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By Benjamin W. Haynes

The Bureau of Mines conducted research to provide technical information needed to devise waste management plans for the processing of manganese nodules. Studies included summary descriptions of Pacific manganese nodules, process options and flowsheets, methods for characterizing nodules and their tailings, and results of analyses of laboratory and pilot-plant generated tailings. This information is the result of a cooperative research effort of the Bureau of Mines and the National Oceanic and Atmospheric Administration (NOAA), with NOAA providing funding and the Bureau conducting the research. A summary of the extensive literature review is provided for manganese nodule mineralogy, chemistry, processing techniques, and methods of analyses. Characterizations and analyses of laboratory-generated tailings and slags are given, as well as the results of the leaching studies on these waste materials. Leachability was determined by three standard leachate tests- the Environmental Protection Agency (EPA) extraction procedure (EP) toxicity test, the American Society for Testing and Materials shake extraction test, and the U.S. Army Corps of Engineers-EPA seawater elutriant test. While the wastes generated in the laboratory may not be entirely representative of those to be generated in full-scale plants, results of these studies provide a positive indication that commercial recovery of cobalt, copper, manganese, and nickel from manganese nodules would be environmentally acceptable.

Jan 1, 1985

By Clifford B. Farris

The natural cementation strength of retorted oil shale is the focus of this investigation. The optimum retorting temperature and residence time to obtain natural cementation strength in retorted Green River oil shale from western Colorado were determined as follows: [Optimum Conditions for Natural Cementation Maximum Residence Obtained Retorting Time at Compressive Mode of Temperature Temperature Strength' Retorting °F °C hr psikg/cm-2 Direct 1,520 822 2.0 270 19.0 Indirect 1,530 832 2.9 325 22.8] 1 Scattered samples were tested at strengths as high as 463 psi (32.6 k /cm 2) (Run 8, indirect mode) and 406 psi (28.5 kg/cm2) (Run 48, direct mode), but these high strengths were not confirmed by nearby tests. Minus 0.5-inch (1.3-cm) Green River oil shale was heated in a differential retort under conditions simulating potential full-scale retorting processes. The variables investigated were retorting temperature, residence time, retorting mode, and shale grade. Samples of the retorted Green River oil shale were moistened to optimum plus 2% (25%) moisture, compacted to 95% Proctor density, sealed and cured at 100°F (38° C) for up to 40 days. Lower curing temperatures, which are likely in the field, would probably result in significantly slower development of cementation strength, and might lower the ultimate strength developed. However, these effects were not studied in this project. The cured samples were tested for compressive strength, and correlative equations were developed for the increase of compressive strength with curing time as a function of retorting temperatures and residence time. Petrographic analysis indicated that the cementing mechanisms may be the interlocking growth of acicular hydrated calcium aluminum sulfate crystals between the contacts of retorted shale fragments. Samples of the retorted shale were also tested for optimum Proctor density and moisture. Permeability and quality of the leachate of shale from typical runs were determined. The effect of use of retort rather than tap water on compressive strength and leachate after curing was determined. The retorted shale effectively filtered several mineral constituents from the retort water.

Jan 1, 1979

By F. W. Brown

In 1942 the Explosives Division investigated electrostatic hazards associated with the manufacture, storage, and use of explosives. A report was issued in 19454/ presenting the data on the spark sensitivities of explosives. In 1948, the apparatus was redesigned and rebuilt to make the routine testing of explosives safer and more convenient. The rebuilt apparatus is described in this re-issue of the former report. Included are details of construction and a list of parts. PRINCIPLES OF METHOD In normal procedures without special precautions, it is possible for static charges to be accumulated on individuals or on ungrounded equipment or structures.5/ Static charges may be produced in many ways, but they are most commonly produced by rubbing or successive contact and separation of unlike surfaces, at least one of which is usually an insulator.

Jan 1, 1953

By A. E. Petersen

To reduce U.S. dependence on imports of titanium, the U.S. Bureau of Mines has investigated the recovery of titanium from perovskite (CaTi03). Domestic perovskite deposits represent a significant, but untapped, titanium resource. An acid sulfation method was developed that will extract about 97 pct of the titanium and the columbium and 70 to 90 pct of the rare-earth byproducts from perovskite concentrates. A flow-sheet for recovering titanium as pigment-grade titanium dioxide (Ti02) is discussed. Test work performed in developing each unit operation is described. The first three unit operations have been demonstrated using laboratory-scale continuous methods of operation: acid sulfation of perovskite concentrates, leaching sulfation residue to dissolve metal values, and precipitation of titanium oxysulfate monohydrate (TiOS04?HP) from the resulting leach flltrate. Batch testing of other unit operations was performed: TiOS04?H20 redissolution and iron reduction, precipitation of Ti02 by hydrolysis, and regenerating recoverable acid with rare-earth byproduct recovery. Cost evaluation results are provided, indicating that processing perovskite concentrates by acid sulfation may be an economically viable means of producing Ti02.

Jan 1, 2010

By E. A. Magill

The Bureau of Mines has begun a study of the copper resources of the Cascade Mountains of Washington. The program includes reconnaissance of mineralized areas and examination and occasionally limited exploration of deposits that are considered characteristic of an area. The Bureau of Mines believes that published information may assist industry in searching for new sources of copper. The Miners Queen is one of a few Cascade Mountain deposits selected for prelim¬inary exploration. The investigation was not planned to delineate the ore body. A diamond-drilling program was carried out at the Miners Queen mine in the summer of 1955. Five diamond-drill holes were completed, totaling 628 feet. Two 35-foot shafts were dewatered, and all accessible underground and surface workings were examined.

Jan 1, 1957

By T. T. Read, T. L. Joseph, F. H. Royster

In a preliminary study of the beneficiation of iron ores conducted by the Bureau of Mines, one of the authors (T. T. Read) found it necessary to ascertain, if possible, how much effect a decrease in the silica content of an iron ore has upon the cost of making pig iron from the ore. In the beneficiation of iron ores the most important impurity to be removed is usually silica, and the amount that can be expended on a beneficiation process to reduce the silica content of the ore is obviously determined by the amount of increase in the value of the ore after beneficiation. The price that can actually be obtained for a beneficiated ore is, of course, a matter of negotiation between the seller and the buyer, but since the relative value of different grades of iron ore must be chiefly based upon the cost of making pig iron from them, an approximation as to the effect which decrease in the silica content of ore has upon the cost of snaking pig iron is an important guide in estimating what probable average gain will result from subjecting an ore to a beneficiation process. A search of the literature failed to reveal any detailed statement on this important topic, but fortunately the data are at hand to permit making an approximate calculation of the probable effect. For the purpose of the calculation assume three iron ores with the following composition (natural):

Jan 1, 1924

By W. Reed

During the 20th century, the increased emphasis on worker health and safety and the advent of new mining equipment and methods led to many changes in mine face ventilation practices. Efforts by government and private industry to improve and modify ventilation practices resulted in better health and safety conditions for workers. This paper examines factors that had a significant influence on mine face ventilation design during the past century. Several “milestone” events are discussed along with the impact they had on worker health and safety. Significant ventilation research efforts by government and private industry are presented. This brief ventilation history highlights innovative ventilation designs and a consistent commitment to mining health and safety.

By Oliver Bowles

"Rhodesian asbestos is of high quality and is much in demand by American consumers. Production in Rhodesia was first reported in 1909. The production for this and each succeeding year is shown in the following table:The serious curtailment in production for the years 1912 and 1913 was occasioned by transportation difficulties. In 1914 a railway was projected to Victoria and thereafter production increased greatly. Up to 1916 asbestos was obtained,from the Victoria district only, but thereafter the Bulwayo district became an important,producer with minor quantities from Gwelo.In the Bulawayo district the productive area is about 2 1/2 miles long, with Shebanie mine at the north-west end, the Nil Desperandum at the south end, and the Birthday claims between them."

Oct 1, 1920

By C. M. Harrer

This paper describes the location and general features of iron occurrences in Colorado. Most of the deposits were examined; many are in forested and mountainous areas at altitudes of 5,000 to 13,700 feet. Iron is known to occur in 30 counties of western Colorado. Transporting the ore to market is a handicapping economic factor involving long truck and railroad hauls; the nearest purchaser of smelting ores is the Colorado Fuel and Iron Corp., at Pueblo, Colo. When the ore can be sold locally for special purposes and at higher prices than can be obtained at iron smelters, small-scale operations can supply that market.

Jan 1, 1959

The U.S. Bureau of Mines, Department of Labor, and United States National Committee of the CIE hosted the TC4.10 Mine Lighting Committee Meeting and Second International CIE Mine Lighting conference at the MSHA Academy in Beckley, WV from October 12-16, 1981. This was the first time the meeting and conference had been held in the United States. The TC4.10 Mine Lighting Committee, chaired by Dr. Adam Peretiatkowicz of Poland, was attended by 15 committee members and six guests representing eight countries. Discussion during the meeting covered mine lighting instrumentation, open cast (surface mine) lighting, and lighting sources. The committee also reviewed a draft of proposed lighting terminology and suggested changes to make the definitions more acceptable to representatives of the nations present. The mine-lighting conference featured 20 papers presented by 18 speakers representing six countries. The papers covered all phases of mine lighting, including research, hardware development and application, personnel acceptance, and requirements for system maintenance. The conference attracted 126 attendees and also included displays by eight lighting hardware manufacturers and four mining machine manufacturers. Papers from the conference are being published by the Government Printing office, with copies presented to the conference attendees. Copies will be available to others interested through the NTIS. During the course of the TC4.10 meetings and conference, committee members toured three mining equipment assembly plants, and six of the foreign representatives visited a longwall installation in an underground mine. Planning and administrative services for the meeting and conference were handled by Bituminous Coal Research, Inc., under USBM Contract H0318038.

Jan 1, 1982

By A. Aly Selim

This report describes the feasibility of predicting percussive drilling rates by equations derived from statistical regression analysis. The least squares statistical method was used and the analysis was performed both by direct and by stepwise linear regression analysis. The predicted penetration rate is a function of the drill power and the physical properties of the rocks penetrated. The results show promise that the technique may be of value in providing a mathematical model by which percussive drill manufacturers and users can predict the performance of a given drill. Experimental work involved two mining type percussive drills. Penetration data for these drills were determined from nine rocks drilled in the laboratory. Drill work rates (power) were determined in a separate series of experiments. Rock physical properties were measured from diamond-drill core samples taken from the same blocks used for percussive drilling.

Jan 1, 1970

By C. E. Arrington, A. C. Rice

"Part 1. REDUCTION AND USE OF OXIDANTSSUMMARYA study has been made of the volumetric determination of molybdenum by reduction in the Jones reductor, receiving the reduced solution in a mixture of ferric alum and phosphoric acid, and titrating with standard oxidizing agents. In addition to potassium permanganate, which has long been utilized for this titration, potassium dichromate and ceric sulphate have been found to be applicable. The latter oxidants have been found to be especially useful in the form of dilute solutions for the determination of small amounts of molybdenum. The tests revealed that certain internal indicators give excellent results in these titrations.Reason for These ExperimentsThe following study was initiated with the hope of providing the mining and metallurgical industries with an accurate and rapid technical method for the determination of molybdenum in such low-grade materials as ores, rocks, tailings, steels, and alloys containing less than 0.3 percent molybdenum. Although the experimental work was designed with this purpose in mind, many of the results are applicable to material containing a higher percentage of molybdenum.While the Bureau of Mines had an experiment station in Colorado, considerable analytical work was done on what were then (up to about 1923) classed as rare metals. One of these was molybdenum; and in Bulletin 212, Bonardi's (1) 3/ 60-page chapter covered all methods for the analysis of molybdenum."

Apr 1, 1939

By Fredrick L. Johnson

Tungsten is the principal mineral commodity in the Laurel-McGee RARE II area; copper and molybdenum would be recovered as by-products with the tungsten. Indicated and inferred tungsten marginal reserves at the Hard Point Mine (fig. l, no. 10) are 16,000 tons (14,000 t) averaging 1.0 percent tungsten trioxide (W03). The mine is outside the RARE II area, but the geologic structure that it is on extends into the area. Indicated subeconomic zinc, silver, copper, and lead resources at the Lucky Strike Prospect (fig. 1, no. 7) are nearly 6,200 tons (5,600 t) averaging 5.45 percent zinc, 0.5 oz silver per ton (19 g/t), 0.40 percent copper, and 0.32 percent lead. Although tungsten has been produced at the Tiptop Mine (fig. 1, no. 12), resources were not calculated because of the spotty nature of the tungsten mineralization. Additional exploration at the Tiptop and Hard Point Mines could reveal significant resources. The potential for tungsten resources at the Payday Prospect, Tungsten Prospect, and Morhardt Mine is also high. The Pine Creek Mine custom mill, located about 35 mi (56 km) southeast, could process tungsten concentrates from the area. Tungsten production has been recorded from three properties, the Hard Point, Morhardt, ant Tiptop Mines. Output was about 405,000 lb (184,000 kg) of W03, nearly all from the Hard Point.

Jan 1, 1983

In this U.S. Bureau of Mines report, two drill-split mechanical excavation mining system concepts are described, casted, and cost compared with conventional drill-blast mining systems. The concepts for the two drill-split mechanical excavation mining systems presented are (1) a method for steeply dipping narrow veins 0.6 to 1.2 m wide and (2) a longwall method for fiat-lying tabular ores. In the proposed systems, 70 to 80 pet of the ore is disposed of underground as backfill. For sortable ores, face area crushing, sorting, and direct stowage of run-of-mine waste and low-grade ores are proposed. The underground sorting and stowing of waste reduce materials handling, processing, and waste disposal costs by reducing the quality of ore transported to the surface by 70 to 80 pet (by volume). Because many of the tools and techniques proposed for use in these systems have little or no historical mining industry use, cost assignations are heavily influenced by engineering judgments and presented as prefeasibility-level cost estimates. These estimates, presented as discounted-cash-flow-rate-of-return (DCFROR) values, show the proposed systems to be at least as profitable as, and in some cases 50 pet more profitable than, conventional drill-blast mining.

Jan 1, 1994

By Eugene H. Skinner

The 7-mile Flathead Tunnel, located in the central Salish Mountains of northwestern Montana, was constructed between 1966 and 1969, With the contract awarded April 19, 1966, drill and blast tunnel excavation began September 30, 1966, and was completed June 21, 1968, in 488 tunnel-driving days, Peak advance was 66 feet per day. On June 27, 1969, all tunnel concrete lining was completed. Average wall and arch concrete placing rates exceeded 1,700 cubic yards daily, with nearly half of the concrete placed during a severe winter season. Major cost savings in concrete tunnel lining were achieved through a value engineering clause in the contract. Achieving consistent results and high rates of placement in concrete lining ranked equal to ground control in overall tunnel problems. Ground control problems exceeded expectations and were of continual concern throughout excavation, One support collapse in the tunnel and one portal slide condition developed during construction. Critical surface geologic exposures were largely obscured; only a portion could be accurately projected underground, An instrumentation program to gather basic data on rock defamation near the heading face for support purposes was a pioneering effort. The Flathead Tunnel was placed in service on November 7, 1970.

Jan 1, 1974

By William O. Vanderburg

This paper gives the results of a reconnaissance of the mining districts of Mineral County, Nev., made during the month of June and the first 10 days in October 1936.3/ During the field work virtually all the mining districts in the county were visited and many data were obtained relative to active and inactive properties. The report covers the location of the various mining districts, nature of deposits, ownership, information on past and current activity, data on economic conditions, and general information likely to be useful to operators and investors and others interested in mining. The geology of the deposits is discussed only in a general way. For nearly three-quarters of a century mining tin Mineral County has been the principal if not the only industry of importance. At times it has reached a very low ebb, and at other times it has been attended by the wild excitement that usually accompanies valuable discoveries of precious metals.

Jan 1, 1937

By Joan C. Biordi

A molecular beam-mass spectrometer-low pressure flat flame apparatus has been constructed for the purpose of examining the chemical microstructure of normal methane-oxygen-argon flames and those inhibited with Halon extinguishants. Details of construction and performance of this apparatus and of related flame temperature measurements are given. Particular attention is paid to the empirical characterization of the perturbation to the flame caused by the sampling probes. The composition profiles obtained for normal flames are compared to those of flames inhibited by CF3Br. In addition to the usual stable species (CH4, O2, CO, CO2, H2O, H2, and H2CO), the inhibitor, its products and intermediates associated with its reactions could be followed. In particular, hydrogen bromide, bromine atoms, hydrogen fluoride, and carbonyl fluoride were observed. The relatively rapid disappearance of inhibitor and early appearance of fluorinated reaction products suggest a short lifetime for the CF3 radical in this system. Observation of COF2 suggests that CF3Br is effective as an inhibitor, at least in part, by virtue of its interference with the oxygen containing species of the normal chain reaction. Profiles of the 17+ peak at low electron energy suggests that the hydroxyl radical may also be sampled, but the profiles obtained are not yet sufficiently accurate to determine the effect of inhibitor on this important flame radical.

Jan 1, 1973

By R. L. Marovelli

ANTICIPATING the eventual use of the huge tonnages of nonmagnetic taconites of the Mesabi range of the United States, the Federal Bureau of Mines is classifying and evaluating these deposits in detail. This introductory report describes work begun in 1954 as part of a long-range program to sample, classify, and evaluate important occurrences of nonmagnetic taconite on the Mesabi, range. Included in this report are brief discussions of the geology, history, and potential of the Mesabi range district and mining industry, together with a more detailed presentation of the sampling and metallurgical evaluation of these nonmagnetic taconite deposits. A total of 898 field samples was collected. Most of these were taken in the region between Grand Rapids and Chisholm, Minn., but a few came from the area between Chisholm and Buhl, Minn. Of the total samples, 865 were from open pit bank faces where the greater vertical distances presented by the cherty members facilitated the taking of a large number of samples. Conversely, the narrow face presented by the slaty members confined and limited the areas from which samples were taken. In addition, 33 of the field samples were taken from rock dumps in order to determine, in a preliminary way, the characteristics of these materials.

Jan 1, 1961

By R. Blickensderfer

The laboratory wear testing capabilities of the Bureau of Mines are described, Wear tests are used to support the Bureau?s research efforts toward reducing the wear of equipment used for mining and minerals processing and any wear involving a loss of strategic or critical materials. The emphasis is on abrasive wear because it accounts for most of the wear losses that occur in mining and minerals processing equipment, Spalling wear, caused by repetitive impact in grinding equipment, also is included, Ten abrasive wear tests, including high- stress and low-stress and two-body and three-body conditions, are described: dry-sand, rubber-wheel abrasive wear; Taber Abraser; abrasion resistance of refractory materials; dry-particle erosive wear; elevated-temperature, dry-particle erosive wear; low-angle slurry pot; jaw crusher gouging wear; ball mill wear; pin-on-drum abrasive wear; and high-speed impact gouging. Two repetitive impact tests are described: ball-on-block impact-spalling and ball-on-ball impact-spalling. Test equipment, procedures, and specimens are described, and typical test results are presented and discussed.

Jan 1, 1985

By R. G. Knickerbocker, T. E. Evans, D. R. Torgeson

"INTRODUCTION Sponge iron is a product resulting from the reduction of an iron oxide at such a low temperature that fusion does not occur, and the reduced particles retain substantially the same shape as the original ore. The removal of oxygen in the reduction process leaves the metal porous and reactive. Sponge iron may be compared in general to a chemically precipitated substance insofar as reactive properties are concerned. The high specific surface and the orientation of metallic structure are factors which probably contribute to the reactive properties of sponge iron.The term ""gaseous reduction,"" as applied to iron ores, required clarification. Strong evidence exists, for example, that ore is partly reduced to sponge iron by carbon monoxide in the blast furnace at temperatures around 800° C. at a point that may be as high as 30 feet above the tuyores. In 1923 and 1924, Sims and Wood attempted to reduce iron oxide with carbon in an Arsem vacuum furnace at 980° C. These investigators found that only 6 percent of the iron was reduced to metal when the iron oxide-carbon mixture was heated for 1 hour under evacuated conditions, whereas at atmospheric pressure 70 percent of the iron was metallized. Their results indicate that the process of iron-ore reduction at temperatures below the melting point of the ore may proceed largely, if not entirely, by the action of reducing gases even when the reducing agent is solid carbon. Therefore, the term ""gaseous reduction,"" as used heroin, is defined as a process in which iron ore is brought into intimate contact with a reducing gas produced in separate-equipment from the reduction chamber itself.A large amount of pilot-plant development on gaseous reduction of iron ores has been carried out by the Bureau of Mines at the Boulder Experiment Station and had as its objective the reduction of fine iron ore by means of producer gas. The use of use gas was prompted by two considerations: First, the possible utilization of large reserves of Western noncoking bituminous coals and lignites contiguous to iron-ore drewwing; and second, an investigation of the results that might be achieved in the pilot-plant gaseous reduction of fine iron ores by means of a relatively reducing gas. The results obtained, it was felt, would be of considerable value in indicating the direction which gaseous reduction experimentation must take for the development of a commercially practicable and economic process for the production of sponge iron."

Dec 1, 1946