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By Gwendolyn D. Hood

The Bureau of Mines investigated techniques for dewatering slurries from talc-processing operations to improve water reclamation and pro-duce dewatered solids suitable for disposal. Various flocculating reagents were evaluated, and a nonionic polyacrylamide was found to be most effective in a specialized flocculation dewatering technique. The flocculation dewatering method was applied in laboratory batch tests and in continuous tests using a static screen, a belt-roller device, and a clarifier-thickener laboratory unit. In continuous tests using the unit, wastes of 3.5 pct solids were dewatered to 56.9 pct solids using 0.03 Ib of flocculant per ton of dry solids treated.

Jan 1, 1983

By Jerry J. Gray

The utilization of secondary titanium was determined in a study by the Bureau of Mines, and a 10-year statistical table showing supply and distribution patterns is presented in this report. Over the total 10-year period, estimated scrap consumption is larger than estimated scrap supply. Trends from the estimated data indicate that titanium is in short supply and probably will continue to be in the future. Because of higher processing costs for recycle scrap, scrap will tend to migrate to the steel and aluminum industries and to ferrotitanium production and exports. Nonrecoverable losses of titanium metal during processing was determined to be a potential area for research.

Jan 1, 1971

By D. J. Stoops, H. Kato, M. D. Carver

The effects of impurity elements silicon , aluminum, copper , nitrogen , and manganese , at 50 to 300 ppm, on properties of the zirconium alloy Zircaloy 2 were investigated . Variations in microstructure , mechanical properties , and corrosion behavior in some inorganic acid and salt solutions were observed with variations in level of impurity element . Corrodents were solutions of sulfuric acid , phosphoric acid , copper chloride , and iron chloride . Silicon was found to modify annealed microstructures by spheroidizing and dispersion of secondphase material throughout grains . Silicon or manganese improved ultimate and yield strength of the alloy without loss in ductility . All five elements affected corrosion rates of the alloy , the effect being generally different for each element .

Jan 1, 1964

By A. S. Swanson

The Babb fault vein in Crittenden and Livingston Counties, Ky. (fig. 1), is one of an extensive series of such veins in the Western Kentucky and Southern Illinois fluorspar district. First operated in 1904, the production to May 1, 1944, was estimated at 143,000 tons of fluorite ore. There are five mines (fig. 2) on the Babb fault zone - Guill ,Kentucky Babb, Delhi-Babb, Eagle-Babb and Howard-Barnes. The Bureau of Mines developed four of these properties by core drilling from July 9, 1943, to May 1, 1944. During that period a total of 8,177.8 feet of diamond drilling was completed in 28 holes.

Jan 1, 1950

By James V. Kelly

During the spring and summer of 1947, the Bureau of Mines conducted an investigation and core-drilling program in the vicinity of the Rodham mine, approximately 4 miles north of Shullsburg, Wis. This work was undertaken as a part of a general study of the zinc and lead-producing area of southwestern Wisconsin. Work in the Rodham-mine area was done to investigate further a mineralized area frilled in part by the Puritan Exploration Co., a Delaware corporation, with offices in Galena, Ill. Some significant lead-bearing samples were obtained, but no continuous ore body was disclosed as a result of the Bureau of Mines work.

Jan 1, 1949

By Harold E. Heide

The United States is the world's largest consumer of tin and depends entirely upon foreign imports for its major source of supply. Only a small quantity of tin is produced on the North America continent. The advent of the war in Europe in 1939?brought a threat to our foreign sources of supply, and the Congress took steps to forestall shortages of tin and other metals. By authority of the Strategic Minerals Act, passed by Congress in 1939, and subsequent legislation, the Bureau of' Mines ?and Geological Survey conducted investigations of domestic tin deposits. Most of the tin that has been produced in North America came from the Seward Peninsula, Alaska.

Jan 1, 1948

By Raymond B. Ladoo

Silica , or silicon dioxide , ( Si0, ) , occurs in a free state chiefly as quartz , but hydrous silica ( amorphous silica carrying a variable amount of combined water , 2 to 13 per cent ) , occurs as opal , flint , diatomaceous earth , tripoli and so on . Quartz is found in many forms , the most important of which are ; As vein quartz; quartzite ; sandstone ; silica sand and gravel ; as crystals or crystalline grains , masses or aggregates in igneous rocks such as granites , dicrites and pegmatites . Commercially silica is used in many ways , but ordinary uses of sand and gravel are so well known that they will not be considered here .

Jan 1, 1922

By Arcy R., D&apos George

The Bureau of Mines has developed, on a laboratory scale, a superior Eluex-type circuit for eluting and recovering uranium from ion exchange resins. The improved circuit differs from conventional Eluex practice in that a stage of uranium solvent extraction is coupled with each stage of resin elution rather than the elution and solvent extraction operations being conducted separately. The new system reduces the number of stages, retention time, and resin inventory in the elution circuit to one-fourth or one-fifth that in existing circuits. The system is applicable to both resin-in-pulp and moving-bed-type ion exchange uranium recovery circuits.

Jan 1, 1969

By Joseph Cervik

Gas occurs in coalbeds in an adsorbed and a free gas state, Adsorbed gas is stored in the micropore structure and its transport is governed by Fick's law. The free gas occurs in the. fracture system and flows according to Darcy's law. These two modes of mass transport are interdependent. Production decline curves of coal-gas wells are of the constant percentage decline type and, thus, show no indications of flow characteristics peculiar to coal-gas reservoirs. The effectiveness of surface boreholes as a degasification scheme depends upon both good fracture permeability and a high fracture density. Conventional methods of reservoir engineering analysis are not applicable to coalbeds.

Jan 1, 1969

By W. H. Kerns

The Simon & Coles manganese deposit in Sherman Valley, Bedford County, Pa., was investigated by the Bureau of Mines during the fall of 1942. Two churn-drill holes; 65 and 75 feet deep were bored, and 8 channel samples were taken. Manganese occurs at this property in the form of psilomelane and manganiferous iron as replacement of the red sandy shale of the Much Chunk-formation. Two cars of manganese ore had been shipped by the owners in 1940, of which one averaged 10.9 percent manganese and the other 21.3 percent manganese. One car of hand-sorted manganese ore that averaged-45 percent manganese was shipped in 1942.

Jan 1, 1948

The Bureau of Mines believes that all coal mines are potentially gassy; for the purpose of administration in the prevention of explosions and fires, the Bureau recommends: That any coal mine wherein methane or other combustible gas can be detected in amounts as much as 0.27 of 1 percent or more by frequent systematic searches shall be classified as a gassy mine. Permissible methane-indicating detectors such as are given in I.C. 7110 or subsequent lists of Bureau approved methane-indicating detectors, or conventional methods of sampling and analysis of required accuracy may be used. The concentration referred to in the decision is percent by volume.

Jan 1, 1941

By F. D. Osgood, H. M. Cooper, A. C. Fieldner

The analyses in the tables are arranged geographically with respect to county and towns, and are grouped as follows: l The proximate analysis--moisture, volatile matter, fixed car bon, and ash; 2 The ultimate analysis-carbon, hydrogen, nitrogen, oxygen, sulphur, and ash; 3 The calorific value of heat of combustion; 4 The softening temperature of ash, when such determinations were made. Ultimate analyses are given in three conditions-namely, (1) as received, (2) moisture free, and (3) moisture and ash free Proximate analyses and heating values are given generally in one condition -namely, as received, some are in two conditions, as received and moisture free.

Jan 1, 1928

To improve a miner's chances for survival in an emergency by providing an improved self-rescuer device that functions in a toxic or oxygen-deficient atmosphere. The Approach: Development of a compact, lightweight apparatus which produces oxygen by using the wearer's breath in a chemical reaction. How It Works: The device is designed to cause the user's breath, which contains water vapor and carbon dioxide, to react with potassium superoxide (K02) to produce oxygen in quantities sufficient to sustain the wearer for one hour. The system is a closed circuit and does not depend on "screening" of noxious gases. To use the device, the miner opens the top and

Jan 1, 1974

Background: The National Institute for Occupational Safety and Health (NIOSH) recently investigated ignition incidents resulting from drilling holes into sealed and filled plow frame sections. A farmer and farm worker were seriously burned in two separate incidents that occurred in the same county in New York under similar conditions. They had just penetrated sealed sections of their plow frames with electric drills when a roar of escaping gas at high pressure was heard, and the victims were thrown back by the gas jet and engulfed in flames. The flames were quickly extinguished ,but the victims suffered burns. NIOSH experts were asked to help find the cause of these hazardous incidents.

Jun 1, 1998

By Allen Q. Howard

An approximate solution to the electromagnetic boundary value problem consisting of a horizontal cylindrical conductor buried in a lossy half-space and excited by an arbitrarily oriented magnetic dipole is found using an iterative perturbation technique in a double Fourier transform space. This model is used to gain insight into the anomalous fields due to strong scatterers such as pipes or tracks which would be in close proximity to an EM mine rescue operation. The novel, three-dimensional aspect of the problem (i.e., the source) imposes the complexity that the current in the cylinder is not uniform. The field expressions are ideally suited to evaluation using FFT algorithm.

Jan 1, 1973

By Nicholas G. Theofilos

Ecuador's real gross domestic product (GDP) increased 6% in 1976 despite persistent shortages of electrical power and essential fuels, which caused factory slow-downs and shutdowns. Petroleum export earnings, which made up more than 50% of total export value in 19716, totaled $565 million, a 9% increase over those of 1975. A new 60,000-barrel-per-day oil refinery at Esmeraldas was scheduled to go on- stream in mid- 1 97 7, operating entirely on Ecuadorean crude. Corpración Estatal Petró1era Ecualtoriana (CEPE) started construction of a 600-kilometer network of product pipelines which was scheduled to be completed in 1977 to coincide with the completion of the refinery.

Jan 1, 1980

By M. M. Tilman

A series of alloys was laboratory prepared by adding up to 4 weight-percent cobalt to the basic composition of type AM 350 (AISI 633) stainless steel. Aging curves were established for each alloy at 750° F, 850° F, and 950° F for lengths of time up to 100 hours. A series of annealed steels containing as much as 1 weight-percent cobalt was cold-rolled 50 percent and aged for 3 hours at 850° F. No improvement in hardness due to cobalt was observed in the steels transformed by heat treatment. Slight improvements in hardness were observed in the steels transformed by cold working.

Jan 1, 1968

By J. C. Franklin

An experiment was conducted by the U.S. Bureau of Mines and the Canada Centre for Mineral and Energy Technology (CANMET) to measure the emanation rate of radon from cemented unclassified mill tailings in two dewatered stopes of a uranium mine at Elliot Lake, Ontario, Canada. The radon was monitored upstream and downstream and in both stopes to determine the concentration in the stopes and the amount exhausted from both stopes. The emanation rate was determined to be 0.55 pCi/cm2 sec-1 from the mill tailings, which is approximately 1,000 times higher than the average flux in the mine before backfilling.

Jan 1, 1982

By E. Aamland

Preparation of high-purity magnesium-yttrium alloys by electroreduction of Y2O3 dissolved in a YF3-LiF bath and the subsequent deposition of yttrium in a molten magnesium cathode was investigated in laboratory-scale apparatus. Parameters such as temperature, current density, and electrolyte density were studied. Electrolysis was conducted in a specially designed MgO diaphragm cell at temperatures ranging from 780° to 970° C. Alloys containing up to 55 weight-percent yttrium were prepared at cathode current efficiencies of 21 to 60 percent. Cell design and operation are described, and some of the limiting conditions pertaining to the method are discussed.

Jan 1, 1973

By Charles L. Kimbell

The series summarizing the prices of the major nonferrous metals on the stock exchanges of the United States and the United Kingdom has been continued this year in tables 23 and 24. Time constraints have prohibited preparation of other price information that has appeared in this study in previous years. Users are urged to consult the 1993 USBM publication Metal Prices in the United States through 1991, which gives an analysis of historical price series and trends, or the 1993 edition of Mineral Commodity Summaries for current U.S. prices on non fuel commodities, and to utilize U.S. Department of Energy sources for information on fuel material costs.

Jan 1, 1993