Search Documents

By Charles F. King

The only investigations on record of the reactions occurring (luring the Bessemer blow are of charges containing a large percentage of manganese, with the exception of' two partial analyses by Snelus and Barker of the English method, where a low percentage of manganese was used. They do not give the analysis of the spiegel, [lor do they report any graphitic carbon after the first stage of the process. Both report only traces of manganese after the first stage until the addition of spiegel. The slags corresponding to the samples of metal were not analyzed.

Jan 1, 1881

By W. G. Fischer

This paper attempts to close the gap between extensive rock testing with field measurements and the mine operator's need for safe mine layouts and alternatives. It was found that many of the variables that influence mine geometry and worker safety are relatively unimportant while others are critical. The development of empirical relationships that tie the critical variables to the safe useful life of a trona mine layout and observations made in 140 production areas where the variables were researched over a 15-year period are discussed. The concepts presented may have applicability in mine design for other bedded deposits.

Jan 1, 1986

By P. Sen

Frequently during the processing of minerals very fine particles are generated which are difficult to recover by conventional separation techniques and are rejected with waste water from mills. A method has been evolved for the continuous recovery of such fines by allowing the suspensions to flow through a rotating cylinder. Theoretical analysis of the trajectory of particles have shown that the efficiency of separation increases with R.P.M., tube diameter, particle diameter and density. Experiments carried out with the overflow from a hydrocyclone containing particles in the size range of 2-10 microns gave a separation efficiency of 60-70% with an R.P.M. of 3500 of the rotating tube.

Jan 1, 1980

By T. Egleston

In the year 1881 I presented to the Institute two papers containing the resnlts of researches on gold, in which I endeavored to make plain some of the causes of the losses in the working of gold-ores. Since that time I have continued this investigation at intervals with the following results. In the papers previously presented to the Institute I made no attempt to make compounds containing more than two substances. Since then I have endeavored to make more complex compounds. The experiments consist in fusing mispickel free from gold with a certain amount of metallic gold, and experimenting with that; also fusing the same mineral with sulphide of antimony, and fusing iron pyrites with gold and compounds of antimony. The mixture was made with mispickel taken from a vein not far from Stamford, Conn., absolutely free from gold. It was fused

Jan 1, 1884

ST. LOUIS SECTION H. A. BUEHLER, Chairman, CHARLES T. ORR, Vice-Chairman., THOMAS T. BREWSTER, Vice-Chairman, L. L. HUTCHISON, Vice-Chairman, W. E. McCOURT, Secretary-Treasurer, Washington University, St. Louis. CHARLES J. ADAMI, EUGENE MCAULIFFE, A. C. TERRILL, JAMES A. CASELTON, JAMES D. ROBERTSON. The annual meeting of the St. Louis Section was held at the St. Louis Club, Saturday evening, Mar. 10, 1917. Philip N. Moore, President, and Bradley Stoughton, Secretary of the Institute, were the guests of the Section. The meeting was preceded by a dinner, at which 70 were present, and was presided over by F. W. DeWolf. Addresses were made by Mr. Moore and Mr. Stoughton. The routine reports of the officers were- presented and the Executive Committee named above was elected for the current year. The special business of the meeting was a report of progress concerning the arrangements for the Institute meeting to be held in the St. Louis Section district, Oct. 8 to 13, 1917. The general program for the meeting met with the cordial approval and cooperation of the members of the Section. It was evident that the members are united in an endeavor to arrange a successful meeting. W. E. McCOURT, Secretary.

Jan 4, 1917

An appropriation of $4000 was made to the United Engineering Society for the support of the work of the Engineering Council. It was resolved that the proposed amendments to the Constitution, regarding requirements for membership, be sent to the membership without comment thereon by the Board of Directors. Forty-one members, and three associates were elected. The status of two junior members was changed to member. The resignation of one member was accepted. The dues of nineteen members who are engaged in active duty with the Allied armies were remitted. B. B. Thayer was elected a member of the Board of Trustees of the United Engineering Society for a period of three years, to succeed himself. John H. Janeway was elected a member of the Library Board for a period of four years, to succeed himself. George C. Stone was elected a member of the Library Board in place of E. F. Roeber, deceased. E. Gybbon Spilsbury was elected representative of this Institute on the John Fritz Medal Board of Award, to succeed himself. J. Parke Channing was elected a member of the Engineering Council for a period of three years, to succeed himself.

Jan 1, 1918

By J. C. Holm

Although the main constituents of Portland cement are the oxides of calcium, silicon, aluminum, and iron, characteristics of the cement are seriously affected by such contaminants in the raw materials as magnesium, phosphorus, sodium, potassium, sulfur, and others of lesser importance. Sources of cement raw materials comprise a long list of minerals occurring in nature in various degrees of purity. The calcareous raw materials are generally limestone of purity varying from calcite to cement rock (a low-grade limestone of natural, almost correct chemical composition), chalk, marl, seashells, coral, and coral sand. The argillaceous raw materials supplying silicon, aluminum, and iron are mainly various forms of clay and shale, to which may be added silicious sand, iron ore, bauxite, or kaolin for minor adjustment of the chemical composition.

Jul 1, 1956

By W. A. Boyer, A. W. Beck

At the Morning mine of American Smelting & Refining Co. it was particularly important that there be a means of signaling the engineer from the moving cage in the shaft. Because of the shifting ground in which the shaft was located, buckling timber made it extremely difficult to keep a continuous bell line serviceable. In 1930 engineers considered a moving contact pantograph arrangement between the cage and two stationary messenger wires strung on insulators in the shaft compartment next to the cage. The idea was abandoned because falling material in the shaft and speed of hoisting made it difficult to maintain communication. Later in 1934 a manufacturing company was consulted about the use of an electric eye or a radio signal. As the shaft was located in a return air stream of nearly 100 pct relative humidity, there was too much fog for the electric eye to be used. The radio signal was considered, and it was believed feasible to generate electric static on the cage, locating a radio receiver at the top of the shaft, but the manufacturing company's research department was too busy to work on it at that time.

Sep 1, 1955

By E. A. Metzbower

STEREOGRAPHIC projections of hcp metals depend upon the c/a ratio. Hu1 has recently published standard projections for titanium (c/a = 1.5873) of the (000l), the basal plane, the (1010), the most prominent slip plane, and the (1012), the most prominent twinning plane. Caplan et a1.2 and Hul have also published tables of angles between poles of planes, between directions, and between directions and poles of planes. From these tables standard projections and double stereograms can be constructed. However, by using the on-line CALCOMP plotter with a CDC 3800 computer, direct plots of standard stereographic projections of titanium (c/a = 1.587) have been made.

Jan 1, 1970

By Brahm Prakash, R. Schuhmann

Chemical conditions for flotation and nonflotation of cassiterite and fluorite with oleic acid as collector and with alizarin dyes as modifying agents were studied by means of small-scale, vacuum-flotation tests. Artificial cassiterite was prepared for these tests by high-temperature methods, especially by crystallization from borax melts.

Jan 5, 1950

By W. H. Adams

At the present time all the larger and better chemical works of Europe and the United States have introduced, as essential factors in the economical manufacture of sulphuric acid, both Glover towers and Gay-Lussac absorbing columns. The clear exposition of facts given by Bode and Lunge in their very valuable technical contributions since 1870 has slowly but surely brought about radical changes from the old methods of manufacture ; but while the Gay-Lussac column has been known since 1827 and the Glover tower was originated in 1869, yet no theoretical treatise covering the subject fully was given to the world until 1876, when the various contrivances for demonstrating nitrous vitriol were described and criticized by Fr, Bode in a paper "On the Glover Tower" which obtained the great prize of the Berlin Society for the Promotion of Industry.*

Jan 1, 1887

By Norman Weiss

There was a time in the early history of man's use of metals when ore could be directly reduced to usable form by the use of fire. In those days the term "milling," or its many synonyms signifying the concentration of an ore's metallic con- tents before smelting, was little known. Centuries later, even before Agricola, or even before the Greek and Roman civilizations, simple means were found to concentrate metallic minerals that possessed special characteristics such as high specific gravity, hardness, magnetic response, or simple appearance. In this way, the art of milling became valuable to civilization because it eliminated most of the cost and labor of transporting and melting the worthless nonmetallic part of an ore. As civilization became more dependent upon metals and solid fuels, the art of ore dressing (one of our synonyms) increased in importance and complexity, until today it has become a gigantic industry firmly based upon a mature but rapidly advancing technology. Technically trained people are needed in growing numbers to serve this industry.

Jan 1, 1970

By David A. Martin

Resource based companies have been inundated with changes in government tax legislation during the past few years. To cope, capital investment planning analysts have turned almost completely to computer simulation modeling to react quickly enough to determine the effect on their companies' major investment projects and on the projected financial picture of the companies. This paper will examine various royalty and tax structures as applied to coal, oil and gas, and minerals in the U.S. and Canada with particular emphasis on recent changes in the Canadian tax scene and their implications to capital project economic evaluation in other parts of the world.

Jan 1, 1977

By Robert R. Turner

This paper discusses wet and dry primary autogenous and semi-autogenous grinding, including a description of the equipment and its mode of operation, testing and the scaling-up of test data. Lists of selected literature references are included.

Jan 1, 1982

By Robert Sisselman

Cesium metal isn't on the government's list of priority materials for stockpiling, but it may be getting a big lift in that direction. Both the National Aeronautics and Space Administration (NASA) and the Atomic Energy Commission (AEC) have committed themselves to a long-range research program the outcome of which may boost annual domestic production to 37,000 lb by the year 2000. This would represent a sixfold increase in cesium consumption over the figures reported in 1968. To accomplish this dramatic increase, there must he some equally dramatic breakthroughs. Recent research efforts designed to shake the metal from its lethargic status in world markets have been concentrated in the areas of ion propulsion, thermionic power conversion and magnetohydrodynamic (MHD) power generation. The activities in these areas, all of which attempt to make use of cesium's unique properties, may lead to a practical method for converting nuclear energy into electricity and a cheaper and more effective alternative to liquid propellants used in long-range space flights.

Jan 1, 1971

By M. L. Jeremic

Observations of ground behavior in mining the Choka Dulkan ore body have been described. Ore recovery was limited to approximately 60% because unconsolidated hydraulic fill did not permit either the widening of stope spans nor secondary ore recovery from pillars. Stope undercutting induced high stress concentrations. However, as extraction progressed, ground conditions improved but before extraction was complete they deteriorated again. After completion of a stope, the remnant rib and crown pillars continued to be deformed by other stresses for some time.

Jan 1, 1979

By V. R. Garfias, R. V. Whetsel, J. W. Ristori

World consumption of petroleum and related fuels for civil purposes in 1939 was close to 2,024,000,000 bbl., or approximately 110,000,000 bbl. more than in 1938, the United States accounting for 96,000,000 bbl. of the increased amount. With the annexation of Czechoslovakia and part of Poland, civil consurnption in Germany during 1939, notwithstanding sevre rationing in the last four months of the year, was 54,000,000 bbl., or only 1,600,000 bbl. less than in 1938, and domestic production of pctroleum and related fuels was some 34,000,000 bbl. short of civil consumption. The mounting petroleum requirements of the military forces of greater Germany are, of course, not included in these figures of civil consumption. To supply this deficiency Germany now must rely almost exclusively on the Rumanian fields, which in 1939 produced about 35,000,000 bbl in ewes, of the Rumanian civil consumption. However, these fields arc supplying and have supplied for years the oil requirements of the neighboring

Jan 1, 1940

By J. A. Rajala, R. W. Smith

The effect of increasing ionic strength, via monovalent and divalent ions, on alkyl sulfate flotation of hematite and quartz war investigated. The effects of collector chain length and pretreatment on this flotation were also studied. Sodium hexadecyl sulfate was shown to be a superior flotation collector to sodium dodecyl sulfate for recovery of hematite when there was no salt addition. Similar observation were made when sodium sulfate or sodium chloride was used to control ionic strength. Sodium dodecyl sulfate floated hematite better than its longer chutited counterpart under conditions of low pretreatment temperature and increasing calcium chloride concentration. The flotation recovery for all salt containing pulps was almost always improved after preboiling. Most of the results obtained when the pretreatment temperature was raised were attributed to increased solubility of the collector.

Jan 1, 1984

THE Institute assembled in the metallurgical lecture-room of Pardee Hall, Lafayette College, at 7 o'clock P.M. on Tuesday evening, October 21st. The session was opened by the President, R. W. Raymond, with an address on Mining Industry as illustrated at the Vienna Exposition. The second session was held on Wednesday morning. The Council reported the following names for election as members and associates. They were unanimously elected. †Ayres, W. S., - Easton, Pa. *Baker, Prof. A. L., - Easton, Pa. †Browne, Thomas Nicholl, - Hamilton, Nev. *Carter, Frank, - Pottsville, Pa. *Davis, E. F. C., - Pottsville, Pa. *Fox, Prof. J. G., - Easton, Pa. *Haight, Ogden, - Etna, Pa. †Hall, Norman, - Sharon, Pa. *Knap, Joseph, - Fountain Mill, Pa. †Miller William McKeen, - Easton, Pa. †Pardee, I. P., - Easton, Pa. *Plater, John E., - Eureka, Nev. *Platt, Joseph L., Jr., - Franklin Furnace, N. J. *Plumb, W. H., - Mauch Chunk, Pa. *Reis, George L., - New Castle, Pa. *Samuel, Edward, - Philadelphia, Pa. *Smith, William Allen, - Trenton, N. J. *Smock, Prof. John C., - New Brunswick, N. J. *Weberling, Charles, - Salt Lake City, Utah. Also the following as foreign members Beaulieu, Ad. le Hardy de, - Brussels, Belgium.. Beaumont, Major Fred., - London, England. Beck, Alexander, - Mons, Belgium. Bodmer, J. J., - London, England. Brassert, Berghauptmann, Dr., - Bonn, Prussia. Brogden, James, - London, England * Members. † Associates.

Jan 1, 1874

By A. G. Journel

Accurate prediction of recoverable reserves are key to the development and planning of a mining operation. Recovery functions for tonnage, quantity of metal, and ore grade are defined and two approaches for their estimation are proposed. The indicator kriging (IK) approach draws on the data rank orders, whereas the multigaussian (MG) approach relies on a grade multivariate distribution hypothesis. Although based on different premises, both approaches yield remarkably similar, and reasonably accurate, estimates for recoverable reserves.

Jan 1, 1986