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By Felicia F. Peng

The computer graphic routines and digital simulation program of coal cleaning circuits have been developed in the Mineral Processing Engineering Department, West Virginia University. The functions of the program include computing, tabulation and graphing of 1) washability characteristics of raw coals, 2) blending, 3) Tromp distribution curves for two washer types-- water only and dense medium, 4) predicting the functional relationship of yield and qualities of clean coal product in individual and overall coal cleaning circuits in coal preparation plant, and 5) determining the optimal clean coal yield based on the market and environmental specifications. Amdahl 470 V/7A digital computer, Tektronic 4025 graphic terminal and Tektronix 4663 digital plotter with Fortran IV are used to achieve the goals. The simulation with the aid of graphic routine program of coal cleaning circuits is a useful tool for coal preparation engineers in evaluating the feasibility of proposed flowsheets, in investigating the effect of a modification in a unit operation of an existing plant, in analyzing the off-line optimization, and in comparing the alternative circuit control strategies. The coal cleaning process simulation with graphic routine can contribute greatly to the decision making processes of preparation plant design.

Jan 1, 1983

By Cyril Wells, Robert F. Mehl

THE two earlier papers in this series1,2 presented data on the rate of diffusion of carbon and of manganese in gamma iron. Apart from their scientific interest, these [] data are needed chiefly in order to treat data on carburization, on the rate of formation of pearlite, and on the rate of austenizing in a quantitative way. 1,2,9,10 In the present investigation rates of diffusion of nickel in -?-Fe over wide temperature and concentration ranges have been determined, and the effects of carbon, of impurities, and of grain size on these rates have been studied. Claussen,3 using the data of Fry,4 has calculated the diffusion coefficient of nickel [ ] in -?-Fe as 9.2 X 10-11 sq. cm. per sec. at 1200T., but had no data from which to calculate the variation of D with concentration, temperature, and percentage of carbon. METHOD AND MATERIALS Method.-Nickel was diffused along the axis of a cylindrical specimen across a concentration gradient, concentration-penetration curves were determined and D values calculated from Grube or Matano solutions.5 Details of the method are given

Jan 1, 1941

By L. W. Kempf

THE thermal expansion characteristics of aluminum alloys have been examined by several investigators, among whom may be mentioned Shakespear,1 Schulz,2 Hidnert,3 Hidnert and Sweeney4 and McCullough.5 Shakespear compared the expansion of a series of aluminum alloys containing 14 per cent copper, with separate additions of about 1 per cent each of manganese, tin and zinc with that of pure copper. Schulz examined the expansion of aluminum and zinc and some aluminum-zinc alloys. Hidnert determined with a high degree of precision the expansion characteristics of pure aluminum, some aluminum-copper, aluminum-zinc, aluminum-silicon and some commercial alloys. Hidnert and Sweeney examined the expansion characteristics of aluminum-beryllium alloys. McCullough, by an interferometer method, determined the expansivity of some aluminum-copper, aluminum-magnesium, aluminum-iron, aluminum-nickel, aluminum-silicon and aluminum-manganese alloys. Incidental to an investigation carried out during the past six years and leading to the development and exploitation of an aluminum piston alloy of relatively low thermal expansivity, the expansion characteristics of a wide variety of alloys were examined. Some of the data which might be of general interest are gathered in this paper.

Jan 1, 1933

By John M. Logan, John Handin

Quasi-dynamic triaxial compression tests have been done for the first time at confining pressures to 7 kb. The intermediate strain-rate apparatus employs a gas loading cylinder which allows axial strain rates up to 102/sec on a sample 2 cm in diameter and 4 cm long. Samples can be deformed at confining pressures to 7 kb. Strain gages bonded to the loading piston and to the jacketed specimen allow internal measurements of load and sample strains respectively. Westerly granite has been deformed at confining pressures to 7 kb, room temperature, and axial strain rates of 10-2 to 1/sec. An increase of ultimate strength with confining pressure was found as expected. The ultimate strength was also found to vary directly with increasing strain rate; the rate of rise increases with confining pressure. Brittle deformation has dominated the sample behavior. Solenhofen limestone has been deformed at confining pressures to 3 kb, room temperature, and axial strain rates of 10- to 10/sec. The brittle-ductile transition was found to take place at about 1.5 kb confining pressure at a strain rate of 10/sec.

Jan 1, 1971

By Stanley Kesler

The first of two initial 650-mw units of the Paradise Steam Station, located on the banks of the Green River in the south-central portion of the western Kentucky coal basin, is scheduled for operation in late fall of 1962. This plant will be the eighth large-capacity, modern station built by TVA in a series starting with Johnsonville, operated first in 1951. During the subsequent ten years, unit sizes have increased from a capability of 125 mw to 650 mw at Paradise. This new unit will take its place in a power system that serves an area of about 80,000 sq miles with a present installed capacity of over 12,000 mw. Upon completion of the Paradise units and other additional hydro and steam units presently under construction, the system capacity will have reached over 15,000 mw. Projected load estimates indicate that this system will provide a margin of slightly under 10% of dependable capacity above peak demand at that time. One Paradise 650-mw unit at that time will represent approximately 4yc of the total system installed capacity.

Jan 10, 1962

By R. A. Foos

During the radium boom in the early part of the twentieth century, the basic chemistry of uranium was fairly well defined. Uranium production has progressed from the status of a radium by-product to a very important industry. With the ever increasing need for more efficient and cheaper methods of processing uranium ores, new techniques are being developed. Since uranium and vanadium often occur together in nature, the latter element will also be considered. As production rates, costs, and certain aspects of uranium chemistry are still classified by the Atomic Energy Commission, these will not be discussed. Domestic uranium deposits, in general, are composed of the minerals carnotite, which contains hexavalent uranium, and to a lesser extent, pitchblende and uraninite, which contain tetravalent uranium. Carnotite also usually contains vanadium. The uranium and vanadium contents of these ores vary considerably. The ores currently processed on the Colorado Plateau assay from 0.2 to 0.4 pct U and from trace amounts to 5.0 pct V. On the other hand, the phosphate rock deposits of the southeastern U. S., from which uranium is also recovered, contain only about 0.01 to 0.02 pct; processing of the

Sep 1, 1956

By Allan B. Tanner

The effects of radon in drillholes on gamma-ray logs have been described by L. S. Hilpert and C. M. Bunker1 Since these effects may cause drastic error in the evaluation of uranium deposits, it is useful to know the conditions under which significant amounts of radon tend to accumulate in drill- holes. In the studies described here, atmospheric conditions were found to dominate in the control of the behavior of radon in drillholes in the vicinity of a uranium orebody. The site of the investigation was in McKinley County, New Mexico, about 12 miles north of Grants. Drillholes of 4 ¼ -in. diam, on 25-ft and 100- ft centers, penetrate ore in dry rock at a depth of about 100 ft. A geologic log of the drillhole of primary interest is shown in Fig. 1. Gamma-ray logs revealed three zones of ore-grade mineralization in the Todilto limestone. A 6-ft zone, the lowest of the three, assayed 0.20 pct U3O8 by chemical analysis. The limestone ores in this area contain disseminated uraninite and some yellow and orange secondary minerals.

Jan 7, 1959

By L. O. Howard

MUCH work has been done recently on the lead-antimony system1 in connection with lead-rich alloys of commercial importance containing less than 20 per cent. antimony. Dean, Zickrick and Nix have called attention to the perpetuation in the literature of several erroneous data, such as a eutectic temperature of 228° C. at 12.5 per cent. antimony, instead of 247° at 13 per cent. The series is given as a classic example of a straight eutectiferous series in such late books as those of Heyn and Grossmann,2 Jeffries and Archer,3 Guillet and Portevin4 Pulsifer,5 Rosenhain,6 and Liddell,7 as well as the somewhat earlier works of Hofman (1918), Wang (1909) and Williams (1920). The work of Dean has definitely showed a solid solution of antimony in lead at about 2.5 per cent. antimony. While lecturing to a class in general metallurgy at the University of Idaho, the writer had the students prepare a series of lead-antimony alloys for the purpose of illustrating methods of thermal analysis. Proper proportions of powdered antimony (sold as C.P.) and test lead were mixed and melted in graphite crucibles under a reducing cover. Cooling

Jan 1, 1928

By W. N. Logan

THE petroleum industry in Indiana made no extraordinary progress during the year 1924. The surplus stock of crude, brought about by the production of 732,407,000 bbl. in the United States in 1923, as against a production of 557,531,000 bbl. in 1922, had its effect on prices though there were slight advances. These advances were more than offset by the continued high prices of labor and materials. TRENTON OIL DEVELOPMENT The principal development of the year occurred in the Hotmire pool of the Ridgeville district in northeastern Indiana. This pool lies partly in the southern part of Jay County and partly in the northern part of Randolph County. The oil is obtained from the upper horizon of the Trenton. During the past year, about 30 wells were drilled, 21 of which were productive. An attempt to extend the Hotmire pool to the northeast resulted in the discovery of a gas-producing area near the center of Pike township in Jay County; 10 wells have been drilled 4 of which produced oil. The Harvey Orr No. 1 produced 900,000 cu. ft. of gas per day.

Jan 3, 1925

On Feb. 16, 1948, the Board of Directors of AIME authorized the publishing of "Technical Notes" in METALS TECHNOLOGY. The purpose is to provide prompt publication of wry short items of the following general types: 1. Results of short investigations which do not warrant a paper. 2. The conclusions of extensive investigations of insufficient general interest to justify a regular paper. 3. Conclusions arising in the course of an investigation, which, because of interest to others in the field, the author wishes to present prior to completion of the investigation. 4. Pertinent factual comment (not mere argument) on the subject matter of previous "Notes." Such Notes will be subject to the approval of the Auxiliary and AIME Publications Committees, but can be handled more promptly than regular papers because they need not be referred to readers. The recommended maxi- mum length is 500 words; notes in excess of 1,000 words will not be considered for this type of publication. A graph or photograph may be included as part of the note when particularly illustrative. As with regular papers, contributions to the new section should be submitted to the Secretary of the AIME.

Jan 1, 1948

By T. A. Read, M. S. Wechsler, D. S. Lieberman

IN the formation of martensite in steel, it has been observed that the habit plane does not change continuously as the alloy content is varied. Instead, it appears that discrete habits correspond to certain ranges of composition. Greninger and Troiano' found that in low-, medium-, and high-carbon steels, the habits are approximately (1l1), (225), and (259), respectively.* The work of Mehl and Van Winkle2 indicated that the change from the (225) to the (259) habit is fundamentally a consequence of the lower transformation temperature rather than the higher carbon content. Also, Otte and Read3 observed that the habit plane orientation for a chrome-carbon steel scattered within a cone of semivertex angle of 5 deg, which was outside of the experimental error in the determination of the habit plane. These observations suggest the importance of investigating what factors in the crystallography of the formation of martensite account for the several types of habit and the inherent scatter in the precise orientation of the habit plane. A theoretical treatment of the austenite-martensite transformation has been given,4 which considers the total transformation distortion to be composed

Jan 1, 1961

By I. H. Warren, E. A. Devuyst

The selective dissolution of pyrolusite (MnO2) in presence of goethite (FeO•OH) in aqueous ammoniacal ammonium carbamate solution has been investigated: various reducing agents were studied, in particular sodium sulfite (Na2SO3,) and hydrazine hydrate (N2H4•H2O). Sodium sulfite was found to be an unsatisfactory reducing agent for both goethite and pyrolusite, for the leaching rate decreased steadily with time to an impractical level because of the limited solubility of the reactions products. Hydrazine hydrate was an effective reducing agent for pyrolusite even at low temperature, whereas goethite required much higher temperatures for any appreciable dissolution. A 1-hr leach at 35°C dissolved 90% of the pyrolusite but only 0.1% of the goethite. An activation energy of 17.0 Kcal per mole was found for the dissolution of pyrolusite with hydrazine. A reaction mechanism for the leaching of pyrolusite with hydrazine is proposed in which a reduction reaction on the surface of the mineral is the rate-determining step. The application of ammonium carbamate to the beneficiation of ilmenite is briefly described.

Jan 1, 1973

By Eldon C. Pattee

Variations of a very reliable geochemical field test for beryllium developed by Patten and Ward, have been adapted by the U.S. Bureau of Mines to facilitate rapid testing of reconnaissance samples and to aid in rapid examination of known occurrences. Although several qualitative tests for detecting beryllium have been described in the literature,1,2,3, the Patten-Ward4 morin geochemical field method has the advantages of being rapid and being quantitative for minute amounts of beryllium. In addition to the morin field method, Patten, in cooperation with Griffitts, have developed a contact- print method for determining beryllium in hand specimens.5 The semiquantitative method can be used for rapid screening of samples in exploration or reconnaissance work. The use of beads for fusing samples provides a more rapid test, but gives less accurate results than the method developed by Patten and Ward. The semiquantitative method, however, requires less equipment and combines three stock solutions into one reagent for easy application. Estimates of samples in the range from 3 to 1000 ppm varied from about 0.25 to 5 times the actual beryllium content.

Jan 5, 1965

By K. S. Seljesater

Since the development of dispersion-hardenable lead-antimony alloys' in the laboratories of the Western Electric Co., Inc., studies have been made of the effect of various third constituents on these alloys.2 This paper covers a study of the effect of small amounts of arsenic. This element is important since it occurs as an impurity in many commercial antimonial leads and the results obtained are particularly interesting as indicating a class of addition agents which exert a stabilizing effect on dispersion-hardened alloys. Experimental In order to study the effect of increasing amounts of arsenic, a series of alloys were made up containing 1 per cent. antimony, and arsenic varying from 0. to 0.10 per cent., the balance Doe Run lead (99.997 per cent. lead). The alloys were cast into bars 1 1/2 in. wide by 3/4 in. thick and cold-rolled to about 1/8 in- thickness. Three samples of each composition were annealed 1 hr. at 225" C. and quenched in water. One set was aged at room temperature, one at 50" C., and the third at 100" C., the

Jan 1, 1929

By K. S. Seljesater

Since the development of dispersion-hardenable lead-antimony alloys' in the laboratories of the Western Electric Co., Inc., studies have been made of the effect of various third constituents on these alloys.2 This paper covers a study of the effect of small amounts of arsenic. This element is important since it occurs as an impurity in many commercial antimonial leads and the results obtained are particularly interesting as indicating a class of addition agents which exert a stabilizing effect on dispersion-hardened alloys. Experimental In order to study the effect of increasing amounts of arsenic, a series of alloys were made up containing 1 per cent. antimony, and arsenic varying from 0. to 0.10 per cent., the balance Doe Run lead (99.997 per cent. lead). The alloys were cast into bars 1 1/2 in. wide by 3/4 in. thick and cold-rolled to about 1/8 in- thickness. Three samples of each composition were annealed 1 hr. at 225" C. and quenched in water. One set was aged at room temperature, one at 50" C., and the third at 100" C., the

Jan 1, 1929

By Dilip K. Paul, Charles H. Jacoby

The economic importance of salt domes has been recognized throughout the world, primarily because of oil and gas accumulations on their flanks, and to a lesser degree, for the value of their salt and potash. Recently they have become of value as hosts for cavities used to store hydrocarbons. In the near future we believe that their main value will be a source of geothermal energy. Although tremendous effort has been expended on the understanding of the geology and physical characteristics of the strata intruded by salt domes, relatively little energy has been exerted in the comprehension of the salt dome itself. Salt domes have long been recognized as a geological heat anomaly. With respect to other sedimentary rocks, salt is a good conductor of heat. Expressing values in 10-3cgs units, sedimentary rocks vary from 1.0 to 8.0; metamorphic rocks from 5.2 to 8.4 and igneous rocks from 3.1 to 9.8. Rock salt in its pure form has a thermal conductivity of 17. Thus a salt dome can be expected to act as a conduit bringing heat vertically from deep within the earth's crust.

Jan 5, 1974

By W. H. Bassett, J. C. Bradley

In their paper on the directional properties in cold-rolled and annealed commercial bronze,' Phillips and Samans suggest that cupronickel, under distinctly different treatments, shows both "45" ears" and "90" ears. Fig. I shows the ears on some cupronickel cups made some 17 years ago for bullet jackets for small arms ammunition. In this case the material heated to 425° C. had "45" ears, while that annealed at 950°C. showed long "90" ears" when drawn with the same tools. The method of cupping, the shape of cupping tools, etc., were found to have very little influence on the earing tendency, but the deeper the cup was drawn, the higher the ears would be. Method of Manufacture Cupronickel cast bars were 1 in. thick. Ordinarily, they were rolled with numerous passes to a thickness of 0.4 to 0.2 in., according to conditions. They were then given a single intermediate anneal, and rolled to finish thickness, frequently 0.032 in. After a last anneal the material was cupped with a "cut and draw" operation. Progress of this is indicated in Fig. 2, illustrating five different stages at which the drawing

Jan 1, 1933

Carlisle: Jim Knapp, has been the good friend of hundreds-maybe thousands-of mining men in these western states in the last 40 or 50 years. Jim is going to talk about many of the mining camps of Nevada, where he has done plenty in the mining field during the last 50 years. Jim, for a starter, how did you happen to go to Nevada? Knapp: In the summer of 1902, two years after the discovery at Tonopah, the professor of mining at Stanford sent out myself and another student by the name of Joe Miller to make a report on the camp. We left San Francisco at 8 p.m., got to Reno the next morning, then took the train to Sodaville, arriving about 4:30 in the afternoon. The first man I met when I arrived at the Tonopah station was Tasker Oddie, a gentleman who later became the Govenor of the State and then a United States Senator. Before we got away from the stage station I also met S. H. Brady, the first mining engineer to put out his shingle in Tonopah. He afterwards became general manager of the West End Mining Co.

Jan 3, 1965

By W. E. Foreman, James A. Redding

INTRODUCTION Screening is a mechanical process that separates particles by size. Modern coal preparation is made possible by efficient sizing. Sizing of coal is defined in terms of the opening through which an individual particle will or will not pass, or as two openings, the larger of which passes the particle and the smaller of which retains the particle. Screening accomplishes sizing by passing coal of a wide range of sizes through a series of screens, each of a decreasing size. The individual screen discharges are then directed into different screen products for subsequent sale or processing. Screening in modern preparation plants is done for the following reasons: 1 ) Removal of fine coal before a size reduction step. 2) Size separation of the coal into a coarse and fine fraction for sized products or processing in coarse and fine coal circuits. 3) Recovery of heavy media from heavy media coal cleaning circuits. 4) Dewatering. 5) Rock and trash removal by handpicking on a screen. Fig. 8-1 is a generalized flowsheet of a plant showing the use of screens in the coal preparation process. Table 8-1 shows the vibrating screen equipment utilized in Fig. 8-1

Jan 1, 1979

By Charles Catlett

Much has been done of late years to facilitate preliminary stratigraphical investigations, and for examination at considerable depths and in a certain character of material the diamonddrill, in its general forms, certainly stands pre-eminent among the tools for such work. But there are large classes of deposits —indeed, I may say the larger proportion in which ordinary. prospecting is done—which lie near the surface and are interbedded with soft and fine material. The method usually employed for prospecting these is by means of small shafts. These are sunk with considerable slowness and at considerable expense, depending largely upon the character of the material encountered, and are greatly interfered with by water. In this region the smallest are 3 by 4 feet, but they are usually considerably larger. Having had occasion during the past year to do a large amount of prospecting work, I have found the use of a hand-auger and drill of immense value in this respect, and in my practice it has largely superseded, and always preceded, the other forms of investigation. I believe that the information desired mas

Jan 1, 1898