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By S. J. Gasior

Pilot plant studies showed the technical feasibility of fluidized-bed operation for producing hydrogen and synthesis gas by the steam-iron process. A mixture of iron and iron oxide from 20-to 100-mesh was partially reduced with a simulated producer gas and then oxidized with steam and/or carbon dioxide. Results of tests show the effects of pressure, temperature, bed height, gas-to-solids ratio, type of iron oxide, and composition of gas on the gas and solids conversions during reduction and oxidation. A baffled free-fall solids system was also found operable. The short residence time of about 5 seconds limited conversion of the solids.

Jan 1, 1961

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

By L. H. Banning

Recent dry-top electric smelting tests at the Northwest Electrodevelopment Experiment Station, Albany, Oreg., indicate that a high-titanium slag and a good grade of pig iron can be produced from alluvial Idaho ilmenite. A total of 120 tons of concentrates were smelted during this investigation, to yield an average of 0.5 ton of slag and 0.3 ton of pig iron per ton of ilmenite. Power consumption averaged 1,400 kv.-hr. per ton of ilmenite, at a feed rate of 400 to 500 pounds per hour, when operating at an electrical energy input of 290 to 370 kilowatts. The optimum operating voltage appeared to be 110 volts, phase-to-phase. Graphite electrode consumption averaged 15.6 pounds per ton of ilmenite smelted. Magnesite furnace refractory withstood the corrosive action of the hot metal and slag better than carbon refractory.

Jan 1, 1955

By C. C. Merrill

Studies were made to determine the amenability of yttrium to fused-salt electrorefining in a controlled atmosphere. Tests were conducted in a LiCl- YCl3 electrolyte system at 710° C. The major variables studied were the YCl3 content of the electrolyte, from l.7 to 13.4 mol percent, and the initial cathode current density, from 410 to 1,630 amperes per square foot. Vacuum distillation was employed to remove salt from the deposited metal. Metallic impurities, except for lithium, could be reduced to near or below their lower analytical limits, ranging from 10 ppm for Cu to 300 ppm for Ta; reduction of oxygen content, however, was accomplished only in metal produced from electrolytes with 5.4 mol percent YCl3 or less. Initial cathode current density had little effect on the purity of the product.

Jan 1, 1967

By David P. Conover

The U.S. Bureau of Mines (USBM) has developed a computer-assisted Ground Control Management System (GCMS) for near realtime evaluation of underground coal mine ground conditions. The GCMS combines existing mine-monitoring system and sensor technology with automated computer analysis techniques to enhance the acquisition, analysis, and display of geostructural data. The GCMS, which combines mine structure data with other information, such as geologic conditions and mine layout, has provided information on mining-induced stress transfer and pressure buildup associated with several ground control events. The GCMS collects and analyzes shield-leg pressure, ground pressure, and strata movement data to evaluate the structural behavior of an active Western U.S. Iongwall coal mine. Field data are transmitted over a dedicated phone line to the USBM Denver Research Center (DRC) mine monitoring laboratory, 240 km (150 miles) from the mine site. Real-time collection, processing, and analysis of mine structure and shield pressure information has proved to be an effective method for near-face ground conditions while mining progresses. The GCMS provides the mine operator with information to rapidly identify and manage potentially hazardous ground conditions while mining is in progress.

Jan 1, 1994

By M. R. Geer

Full-seam mining with continuous mining machines in dirty coal beds may increase loss of coal in the washery refuse. At one mine mentioned in this report the loss of salable coal was increased sixfold. Cleaning trials were made on three samples of jig refuse in a dense-medium pilot plant to demonstrate the application of this process to the recovery of coal from waste. These tests demonstrated that coal could be separated from impurity with the same degree of sharpness obtained in treating raw coal by dense medium. However, the recovery efficiency achieved in treating refuse averaged distinctly lower than that possible with raw coal because of the greater proportion of intermediate-density material in the feed and the lower yield of clean coal.

Jan 1, 1955

By P. M. Sullivan

This report describes a new application of electroamalgam metallurgy in recovering all the zinc as refined metal from galvanizers' sal skimmings. Pure zinc was recovered by electrolysis of skimmings leach liquors in amalgam cells. The following information was gained as a result of literature studies and subsequent laboratory investigations. 1. Reports in the literature indicate that pure zinc can be recovered from chloride solutions with the aid of amalgam cells. From Europe it was reported that amalgam cells could be used to recover pure zinc and chlorine from leach liquor obtained from pyrite cinders following a chloridizing roast.

Jan 1, 1956

By Robert F. Randolph

Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This two-part article reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Part II will describe research to reduce these accidents, including improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

Jun 1, 1997

By Robert F. Randolph

Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This two-part article reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Part II will describe research to reduce these accidents, including improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

Jan 1, 1997

By William E. Eckard

Production of oil from a narrow shoestring sand presents problems unique in the oil industry. Especially important, from both an engineering end an economic standpoint, are the limitations imposed upon well patterns and spacings by the shape of the field. This report concerns a study of the Paola shoestring, Miami and Franklin Counties, Kane., where well density of 0.85 acre per well was not uncommon to insure profitable primary recovery in a reasonable time. However, such a great number of wells increased the operator's investment and reduced his profit considerably. It was the purpose of this study to investigate various well patterns and spacings applicable to water-flooding a shoestring reservoir and the effect of these factors upon recovery of oil and the most profitable operation of the pool. The designer of well patterns for a shoestring sand should evaluate carefully the edges of the shoestring, even though they may be considered too thin to drill. These comparatively thin edges contain large quantities of recoverable oil; moreover they are resaturated with oil as the pool is water-flooded.

Jan 1, 1951

By Foster Fraas

The electrical conductivity of minerals increases with increase in temperature as a result of the thermal activation of the electrons. Some oxidizable minerals have a change in the stoichiometric proportions after heating in air, and the conductivity does not return to the original value after cooling. Similar changes occur in reducing atmospheres. Other minerals, such as carbonates and hydrates, are completely decomposed. Electrical resistivity measurements on single particles when compared to standard separation measurements show that minerals having resistivities above 1013 ohms respond as nonconductors. Those below 1011 respond as good conductors.

Jan 1, 1956

By J. W. Paul

This circular is one of a series of reports on coal mining methods and cost s which are being prepared by the U. S. Bureau of Mines for the purpose of making available to those interested in the industry a knowledge of the mining methods employed in mines where mechanical and hand loading is practiced and the cost data on the several operations pertaining to the removal of coal from the working faces and its transportation to the tipple for loading into railroad cars. The methods employed are influenced by the natural local conditions with respect to the thickness and character of the coal beds and the overlying strata, the means employed for roof support and its control, and the disadvantages incident to the development of mines in thin coal beds.

Jan 1, 1929

By D. E. Sullivan

The Minerals Availability Program of the Bureau of Mines conducts cost evaluations of current and potential mineral operations in the United States and foreign countries. The International Mining Cost Indexation System (IMCI) allows data of different time periods within a country to be updated to a common base year for analytical purposes. The IMCI comprises 12 factor cost indexes and an exchange rate series for 96 market economy countries, denominated in both local and U.S. currency. The IMCI for each country contains 12 time series indexes that measure the average annual rate of change in the cost of factor inputs to the mining industry within that country. Mining industry factor cost indexes include wages, plant and equipment, construction and mining materials, power and transportation, and other measures considered to comprise the majority of capital and operating costs. Cost data or proxies are collected in local currency. Index series within each country are constructed separately and indexed on a 1975 base year. The local currency index is converted to a U.S.-dollar-based currency index using an exchange ratio.

Jan 1, 1987

By Michael S. Miller

In 1986 and 1987, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the nine separate parcels that comprise the 4,330-acre South Warner Contiguous Wilderness Study Area in order to evaluate their identified mineral resources. The nine parcels are along the east side of the South Warner Wilderness. They are, from north to south, the Granger, Milk, Cottonwood, Owl, Hornback, Eagle, Emerson, Barber, and Van Riper parcels. The Wilderness Study Area is underlain by basaltic, andesitic, and rhyolitic volcanic rocks and by sand and gravel deposits. Low-grade metamorphism is widespread in the volcanic rocks, with quartz, zeolites, datolite, chlorite, and calcite locally abundant in veins and amygdules. The rocks have been displaced by the mountain-front Surprise Valley fault and by crosscutting high-angle faults.

Jan 1, 1988

By Charles A. Kumbe

"INTRODUCTION The Sullivan Mine was examined by Thomas L. Chapman, an engineer of the Bureau of Mines, in March 1943. Samples taken from the few mineralized exposures justified further investigation of the property. To determine whether extensive exploration of the property would be warranted, the Bureau did a small amount of trenching and underground work during April 1943, 3/ under Bureau project 1462.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its, primary objective the, more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratary project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurigical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests.The investigations of the and Metallurgical Branches of the Bureau, as reported in this paper, were supervised by J. Hedges, district engineer for Arizona, and S. R. Zimmerly, regional engineer for the Western Region, respectively."

Feb 1, 1947

Provide longwall operators with an alternative strategy for placement of gob gas ventholes to improve gas production.

Jan 1, 1995

By Leland A. Yerkes

Refining aluminum from crude aluminum alloys by the subhalide reaction was investigated to develop a method of producing aluminum by means other than electrolysis of its oxide. The best materials and design for the apparatus and also optimum operating conditions, including temperature, pressure, vapor flow rate, and composition of alloy charge were studied. In the subhalide process, aluminum-trihalide vapor reacts with aluminum in the alloy under high temperature and low pressure, forming volatile aluminum monohalide which reverts to aluminum metal and aluminum trihalide on cooling. The only halide used in this investigation was aluminum trichloride. The crude aluminum-silicon alloys used as the principal raw material contained from 21.9 to 36 percent aluminum, and significant quantities of iron and titanium. These alloys were produced by direct electric smelting of clays. Graphite tubing that was heated by an induction coil proved to be satisfactory material for the laboratory reactor chamber, Enclosed in an insulated glass or quartz pipe, the reactor was used in both vertical and horizontal positions with various baffle and tray arrangements for directing the trihalide vapor both over and through the alloy. Aluminum trichloride vapor was generated in the sublimer at one end of the glass pipe, passed into the reactor where contact was made with the crude alloy, and aluminum monochloride gas was formed. When the gaseous mixture of aluminum monochloride and unreacted tri-chloride passed out of the reactor and entered the condenser, the gases were cooled to 900° C. or less, causing the monochloride to disproportionate into aluminum and aluminum trichloride vapor. The aluminum was deposited on the condenser walls while the aluminum trichloride vapor was carried out of the condenser and into the opposite end of the glass pipe where it solidified on the cooled copper coils.

Jan 1, 1961

By Ray J. Holmquist

"INTRODUCTION At the request of Elmer Burch, of Taos, N. Mex., the Apache mica mine was examined by an engineer of the Bureau of Mines in October 1942. As the result of this examination, the Bureau of Mines proposed to extend an adit to the projection of the mica-bearing dike. The Federal Geological Survey then prepared a topographic and geologic map of the property. This information and consultations with members of the Survey 3/ assisted in determining the course and extent of the exploratory work. The author supervised the work, which was done from January to May 1944.Title to the property was in litigation during the period of the Bureau of Mines investigation. Conrad Johnson, of La Madera, N. Mex., was contesting the valley of Burch's claim location covering the Apache mine. Johnson was a prior claimant. A map made during mining operations prior to 1929, showing all mine workings, was in the possession of Johnson, but he would not produce it for inspection as long as his title to the property was in doubt. The course of the adit extension was therefore controlled by the best information and judgment otherwise obtainable."

Mar 1, 1947

By B. E. Blair

"This report presents the physical properties and related geological and petrographic data of some 84 rock types from operating mines, quarries, or blasting research test sites. These fundamental rock data were collected as a quantitative approach to underground mining problems, blasting research, or other related studies; however, the data are equally applicable to any problem wherein rock characteristics are important factors. Stress-strain curves are given where available, and the standardized procedure for determining elastic constants from static tension tests is described. Computed (laboratory) and measured (field) free-medium velocities are compared in those instances where such data are available. A chart is given showing both the optimum and minimum number of test specimens for the various core sizes employed in the Bureau of Mines standardized physical-property tests. Rock-type, geographical, and geological indexes are included to aid the reader in locating physical-property data in this and previously published Bureau of Mines physical-property reports.INTROD'OCTI ONThis report presents the physical properties of 84 rock types tested from 16 different projects (sections 37-52). Two previous physical-property reports 2-3 / (hereinafter referred to as parts I and II) presented data on 160 rock types from 36 different projects (part I, sections 1-25 and part II, sections 26-36).The physical-property data were originally obtained to supplement structural mining problems, seismic studies, or related investigations; however, they should be equally applicable in all fields of studies where the strength, hardness, or other properties of rock are important factors. The properties, determined from laboratory tests performed on diamond-drill core, include the following:"

Jun 1, 1955

By K. E. Stanfield

The oil yields of sections of Green River oil shale in Colorado, Utah, and Wyoming are presented as part of a continuing project to determine oil-shale reserves in the United States. Oil-yield logs, based upon analyses obtained from 1945 through 1952, are presented to show the thickness and richness of 202 sections of Green River oil shale. The logs are based on analyses of approximately 20,500 samples, representing 179,000 feet of shale, which were made by the Bureau of Mines, and upon analyses, representing approximately 26,000 feet of shale, which were made by other agencies. The samples consisted of cores from a Bureau of Mines coring program in U. S. Naval Oil-Shale Reserve 1, Garfield County, Colo., and cores, drill cuttings, and channel samples provided by other agencies, chiefly oil companies. Most of the samples of oil shale from Utah and Wyoming were derived from oil-well drilling operations. As a result, the oil-shale sections were widely scattered and were not extensive or reliable enough to be representative of the significant deposits of Green River oil shale in these States. The oil-shale sections for Colorado, however, were more comprehensive, and a number of the sections were used in a previous report as a basis for estimating oil-shale reserves in Colorado. The present report does not give estimates of oil-shale reserves but is limited to presentation of oil-shale analyses that may be used for future reserve estimates. Other sections of Green River oil shale are being analyzed, and the results will be published in subsequent reports.

Jan 1, 1954