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By Robert D. Harris

In 1958, the coal industry, through Bituminous Coal Research, Inc., and the electric utility industry, through the Edison Electric Institute and the Association of Edison Illuminating Companies, initiated a joint program to study coal pyrite and its removal as a means of lowering the sulfur content of steam coals. It was assumed that significant amounts of pyrite often remained in washed steam coal not because available systems for coal cleaning were inadequate, but because the pyrite was small and widely disseminated, During the first two years, samples of coal were examined petrographically to determine the size, association, and mode of occurrence of the pyrite in the raw coal and in the products of laboratory separation, Samples of coal were also pulverized in different equipment to determine how effectively pyrite was released by pulverization and if the mode of pulverization affected the liberation of pyrite. From these studies, the following tentative conclusions were made (1 ): 1. Much of the coal pyrite is within a 250-70 micron size range, and therefore is too small to be removed by conventional coal cleaning, but relatively large when compared to the size of coal as pulverized for combustion in large boilers. 2. The degree of pyrite liberation is mainly determined by the size of the product and not by the type of crusher. 3. For improved pyrite removal, the coal should be cleaned during or after pulverization at the power station.

Jan 1, 1965

By J. P. Baur

The sensitivity of radiochemical techniques makes possible the study of the initial stage sulfuric acid leaching kinetics of chalcopyrite and other copper sulfide minerals. High-grade Transvaal chalcopyrite was neutron irradiated in a TRIGA reactor to produce radioisotopes copper-64, iron-59, and sulfur-35. Dissolution rates were measured in the time interval zero to 60 minutes during which time significant anomalies were observed. First, an initial period of rapid dissolution lasting a few minutes; second, an arrest or "plateau" region usually lasting from 6 to 10 minutes; third, a second period of dissolution of lesser rate than the first. The effect of solution variables such as pH, oxygen partial pressure, and ferric ion concentration at different temperatures were measured. The initial rate data were correlated by considering the rapid reaction to be due to the dissolution of surface oxidation products or the formation of an iron depleted surface layer. The data for the second slower reaction have been explained to be due

Jan 1, 1972

By R. G. Dressler

The Federal Bureau of Mines designed, constructed, and operated a demonstration plant at Louisiana, Mo., to produce gasoline, liquid fuels, and organic compounds from coal by a modified Fischer-Tropsch gas-synthesis process. Satisfactory equipment was developed to produce and purify synthesis gas and convert it into the desired products. Coal or coke was gasified with oxygen and steam to make a gas consisting essentially of carbon monoxide, hydrogen, and carbon dioxide. Dust in the raw gas was removed by cyclone separation, water scrubbing, and electrostatic precipitation. Carbon dioxide, hydrogen sulfide, and organic sulfur were removed with diethanolamine, iron oxide, and activated carbon. The gas was passed over iron catalyst and was converted into synthetic liquids, which were then separated and fractionated into gasoline, diesel oil, other liquid fuels, and oxygenated organic compounds. A 39-day continuous run demonstrated the feasibility of the process. Addition of 3 milliliters of tetraethylead per gallon of upgraded (or finished) gasoline gave a product with an octane rating up to 90 by the research method. After a caustic wash, the diesel oil was of a superior quality; its cetane number was 60 or above.

Jan 1, 1961

By J. HUNER

Twenty-four new fields were found in Louisiana during 1945. Of this number 15 were oil fields, eight were gas condensate, and one a dry gas field. None of these fields, with the exception of West Delhi, is as yet of any great consequence. The Weeks Island field in Iberia Parish may eventually develop into a considerable reserve.

Jan 1, 1946

By William Y. Mo

This report presents preliminary results of a study undertaken to investigate quantitative characteristics of the demand for steel mill products and its major end-use components. The major end uses included in the study are the steel mill products used in construction, in automobiles, in producer durables, and in consumer durables. The main objectives of the research underlying this study are as follows: (1) To formulate and estimate the empirical demand relations for steel and the four major end uses in the United States; (2) to measure and calculate the responsiveness of the U.S. per capita steel consumption with respect to the changes of the steel and other nonferrous metals prices; (3) to determine and quantify the relative importance of the underlying demand explanatory factors in contributing to the average year-to-year increases (or decreases) of the U.S. per capita steel consumption; and (4) to adapt and use the estimated demand relations in making projections of the U.S. future demand for steel and the major end-use components. After extensive preliminary investigation, three versions of simple linear demand relations are selected and estimated by means of ordinary least squares (OLS) method. The annual data for the period 1947-65 are used in the estimation. Direct and cross price elasticities of demand are computed for each of major end uses. The relative importance of demand explanatory factors in contributing to the average year-to-year changes of U.S. per capita steel consumption are also calculated. For making projections, a simple autoregressive time trend model is used in estimating the future values of independent variables. Since the estimated demand relations are valid for projections only if the estimated parameters can be assumed to be unchanged in the future, and consequently, the projections derived in the study should be interpreted accordingly.

Jan 1, 1970

By J. P. BONARDI, C. W. Davis, R. B. Moore, J. W. MARDEN, S. C. Lind, J. E. Conley

The rare metals are becoming increasingly important to our industries. Rare-metal alloys have properties which indicate that we are only on the threshold of the possibilities of their utilization, not only in making nonferrous alloys, but also as special steels. Not only are their uses broadening rapidly, but the metals are affecting our industries in other ways. The oxides and some salts are used as pigments; others have medicinal value. The pure metals are made into filaments for incandescent lamps, and targets for X-ray tubes. By their efficient use in alloys, the weight of automobiles is reduced, • and the wear and tear on tires and roads is thus minimized; in machine shops they help to give greater efficiency to tools and reduce production costs. Their development has marked a milestone in the progress of civilization. There has been considerable uncertainty regarding analytical methods for the rare metals. A great deal has been published, but the weak and the strong points of the various methods have not been investigated as carefully as is needed. The Bureau of Mines at its Rare Metals station in Colorado necessarily had to do a great deal of analytical work in connection with the metals covered by this bulletin, which aims to give the results of the experience so acquired. No claim for much originality is made, although some published methods given have been modified, and some new ones have been developed by members of the staff. The principal methods available were studied critically, and it is to be hoped that the work will assist those interested in analytical work in connection with the metals named.

Jan 1, 1923

This is the fourth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-363/. The second report gave the same data for motor gasolines sold during the summer of 19363/. The third report of the seriis gave the same data for motor gasolines sold during the winter of 1936-375/. This report covers 63 brands of gasoline represented by 1,136 samples excluding the Pacific Coast. Those from the Pacific Coast were averaged by the Pacific Coast technical group before being submitted and are published exactly as they were submitted. In some areas reports were received from five or six companies on the same brands of gasoline, whereas in other areas only one company reported on a brand. Thus, it can be seen that some of the data are more representative that others.

Jan 1, 1937

This is the fourth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-363/. The second report gave the same data? for motor gasolines sold during the summer of 19364/. The third report of the series gave the same data for motor gasolines sold during the winter of 1936-375/. This report covers 63 brands of gasoline represented by 1,136 samples excluding the Pacific Coast. Those from the Pacific Coast were averaged by the Pacific Coast technical group before being submitted and are published exactly as they were submitted. In some areas reports were received from five or six companies on the same brands of gasoline, whereas in other areas only one company reported on a brand. Thus, it can be seen that some of the data are more representative than others.

Jan 1, 1937

By E. M. Frizzell

Development of mobile crusher systems for surface mining, allowing extension of continuous conveyor haulage systems into the pit, is traced from its introduction to the present. Variations in configurations are reviewed, and the compelling reasons for using mobile crusher systems are explored.

Jan 1, 1983

By Charles G. Maier

"INTRODUCTION The use of thermodynamic calculations to answer practical problems in metallurgy, especially those that are relatively difficult to test experimentally, is rapidly becoming a conventional method of procedure. Nevertheless, these methods cannot he applied effectively until the fundamental thermodynamic constants used for them have become available either by direct experiment or by recalculation of data already existing in more or less undigested form.In an attempt to collect such data far the compounds of lead and the antimony group the incentive has been to make a preliminary survey that will disclose the gaps or questionable phases of available information and to collect data that may be used to answer certain rather practical problems presented by operating metallurgists.This report comprises three sections; the first gives the basis of selection of the constants which may now be given or estimated, and the later sections discuss the application of the figures obtained to two of the more interesting problems.The reader will discover that many of the quantities involve critical study of a number of more or less discordant observations. Although certain data could be rejected on the basis of thermodynamic comparisons, it must not be overlooked that many of the figures are the results of rational estimates rather than exact experiment. The use of thermodynamic methods to control and partly authenticate such estimates is one of its most valuable characteristics for the practising metallurgist or chemist, who cannot check by direct experiment each property of the materials which he converts to usable form.Nevertheless, while it is definitely possible in certain instances that the final figure selected for the heat or free energy of a process or substance may be in error by as much as a few hundred to a few thousand calories per formula weight, questionable figures are usually revealed by the thermodynamic calculations made. When quantities of such degree of accuracy are, and they often must be, used for estimating an unknown reaction, the result often gives no more than the order of magnitude of the desired quantities. Yet even in these extreme cases the answer is far more reliable and valuable than an unordered guess or a conclusion based on incorrect data."

Dec 1, 1934

By Arnaud Faucher, Amar Sabih, Sudarshan Martins, Tristan Martin, Sami Makni, Peter Radziszewski, Poorya Hosseini, Francois-Raymond Boyer

The measurement of acoustic signals produced by a tumbling mill has been previously used to determine the operating state of the mill and correlate the variations of the sound intensity with the operating conditions of the mill. Separately, the discrete element model (DEM), a software simulation of the mill, was developed to provide insight into the operation of the mill. Presently, there has not been much work reconciling the DEM simulation of the mill with the acoustic signal. Working from basic principles of linear, time-invariant systems, agreement between an acoustic DEM simulation and the measured signal is sought. First, the impulse response function of the mill is measured. The DEM provides the forces applied to the mill shell as a function of time. A convolution of these simulated shell forces and the transfer function gives the simulated acoustic signal. This signal is compared to the measured acoustic signal, both in the time domain and the frequency domain. Finally, a discussion of the results is given.

Jan 1, 2012

By G. L. Oldright, Virgil Miller

"This paper is the eighth; of a series on smelting in the lead blast furnace, and the third' of a group on the modifications brought about by the introduction of rich charges.ACKN0WLEDGMENTSThe data that appear in these articles were obtained through the courtesy of the operators of the Bunker Hill smelter at Kellogg, Idaho. The authors take this opportunity to express their appreciation to Stanley A. Easton, the vice-president and general manager, Frank M. Smith, smelter director, and to A. F. Beasley, the smelter superintendent, and his staff.INTR0DUCTI0NIt has been noted that the gases issuing from the top6 of the charges in the International Smelting Co.'s furnaces at Tooele, Utah, were very similar in composition to the gases from the top of the iron blast furnace, as they contained about 26 per cent of CO and 12 per cent of C02, the rest of the constituents being mainly nitrogen with a very little hydrogen and oxygen. It has been seen that where the column of coke was sufficiently high, the production of C0 gas to carry out the reduction of lead ores was accomplished in about the same manner as in a gas producer. In some cases, there was a little oxygen in the ""top gas"" -- usually not over a few tenths of a per cent, but at times amounting to several per cent. The presence of this gas was attributed to irregularities in operation that permitted air to come up through the tuybres to the surface without meeting any coke that was incandescent. Only a hundredth of a per cent or so of sulphurous oxides was present in the gases issuing from the top of the furnace."

Apr 1, 1931

Research 82 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information, 2401 E Street, NW., Washington, D.C. 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1982

By Michael F. Dunn

Since crushing of rock to a smaller size is an integral part of almost any mining and quarrying operation, a study was carried out to identify and develop improved techniques for alleviating a major cause of accidents and work stoppages arising when an oversize luck or boulder lodges in the throat of the crusher. The configurations and operations of various crusher types is described, sources of boulders in the mining operation, and a detailed review is made of mining, quarrying, and construction regulations for all states, Canada, and the Federal Government for applicable provisions. Representative mines were visited and other operations contacted for their boulder handling techniques where it was found that blasting techniques used included mudcapping, bombs, and blockholing, often done very crudely and inefficiently with poor practices and various mechanical systems were used such is hooks of, overhead cranes, impact hammers, and grapplers. Safety analyses of all methods pointed out the hazards associated with blasting in the open and the dangers of entering a crusher. Boulder blasting can be done in a safer fashion if a planned step-by-step procedure is followed, and inherently safer blasting products such as exploding bridge wire blasting caps and improved blockholing techniques. In general, though, the installation of a suitable mechanical system such as an impact breaker will prove safer and cost effective even in a smaller mine or quarry.

Jan 1, 1981

By Venancio Astucuri

"El presente texto describe las cuatro competencias que debe poseer un ingenierio de minas para un desarrollo sostenible de la minería. Dichas competencias se dividen en personales, académicas, profesionales y de ingeniería. Este grupo de competencias pueden ser usados también para un proceso de autoevaluación, donde cada uno pueda medir sus competencias con el fin de determinar brechas y superarlas, de forma que las empresas puedan plantear requisitos mínimos para sus diferentes posiciones laborales y, finalmente, para que en las instituciones educativas, estos puedan diseñar de forma adecuada sus respectivos planes de estudio."

Feb 1, 2017

By A Kamaraj, M Mohanasundaram, R Kumar, P Tikare

This study presents a comprehensive thermodynamic optimisation and sustainability analysis of the secondary copper smelting process for Waste Printed Circuit Board (WPCB) recycling. The study investigates various scenarios with different proportions of WPCB in the input stream, ranging from 0 per cent to 100 per cent. Through thermodynamic modelling using FactSage™ version 8.1, the optimisation process is conducted in three stages. The results of the thermodynamic modelling indicate that the best-case scenario for WPCB recycling is achieved with a 40 per cent proportion of WPCB in the input stream. This case exhibits a maximum copper recovery of 99.93 per cent while minimising the formation of other waste. In addition to the thermodynamic analyses, environmental factors such as the carbon emission index and resource utilisation efficiency are studied. The 40 per cent WPCB recycling case exhibits a resource utilisation efficiency of 93.055 per cent and a carbon emission rate of 0.133. The present investigation highlights the significant benefits of a 40 per cent WPCB recycling scenario through a secondary copper smelting process in terms of base metal recovery and energy efficiency, thus emphasising its potential for sustainable PCB waste management and resource utilisation.

Aug 21, 2024

By L. Bichler

Utilizing thermal analysis techniques, pioneering research into the solidification mechanism of a popular magnesium alloy AZ91E cast by the Lost Foam Casting (LFC) process was carried out, Foam characteristics, section thickness and application of vacuum were seen to have profound effect on the cooling rate, thermal gradients and casting temperature profiles.

Jan 1, 2005

By Fred Hodges

This paper describing the concentrator practice of the Hurley Plant of the Nevada Consolidated Copper Co. at Hurley, N. Mex., is one of a series of papers on milling methods and costs being prepared by the United States Bureau of Mines. The Hurley concentrator has a normal daily capacity of 13,500 tons of ore, and for the first four months of 1930 the heads of the concentrator averaged 1.32 per cent of copper and 3.14 per cent of iron. The recovery for this period was 83.98 per cent and the concentrates produced averaged 27.54 per cent of copper.

Jan 1, 1931

By Xinghui Meng

The leaching behavior of platinum powder in .iodide solutions under oxygen pressure in an autoclave was investigated. Ammonium salts were added to the leaching solution at neutral pH as a key lixiviant for platinum. The effect of temperature, partial pressure of oxygen, concentration of iodide and of arttmonium salts on the dissolution rate of platinum was examined. Under experimental conditions, the leaching behavior of platinum powder exhibited a complex reaction mechanism. A precipitate was found during the leaching process and was identified to be platinum ammine iodide, Pt(NH3hI4. The dissolution rate was controlled by a series of chemical reactions, the equilibrium concentration of the platinum ammine iodide being responsible for the ultimate limit to the recovery.

Jan 1, 1996

By E. G. Meiter, S. H. Katz

"Railroad locomotives produce heat, gas, and smoke, which cause considerable discomfort to engine men and firemen while passing through tunnels. In order to try and improve these conditions, the Bureau of Mines has investigated the composition of atmospheres in cabs of freight locomotives while in tunnels; and some of the higher temperatures in the cabs were noted; physiological effects upon men were determined and gas masks and respirators were devised to eliminate the effects of irritating and poisonous gases and smoke. Those investigations were conducted in tunnels of the Baltimore & Ohio, Pennsylvania, and Union Pacific railroads; while that described in this paper was carried out in tunnels of the Chesapeake & Ohio, Railroad, situated in the Blue Ridge and Allegheny Mountains in Virginia and West Virginia, Freight locomotives used by this railroad are of the Mallet type, which have two separate cylinders: and two separate sets of driving wheels on each side. In locomotive language they are of the 2-6-6-2 type. All of the cylinders act as simple engines when starting or in slow, heavy hauling; but at faster speeds the pair of cylinders on each side operate compound, Mallet locomotives are the largest and most powerful now operated.The tendency in train operation has always been to increase the burden upon locomotives, Present traffic needs frequently load even the Mallet engine to capacity, and yet the weight of trains tends to increase. It has been suggested as a means of securing greater power units that Mallets be constructed to operate only as simple engines. This would increase the amount of steam given off as the amount of coal burned and the resulting volume of flue gas emitted."

Jul 1, 1924