Search Documents

By M. J. Stewart, F. Weinberg

PREVIOUS investigations into convective flow in molten metals have examined systems in which the length-to-height ratio of the enclosure is large, usually using long graphite boats.''2 In normal castings this ratio is generally small and it is not possible to extrapolate the results of previous work to casting configurations. The present investigation was undertaken to examine liquid flow in systems of low length to height ratio. The apparatus used for the experiments is shown in Fig. 1. The molten zone of tin is contained in an aluminum mold of inside dimensions 6.4 by 6.4 by 0.31 cm. A heating block containing a resistance coil is attached to one end of the mold and a cooling block is attached to the other end. These are used to produce a wide range of temperature differences across the mold. The mold is contained in a stainless steel tank which is heated from the outside by resistance heaters to give the required operating temperature during the experiment. Temperature measurements in the molten tin are made with an iron-constantan thermocouple PT equal to 5 atm. The phase diagram derived by us was the same as that found by Krivsky and Schuhmann, except for a similar discrepancy in one boundary line representing the gas composition in equilibrium with SO a. The vapor pressures of the pure components can be neglected at 1700°K, 1 atm and 2500°K, 5 atm. There-fore, in these cases PT is essentially the total pres-sure in the system. This is valid for all the diagrams presented by Krivsky and Schuhmann except for the one at 2500°K and 0.01 atm, where the vapor pressure of silicon is comparable to PT.6 This work was supported in part by the American Iron and Steel Institute. 'C. E. Wicks and F. E. Block: Thermodynamic Properties of 65 Elements, U S. Bur Mines, Bull. No. 605, 1963. R. P. Elliott: Constitution of Binary Alloys, 1st supplementary, McGraw-Hill Book Co., New York, 1965. 3W. A. Krivsky and R. Schuhmann, Jr.: Trans. TMS-AIME, 1961, vol. 221, pp. 898-904. 4M. F. Ancey-Moret, M. Olette, and F. D. Richardson: Mem. Sci. Rev. Met., 1964, vol. 61, pp. 169-76. 5J . F. Elliott and M. Gleiser: Thermochemistry for Steelmaking, vol. 1. Addison-Wesley, Reading, Mass. 1960. 6 J.Drowart, G. De Maria, and M. G. Ingraham: J. Chem. Phys., 1958, vol. 29, p. 1015. probe of 0.4 mm diam inserted into the open top of the mold. Radioactive sn113, in the form of a small sphere, was gently lowered into the molten tin at point A in Fig. 1 THERMOCOUPLE> WATER ARGON END HEATER QUENCH ARGON Fig. 1—Apparatus for detecting liquid flow. Point A indicates position the tracer was introduced.

Jan 1, 1970

By Donald W. Mitchell, John Nagy, Edwin M. Murphy

In 1957 research was initiated in the U.S. Bureau of Mines experimental coal mine near Pittsburgh, Pa., to study factors affecting foam generation and transport, to evaluate the effectiveness of high-expansion foam for controlling mine fires, and to develop techniques for applying the method under U.S. mining conditions. These investigations showed that high-expansion foam containing at least 0.2 oz of water per cu ft of foam is effective in controlling experimental underground fires burning coal, wood, and oil. Sometimes the fire was completely extinguished, but more often, it was brought under sufficient control to permit either a direct attack on the fire with a stream of water or loading of the hot material into cars. A progress report prepared in July 1958 summarized the initial achievements of the USBM experiments. Since then other phases of the foam-plug method for attacking fires have been studied in the laboratory and in the mine. Previous studies by British engineers of the foam-plug method for fighting mine fires indicated that high-expansion foam was effective in controlling experimental timber fires in an underground passageway. Their subsequent work pertained to the practical aspects of fighting large fires within a mining area with a foam-plug.

Jan 9, 1960

THE foundation established by the partners of the late Robert W. Hunt provides for both a medal and a prize. The latter has not been given before this year, and the first award is to C. H. Herty, Jr., for his several papers on the physical chemistry of the open-hearth process.. He is the son of the well known chemist of the same name. He was born at Athens, Ga., on Oct. G 1896, graduated from the University of North Carolina in 1918, and went into war service as foreman of U. S. Chemical Plant No. 4, at Saltsville, Va. In 1919 he went to Massachusetts Institute of Technology, where he was successively instructor, research assistant, and research associate in the School of Chemical En-gineering practice receiving his master's degree in 1921 and his Ph.D. in 1924. He continued his brilliant work on the physical chemistry of the open-hearth process, much of it being done in cooperation with the Bethlehem Steel Co. at its Lackawanna plant, and dealing with the elimination of sulfur. In 1926 he joined the staff of the U. S. Bureau of Mines, in charge of its ferrous metallur-gical work at Pittsburgh, and continues to be active in research work on the physical chemistry and metallurgy of the open-hearth process. His Institute publications are: Some Factors Affecting the Elimination of Sulfur in the Basic Open-hearth Process," "Chemical Equilibrium of Manganese, Carbon and Phosphorus in the Basic Open-hearth Process" and "Desulfurizing Action of Manganese and Iron," and he will present a paper on ?Effect of Temperature on the Solubility of Iron Oxide in Iron" at the annual meeting.

Jan 2, 1928

The New York Meeting this year will-be held from Monday, February 19 to Thursday, February 22. The Committee on Arrangements, the personnel of which is given elsewhere in this Bulletin, is making plans to duplicate the conspicuous success of last year's meeting in New York. The papers to be read at this meeting, it is believed, furnish material for interesting and profitable technical sessions and symposiums. The social features are being carefully planned since it is believed that these form an important part of such meetings; several functions are to be, given with the object of fostering the get-together, know-each-other-better spirit. Ladies are invited to attend this meeting and participate in the various affairs planned by the Ladies' Committee and by the Committee on Arrangements. This preliminary notice is given in order that members may make their plans now to be in Now York at the time of the meeting. Full details will be sent to the membership through the mails as soon as the program has been definitely fixed.

Jan 1, 1917

By Daniel T. O’Brian

Mineral exploration activities are benefiting from new interpretive techniques which have become economically practical with computers. Government agencies, educational institutions, and industry have each contributed research and development efforts for improving the mathematical analysis and graphical display of exploration data, resulting in operational aids not foreseeable a decade ago. Progress has been worldwide and is expanding rapidly. Books 1-10 are supplementing the periodic literature, at least one abstracting service is now active, 11 and an association has recently been formed to encourage and publicize advances in this field. 12 With the diversity of applications, only partial coverage of the subject can be made at any single symposium. Four of the six papers in this section report on the current state-of-the-art in selected areas of interest: graphics, time-sharing, mathematics, and economic analysis. The remaining two papers are descriptions of advanced statistical techniques for gaining additional information during exploration, and illustrate methods which will become more commonly applied in the future. "Computer Graphics: A New Tool for Exploration and Mining" describes the use of a computer and accessory equipment as an information retrieval device, graphically merging and displaying pertinent information for visual inspection and interpretation. This is a rapid means of studying information which has been pre-stored in a form accessible to the computer. Time-sharing is a means of achieving a comparable rapid response when calculations are being performed. The paper, "Some Applications of Time-Sharing in Mining Geophysics," describes the experience of one company using a time-sharing facility for geophysical computations. Another paper on this subject, stressing mining applications, has recently been published. 13

Jan 1, 1969

By Albert A. Mathews

OUTCROPS of gypsum rock near the present site of the city of Gland Rapids, Mich., were known to fur traders early in the nineteenth century. However, the deposits seemed without value and were not worked for some time. So far as cat1 be learned, Michigan gyp- sum was first used by a plasterer who settled in Grand Rapids in 1834 as a member of its fourteenth white family. In building a house for one of the early traders, be used some otnamental stucco mouldings manufactured from the local gypsum deposits for decorations in the gables and around some circular windows. The gypsum was broken out with a hammer, ground in an Indian corn mill, and burlled in a caulclron kettle,. After two attempts, the ornaments were successfully set, and remained on the house until it was destroyed by fire in 1850.

Jan 1, 1936

By Helen L. Cannon

BOTANICAL methods of prospecting for metalliferous ores are based on the premise that deposits at depth may be reflected chemically in surface vegetation. For the past several years, on behalf of the Atomic Energy Commission, the U. S. Geological Survey has investigated on the Colorado Plateau the application of botanical methods to uranium prospecting. Results suggest that orebodies may be found under a considerable cover of barren sandstone through the absorption of uranium and associated trace elements by plants growing at the ground surface. Plant physiologists have demonstrated that uranium is a necessary nutrient for plant growth and therefore is present in all plants.' The amount present is small but measurable. The absorption of uranium by plants growing over ore deposits forms the basis, therefore, for a method of prospecting by plant analysis.

Jan 2, 1954

By Herbert Kilburn Scott

The information in this paper was collected by the author during a five years' residence in the State of Minas Geraes. Outside the State itself, very little is known of the gold-field. Such accounts as have been published are antiquated and contained in publications mostly out of print. The increased attention now attracted to the natural resources of Brazil, and the probability that American capital will be, in the near future, largely invested there, will make an up-to-date account specially useful at this time. I. Historical and General. Soon after the Jesuits founded what is to-day the city of S?o Paulo, gold was discovered in the streams of the neighborhood; and this incited the natives, known as paulistas, to look for it farther afield. After many expeditions into the interior, gold was found in quantity in placer-deposits in the vicinity of Ouro Preto, in 1699, by a prospecting party headed by Antonio Dias. The name of Ouro Preto (black gold) was given because of the superficial dark coating of the gold, and the inhabitants of the district were known as mineiros (miners). Later on, the placers of Cuiaba, in the State of Matto Grosso, were discovered in 1718, and those of the State of Goyaz in 1724. All this territory was at the time a private colony, but on account of its increasing importance it was taken over by the Crown, and in 1739 a royal governor was appointed, with his nominal capital in S?o Paulo, though for a number of years the real capital was Ouro Preto. In 1711 Ouro Preto was raised to the rank of a city, with the name of Villa Rica de Ouro Preto (" rich city of black gold"); and in 1720, by reason of administrative difficulties, Minas Geraes was constituted a separate colony from S?o Paulo, with Villa Rica as its capital. The site of this city

Jan 1, 1903

By C. H. Jr. Herty

THE removal of sulfur from steel has been studied by many investigators, but the quantitative relationships between the factors involved have not been determined. This is undoubtedly due to the number of variables encountered in practice, an attempt to study any one reaction or relation being affected by other reactions the relative importance of which cannot be estimated. The factors that affect the extent of removal of sulfur in the basic open-hearth process are generally considered to be: 1. Basicity of the slag: (a) Iron oxides in the slag; (b) carbon in the metal, or carbide in the slag; (c) temperature. These factors affect the reactions: FeS + CaO = CaS + FeO FeS + CaO + C = CaS + CO + Fe. 2. Amount of sulfur in the gas. 3. Amount of manganese in the metal. The factors which affect the rate of removal of sulfur include, in addition to these 4. Fluidity of the slag: (a) Normal changes in fluidity with temperature; (b) changes in fluidity because of the addition of special reagents such as fluorspar. 5. Agitation of the bath.

Jan 3, 1925

By Henry Fernald

THE accounting system or bookkeeping methods of any company are principally the concern of that company and of those who are in control of its affairs. Its published financial report is, however, primarily intended for those who are not already fully informed regarding its operations and finances. Whatever may be the advantages of standardization of accounting and bookkeeping methods, it must be admitted that a company has a certain right to handle its accounts and keep its books and records in whatever manner may seem to it best adapted to its affairs, even though such methods may differ materially from those generally adopted by others. In its financial reports it should not, however, either ask or expect that the statements it makes or the terms which it uses will be given in its case a meaning and interpretation different from that which they are ordinarily considered to have in similar reports and statements of other companies. The particular form and arrangement of such reports is a matter concerning which there may be much difference of opinion. It is of little importance whether current assets come first or last in the Balance Sheet, but it is important that there should not be included under this designation any items which are not properly current assets within the generally accepted meaning of that term. The extent to which stockholders or others interested are to be made acquainted with the full details of a company's business is a question which the proper authorities must in each case decide. It should, however, be recognized that there are certain facts regarding a mining com-pany which must be set forth in a financial statement if it is fully to cover the conditions and affairs of the company. For example, a financial, statement which does not include or is not accompanied by a statement, of the ore reserves of the company does not fully set forth its financial condition. This is true whether the absence of such a statement of ore reserves is because it is not desired to make public the figures or whether it is because the ore reserves themselves are not definitely known, or accurately measured.

Jan 1, 1928

By A. R. Powell

Four, general methods have been used in the study of the decomposition of coal. The first has been directed toward the processes of coal formation, the second has been by means of microscopic studies, the third from the data of destructive distillation, and the fourth has made use of various solvents. Applying these methods to the sulfur of coal, it has been found that the organic sulfur of plant and animal life enters into the formation of coal and remains in organic combination in the final product. The inorganic sulfur is almost entirely combined as iron pyrites and marcasite. The infiltration of hydrogen-sulfide waters is doubtless a large factor in these combinations. Sulfates are found in very small quantities except where free oxygen has entered the coal strata. The mechanical mixing of detritus with the early coal material is another source of sulfur. In this case the sulfur is distributed in microscopic particles throughout the mass. In destructive distillation, a part off the sulfur comes off as hydrogen sulfide and various thiophen compounds, but this furnishes little information as to the nature of the sulfur compounds in the coal itself. The use of solvents has given valuable data concerning the sulfur compounds in coal. Fremy1 and later E. Guignet2 noted the action of alkaline solutions on coal after treatment with nitric acid and Anderson and Roberts3 showed' the presence of large quantities of organic' sulfur in the extract so obtained. In a study of the phenol extract of coal, Parr and Hadley4 found organic sulfur in the soluble organic material. These investigations proved the presence of organic sulfur in coal in addition to the inorganic forms, such as iron pyrites and sulfates. T. M. Drown5

Jan 9, 1919

BEFORE me is a colored mining-claim map of the productive portion of the Robinson Mining district-sometimes called the Ruth-Kimberly area-that lies a few miles west of Ely, Nevada. It covers an area of 20 sq mi and at the end of 1954 had produced just under 2,000,000 tons of copper and about 2,000,000 oz of gold as a by-product. The three principal colors on the map and the meaning of each are: Red -Property of the Nevada Mines Division of Kennecott Copper Corporation, formerly known as the Nevada Consolidated Copper Company. Yellow -Property of the Consolidated Coppermines Corporation. Green --Consolidated Coppermines property under lease to Nevada Mines. The striking feature of the map is the crazy-quilt intermingling of the colors and the tendency of property lines to intersect ore bodies. For example, the westerly one-fourth of Nevada Mines' Copper Flat pit, source of most of the ore,up to date, is in Coppermines property. Nearly half of Nevada Mines' Veteran pit is on leased claims; and Nevada's new Deep Ruth shaft is on a right of way on ground originally owned by Coppermines. On the other hand, the original Ruth underground mine and the new Kimbley pit are on Nevada Mines property; and the Morris and Brooks opencut mines, the most important of Cop-

Jan 1, 1957

By Eugene McAuliffe

THE Coal Division undertook its most ambitious program this year at the New York meeting, with six full' sessions and a luncheon on Monday which had a record attendance and at which the newly elected officers for the Division were announced. Eugene McAuliffe, president of the Union Pacific Coal Co., Omaha, Neb., was unanimously selected as Chairman; J. B. Morrow, preparation manager of the Pittsburgh Coal Co., as Vice-Chairman; and H. E. Nold, Ohio State University, Secretary. During the past year two new and interesting activities were conducted by the Division directed at stimulating the interest of junior and student members. Reports were presented at the luncheon meeting by the chairmen of these commit¬tees. J. B. Morrow. chairman of the paper prize awards, and H. N. Eavenson reported on the work of the mining machinery manufacturers fellowship, the work on which was completed the first of the year. Several excellent papers are expected from these two groups for the next meeting of the Division to be held in Pittsburgh some time in the fall. The regular six-session program was filled from start to finish with interesting papers and much discussion, but unfortunately not enough time for the latter. The papers covered the field of prospecting, mining methods, preparation, utilization, mechanization, and safety, and all through the program we were constantly reminded of the value and need of research in the coal industry.

Jan 1, 1936

Andes Copper has an old camp and a new camp, both isolated until recent road improvements. The old camp is at Potrerillos and the new one at El Salvador, 25 road ,miles away. The company was incorporated in 1916 and the first mine, concentrator, leaching plant, smelter and town were built in the succeeding twelve years. The first blister copper was poured on January 24, 1927. Economic conditions determined the long development period but the end result was the design and construction of a mining complex that was all of a piece, unlike the piecemeal additions to El Teniente and Chuqui. The mining episode at Potrerillos came to an end in 1960 when the ore at La Mina became exhausted and the new mine, El Salvador was brought in. Both of these ore deposits come within four hpundred feet of the surface and had they been developed within the last five years might reasonably have been brought in as open pit mines. However, that is conjecture, and as it stands the operation at La Mina was so ideal for the mining method selected, blockcaving, it became a classic for the textbooks. On the other hand, El Salvador has turned out to be a blockcaving mine to test an engineer's skill. In mining the copper deposit at Indio Muerto mountain, there are ground conditions of every conceivable type. Tunneling in one section, the back can cave like sized pea gravel and only spiling can hold it; in another heading only the lifters are shot but often the rest of the round will sit down in one piece; elsewhere the bottom squeezes up and closes the drifts; and contrary to all other locations, there are sections where the block can be undercut without support. Today the scope of operations at Andes extends from mining to electrolytic copper. Ore is mined at El Salvador and the concentrator is also situated there. Concentrates pipelined 14 miles to Llanth, the water decanted, and then it is hauled by rail 40 miles and 5500 ft higher to the Potrerillos smelter and refinery. Potrerillos and El Salvador are respectively 90 and 70 miles from the port of

Jan 11, 1969

By S. H. Davis

THE pyrites used in making sulfuric acid in the United States have been largely imported from Spain and Canada, the Spanish imports amounting to nearly 1,000,000 tons per annum in the pre-war period. The greatly increased use of sulfuric acid and the cutting off of these Spanish imports, incident to war conditions, brought about a threatened shortage of sulfur supplies during the war period. The bituminous-coal mines of certain districts have, for many years, furnished a small tonnage of pyrite in the form of coal brasses. A mechanical concentrator at Danville, Ill., for a number of years, has been treating hand-picked lump pyrite and coal from the picking belt and from the mines and a small plant near Gillespie, Ill., for a few months has been recovering pyrite from washery refuse. Many mines throughout Illinois, Indiana, Western Kentucky, Ohio, and Pennsylvania have shipped an occasional car of the hand-cleaned lump pyrite. Only a very small percentage of the available pyrite has been recovered in this way, however, as usually the miners throw such lumps into the gob with slate and other impurities. It has been estimated that the western Indiana coal field could furnish more than 100,000 tons of pyrite per annum. The present production is very small. The possibility of furnishing the domestic trade with pyrites recovered as a byproduct from coal-mining operations appears attractive but there are certain features difficult to overcome. Pyrite, to be used in acid making, must meet with certain requirements as to size and purity. Lump ore for grate burners should be under 3 in. (7.6 cm.) and over 1 in. (2.5 cm.) in diameter. Fines for use in mecnanical roasters should be under quarter mesh. The material should be high in sulfur, free from arsenic and phosphorus, and as low in carbon as possible. The pyrite obtained from coal can be made to meet all the above requirements, but it is difficult to remove all the carbon. The pyrite in coal occurs as bands and nodules of varying thickness and size and of comparative purity, but mixed with this is more or less web sulfur. The web sulfur carries with it admixed coal, which may make the concen-

Jan 8, 1919

E. G. Spilsbury, New York, N. Y.:—Do I understand correctly that the rolls are at first simple cylinders, one longer than the other, and that flanges are subsequently formed on the longer roll as the result of wear only ? Mr. Payne :—The flanges are formed by the wearing of the shorter roll into the other, which is about an inch longer. When the roll-shells are new, the longer one has machined at each end a ridge about 1/8 in. or 0.25 in. higher than the face. These slight projections help to center and steady the rolls, by locating the flanges in advance. Possibly they might be left off at the start; but Mr. Frazee has found it better, in machining the new roll-shells, to turn such small flanges upon the longer one. In his practice the feed-stream is extended a short distance beyond the two ends of the shorter roll-shell. This allows a small amount of crushing to be done between the flange-ftices and the vertical ends of the shorter roll-shell, which prevents any ridges from forming at the ends of the shorter roll-shell.

Jan 1, 1913

University of New Mexico, Albuquerque, N M Requests for publications should be addressed to the Librarian of the University Papers of the Geological Series of the University are bound in volumes: Vol 1, vol 2, pt 1, and vol 2, pt. 2, and vol. 3 are out of print, but separates of the following papers may be had at a uniform cost of 25 cents each. Vol. 1? No. 1, Geology of the environs of Albuquerque (1898); 2, Occurrence of copper and lead in the San Andreas and Caballo Mountains (1898), 3, Geological reconnaissance in western Socorro and Valencia counties (1898); Geology of the San Pedro and Albuquerque districts (1898). , Vol 2: No. 1, Geology of the Albuquerque Sheet (1900); 2, Miscellaneous economic papers by Herrick (1900); 3, Geological reconnaissance in western Socorro and Valencia counties (1900); 4, Geology of the White Sands of New Mexico (1900); 5, Identifi¬cation of an Ohio coal measure's horizon in New Mexico (1900); 6, Cyanide process in New Mexico (1900). Vol. 3. No 3, The oil situation in New Mexico (1920), 4, Geology of Sandia Mountains (1922); 5, Oil and gas m New Mexico in 1923.

Jan 1, 1933

By Dol Duwez, R. H. Willens

A technique is described by which metastable alloy phases can be obtained by very rapid cooling from the liquid state. The results obtained so far have lead to; 1) extension of solubility limits beyond their equilibrium values, 2) new phases not found under equilibrium conditions, and 3) amorphous alloys. MANY new nonequilibrium phases have been found in alloys rapidly cooled from the liquid state. The technique used in these investigations essentially consisted of propelling a small molten globule of an alloy against the inside surface of a rotating copper cylinder. Since these original experiments were performed, the technique has been greatly improved. The purpose of this paper is to describe in detail, for the first time, a simple and efficient apparatus for producing foils of alloys which are rapidly cooled from the melt and to summarize some of the observations made on these alloys. I) FAST COOLING APPARATUS In the original fast cooling apparatus used by Duwez, Willens, and Klement,' the alloy was melted in a graphite container having the shape shown schematically in Fig. 1. A shock tube was attached to one end of the graphite part to supply the pressure for ejecting the molten globule. The globule was received on the inside of a rotating cylinder located about 0.5 in. from the exit of the graphite container. The globule trajectory made an angle of about 15 to 25 deg with the tangent to the cylinder at the point of

Jan 1, 1963

By James R. Cudworth

ENGINEERING has been taught at the University of Alabama for over a hundred years. The School of Mining and Metallurgy was authorized by the Board of Trustees in 1887 and four students were graduated in 1888. In 1919 the legislature directed that all mineral industry instruction in the state should be centralized at the University and designated the department of mining of the College of Engineering as the Alabama School of Mines and made financial provisions for carrying on both instructional and research work for the benefit of the mining industry of the state and for cooperation with the U. S. Bureau of Mines, which had established its Southern Experiment Station on the campus.

Jan 12, 1950

FEB. 17-The past month found the average citizen backed off just a little more into his blind corner staring glassily at hydrogen bombs, unbalanced budgets, John L. Lewis, more inflation, a rising wave of strikes, the country's only active battleship on a mudbank, a famous scientist in gaol as a traitor, a favorite actress on a Roman holiday, and rising mountains of potatoes, butter and eggs begging for destruction. About the only bright spot has been industrial activity and employment, but even these are menaced by the coal shortage. Most industries have orders on hand or in prospect to warrant high operations for some time to come. The trend of the Reserve Board's production index is upward except as strikes may interfere. There has been heavy buying at the seasonal merchandise shows, particularly in furniture and house-hold goods. The demand for goods of this kind illustrates greater confidence in the Spring outlook than was generally felt a year ago. Further, the demand also reflects improved market positions due to curtailment of output and reduction of inventories in 1949 and sustained consumer buying power. It demonstrates the strong support that is given directly to many businesses, and indirectly to all, by the phenomenal construction activity that is now under way. The Commerce Department places the number of new dwelling units started in 1949 at the new all-time high of 1,019,000.

Jan 3, 1950