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By Victor J. Lynch

The Andover-Sulphur Hill mines are 12 miles northeast of Andover and 5 miles southeast of Newton, in Sussex County, N.J. The property is situated on the Lehigh Valley and Hudson River Railroad and half a mile east of U.S. Highway 206. It is connected with the main highway by a hard-surfaced county road. (See fig. 1.) Howard J. Hewitt of Lafayette, N.J., has under lease the Sulphur Hill tract, consisting of 28 acres, and has an option on the Tar Hill tract of 106 acres. The Tar Hill property adjoins the Sulphur Hill on the northeast. (See fig. 2.) The Andover-Sulphur Hill property is owned by the Lenape Corp. of Andover, N.J., while the Tar Hill tract is owned by the Crane Iron Co. of Phillipsburg, N.J. These mines produced iron ore during a period of about 100 years but have not been operated since 1880. Zinc and lead sulfides occur mixed with iron ores in the lower workings of the old mines. A diamond-drilling program was recommended to determine the extent of the sulfide mineralization in depth and also to explore further the iron-ore deposits on the property. The project was started October 6, 1942, and finished November 25, 1942.

Dec 1, 1947

By Benton L. Tibbetts

Comprehensive geophysical measurements were made in the Tertiary Channel gravel deposits of Badger Hill, Calif., with the refraction seismograph, gravimeter, and well logging equipment, to develop a three-dimensional physical model of the gold-bearing gravels. Tests were also made of the applicability of magnetometer and electrical resistivity techniques. Results of 14 seismic profiles revealed four distinct layers with velocities of 1,600 ft/sec for loose gravel, 5,900 ft/sec for compact gravel, 8,600 ft/sec for cemented, blue gravel, and 15,500 ft/sec for bedrock. The depth to bedrock along the middle of the channel varied from a minimum of 100 feet in the hydraulically mined pit area to a maximum of about 300 feet in the upper bench area immediately south of the pit. These geophysical methods revealed that 40 percent of the drill holes necessary to delineate the deposit could be eliminated, at a cost saving of at least 30 percent.

Jan 1, 1971

By B. J. Scheiner

As part of the goal to maximize minerals and metals recovery from primary domestic resources, design factors associated with minimizing current leakage in bipolar cell configurations were studied by the Bureau of Mines as a means of improving the efficiency of bipolar e1ectrooxidation cells. Initial studies that were conducted in a small bipolar cell operating at 140 to 145 volts and 15.4 amp indicated how design factors could be employed to minimize cur-rent leakage around adjacent electrodes during cell operation. Based on these results, a 40-electrode, 108-kva prototype of an industrial-sized cell was constructed and tested for extracting metal values from offgrade molybdenite concentrates. The feasibility of recovering molybdenum and rhenium from the oxidized pulp also was determined. Feed to the process sequence consisted of flotation concentrates containing 16 to 35 pet Mo as molybdenite and 6 to 15 pct Cu. E1ectrooxidation in the prototype cell resulted in 84 to 97 pct Mo and Re extraction with a corresponding energy consumption of 9 to 13 kwhr/1b Mo extracted.

Jan 1, 1979

By Miles B. Royer

The experimental blast furnace has attracted increasing interest during the past decade as a practical means for investigating a broad range of blast-furnace smelting problems. Under experimental-furnace conditions, information can be obtained with less expenditure of time and raw materials and, therefore, at lower cost than comparable information could be obtained under industrial operating conditions. Furthermore, the experimental furnace may be operated beyond the range of smooth operation, even to failure, to delineate the limits of operability. Such deviation from normal operating practice would be economically intolerable in industrial operations where production and operating stability might be disrupted. The Federal Bureau of Mines experimental blast furnace at Bruceton, Pa., near Pittsburgh, has been operated and under development since 1951. However, the usefulness of this experimental data to industrial practice was somewhat nebulous in early experiments, and the correlation of the experimental blast furnace with the industrial blast furnace was not known.

Jan 1, 1961

By W. H. Young, R. L. Anderson

"Physical conditions, such as thickness and character of the coal seam, dip or pitch of the seam, depth of cover, character of roof and overlying strata, mine water, etc., affect the productivity in bituminous-coal mining. Thickness of the coal seam being mined is probably the most important single item that determines whether the output per man per day shall be low or high; however, in strip mining the depth of cover or overburden to be moved is of equal importance.Bituminous coal is mined today from seams of exceedingly variable thickness - less than 2 feet to more than 50 feet; however, a large majority of the mines are producing .coal from seams 3 to 6 feet thick. The average thickness of the coal seams mined in the United States has not changed materially in the past 25 years. The average seam thickness for all bituminous-coal mines was 63 inches in 1920 4/ and 65 inches in 19)45. As thick seams have been exhausted in the older fields, other thick seams, have been opened in the newer fields.Productivity increased from 4 net tons per man per day in 1920 to 5.78 in 1945. This 45 percent increase in productivity resulted from increased mechanization. The percentage of underground production represented by coal cut by machines increased from 61 in 1920 to 91 in 1945 Mechanical loading increased from less than 1 percent of underground production in 1920 to 56 percent in 1945, and strip mining increased from less than 2 percent to 19 percent of the total production during the same period."

Dec 1, 1947

Use controlled blasting techniques to reduce blast-produced overbreak damage to underground mine ribs and back for both safer working conditions and improvements in productivity. The Problem Blasting is used in metal and non-metal underground mine slopes, drifts and crosscuts to fracture rock to be excavated and further processed. Standard blasting also produces fractures in the rock beyond the desired excavation area. This is sometimes evident by rough surfaces, undercutting and other signs of excessive damage. This damage contributes to rockfalls in the mines, a major cause of injuries and fatalities, and equipment damage. A variety of controlled blasting techniques has been developed for civil engineering projects where long-term stability is essential. For several reasons, these methods arc not widely used in mining. For example, these methods incur additional costs and time; there is little need to maintain stable openings over long periods of lime; and there is the perception (hat corrective remedial techniques, such as rock bolting, are more practical. Basically the benefits of these methods are not demonstrably clear for application in underground mines.

Jan 1, 1991

By B. A. Rogers

The problem of obtaining enough manganese for use in the manufacture of steel appears likely to recur when international relationships are disturbed and to become serious at any time when the United States is cut off from its customary supply. Some idea of the problems that an e under war conditions may be obtained from a description given by Ellicott3/ in 1918 before the American Iron and Steel Institute. This condition arises because in normal times there is an economic advantage in importing available high-grade foreign ores to the neglect of our own less satisfactory resources. That considerable low-grade manganese ore and a much smaller amount of high-grade material are available in this country is well known from geological surveys 4/ and has been confirmed by Bureau of Mines investigations. Locations of the various deposits are indicated in figure 1. The possibility of greatly expanding domestic production was actually demonstrated from 1913 to 1918, when the annual production of manganese from domestic ores rose from about 4 percent to approximately 35 percent 6/7/ of the total consumption of ferromanganese and spiegeleisen. In idea of how domestic production compares with total consumption in the United States can be obtained 1 from figure 2, taken from the Minerals Yearbook8/ for 1970. Assuming that it is possible to increase production of manganese ores sufficiently to supply all our needs, such a program presumably would require 2 or 3 years, and the cost of production would certainly rice considerably, for some time at least. For

Jan 1, 1941

By J. B. Zadra, S. M. Shelton, M. M. Fine

"Ferrograde manganese ore or its equivalent is essential to the manufacture of every ton of steel produced; although it is well known that there are large deposits of low-grade ore in the United States, the production of substantial amounts of ferrograde material from domestic sources presents a problem that becomes more and more critical as the stockpiled ore is depleted through inability to procure adequate supplies from foreign sources. Consequently, a program of laboratory and pilot-plant investigation designed to solve the problem of obtaining a domestic supply of manganese has been undertaken by the Metallurgical Division, Bureau of Mines.This paper is one of a new series that will include reports of results obtained in the various investigations conducted under the manganese program. The scope of the program and the organization that woo set up to direct and supervise the work were discussed in the foreword of the first paper of this series, Report of Investigations 3606, Manganese Investigations. 1. Concentration of Manganese Ores from the Drum Mountain District, Utah, by S. R. Zimmerley, J. D. Vincent, and C. R. Schack. Other reports will be published as the work progresses."

Mar 1, 1942

By Hugo E. Camargo

In an effort to reduce Noise Induced Hearing Loss (NIHL) in the mining industry, the National Institute for Occupational Safety and Health (NIOSH) is conducting research to develop noise controls for mining equipment whose operators exceed the Permissible Exposure Level (PEL). The process involves three steps: 1) Noise source identification (NSI), 2) development of noise controls, and 3) evaluation of the developed noise controls. For the first and third steps, microphone phased array measurements are typically conducted and data are processed using the conventional beamforming (CB) algorithm. However, due to the size and complexity of the machines, this task is not straight forward. Furthermore, because of the low frequency range of interest, i.e., 200 Hz to 1000 Hz, results obtained using CB may show poor resolution issues which result in inaccuracy in the noise source location. To overcome this resolution issue, two alternative approaches are explored in this paper, namely the CLEAN-SC algorithm and a variarion of an adaptive beamforming algorithm known as Robust Capon Beamformer (RCB). These algorithms were used along with the CB algorithm to process data collected from a horizontal Vibrating Screen (VS) machine used in coal preparation plants. Results with the array in the overhead position showed that despite the use of a large array, i.e., 3.5-meter diameter, the acoustic maps obtained using CB showed "hot spots" that covered various components, i.e., the screen deck, the side walls, the I-beam, the eccentric mechanisms, and the electric motor. Thus, it was not possible to identify which component was the dominant contributor to the sound radiated by the machine. The acoustic maps obtained using the RCB algorithm showed smaller "hot" spots that in general covered only one or two components. Nevertheless, the most dramatic reduction in "hot" spot size was obtained using the CLEAN-SC algorithm. This algorithm yielded acoustic maps with small and well localized "hot" spots that pinpointed dominant noise sources. However, because the CLEAN-SC algorithm yields small and localized "hot" spots, extra care needs to be used when aligning the acoustic maps with the actual pictures of the machine. In conclusion, use of the RCB and the CLEAN-SC algorithms in the low frequency range of interest helped pinpoint dominant noise sources which otherwise would be very hard to identify.

Jan 1, 2009

By A. J. Kraemer

[During the past several years a great deal of discussion has centered around the question of the permissible limit of sulphur content in fuels for automotive and aviation motors. Under certain conditions of operation, sulphur in motor fuels causes the formation of corrosive substances which attach bearings, wrist pins, and other parts of engines. On the other hand, in making gas¬oline from certain stocks, the gasoline fraction normally contains a relatively large proportion of sulphur compounds. By the generally used processes of reducing the sulphur content, a significant part of the gasoline fraction is lost as motor fuel, and added expenses are entailed for chemicals, labor, and other process costs. This condition has been an economic burden to some refiners of high-sulphur crudes. In some instances the treating losses have been rather severe and the treating costs relatively high, but the data presented in this paper indicate that the reduction of sulphur content of motor fuel is a problem to a relatively small number of refiners and of little or no concern to the remainder; in fact, more then 90 per cent of the 153 samples analyzed passed the Federal specification requirement, which limits the sulphur content to 0.10 -nor cent. 3 This report is based upon the results of an examination for sulphur content, Doctor test, copper strip corrosion, and color of the samples collected during January, 1930, for the twenty-first semiannual gasoline survey of the Bureau of Mines. The results of the gravity and distillation tests of the survey were published as Report of Investigations 2995. The numbering of the samples given in this report is the same' as in Report of Investigations 2995; for example, No. 25 of this report is the same sample as No. 25 of Report of Investigations 2995.]

Jan 1, 1930

By Clinton C. Knox

During the latter part of 1943, a magnetometric survey was conducted by the Geophysical Division of the Bureau of Mines at the Mahopac magnetite mine, Putnam County, N. Y., in an endeavor to locate a segment of the ore body that reports state was cut off by a fault. The Mahopac mine was abandoned about 1895 after producing nearly 1,000,000 tons of high-grade magnetite iron ore. The results of the investigation indicate the termination of the ore body by "pinching", or a displacement of such magnitude as to place any extension at a considerable distance from the original are body. This report describes the work done on the project and presents the data obtained.

Jan 1, 1948

By T. M. Barczak

Many of the support concepts currently used in the United States originated in South Africa. These products include the Hercules Crib1, Propsetter, MX Prop, Rocprop, and Spider Prop. Another recent development has been the introduction of hydraulic prestressing units, such as the Jackpot system, to various U.S. standing support systems. Several other prop-type supports with similarities to systems used in South Africa are in use in U.S. coal mines. Some exciting new developments that improve the installation and yield performance of props are also underway. In addition to prop-type supports, crib-type supports and single-unit systems such as the Can support are also frequently utilized in longwall tailgates in the U.S. The goal in U.S. support development is to enhance roof support capability while alleviating material handling barriers to reduce injuries associated with support handling and installation. Support products are generally full-scale tested at the National Institute for Occupational Safety and Health (NIOSH) in the unique Mine Roof Simulator load frame. The performance testing protocol is designed to simulate the full range of load conditions that occur in underground mining to identify the performance deficiencies and limitations of the support products. Once the products complete the performance evaluation, they are implemented into the NIOSH Support Technology Optimization Program (STOP). STOP is a window’s based software program that was developed by NIOSH for facilitating the design of standing roof support systems. STOP has become an industry standard to compare the performance capabilities and facilitate the application of these support products into various mining conditions. The purpose of this paper is to provide an overview of the support design and application philosophy in the United States.

By J. E. Tress

The Bureau of Mines has developed a process to utilize waste heat from electric arc steelmaking furnace gases to preheat the ferrous material charged to the furnace. Four heat exchangers were designed, tested, and operated successfully on 1-ton electric arc furnaces. Briquets and pellets were charged continuously, both countercurrent to the hot furnace offgasses and at ambient temperatures. A comparison of the electrical energy consumed in each situation showed that preheating can lower energy requirements as much as 15.6 percent.

Jan 1, 1975

Lower workers' dust exposures during bag stacking while ergonomically improving the bag stacking process. Approach Install a new pallet loading dust control system which uses a push-pull ventilation technique along with a hydraulic lift table to control the pallet loading height throughout the entire loading cycle. How It Works A low-volume, high-velocity blower system operating at approximately at 120 cfm blows a stream of air over the top layer of bags on the pallet. The blower system is composed of two 3-inch air jets (approximately 1,200-ft/min velocity) directed toward an exhaust system on the opposite side of the pallet. As these air jets travel across the pallet, they en-train dust generated during bag stacking. The dust laden air is then captured by the exhaust ventilation system which draws approximately 2,500 cfm through an exhaust hood on the opposite side of the pallet.

Jan 1, 1989

By E. S. Shedd

The Bureau of Mines investigated electrowinning and tapping lanthanum metal from lanthanum oxide in a fluoride bath. The electrolyte was composed of LaF3, BaF2, and LiF. Metal containing 0.2 percent impurities was produced at a rate of over 2 pounds per hour. Principal impurities were carbon, aluminum, and silicon. Low-carbon metal was produced by continually discharging the carbon oxide gases and maintaining 0.1-atmosphere pressure. Anode reactions and cell design were found to be important factors in cell operation. Both frozen electrolyte skulls and tungsten metal crucibles proved satisfactory for collecting the metal and did not react with the molten lanthanum.

Jan 1, 1966

By K. K. Kelley, L. B. Pankratz, W. W. Weller

The heat capacity of columbium (niobium) carbide (CbC ) was measured over the temperature range from 51 ° to 298 ° K, and the entropy at 298.15° K was evaluated . Also , the heat content above 298.15 ° K of columbium carbide was measured to 1,800 ° K. The results were combined with the known heat of formation at 298.15 ° K to obtain values of the heat and free energy of formation over the temperature range from 298.15 ° K to 2,000 ° K.

Jan 1, 1964

By J. R. Ruark

This report presents results of mining operations and of research and development work done during stage I of the gas combustion retorting research program conducted by the Colorado School of Mines Research Foundation and six major oil companies at the Bureau of Mines Anvil Points Oil Shale Facilities. A brief description of the gas combustion process is given and the experimental program is discussed. Included in this discussion are (1) air-gas distributor development, (2) results of gas and shale distribution studies, and (3) effects of other process variable studies. The report concludes with a statistical evaluation of experimental results. Two appendixes present a chronological account of the experimental work and tabulations of data for all retorting runs conducted during stage I.

Jan 1, 1969

By R. E. Head

"The microscopic work described below was engaged in primarily into ascertain the approximate proportions in which the copper sulphides existed in the ore examined, and by a comparison of the results obtained from a study of both head are tailing samples to supply data which might be of value in treating the ore by flotation. Incidentally, the physical characteristics and association of the sulphides were noted in order to determine the possible relation or bearing of these features on the present conditions of treatment. Since the copper in the ore occurred as three distinct sulphide minerals - chalcopyrite, chalcocite, and bornite each containing copper in different proportions, there appeared to be little or no possibility of obtaining the desired information by chemical methods of determination.Type of material examinedThe material examined was in the crushed condition and was said to be representative of the flotation feed or heads and the resulting tailing. No hand samples of the ore were examined nor any account taken of the physical condition and association of the minerals in place, because the possible value of the analytical results depended on conditions as they existed in the crushed ore. As the problems under consideration dealt only with the sulphide minerals, especially those of copper, the products from screen sizing were concentrated by hand panning and the gangue discarded. The concentrate obtained consisted almost entirely of the sulphide minerals, since the panning had been very carefully done. The object of this procedure was to obtain a sufficient quantity of high-grade sulphide material, from the sample of each screen size selected for examination, to permit its being so prepared for examination as to be representative of the physical characteristics exhibited by a large number of sulphide grains from each respective size, In the tests and investigations carried on by the company' treating the ore the following sizes had been used in tabulating data and basing conclusions:+48, +65, +100, +150, +200, and -200. These same sizes were used in the microscopic investigation, since the results obtained thereby could be most readily utilized for comparison with the results obtained in previous experimental work, together with deductions based on actual concentration of the ore on a commercial scale."

Jun 1, 1921

By James E. Bell

Quartz crystals occur on a farm in the vicinity of Laurel Fork, Carroll County, Va., in abundance over a large area, This has been known for several years, but no work had been clone, up to the Bureau of Mines examination in 1943, to determine the amount of crystalline quartz of usable quality. Field exploration was undertaken throughout the month of June 1943.

Jan 1, 1950

By James V. Kelly

During the spring and summer of 1947, the Bureau of Mines conducted an investigation and core-drilling program in the vicinity of the Rodham mine, approximately 4 miles north of Shullsburg, Wis. This work was undertaken as a part of a general study of the zinc and lead-producing area of southwestern Wisconsin. Work in the Rodham-mine area was done to investigate further a mineralized area frilled in part by the Puritan Exploration Co., a Delaware corporation, with offices in Galena, Ill. Some significant lead-bearing samples were obtained, but no continuous ore body was disclosed as a result of the Bureau of Mines work.

Jan 1, 1949