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By A. D. Mah

To assist Bureau of Mines research in extractive metallurgy and to add to the thermodynamic data base useful to others, energy calculations were made for 63 reactions relating to investigations on the production of anhydrous aluminum chloride from chlorination of clay.

Jan 1, 1982

By James C. Barker

Alluvial cassiterite concentrations are widespread in river gravel and high level terraces within the Ray River watershed. The area lies in unglaciated terrain of Alaska's northern interior. Cassiterite originates from several calc-alkaline plutons of the Ruby batholith. Extensional stresses resulted in graben-like Tertiary basins that were flooded by a 200 ft thick section of mid-to late- Tertiary basalt flows. Basalt blocked local drainages, and 50- to 100-ft of terrace gravel was eventually deposited on top of the flows. Further downwarping and eventual fluvial downcutting of the flows resulted in cycles of accelerated sediment transport, deposition, and reconcentration. Repeated erosional cycles concentrated heavy minerals and resulted in development of tin placers. Preliminary resource estimates of contained tin in Recent alluvium range from 62 to as much as 172 million lbs-Sn in 300 million yd3. Grade of about 90% of the gravels is estimated to range between 0.2- to 0.5- lbs-Sn/yd3. Associated gold and rare earth elements (REE) in monazite and xenotime may be recoverable. Most of the tin is considered a subeconomic inferred resource, though, at least some of the gravels contain 2-to 6-lbs-sn/yd3. Estimates are projected on the basis of surface sampling and several auger drill holes and are provided for the purpose of land-use management planning.

Jan 1, 2011

By P. H. Mutschler

The Bureau of Mines studied the Chattanooga Shale to determine the quantity and quality of the uranium resources present and to assess specific environmental effects of mining the shale. Geologic data and chemical analyses, mainly concerning a 12-county area of Tennessee, were compiled from previous published and unpublished reports. Uranium resources in the Gassaway Member of the Chattanooga Shale in this 12-county area were estimated to be between 4.2 and 5.1 million tons, contained in 76 to 91 billion tons of shale. These figures represent inground tonnages and do not allow for mining or processing losses. Depending upon efficiency of mining and processing systems, enough uranium could be available to satisfy a large part of the cumulative domestic and world demand through the year 2000. A model was developed which assesses the total tons or acres of shale to be mined if the Gassaway Member were to satisfy 1 percent of the United States demand for uranium in 1991. This partially demonstrates the environmental impact of mining the shale and is easily factorable to any specified demand.

Jan 1, 1976

By Lester G. Morrell

While developments in Australia dominated the minerals industry of the South Pacific area, New Caledonia's nickel, manganese ore from New Hebrides, gold from Fiji and New Guinea, and phosphate rock from several small islands were significant in world supplies of those materials. The total value of mineral commodities produced in this area in 1965 has been estimated at about $763 million an increase of nearly 16 percent over the value reported in 1964. Increases were recorded in mineral production value with respect to that of 1964 for all of the countries except Papua-New Guinea where lower gold output resulted in a drop of about $300,000 and in the several phosphate-producing islands that collectively recorded a value decline of around $1.3 million. Exploration and development activities continued at an intensified level, not only in Australia and New Zealand but also in the British Solomons, Bougainville, and Fiji. Substantial additions to world supplies of iron ore and bauxite are assured and recent discoveries of natural gas, manganese ore, and nickel combine to give Australia a brilliant mineral outlook. Important discoveries of copper on Bougainville Island and on Vanua Levu, the north island of the Fiji group, and a gold mine on Misma Island were being developed during the year, with plans for early production underway. In New Zealand progress has been made on the New Zealand Steel Company project, and preliminary appraisal of a new titano-magnetite beach sand resource on the South Island has aroused considerable industrial interest. Extensive geophysical investigations were carried out in the British Solomon Islands and on Fiji's goldfields. The expansion program that will double output of products by New Caledonia's Société Le Nickel continued through 1965, and several foreign private companies have expressed a desire to initiate additional industries based on nickel prospects in New Caledonia.

Jan 1, 1967

By Frank A. Peters

This Bureau of Mines report is the second of a series of process evaluations planned to determine the relative processing costs of producing metallurgical-grade alumina from low-grade aluminous materials. Included in these evaluations are recommendations for additional research and development to improve the processes and to lower their costs. The design for each process is based on published work. The processes considered in this report are designed to extract alumina as aluminum chloride from calcined clay with 20 percent hydrochloric acid and to remove the silica residue by filtration. Iron is removed by one of the following processes: Isopropyl ether extraction, in which iron chloride is extracted before decomposing the aluminum chloride; gas precipitation, in which the aluminum chloride is precipitated with hydrogen chloride while leaving the iron chloride in solution; gas precipitation-isopropyl ether extraction, in which the aluminum chloride from precipitation is extracted with isopropyl ether, if necessary; caustic purification, in which a crude alumina is produced and then purified by a modified Bayer operation; or sinter purification, in which a crude alumina is produced and then purified by a lime-soda sinter operation. For plants producing 1,000 tons of alumina a day the estimated operating costs per ton of alumina are: [Isopropyl ether extraction process $ 65.09 Gas precipitation process 89.04 Gas precipitation-isopropyl ether extraction process 119.65 Caustic purification process 73.79 Sinter purification process 80.47] The estimated fixed capital costs per annual ton for these plants on a Marshall and Stevens chemical equipment basis of 240.0 are: [Isopropyl ether extraction process $229.03 Gas precipitation process 287.16 Gas precipitation-isopropyl ether extraction process 356.59 Caustic purification process 266.48 Sinter purification process 279.13]

Jan 1, 1962

By R. B. Ladoo

"Present Situation:At the beginning of 1920 a general feeling of optimism was noted in many talc-producing districts. The industry seems to have recovered from the temporary depression of the first half of 1919 and many mills are running at capacity production with their entire output for 1920 contracted for. The imports of talc for 1919 were only slightly larger than in 1918 by weight and probably no more by value. Thus foreign competition has not begun to be seriously felt. Several new companies in this country have been organized, some to operate new deposits and others to continue the work done by others.An interesting phase of the present situation is the possibility of increased use of talc in paint. There is a shortage of barium sulfate used as a paint filler. Since, for some uses, talc is considered second only to BaSo4 as a filler for paint, it is possible that part of the shortage could be relieved by an increased use of talc.A series of physical tests upon all pigment materials used in the manufacture of paints is being conducted for the Paint Manufacturers Association of the United States. It is important that all types of talc be represented in these tests. Producers of finely ground talc, 200 mesh and finer, are urged to submit samples of at least two pounds each of these grades that are available to paint makers with trade name and quality data, to the Institute of Industrial Research, 19th & B Streets, N. W., Washington, D. C., where the tests are being conducted."

Jan 1, 1920

By P. A. Cox

Guidelines are provided for the design of explosion-proof electrical enclosures that will meet MSHA certification requirements according to Part 18, Title 30, of the Code of Federal Regulations, and fulfill their intended service underground. The guide covers only those aspects of design which affect enclosure strength, ruggedness, endurance and flame path, i. e., the enclosure ability to properly contain an internal explosion. Internal static and explosion pressures, external impact and thermal heating load are treated as well as the proper selection of materials and welding procedures.

Jan 1, 1985

By E. R. Rodriguez

Improved practice resulting from recent changes in the method of supplying compressed air and in pneumatic drilling equipment used in secondary drilling and in development work at the Morenci mine of the Phelps Dodge Corp., has resulted in improved safety conditions, as well as in a reduced cost per foot of drilling. A large stationary compressor installed outside the mining area and the compressed-air pipelines in the mine were replaced by portable compressor units. A self-propelled, self-contained drilling unit was obtained for drilling large footages where short moves were involved. Large wagon-drill units were replaced by faster and lighter drill machines and conventional bits by carbide insert bits. The safe practices employed in air drilling and in the related blasting and scaling operations have contributed to an excellent safety record at this mine. The complete sets of instructions listed in the company codes of safe practice aid materially in training employees.

Jan 1, 1956

A revolutionary development in blasting materials has occurred in recent years. Ammonium nitrate, sensitized by the addition of a small percentage of No. (class) 2 diesel fuel or other suitable petroleum product, has been adopted as a low-cost, efficient blasting agent2 in a wide variety of mining, quarrying, and heavy construction operations. Moreover, the ready availability of the component supplies throughout the Nation, together with the ease of formulating them into effective blasting agents, has made it possible for the blaster himself to prepare the mixes at the site of use. Recently, most established explosives manufacturers have begun supplying premixed AN-FO (ammonium nitrate-fuel oil) or a comparable product to various mining operations. However, many individuals and small business establishments are marketing premixed products prepared in facilities that are often poorly constructed and poorly located. Although these blasting agents have partly or wholly displaced explosives such as dynamites in many applications, there are some blasting operations in which the fuel-sensitized ammonium nitrate agents do not appear to be well adapted. As long as the hazards they present are clearly understood and respected, ammonium nitrate-based blasting agents have important safety characteristics when prepared under competent factory control or field-mixed under equivalent close control. This publication attempts to summarize the knowledge of those hazards and to incorporate practical ways to cope with them.

Jan 1, 1963

By Irving Hartmann

The Bureau of Minas has been charged by the Congress with the responsibility for administrating the provisions of the Federal Coal-Mine Safety Act. One of the important duties of bureau inspectors under this act is to determine whether proper measures are taken to prevent mine explosions, which in moat miner includes Judea adequate rock dusting The investigation made after the explosion in Orient No. 2 mine, December 21, 1951, showed that much information is lacking on the adequacy of current rock-dusting and duet-sampling practices in the United States. To obtain such information, an intensive sampling survey was conducted by the Bureau in an Indiana coal mine. This paper summarizes the more Important findings from this survey, describes special samplings at several Pennsylvania coal miners, and discusses related studies in the Bureau's Experimental coal mine.

Jan 1, 1954

By R. S. Dean

In the early days, most smelters were erected in nonarable land and at some distance from settled communities. The movement of population, which resulted in many instances from employment at the smelters, has brought to most smelterman in the United States the problem of preventing damage to plant and animal life in the territory adjacent to the smelters by sulphur dioxide gas (S02). This problem has been met, broadly, in two ways: (1) By diluting and removing the S02 by means of air currents and (2) by converting the S02 to a liquid or solid compound of sulphur and disposing of the compound.

Jan 1, 1937

By R. S. Dean

In the early days, most smelters were erected in nonarable land and at some distance from settled communities. The movement of population, which resulted in many instances from employment at the smelters, has brought to most smelterman in the United States the problem of preventing damage to plant and animal life in the territory adjacent to the smelters by sulphur dioxide gas (S02). This problem has been met, broadly, in two ways: (1) By diluting and removing the S02 by means of air currents and (2) by converting the S02 to a liquid or solid compound of sulphur and disposing of the compound.

Jan 1, 1937

By James A. Browning

Following an unsuccessful attempt earlier in the program to develop and market a drill channelling machine, we have designed and tested a new continuous channelling method which reduces operating sound levels to below 100 db. This new method relies on a small diameter oxygen-enriched burner to produce narrow channels. Sound intensities are reduced substantially compared to conventional channel widths. They are further reduced by a water spray directed immediately above the flame. Baffles placed along the top of the channel will reduce sound levels to below 90 db. Cutting rates are greater than those of existing channelling burners with costs per unit of channel area substantially reduced for those cases where oxygen costs are reasonable.

Jan 1, 1981

By D. E. Wolfson

As a part of its overall program of coal carbonization, the Bureau of Mines is studying the coking properties of coals that may be used for metallurgical purposes. The objectives of this study were given in detail in a previous report.2/ The inherent suitability of coal for metallurgical use depends primarily on (1) chemical composition, (2) preparation characteristics, and (3) carbonization behavior. The first two factors, as well as the available reserves, are considered in selecting coals for carbonization tests.

Jan 1, 1957

By P. B. Lorenz

Wettability measurements and laboratory waterflood tests were compared under a wide variety of conditions. Experiments were conducted with synthetic and natural crude oils, treated and untreated outcrop and oilfield sandstone cores, and synthetic brines with and without caustic, detergent, or phosphate additives. Measurements were made on equilibrated and unequilibrated systems at 77° and 150° F. Wettability was evaluated by the Bureau of Mines method from capillary pressure curves determined with a centrifuge. The waterflood data were fitted by empirical curves; the parameters of the curves characterize primary and subordinate production and also give the ultimate oil recovery. Results showed that wettability measurements at 77° F were useful predictors of recovery efficiency in waterflood tests run at both temperatures. Oil recovery in the early stages of waterflooding increased with increasing water wettability; however, the ultimate recovery was highest at a slightly oil-wet condition. The oil displaced at highest speed in the centrifuge was correlated with ultimate recovery in waterflood tests. Chemical additives to the brine sometimes lowered wettability and also sometimes improved waterflood recovery, but wettability and recovery were not correlated with additives present. The effect of additives on recovery in waterflooding was best seen in water-oil ratio curves.

Jan 1, 1974

By George F. Dana

Oil yields, lithology, and stratigraphy have been evaluated for 15 cored wells and two sampled wells representing 10 square miles of the Tipton Member of the Green River Formation near Green River, Wyo. The area evaluated is being used by the Bureau of Mines for experimental production of oil from the oil shales in place. Lithology and oil yields were correlated to produce a stratigraphy diagram for the in situ study area, permitting precise designation of comparable sections. Because of lateral uniformity of oil shale, oil yields from eight cores and two sets of drill-cutting samples within a quarter section show the range of variation in average oil yield arising from experimental error. Variation in average oil yields from the seven cores representing the 10-square-mile study area lies within the expected experimental error. No difference in oil-shale richness across the study area is indicated. Average oil yields for three Tipton sections in the study area were deter-mined as follows: (1) The entire Tipton Member oil shale (about 145 feet thick), 13.3 gallons per ton; (2) the 40-foot upper rich zone, 21.0 gallons per ton; and (3) the 21-foot zone in which the Laramie Energy Research Center is conducting in situ experiments, 22.4 gallons per ton. One acre of the 21-foot experimental section represents 34,300 barrels of oil in place, and 1 acre of the Tipton's 40-foot rich upper layer represents 62,000 barrels.

Jan 1, 1972

By John O. Atkins

[Experiments were conducted by the Bureau of Mines on five types of simuated lunar rock (dacite, tholeiitic basalt, vesicular basalt, pumice, and uluth Gabbro) to study the effects of various simulated lunar environments n their strength and deformational properties. Specimens were tested in an ltrahigh vacuum (UHV) system at pressures ranging from atmospheric down to 0-11 torr and at temperatures of -130°, 20°, and 135° C. All tests were onducted with a servocontrolled testing machine. Rock specimens tested at 0° C in UHV exhibited significantly higher compressive strength and Young's odulus than those tested at 20° C in atmospheric pressure. The magnitudes f increase are related to the porosities and permeabilities of the rock pecimens; high porosity and permeability allow better outgassing and thus nprove surface cleanliness in UHV. The compressive strength generally ncreases but Young's modulus decreases as test environments change from 20° C i UHV to 135° C in UHV. No significant difference was observed in the iysical properties measured at 20° C in LTV and -130° C in UHV. Anisotropy i strength and Young's modulus exist both in UHV and at atmospheric condi¬'.ons with the same symmetry pattern. The orientations of the principal axes iy, however, change from the atmospheric to UHV condition. The results idicate that rock fragmentation in lunar environment will require more ergy than that at 20° C in atomospheric pressure.]

Jan 1, 1974

By L. C. IlsLey

The Burrell methane indicator developed by Col. G. A. Burrell in 1915 was modified during 1918 to the " insulated type " Burrell indicator . Though this instrument has been used in mines since its first introduction , it was not formally approved as safe and efficient for use in gaseous mines until March , 1922. The indicator is built by the Mine Safety Appliances Co. , Pittsburgh , Pa . Approval No. 800 has been assigned to this company covering the device in the form approved . The principle of the Burrell indicator is fairly well known . It works on the same principle as the Haldane apparatus - measuring by means of a graduated scale , the contraction resulting from burning the methane content of an air and gas sample . A given aniount of the mine atmosphere to be tested for methane is taken into the indicator . This sample is then thoroughly shaken with the water in the indicator for one minute . The methane in the sample is now burned for two minutes by a heated platinum coil , which is energized by a small storage battery containing two Edison cells connected in series . After the glower or coil has burned for two minutes , it is disconnected from the battery , and the indicator is again shaken for The amount of contraction observed by reading the height the water rises in the U- tube of the indicator , which is calibrated to register the percentage of gas in the sample . The indicator as approved by the Bureau of Mines is equipped with an Edison M- 8 mine- lamp battery , and with a glass and scale graduated from zerɔ tɔ four per cent methane . The approval of a corbination service that is , an attachment for giving illumination from the same battery from which the platinum glower is operated has been withheld pending the development of a battery with larger capacity . - Under laboratory operating conditions , a single glower was capable of making at least 20 determinations if proper precautions were observed with respect to the use of freshly charged batteries . A battery should be allowed to stand off charge several hours before using in an indicator , as the peak voltage of a freshly charged Edison cell is abnormally high and is likely to send enough current through the glower to melt the platinum wire . Fifty-seven satisfactory operations were obtained from a completely charged battery . The point where the voltage of the cell fell below 2.3 volts with the glower attached was taken as the lower limit of successful operation . A voltage less than 2.3 does not permit the lower to burn at a temperature that will completely burn the gas in the air , thus giving a false indication .

Jun 1, 1922

By D. S. Kingery

Efficient transportation is necessary to complement modern mechanized mining methods. The increasing trend toward high-capacity face loading equipment has demanded equally efficient haulage methods; this has been met by increasing mine-car sizes, using larger locomotives, and increasing haulage speeds, all requiring properly installed and maintained haulage roads specifically designed for this type of traffic. The recommendations and specifications included in this circular were made to point out salient factors important to the proper construction and maintenance of track haulage roads and to serve as recommended standards for track installation and maintenance. GLOSSARY OF TERMS USED Haulageway. - The track, walkway, trolley wire, feeder lines signal end telephone lines, signals, telephones, support, and drainage of the entry referred to. Subgrede. - The base upon which the ballast is laid.

Jan 1, 1954

By Judith L. Bolis

The Bureau of Mines estimated the potential availability of iron ore from 129 domestic and foreign mines and deposits in 25 market economy countries. The availability of four products on a total and regional basis was determined from demonstrated resources of 75.3 billion It. From the resources evaluated there are a total of 18.6 billion It of sinter fines, 4.9 billion It of lump ore, 14.7 billion It of pellets, and 820 MMlt of pellet feed potentially available at a 15-pct DCFROR, f.o.b. port. On a regional basis, at or below a total cost of $0.26 per iron unit there are 1.7 billion It, 2.8 billion It, and 186 MMlt of sinter fines potentially available from Brazil, Australia, and Africa, respectively. There are 825 MMlt of lump ore from Brazil and 1.4 billion It from Australia potentially available at or below a total cost of $0.24 per iron unit. There are 2.1 billion It of pellets potentially available from the United States at or below a total cost of $0.80 per iron unit, while 442 MMlt are potentially available in Brazil at or below $0.38 per iron unit. South America has 208 MMlt of pellet feed potentially available at or below a total cost of $0.28 per iron unit. While the resources of iron ore are more than adequate to satisfy demand, the future of the iron ore industry is very dependent upon changes in the world economy, and on the domestic scene, changes in the domestic steel industry and steel imports.

Jan 1, 1987