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By S. P. Kinney, P. H. Royster, T. L. Joseph

An investigation of the production of iron in the blast furnace is obviously not an easy subject for research . Enough is known of the mechanical , thermal and chemical conditions existing inside the furnace to say certainly that they are complicated. Furnace operators have found that the process is sensitive to a number of known and to many unknown operating conditions . In order to form any conclusions of value , it seems necessary to collect a large amount of data taken with considerable care and accuracy. These facts make a blast furnace research difficult but not impossible . The most serious obstacle in attacking the problem comes from the fact that it is useless in the design and operation of the blast furnace to use the method of " trial and error , which has proved valuable in so many other industrial problems . The variables are so interrelated and are so dependent one on the other that the number of experimental combinations to be tried is enormous . There are certainly not less than twenty factors in furnace operation and design that are known to influence the results . This is apparent if it is remembered that a phrase like " size and shape of the furnace" includes height of the furnace , height , diameter and angle of the bosh , inwall batter , stockline diameter , and furnace volume ; and that a phrase like " chemical and physical properties of the fuels charged " includes size and shape of the lumps , density, porosity and strength of the coke , in addition to its chemical analysis . Let us suppose that we need choose for each of twenty factors one of two values , for example , suppose we must say only that the furnace shall be " tall " or " short , " that the bosh angle shall be " flat " OF "steep , that the ore shall be " coarse " or " fine , " or that the blast has to be "hot" or " cold , " the number of resulting combinations is more than one million . In putting twenty pennies on the table , either heads up or tails up, the number of permutations possible is the twentieth power of two , slightly more than one million. It is obvious , therefore , that some sort of mathematical relationship , a set of rules of thumb , laws , curves or the like , are needed . Whether the relationships , curves or formulas are derived from experiment , from theory, or from mere guess -work, makes no difference provided they agree with the known facts . If they do not agree with known facts , they are worthless no matter what their origin or how weighty the " authority" vouching for them. Few such relationships have appeared in blast- furnace literature , and it may be doubted whether such formulas can be discovered .

Sep 1, 1923

By M. P. Ristenbatt, E. K. Holland-Moritz, K. Metzger

A new post-disaster signalling system for the Bureau o Mines, using through-the-earth EM propagation, was successfully field-tested in the Lake Lynn test mine. Successful detection at an estimated input SNR of -30dB was accomplished using a coherent integration time of 4.46 minutes. The transmitted waveform consisted of a repeating pseudonoise maximal length sequence phase modulating a 1950Hz carrier. The receiver used a sliding-window matched filter, optimal for signal known exactly except for phase and starting time, implemented via a special purpose processor. Parallel processing permits adaptive signalling, where the detection (integration) time is determined by the actual input SNR encountered. This field test demonstrates a trapped miner detection system that is about 36dB more sensitive than a current pulsed system. This increased sensitivity permits some desired combination of increased range, shorter detection time, and reduced transmitter power or antenna-size. The combination of pulse-compression-type-signal, coherent integration, parallel-processing, and output peak-detection algorithms permit implemention of an ultra-reliable detection system. The same combination is compatible with digital Pulse Position Modulation and Emitter position location strategies.

Jan 12, 1983

By Joan T. May

The Federal Bureau of Mines investigated the potential for recovering aluminum from copper-dump leach liquors by use of single-contact ion-exchange technology. A strongly acidic ion-exchange resin was used to extract aluminum from a typical dump leach liquor and from synthetic leach liquors. Aluminum was stripped from resin with a HS04 or NaCl solution. Bench-scale experiments indicate that a single-contact ion exchange is technically feasible, but that the process is limited by the relatively low loading capacity of the resin and the excessive amount of stripping agent required. A further limitation is that significant amounts of magnesium and iron are loaded and stripped along with the aluminum.

Jan 1, 1976

By A. R. Kirchner

This paper describing the practice at the concentrator of the Minas de Matahambre, S. A., is one of a series being; prepared by the Bureau f Mines on milling methods and costs. The Minas de Matahambre, S. A., concentrator treats the production of the Matahambre mine and has a capacity of 1,300 tons of copper ore per day by selective flotation. During the year 1930 the heads averaged 4.55 per cent copper, the concentrates 29.20 per cent copper and the recovery was 95.96 per cent.

Jan 1, 1931

By H. G. Iverson

The purpose of this investigation was to beneficiate the Talladega gray iron ores by flotation. A component of the problem was the determination of the degree of beneficiation possible by flotation as well as the relative selectivity of certain reagents in promoting flotation of either the iron minerals or the siliceous gangue minerals. The scope of the present investigation involved only the use of small-scale laboratory equipment. Treatment by roasting and magnetic separation was not included in this study, inasmuch as a similar comprehensive investigation was completed and the results were published by the Bureau of Mines in 1927. The results of the work on Talladega iron ores are briefly summarized in this report. In the search for efficient and economic methods of beneficiating low-grade iron ores, the flotation process is among those that are receiving considerable attention. The Talladega ores are of particular interest for a flotation study, because they contain two iron minerals (magnetite and specular hematite) that are somewhat dissimilar in their flotative response.

Jan 1, 1949

By R. T. Johansen

A gradual decrease in injection rates commonly occurs as a water-flooding project becomes older. This decrease can be attributed to changes in reservoir conditions, such as swelling of clay minerals, fillup, or gradual plugging of the sand face. However, a rapid decrease in the rate of injection indicates abnormal behavior and is cause for alarm. Extreme plugging conditions can completely stop injections into a formation. Such behavior in wells was the main concern of the tests described in this report. An accepted method of alleviating this condition is by backflowing input wells - closing the supply lines to the wells and allowing the reservoir pressure to force water back into the wellbore and to the surface. If backflowing is not successful, a string of smaller diameter pipe sometimes is run inside the casing, and the sand face is flushed with a waterspray. More drastic treatment is to inject acid into the wellbore to dissolve extraneous matter, or even part of the reservoir material, in an attempt to restore the permeability of the sand immediately around the wellbore. Any of these procedures can he coordinated with bailing and swabbing of the well for cleanout purposes.

Jan 1, 1957

By E. D. Gordner

U. S. Bureau of Mines

Jan 1, 1923

By J. A. HUFF, V. V. BAKER

This circular contains a statement of the statutory provisions of the several States regarding the appointment , qualifications , and remuneration of State mine inspectors . States have been omitted where no specific provision has been made by the State law for mine inspectors .

Jul 1, 1931

By K. E. Tame

The Bureau of Mines is studying possible modifications in conventional uranium ore-processing steps to confine and permit controlled disposal of radioactive wastes. Surveys of Ra226 contamination of liquid wastes from uranium mills indicated that the Vanadium Corporation of America plant at Durango, Colo., had one of the more urgent problems. A possible procedure for minimizing the waste disposal problem was to reuse the waste solution in the mill--in effect, erasing the need for disposal of liquid waste. In examining this possibility, interlocked bench-scale leaching and solvent extraction tests simulating the Durango flowsheet were made. The simulated reuse of barren raffinate for leaching and washing was carried through three separate campaigns of 9, 12, and 35 cycles each.

Jan 1, 1961

By G. W. Jones

An important activity of the Bureau of Mines is the promotion of safety in mining and industry. As a part of this program, the Bureau determines the explosion hazards of combustible gases, vapors, and solids and investigates means of controlling and preventing explosions. The limits of inflammability (explosive limits) of combustibles are not only of theoretical but also of practical importance, because many industries at one time or another contend with explosive mixtures of combustible gases or vapors in their manufacturing processes. At present many new organic compounds are being manufactured, transported, and used in huge quantities which a few years ago were only laboratory curiosities.

Jan 1, 1941

By G. W. Jones

An important activity of the Bureau of Mines is the promotion of safety in mining and industry. As a part of this program, the Bureau determines the explosion hazards of combustible gases, vapors, and solids and investigates means of controlling and preventing explosions. The limits of inflammability (explosive limits) of combustibles are not only of theoretical but also of practical importance, because many industries at one time or another contend with explosive mixtures of combustible gases or vapors in their manufacturing processes. At present many new organic compounds are being manufactured, transported, and used in huge quantities which a few years a ago were only laboratory curiosities.

Jan 1, 1941

By B. K. Shibler

During the investigation of the occurrence of manganese deposits in the Western United States, examining engineers of the Bureau of Mines collected 2-ton samples from five manganese properties near Golconda, Nev. Extensive laboratory tests were made to determine the amenability of these ores to standard ore-dressing methods of concentration. The Tom Major property, one of those sampled, is situated 12-1/2 miles south of Golconda, Humboldt County, Nev. The deposit is described as a bed about 5 feet thick in a thinly bedded shale and dolomite formation. The sample tested was obtained from the manganese bed, but the examining engineer reported: "The mining of an appreciable tonnage at reasonable cost would perhaps cut in half the grade represented by the sample."

Jan 1, 1951

By G. B. Goodman, W. H. Pailes, P. D. Kaplan, I. Stachura, V. Castronova

"The risk of developing silicosis in underground coal miners, tunnel workers and some foundry workers is well-known. These persons generally develop the classic form of the disease over a prolonged period of time. Workers involved in abrasive blasting of bridges and those polishing tombstones have been reported to develop an acute form of silicosis within a few years of commencing exposure. Not well-appreciated is the potential for development of acute silicosis among drillers at surface coal mines. We report the case of a 33-year--old man who worked primarily at surf ace drilling, developed acute silicosis within three years of beginning exposure, and who initially responded dramatically to corticosteroid therapy. CASE REPORTThe patient is a 33-year-old white man who worked as a rock driller at a quarry and also at surface coal mines in western Pennsylvania since 1975. Prior to 1983, much of his work was done with a wet process in which water was applied to reduce dust generation. After 1983 he worked primarily as a driller at a surface coal mine using a dry process. He never wore a respirator. He described the dust as being so dense that he ""couldn't see anything.- In August 1986, he presented to his local physician with a complaint of pleuritic chest pain and shortness of breath. A chest x-ray film was obtained showing only a few p and q opacities. He continued working and these symptoms subsided, but the patient noted the onset of progressive weight loss. By May 1987, he had lost approximately 50 lb. In addition, he suffered profound malaise, dyspnea, migratory chest pain and arthralgia, fevers and drenching night sweats.A course of erythromycin therapy given in the hospital resulted in only fleeting improvement. Studies for Legionella and Mycoplasma infections were negative, as was a tuberculin skin test. The patient was transferred to Allegheny General Hospital in Pittsburgh on June 4, 1987.There was no history of serious medical illness, including tuber¬culosis. The patient admitted to smoking between I and 1 1/2 packages of cigarettes daily for 2 1/2 years prior to May 1987 when he stopped smoking. He denied intravenous drug abuse, homosexual activity or receiving transfusions of blood or blood products.On physical examination the patient was a thin, febrile white man who appeared chronically ill. Bilateral axillary and cervical lymphadenopathy was present. Chest examination showed restricted expansion and bilateral crackles. Examination of the heart and abdomen disclosed no abnormalities."

Mar 1, 1992

By A. D. Garman

This paper presents one of a series of digests of foreign mining legislation and court decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of Colombia has been prepared from the best available information in Washington, but is released subject to correction and amplification; if necessary, by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State. SYNOPSIS OF LAW Minerals in Colombia belong to the owner of the soil unless otherwise provided in the law. The following lands and deposits, however, are described as fiscal property of the State: Class 1. The public lands, mines, and salines which belong to the individual States (now Departments) prier to the adoption of the present constitution (1886).

Jan 1, 1929

By G. W. Weems

The Bureau of Mines combined preconcentrating techniques and mass spectrometry to develop a parts-per-billion general analysis of impurities in helium. The impurities are preconcentrated using a Bureau trace-impurity analyzer; 35-mm Hg pressure of helium is left in the concentration trap to sweep the impurities into the mass spectrometry and provide a 10-mm Hg sample pressure.

Jan 1, 1966

By C. A. Komar

Renewed interest in the underground gasification of coal evolves from comprehensive studies of earth fracture systems that indicate that the movement of fluids can be controlled in the coalbed. In particular, directional property studies of natural microfissure occurrence, permeability, ultrasonic velocity, tensile strength, and orientation of intervals of inherent rock weakness, together with geologic structure setting and fracture trace analysis, can predict the gaseous flow paths in the coalbed. Having this information, the dominant direction in which gases generated and/or liberated by heat would move can be determined so that appropriate well patterns can be developed. Together with advances made in drilling technology that permit long horizontal holes to be drilled through the coal seams, tests can be conducted to determine whether directional control will permit devolatilization of the coalbed and gasification of the remaining hot coke in a systematic manner to produce a low-Btu gas suited for the generation of electricity.

Jan 1, 1973

By J. E. Murphy

The high-purity thorium metal was prepared by the Bureau of Mines from electrolytically produced thorium alloys. The thorium-chromium and thorium-manganese alloys were separated into the component elements by vacuum distillation. Chromium and manganese impurities remaining in the thorium metal after distillation at 1,850° C were <0.005 weight-percent. Removal of volatile impurities such as aluminum, calcium, magnesium, and lead was also accomplished.

Jan 1, 1969

By D. J. Stoops

The object of the research described in this paper was to investigate the effect of metallurgical and surface treatments on the corrosion behavior of arc-melted reactor-grade zirconium in cupric or ferric chloride solutions. An apparatus was constructed and specimens of various metallurgical conditions and surface treatments were tested for 6 days at 35° C., with aeration. Some correlations were observed between corrosion rate and the metal&apos;s condition and treatment, Specifically, the unattacked or least attacked specimens were those that had been etched as a final treatment before testing. The most severely attacked specimens were those that had been vacuum-annealed as a final treatment before testing. The moderately attacked specimens were those neither vacuum-annealed nor etched, but having a final surface treatment which left a cold-worked surface. Attack by cupric and ferric chloride was by pit- ting with no preference for grain boundaries, The corrosion scale was cow posed predominately of very fine zirconim particles, Particles from the FeC1,-corroded specimens were more pyrophoric than those from CuCl2-corroded specimens, and appeared to have a higher surface area to volume ratio. Comparison of results to those of previous investigators showed that at certain salt concentrations the more pure, reactor-grade zirconium was quite resistant to attack while the less pure, graphite-melted zirconium was severely attacked.

Jan 1, 1962

By C. A. Allen

"The problem of signaling to the hoisting engineer from a moving cage in the shaft has been considered by many mine operators for a number of years. There are several methods in use in different mining districts, and so far as the writer is aware they have been further developed in Utah than in any other state. The latest installations are of interest because they use a very low-voltage circuit for the shaft wires and also because the wiring can be so arranged that the hoist can be stopped from the cage, if so desired.The first installation in Utah was in the shaft of the Centennial-Eureka mine under the management of C. E. Allen. It was placed in operation in the summer of 1899, end has been in continuous and satisfactory operation for 21 years. The arrangement consists or two bare wires down the shaft carrying a current at 60 volts potential, with a device on the cage for making connection between the two wires. This device is simply a short piece of wire which is thoroughly insulated from the cage and is operated by a short lever. Whenever the cage rider wishes to signal the engineer he pulls down the lever, forcing the short wire out against the two bare wires, thus making a circuit which rings the bell in the hoist-room. A similar device was planned in the Grand Central shaft at Mammoth, Utah, but was later abandoned. The cause of failure was reported to be that the shaft was very wet."

Jun 1, 1920

By L. C. IlsLey

"Nearly every piece of electrical equipment used in mines ""breathes."" In other words, motors, controllers, rheostats, switches, and other similar equipment, even though encased in seemingly tight compartments, breathe in the atmosphere that surrounds them.As the apparatus is used, the temperature of metallic parts is changed generally in positive direction through the heat by friction and the heat due to the electric current. When the apparatus is idle it gradually cools down to the temperature of the surrounding atmosphere.This increase of temperature during operation and return to normal temperature when operation stops alternately raises and lowers the temperature of the atmosphere within the compartments which, in strict accordance with Charles' law -will expand or contract in proportion to any given temperature change.As compartments are not gas-tight, such expansion and contraction will force the atmosphere out of the compartment =on expansion and suck the surround¬ing atmosphere into the compartment during contraction, hence the term ""breathing.""Investigators2 of explosion-proof equipment have recognized that such an interchange would take place and have designed their equipment to safeguard possible explosions within the compartments."

Jun 1, 1927