorable for most coal mine applications.

Jan 1, 1979

By P. R. Jones

A computer program was written for the design of a shell and tube heat exchanger on a price optimum basis for the following conditions: (1) Triangular pitch; (2) single or multiple pass; (3) heating or cooling; (4) no change in phase; and (5) inside pumping costs immaterial. Price optimum design was obtained for four standard tube sizes and standard pitch. The inside pressure drop was fixed and outside pressure drop was computed for the optimum baffle spacing and when the baffle spacing equaled the shell diameter. Standard shells whose areas equaled or exceeded the required area were also listed. The program was made adaptable to various fluids and to various tube sizes and pitch by reading in many of the required data such as physical properties of the fluids, tube data, and standard shell data in tabular form.

Jan 1, 1968

By Daniel S. Witkowsky

The Pollution Prevention Act of 1990 provides few specifics to assist the non-fuel mining and mineral processing industries of the United States in achieving pollution prevention (P2) compliance. The U.S. Bureau of Mines (USBM) recognizes the absence of specific information to reduce pollution impacts from mining and mineral processing of hardrock and industrial minerals. Therefore, the USBM has prepared this publication to help reduce or eliminate environmental pollution and to assure the viability of these segments of the domestic mining industry. This report includes worksheets designed to help operators of mining and milling facilities to establish a P2 program. The report can also be used by citizen and environmental groups, State and local governments, and academia to gain an understanding of P2 as it relates to mining and mineral processing.

Jan 1, 1995

The mine surveillance and communication system hereafter described provides continuous local and remote monitoring of several parameters critical to normal mine operation at each of ten underground sites in the Bruceton Research Mine. The techniques employed are well proven and have been care-fully chosen to provide the best solution to the technical problems involved while giving special attention to economic considerations.

Jan 1, 1973

By Martin Hertzberg

This Bureau of Mines study concerns the use of the tube bundle method as a sensitive and reliable detector of mine fires. The method involves the pneumatic, sequential sampling of many points in a system through branching tube bundles that lead to a single analytic station of high sensitivity, good reliability, and convenient location. Two serious limitations inhibit its use: the relatively slow response times for long lengths of narrow sampling tubes and the wall-diffusion losses for submicrometer smoke particulates. These limitations were quantitatively evaluated by measuring tube transit times and smoke particulate transmissions as a function of tube length, diameter, and pressure drop. The comparison of the data with theory offered the challenge of extending the classical, incompressible flow solutions to the two compressible cases: isothermal and adiabatic. New equations were derived for these cases, and the measured transit time data gave reasonable agreement with calculated solutions in both the laminar and turbulent regimes. The measured transmission losses of smoke particulates from several combustion sources compared favorably with those expected from Brownian diffusion losses to the interior walls of the sampling tubes. Traveltime and smoke transmission graphs are provided and, pump power requirements are estimated.

Jan 1, 1976

By R. E. Chaney

This report summarizes the research on the Strategic and Critical Materials Program tasks conducted at the Idaho National Engineering Laboratory (INEL) between Mdy 1983 and April 1984. The work is divided into two areas: 1. Production Technologies - Tasks directed at developing advanced extraction technologies ? Biologically-Assisted Minerals Processing ? Metal/Gas Reactions and Thermal Plasmas ? Dehydration of Aluminum Chloride Hexahydrate. 2. Conservation/Substitution Technologies - Tasks directed toward establishing the technical processing base which will permit the use of advanced materials ? Joining of Rapidly Solidified Alloys (RSA) ? Joining of Silicon Nitride-Based Ceramics ? Nondestructive Evaluation of Ceramic and RSA Joints and Materials.

Jan 1, 1984

By Nicholas T. Zilka

Mineral resource studies by the Bureau of Mines indicate three areas within the Selway Bitterroot Wilderness have mineral resource potential. Regional studies suggest that a granitic stock on the south side of the Wilderness has high potential for a Climax-type stockwork molybdenum deposit (pl. 1, no. 8); but detailed surface investigations failed to recognize a deposit. The Elk Summit area on the north side of the Wilderness contains subeconomic resources of columbium (niobium)-bearing ilmenite in placers (p1. 1, no. 19). Subeconomic silver-copper-lead resources occur in a vein on the northeast side of the Wilderness at the Clift Mine (pl. 1, no. 2-5). The study area has no known deposits of oil and Haas, coal, geothermal resources, or other energy-related commodities.

Jan 1, 1982

By Daniel I. Carey

Current and potential dragline reclamation usage was evaluated for the U.S. coalfields based on data gathered and analyzed during field surveys, literature reviews and contacts with manufacturers. It was concluded that current mining plans have been adapted to federal and state strip mine and reclamation laws in ways which limit the potential for dragline reclamation systems at active mine sites. At abandoned conventional contour mine sites in steep-sloping areas such as central Appalachia, however, it was found that dragline reclamation systems have great potential application and may be the only practical solution to many reclamation problems. Alternative dragline systems were examined for restoring abandoned sites, and it was concluded that a tower excavator system offered superior characteristics and should be evaluated and developed under field conditions. A testing program was developed to provide a framework for the monitoring and analysis of cost, production and environmental data during a field demonstration of a tower excavator system.

Jan 1, 1981

By G. M. Potter, J. B. Rosenbaum, Masami Hayashi

Most Japanese copper smelters are located in areas of concentrated industrial activity and high levels of atmospheric pollution. A review of unofficial sulfur dioxide emission control data from major Japanese smelters shows capture of 91 to 99.7 percent of the sulfur in the smelter feed. The bulk of Japanese smel ting capacity was constructed in the last 10 years. Six of the major sme lters use flash furnaces, and two use reverberatory furnaces. A prototype three-furnace continuous system is in use as a parallel train with reverberatory furnaces at one smelter. Most of the sulfur dioxide is manufactured into sulfuric acid. The remainder is captured by gas scrubbers that yield gypsum and sodium salts. Ready markets exist in Japan for the acid and other su lfur byproduc ts.

Jan 1, 1967

By R. S. Dean

A large metallurgical experiment station at Salt Lake City to house the works of the Bureau of Mines in the intermountain area properly has long been projected. It finally became possible when a Public Works Allotment of $300,000 was set aside for building and equipment. With the new building assured, the Bureau of Mines decided to move the headquarters of its Metallurgical Division from Washington, D. C., to Salt Lake City, Utah. It was felt that this move would simplify they administrative work of the chief engineer of the division, as all stations devoted primarily to metallurgical work are west of the Mississippi. These include Rolla, Mo.; Minneapolis, Minn.; Pullman, Wash.; Reno, Nev.; Berkeley, Calif.; Boulder City, Nev.; and Tucson, Ariz. In addition to these stations will groups, of investigators working on metallurgical problem, are maintained at Pittsburgh, Pa., and College Park, Md. Salt Like City was clearly a more central point for the direction of this scattered work than Washington, D. C. The building (fig. 1, A and B) was designed from general plans worked out by the authors of this paper. Contraction was begun in March of 1939, and by the end of the year the Metallurgical Division had moved, into its now quarters.

Jan 1, 1940

Bitumninous and semianthracite coal reserves underlie about 1,400 square miles of Arkansas, less than 2.7 percent of the state's total area. These deposits, located near the western border, contain an estimated 2.2 billion tons, of which about half are recoverable. This represents less than one-tenth of one percent of the national reserves. Most of the commercial coal is mined from thin beds that are at least 14 inches thick. In some locations, however, the coal beds can be as much as eight feet thick. Lignite was mined in southern Arkansas before the Civil War. Current estimates indicate that the reserves may be as high as 9 billion tons, which could be used in the state's coal-fired electric generating plants; however, these deposits are not being mined at present. Because many coal operations in Arkansas are small and the demand for coal is unsteady, the industry employs fewer than 25 miners on a daily basis. Arkansas gained primacy when its regulatory program was conditionally approved November 21,1980, subject to the correction of four minor program deficiencies. The regulatory program was fully approved January 22, 1982. Authority of the state to administer its Abandoned Mine Land Reclamation Program was granted upon approval of the Arkansas Reclamation Plan on May 2, 1983. Arkansas was the first state to assume responsibility for abandoned mine land emergency projects when its Reclamation Plan was approved.

Jan 1, 1992

By Donlad B. Lindsay

This report describes a field-test program to determine the effectiveness of a polymeric wall sealant to reduce the excape of naturally occurring radio-active gas radon from the walls of an underground uranium mine into the ventilation air. A 75-foot-long, dead-end drift with a surface area of about 6,000 ft2 was used as the test site in which the average natural radon flux from the normally dry rock was 16 fCi/cm2-s. The effect on radon emanation of wetting the walls with water to a depth of 3 inches was tested, after which the rock was completely covered with a coating of dry-mix concrete to provide a base for the sealant, an acrylic latex. Sealant was applied in two coats to about 0.25 mm thick. An overall reduction of average radon flux of about 75 pct was achieved. Radon production and other environmental values were measured continuously and automatically by a Bureau of Mines data acquisition system. A commercial microcomputer was programed to convert raw data to engineering units and to perform other useful operations while recording all data on magnetic diskettes. Direct measurements of radon flux from the rock surface were made by a charcoal adsorption technique.

Jan 1, 1981

By E. G. King

An earlier Bureau of Mines report4 provided low-temperature heat-capacity and entropy data for three sodium vanadates. This report continues the study of vanadates by presenting analogous data for three crystalline calcium vanadates - calcium metavanadate (CaV206), calcium pyrovanadate (Ca2V2O7), and calcium orthovanadate (Ca3V208). No similar data for these compounds have been published previously. MATERIALS All three vanadate samples were prepared by the Bureau of Mines by heating stoichiometric mixtures of reagent-grade calcium carbonate and vanadium pentoxide.5 Calcium metavanadate was prepared at 610° to 660° C. A stoichiometric mixture was heated for 17 days with intervening grindings, mixings, and adjustments of composition, as shown necessary by chemical analysis. The final analysis gave calcium oxide, 23.48 pct. (theoretical, 23.57 pct.) and vanadium pentoxide, 76.32 pct. (theoretical, 76.43 pct.). The sample also contained 0.11 pct. acid-insoluble matter. The X-ray diffracton pattern showed no lines of free calcium or vanadium oxides. No X-ray diffraction patterns were found in the literature for any of these substances.

Jan 1, 1961