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By Percy Gillie

THE Tralee preparation plant, owned and operated by the Semet-Solvay division of Allied Chemical and Dye Corp., is located on the Virginian rail- way, near Mullens, Wyoming County, W. Va., and the mine, which is in the Winding Gulf district, produces coal exclusively from Pocahontas No. 3 seam. The property, comprising 4900 acres, is leased from the Pocahontas Land Corp. Prior to 1930 four separate mines were operated in this tract, some having been started about 1916.

Jan 11, 1953

By Wayne D. Gould, Terry O. Arney

The Pinto Valley digital control system is a supervisory system interfaced with a conventional analog control system. The design criteria, the hardware selection, and the startup of the system in the Pinto Valley concentrator are reported in depth. Examples of data collection application, as well as the present and immediate future implementation of control strategies, are discussed. This paper is a description of the digital data acquisition and control system that is installed at Cities Service's Pinto Valley concentrator.

Jan 1, 1978

By Kwang K. Koh, Nicholas C. Nahas, Richard C. Neavel

Sodium, a relatively abundant element in Illinois coal, is reported to cause fouling of utility boiler heat exchange surfaces. Distilled water extraction of 22 Illinois coal samples resulted in average removal of more than 50% of their included sodium. Chlorine was the dominant anion. Extraction rate conformed to Fick's law of diffusion. Extraction with hot water increased both the rate and maximum amount removed. A commercial-scale countercurrent staged process can be envisioned as technically feasible.

Jan 1, 1978

By C. Hanford Henderson

The belt of copper-bearing rocks of the South Mountain has attracted Attention principally iii the townships of Hamilton Ban and Liberty in Adams County, Pennsylvania, and in the southeastern portion of Franklin County. As the developments, thus far, have been almost exclusively limited to that area, the examination here described extended only within those boundaries. The region, being one of considerable interest geologically, has been the subject of careful study and description, both on the part

Jan 1, 1884

By Joseph L. Mehaffey

A variety of chemicals offered by Armak were evaluated as dewatering aids for aqueous slurries of silica sand, sparsand and feldspar; an established commercial dewatering aid was used as a control. A number of Armak’s potential dewatering aids yielded lower moisture retention values than did the commercial product on all of the mineral samples. In addition to the chemical dewatering evaluations, some of the mechanisms involved in the removal of water from these mineral samples were examined.

Jan 1, 1984

By J. H. McCarthy, J. M. Botbol, R. B. McCammon, G. H. Gott

Four areas have been identified as favorable drill site locations for determining whether a suspected porphyry copper deposit exists in Rowe Canyon, NV. Favorability is bated on the similarity to a deposit model constructed from geochemical data for the porphyry copper deposit near Ely. Favorability is defined as the coincident number of positive anomalies for zinc, silver, aresenic, antimony, and iron. The favorable areas coincide with an observed magnetic high and areas in proximity to major faults.

Jan 1, 1983

By Robert M. Jimeson, James M. Grout

The competitive market potential for solvent-refined coal is estimated and the market advantages are enumerated. Markets are possible in combustion, railroad locomotion, and carbon electrodes. The combustion characteristics are consistent with expected air pollution restrictions on the emission of sulfur and particulate matter. A market potential of sufficient size exists to support the initiation of solvent refining in the United States. The market analysis should help fuel producers determine the advisability of their undertaking solvent refining of coal.

Jan 1, 1972

By John A. Church

The operations of the Tombstone Mill and Mining Company, in Arizona, have been extensive and interesting; and I will eudeavor to describe what is novel in their work, without attempting to go over the well-known facts of silver milling, concentration and smelting which are the general branches of their business. Their mines are at Tombstone, and their mills at Charleston, ten miles distant. The ore has been mined only above water-level, and at first was

Jan 1, 1887

By H. C. Juvkam-Wold

The aquifer depressurization system uses a number of wells surrounding a mine shaft to reduce the aquifer pressure in the vicinity of the shaft. The effect of various parameters such as number of wells, wellbore diameter, time, and well location is discussed. It is concluded that, with a properly designed depressurization system, the aquifer pressure and the water inflow rate to the shaft may be reduced to less than 15% of their potential values in the absence of wells.

Jan 1, 1983

By Clemens Catesby Jones

One of the achievements of the present century has been the development of brick-making from the crude and humble handicraft of the individual to a potential industry employing machinery, requiring immense capital, and now demanding that scientific direction which will finally raise it to the importance and dignity of a modern industrial process. It is as yet in the first stages of progress in this direction. The constant obstacle to a fully developed process has been the treat-

Jan 1, 1901

By T. J. DeMull

More than 1.81 mt (2 million tons) of low grade ore have been heap leached at the Alligator Ridge mine. Since inception of leaching in 1980, several modifications have been made to ore agglomeration, heap construction, and leach operation practice. These modifications have improved the percolation rate of the ore and the rate of gold extraction from the ore. Changes made in each of these areas are described and the effects of the changes are discussed.

Jan 1, 1984

By Arcy A., D&apos Shock

This paper delineates the scope of the developments which have taken place in expanding the utilization of the soluble salt provinces. The location, geology, extractive technology, as well as the growth of uses are reviewed. An expanding recent growth has been in the use of solution cavities for storing hydrocarbons. The development of the technology to obtain and operate these storage cavities as well as the development of the methodology for solution mining of the soluble salts are discussed.

Jan 1, 1985

By Charles S. Barrett, Robert F. Mehl

The system cadmium-mercury has attracted much attention, chiefly because of its importance in the study of electrochemical standard cells. The constitutional diagram, as it is accepted today, is essentially that developed by Bijl l (Fig. 1), though there has been a great amount of work done on the system by other workers.2 A year ago the senior author published a paper on the crystal structure of the system, in which were described determinations of crystal structure

Jan 1, 1930

[TWEEDY, A. M., and VOGEL, FELIX A.: The Briquetting of Flue Dust in the United States by the Schumacher Process, XLVII, [viii], 338. TWEEDY, GEORGE A., and BEALS, ROGER L.: Cyanide-Plant and Practice at the Minas del Tajo, Rosan'o, Sinaha, Mez., XLI, [xl], 324. Twin Falls plant, Peninsular Power Co., LI, 298. Twins, deformation lies in manganese steel, LI, 882. 2,000-Ton Leaching Plant at Anaconda (LAIST and ALDRICH) (With Discussion), LV, [xxiii], 866.]

Jan 1, 1918

By H. A. Dierks

PENNSYLVANIA's anthracite region lies in the heart of the richest and most densely populated area of the U. S. Nearly 70 million people live within a radius of 500 miles, in which 130,000 manufacturing plants employ more than 8 million workers. The region comprises some 3000 sq miles and contains 484 sq miles of coal measures, which folding and erosion have divided into four separate and distinct fields, known as the Northern, Eastern Middle, Western Middle, and Southern.

Jan 10, 1957

By A. G. H. Andersen

A FEW years ago, while the writers worked on the constitution of ternary and quaternary alloys consisting mainly of iron, chromium and silicon1,2 some information on microstructures and hardness, not incor-porated in the published work, was obtained. It has not been possible to do any further work on the properties of the alloys. The information possessed is hereby presented for the interest it. may have in connection with the constitution of the alloys.

Jan 1, 1937

By F. W. Lee

A GREAT CURTAILMENT of field activities among the geophysicists occurred last year, especially in prospecting for the common metals. In gold, however, an "outstanding achievement . . . was made by the engineers of Consolidated Goldfields. Here the suboutcrop of the Main Reef Series was traced from Middelvlei through properties of the westward area, a distance of from 30 to 40 miles. Here Drs. Reineche and Krahman prospected with the aid of a sensitive magnetometer and established the singularities of the various beds which heretofore had not been sufficiently appreciated. Several underlying shale beds were used to determine this suboutcrop under the dolomite. This area promises to be the equivalent of one-half the size of the present gold fields and to rank in value with the Far East Rand." The present temperature compensated magnetometers permit accurate field observations to less than 5 gammas. Since magnetic anomalies may have their origin due to a change of elevation as well as to the outcropping of a bed of another magnetically different material, intimate geological knowledge is of great assistance in the interpretation of these measurements. To what extent magnetic measurements reflect the basement when the material is homogeneous, consisting primarily of red granite, was determined by members of the Bureau of Mines and described by Dr. J. H. Swartz. Because of the diverse causes of magnetic anomalies, some of which were discussed and correlated by Stratton and Joyce upon known conditions, magnetometer measurements are often difficult to interpret.

Jan 1, 1933

By Christie A. Callender, Harry M. Dahl

The Hobson uranium deposit is located in Karnes County, Texas, along the prominent south Texas uranium trend. The uranium mineralization occurs in the Deweesville Sandstone of the Whitsett Formation of the Eocene Jackson Group. The host rock is a friable, fine-grained, well-sorted, highly porous and permeable sandstone interpreted to be an ancient beach deposit. The sandstone contains significant volcanic constituents and ranges in composition from arkosic to tuffaceous. Locally, the host sandstone contains hard, dense opal cement. Bentonitic shales underlie and overlie the mineralized sandstone unit. Geometrically, the Hobson uranium-bearing zone resembles an elongated roll front type deposit. Chemical uranium values compared with gamma ray equivalent uranium values indicate that the uranium has been dissolved from the updip side and precipitated on the down- dip side of the roll front. Details of the uranium mineralization were studied using thin section microscopy, autoradiography, x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. The uranium mineralization occurs in the pores of the sandstone, as grain coatings and as replacement of sand-size and smaller grains. It is commonly associated with pyrite and other opaque minerals. Other favored hosts for uranium (other than pore openings) appear to be clay aggregates, altered rock and glass fragments, and carbonaceous plant debris. Aggregates of coffinite were identified by XRD and SEM/EDS analyses. Some uranium mineralization also appears to be dispersed and is postulated to be adsorbed on the clay and carbonaceous matter.

Jan 1, 1985

By Lyon F. Terry

SPEED-UP of production of crude oil and its products, accompanied by rising prices and the organization of the industry on a war basis, featured the economic aspects of petroleum in 1941. Early in the year American tankers were urgently requested by the British to replace losses and offset slower transit under convoy. Some forty American owned tankers were first assigned to Britain and an additional forty-odd ships were transferred during the summer. This threatened to reduce our transportation facilities from Gulf ports to the Eastern seaboard below requirements, especially should sinkings have increased and the British needed more ships. Co-ordinator Ickes began preparations for restricting gasoline consumption in the Eastern district and plans were formulated for the construction of an emergency trunk pipe line from Texas to New York and Philadelphia refining centers, and for a gigantic tanker-building program. Sales of new oil-heating units in the East practically ceased. The companies were urged to transport as much oil as possible by tank car and by October 140,000 barrels of oil per day were reaching the East Coast district by rail, sufficient to meet 8 per cent of total requirements. But British sinkings from July through October decreased 63 per cent compared with the four months ended June 30, Britain began the return of tankers, the construction plans were dropped, and the threatened shortage was thus averted.

Jan 1, 1942

By J. C. Bradley

THE relation of annealing temperature to conductivity of copper wire has been determined. Conductivity hard was 98.26 per cent. After a 10-min. heating at 200°C. it was 98.69. By annealing 10 min. at 300° C. a large increase, to 100.93, occurred. Maximum conductivity, 101.15, was attained after a 500° C. anneal; thereafter it decreased to 100.53 after a 950° C. anneal. If copper is gassed the decrease is much more than this. Materials and Methods The work was done on high grade electrolytic copper, 99.942 per cent. copper plus silver, silver 0.0008 per cent. It was hot-rolled to >/4 in., then cold drawn to 0.080 in. The wire was cut into 25 5-ft. lengths and numbered 1 to 25 as cut. Four samples were tested hard. The others were wound into 5-in. diameter coils. For the 100° C. heating a coil was put into water, the water brought to boiling, and the wire kept at this temperature for 10 min. For the higher temperatures the coils were placed in envelopes of sheet copper, a little water added, and the envelopes sealed by folding over the edges twice, and hammering them together. This kept the air out very well. The envelope and wire 'were brought to the desired temperature; this was maintained for 10 min., then the whole was water-quenched.

Jan 1, 1927