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By Raymond O. Dannenberg

The Bureau of Mines conducted laboratory and full-scale tests to develop a process for improving the flotation characteristics of lime-treated waste water produced by the Kennecott Copper Corp., Magna, UT. Unknown substances in the waste water reduced the flotation efficiency of the metal sulfides. An estimated annual loss of 795,000 lb Cu, 232,000 lb Mo, 5,625 tr oz Ag, and 617 tr oz Au would result from recycling the total flow from the lime treatment plant to the flotation mill in an effort to conserve water and reduce associated expense. The tests indicated that aeration or treatment with activated carbon significantly improved the water quality. The improvements in molybdenum recovery averaged 8 pct for carbon, 11 pet for activated carbon, and 16 pct for combined aeration and activated carbon. The combination of the two processes produced water quality as good as or better than normal feed water.

Jan 1, 2011

By W. G. Sandell, L. C. Bauerle, K. C. Dean

"INTRODUCTION As a part of the wartime activities of the Bureau of Mines, metallurgical services were extended to other Government agncies engaged in purchasing and stock-piling some of the more critical and strategic materials. At the request of Dr. Alan M. Bateman, special representative of the Metals Reserve Company, metallurgical studies were made on three samples of oxide tin ore from, the States of Zacatecas and Guanajuato, Mexico. The samples were submitted for testing by A. Porraz of the Financiera Miners, S. A., institution Financiera, Edificio Guardiola, Despachos 500-507, Mexico, D. F.The samples as received were marked Nos. 1, 2, and 3 and described as follows:Sample 1. - Origin: Mining camp ""El Naranjo,"" municipality of Sombrerete, State of Zacatecas, Mexico. This sample was partly concentrated by washing and as received was all minus 10-mesh in size.Sample 2. - Origin: Deposits in Sierra. Fria and Juan Cherey, municipality, of Jerez,State of Zacatecas, Mexico. This sample represented run of-mine ore.Sample 3. - Origin: Mine ""La Frontere, "" Ranch of San Pedro del loya, State of Guanajuato, Mexico. This run-of-mine sample was low in tin content but came from a highly mineralized tin field."

Jun 1, 1947

By Alphonso Cornejo, Galen H. Clevenger

This bibliography was compiled in connection with an investigation of the Caron process for the treatment of manganese - silver ores , conducted by the T. S. Bureau of Mines in cooperation with the Netherlands East Indies Government . The object of this investigation was to develop a practicable method for treating the refractory manganese- silver ores found in these two countries . The results of the work will be published as a bulletin of the Bureau of Mines . This bibliography summarizes the available information on the subject previous to the investigative work embodied in the forthcoming bulletin, and may be useful to those metallurgists or others conducting work along this line .

Mar 1, 1923

By Steve Bessinger, Steve Signer, James Pile

The San Juan Mine and the National Institute for Occupational Safety and Health conducted a study to measure how development mining affected bolt loads. Twelve fully grouted, instrumented roof bolts were installed at two three-way intersections as part of the standard bolting pattern. Newly developed miniature data acquisition systems (MIDAS) were used to measure bolt load changes during initial face advance and cross-cut breakthrough. The effects of cut placement and depth on roof bolt loads were studied. This test showed how bolt loads increased at five positions along the bolt length during initial mining. Both entry advance and cross-cut breakthrough produced a similar percentage of increase in bolt loads. Geologic differences between the test sites were probably responsible for the differences in amounts of bolt loading. The test site with more top coal and a higher rock quality designation (RQD) had lower bolt loads.

The object of this program was to extend the capabilities of visual paging systems both in size and function. The system developed uses the mine pager phone line for communication, monitoring, and remote control. A central station, using a minicomputer, transmits signals by phase inversion modulation of a 16,384 Hz carrier to as many as 999 remote units. The remote unit addressed returns An echo to indicate that it is functioning and, in the case of monitor units, to convey the monitor data. Magnetically latched display dis[c]s, which can be seen from both sides when posted, are used for visual paging. Lists of the addresses of posted pages, unanswered pages, and non-echoing units are prepared by the central station computer. The system was designed to be intrinsically safe and should operate for three months on a 12-volt lantern battery.

Jan 1, 1980

By John R. McWilliams

This report is one of a series published by the Bureau of Mines describing methods and practices at various mines throughout the United States. A previous program, conducted from 1928 to 1939, was well received by the mining industry and technical institutions and provided much source material for engineering textbooks and technical handbooks. The stringent wartime demands on the mining industry, the rapidly changing postwar economic situation, and greatly accelerated technologic growth have combined to render many of the previous data obsolete. The objective of the present program is to assemble reliable technical information on mining methods and practices throughout the country and present it for the use of the mining industry, technical schools, textbook authors, and other interested persons. This report deals with the design and development of the Berkeley open- pit mine at Butte, Mont., owned and operated by The Anaconda Company. The Berkeley pit is but one facet of a well-organized and integrated copper-mining operation involving the entire Butte district. Vein-type mining, important for 75 years, is still in progress at depths from 600 feet to nearly 1 mile; on intermediate levels, low-grade ore left untouched by earlier vein-type mines is being extracted by block caving entire ore zones,3/ and secondarily enriched but lower grade near-surface portions of the same ore zones are being mined by open-pit operations (fig. 1). The Berkeley pit itself is named for the Berkeley mine, one of the old mines that extracted copper ore from high-grade veins in the area that now will be mined by open-pit methods.

Jan 1, 1959

By R. S. Fowkes

The Bureau of Mines constructed a fully automated pilot plant facility to study the hydraulic transportation of solids through a lock hopper feeder system. An equation for the energy requirements to transport coarse solids hydraulically proved applicable to this system. Optimum velocities were obtained for limestone, mine refuse, and bituminous coal. The experimental data, calculations, and graphs show the effect of velocity, specific gravity, and solids concentration on head loss and power requirements. Other data were obtained and evaluated to determine the effect of particle size on head loss. Results also are given for (a) tests using friction reducing polymers; (b) tests using seven test sections of steel alloy pipe to determine their wear characteristics; (c) tests to determine spatial segregation of moving particles; and (d) tests to determine the effect of shape, size, and specific gravity on particle velocity in a horizontal pipeline. The lock hopper feeder system was found practical for continuous hydraulic transportation of the material types and size ranges tested.

Jan 1, 1969

Horizontal holes are drilled underground into coalbeds to control methane flow from ribs and active face areas and to make gas pressure measurements in coalbeds. Gas pressure measurements are made by drilling the same hole incrementally. After each increment, the hole is filled with some type of packers and allowed to reach equilibrium before a gas pressure reading is taken. As the length of hole increases, more packers are required to effect a seal and obtain a reliable pressure measurement. Problems have been encountered in obtaining satisfactory packer seals due to the friable nature of the coalbed. New methods of packing the holes must be used. Therefore, this project was established to evaluate materials and develop a new technique in which a semiliquid and/ or rigid type grout could be placed in the hole to provide satisfactory sealing.

Jan 1, 1972

By Alla D. Mah

The energies of combustion of zirconium carbide and hafnium carbide were measured by combustion calorimetry and the heats of combustion and formation. of zirconium carbide and hafnium carbide were derived . The results are-- ZrC AH298.15 ( combustion) = -308.60 ± 0.55 kcal /mole , AH298.15 ( formation) -47.0 ± 0.6 kcal /mole , AH298.15 = HfC (combustion ) = -306.08 ± 0.20 kcal/mole , AH298.15 ( formation) -52.3 ± 0.4 kcal /mole . = INTRODUCTION This report contains the results of calorimetric measurements to obtain the heats of formation of zirconium carbide ( ZrC) and hafnium carbide ( HfC) . The work was conducted as part of a Bureau of Mines program for determining the heats of formation of oxides , carbides , and nitrides by combustion calorimetry . Combustion calorimetry is one of the most precise calorimetric techniques . The chief obstacle to obtaining accurate heat of formation values for carbides , and the chief reason for the variation in the results of different investigators , is the lack of purity of the carbide samples . Corrections for impurities always involve assumptions which lead to uncertainties . In general , a large impurity correction is accompanied by a large uncertainty in the final result .

Jan 1, 1964

By W. O. Vanderburg

This paper describing the methods of concentrating tungsten pros at the mills of the Atolia Mining Co. is one of a series of similar papers being prepared by the United States Bureau of Mines. The writer acknowledges the assistance and cooperation of A. V. Udell, president, Louis Warnken, bookkeeper, and C. K. Dennis, superintendent, of the Atolia Mining Co. in the preparation of this paper.

Jan 1, 1931

By C. H. Riggs

"INTRODUCTION The injection of gas into the McClosky limestone in the adjoining, Griffin and New Harmony field in Indiana and Illinois and resulting increases in oil and gas production from this zone ore described in this report.Since 1911, the use of compressed air or as to increase oil production by supplementing natural reservoir energy has been widely adopted, and has resulted in the recovery of much additional oil, which otherwise would have been left underground. In many of the newer oil fields, including Griffin and New Harmony, a part of the compressed residue gas from natural gasoline plants is returned to the reservoir as a secondary method to increase oil and gasoline production. Part of the injected gas is stored underground for future use.By presenting data on many secondary recovery operations in a series of reports 5-9/ the Bureau of Mines has sought to stimulate interest in secondary recovery as a means of increasing oil recovery and current oil production for wartime needs. Most of the elder fields in the United States produce oil from sandstone reservoirs, and probably more than 90 percent of secondary recovery operations have been developed in oil bearing sandstones. During recent years, the volume of oil obtained by primary methods from limestone reservoirs has increased steadily, but as yet little has been done to recover, by secondary means,,the large volumes of oil left in limestone reservoirs when primary methods production are no longer profitable. Because of inherent differences in the origin and nature of the pore spaces between sandstones and limestones and because of differences in permeability and fluid content, secondary recovery methods, which are successful in sandstone-reservoirs, are not always applicable to limestones. Not much he been written concerning secondary recovery operations in limestone reservoirs, and few data are available to assist operators in developing such secondary recovery projects."

Jul 1, 1945

By David E. Siskind

The Bureau of Mines studied environmental blast effects in six occupied residential structures. Airblast, ground, and structure vibrations were measured both inside and outside residences for seven quarry production blasts. Walls and floors responded to the blast noise and vibration by shaking at their own natural frequencies, often with greater peak particle velocities than the ground outside the structures or their foundations. The vibrations of the houses generated noticeable internal noise, correlating with the arrival of the groundborne energy. The later arriving airblast wave was predominantly at low infrasonic frequencies (1.0 to 1.5 Hz) and had similar amplitude and frequency characteristics both inside and out-side the structures. Significant structural motions resulted from the air-blast overpressures for at least two of the seven blasts. The most severe airblast effect occurred at a house 1,800 feet from a 5,047-pound (200-lb/ delay) blast. This stucture was subjected to a peak 0.16-in/sec particle velocity and 130 dB(L) airblast. The wall of the second floor responded to the ground vibration and airblast by shaking at particle velocities of 0.15 and 0.28 in/sec, respectively. Analysis of these data and those from additional field studies will be used to identify appropriate, safe, and reasonable impulsive noise levels, measurement techniques, and factors of design applicable to minimizing the adverse environmental effects of blasting.

Jan 1, 1976

By P. D. Lindahl

[A cost/benefit analysis was conducted by comparing the industry cost to protective structures on low-coal face equipment with the benefits paid for injuries/fatalities considered preventable by the use of these structures. Th industry costs were based on estimates by OEM's and rebuild shops for install protective structures on new and rebuilt face equipment. The accident benefit was based on evaluations performed by the USBM Accident Cost Indicator Model. Industry wide population data were developed on low-coal face equipment and injuries/ fatalities preventable with protective structures. The results of the analysis are to be used as a tool by USBM in determining the feasibility of continuing development of cab and canopy technology for low-coal equipment.]

Jan 1, 1983

By Mackenzie Burnett

A high efficiency ejector has been developed which solves the abrasion problem associated with remote pneumatic stowing. The system can also produce cemented fills. The ejector is capable of moving the fill material over 70 ft from the injection point and filling the mine opening to the roof level for a distance of about 30 ft in all directions from the borehole. This system operates by the transfer of momentum from a supersonic air stream to the fill material. The momentum transfer results in a horizontal stream of fill material and air at a velocity of about 100 fps. The ejector fits on the bottom end of a 3 in diameter vertical pipe. Fill material is fed into the ejector at a controlled rate through a hopper mounted over the borehole. High pressure air used to operate the ejector is fed through a second 3 in diameter pipe. This system has the additional feature of mixing water in the air stream which increases the potential momentum of the air stream. Where necessary, cement can be added to the gravel to create a cemented fill. The design parameters and test results for four versions of the ejector are presented in this report.

Jan 1, 1991

By C. W. Schultz

The vapor pressure of manganese in equilibrium with a series of liquid iron-manganese alloys was determined by the carrier gas method over a broad range of alloy composition. From these data the activities of manganese in the iron-manganese system were calculated. The system appears to be ideal.

Jan 1, 1966

By Walter K. Utt

The U.S. Bureau of Mines conducted research to develop an accurate, real-time, position monitoring and warning system for the vehicles used in surface mining. The product of this research will be technology to reduce accidents and injuries associated with the operation of surface mining haulage equipment. The position monitoring system should reduce accidents related to vehicle position and also increase the efficiency of haulage operations. This research was conducted in preparation for development of an accurate, real-time position monitoring and warning system, which notifies equipment operators when they deviate from a known safe course and are approaching a fixed hazard. A radar positioning system designed for marine applications was evaluated and a series of tests was run to determine the accuracy of the radar positioning system when used in a land vehicle. The radar position determination was compared to surveyed values. Both static and dynamic (moving vehicle) tests were conducted. The static test results were marginal and the dynamic test results were not accurate enough for the position monitoring and warning system. Although a promising technology, the system tested needs to be modified to meet the accuracy requirements of mobile mine equipment.

Jan 1, 2010

By Paul G. Marinos, Vassilis Marinos, Evert Hoek

The Geological Strength Index (GSI) is a system of rock mass characterization that has been developed in engineering rock mechanics to meet the need for reliable input data related to rock mass properties required as input for numerical analysis or closed-form solutions for designing tunnels, slopes, or foundations in rocks. The geological character of the rock material, together with the visual assessment of the mass it forms, is used as a direct input for the selection of parameters for predicting rock mass strength and deformability. This approach enables a rock mass to be considered as a mechanical continuum without losing the influence that geology has on its mechanical properties. It also provides a field method for characterizing difficult-to-describe rock masses. Recommendations on the use of GSI are given and, in addition, cases where the GSI is not applicable are discussed.

Jan 5, 2007

By Gary L. Hundley

As part of the U.S. Bureau of Mines program to reduce the Nation's reliance on foreign supplies for critical metals, a procedure was devised to separate and recover critical metals from mixed and contaminated super alloy scrap. The process uses both pyrometallurgical and hydrometallurgical methods to treat the scrap. The mixed scrap is converted to a matte containing 4 to 7 pct S by adding S directly to the molten metal. This matte is then granulated and ground to a minus 35-mesh particle size and leached with an HCI-CI2 solution. This process takes essentially all the Ni, Co, Cr, Fe, AI, and Mo into solution in a 3-h leach, leaving W, Ta, Ti, and Nb (Cb) in the residue. The Mo is recovered from the chloride leach solution by solvent extraction, and the Cr and Fe are recovered together by precipitation. The Ni and Co can be recovered individually by an existing solvent extraction-electrowinning process. The W is recovered by a caustic leach of oxidized Cl2 leach residue.

Jan 1, 2010

By C. F. Winquist

The Bureau of Mines is engaged in research to evaluate the effects of cutter bit wear at coal mine faces. This paper addresses one element of conical bit wear, bit rotation. A discussion on mounting configura-tion and bit forces and their effects on rotation is presented. The effects on rotation and bit forces of bit attack angle, cutting depth, and skew are determined for two types of conical bits during linear cutting of sandstone-inclusive rock. The results indicate that a 10° negative skew angle and 35° attack angle produce the maximum rotation of 17.5° for each foot of cutting. Data on bit rotation and bit forces are presented in an appendix.

Jan 1, 1985

By Walter K. Utt

The vibration levels of the heavy machines used in surface mining are much greater than for vehicles used on highways. In order to assure the proper functioning of electronic equipment placed on the surface mining vehicles, the U.S. Bureau of Mines has conducted a program of field measurements to define their vibration environment. The information in this report is for a class of vehicle that has a blade for scraping and wheels with rubber tires. The statistical information derived from these measurements can be used as a basis for laboratory testing to qualify equipment for a surface mining vehicle of this class. The envelope that would encompass 99 pct of the vibrations encountered in normal operations is presented for each location on the vehicle. The five locations for which data were recorded are the floor of the cab, the engine, the frame, the drive train (gear, differential, and torque converter), and the axle. Tabulated data are provided for those who wish to use a different probability level. The appropriate test profile for the laboratory testing can be determined from the information presented in this report.

Jan 1, 1993