Search Documents

By J. Parke Channing

IT IS most appropriate for mining engineers and in fact for all engineers to perfect themselves in leader-ship, because in the last ten years there has been a growing realization on the part of capital that there is no man who by capacity and training is better fitted to manage industrial production than the engineer. In high places the engineer and particularly the mining engineer is coming into his own. We have Mr. Hoover as Secretary of Commerce, Mr. Hammond as the head of the Federal Fact-finding Coal Commission, and Prince Caetani as Royal Italian Ambassador, all mining engineers. More and more in all industries is the manager more likely to be an engineer than he was five, ten, fifteen or twenty years ago, and the feeling is that the man who has had a technical training, whether from going to a school or from burning the midnight oil, makes a better manager than the man who has not. We find in mining that the best man for a manager is one who has had engineering, training. The manager who comes up from the office, from the purchasing department or from the transportation department may make a fairly good manager but he is never so good as the man who has had a technical training. He cannot speak the language of his staff.

Jan 5, 1923

By Warren K. Kourt

Many important discoveries of mineral deposits have been made as a result of routine exploration for oil and gas. Through the presentation of three hypothetical case histories, including cost data, the author shows how mineral evaluation can be performed during routine petroleum drilling operations and how mining companies and oil companies or oil operators can cooperate in such endeavors.

Jan 1, 1972

During the year terminating at the date for the third annual meeting of Engineering Foundation, the Board completed, its undertaking to sustain the National Research Council for one year. Assistance given in the organization of the National Research Council has been amply justified by the results. The Council is now well established in a 4¬story building at 1023 16th Street, N. W., Washington, and has recently secured another similar building near by in order to house its increasing force. The breadth, importance and volume of work done have steadily grown. Foreign offices have recently been established in London and Paris, Dr. H. A. Bumstead being in charge of the former and Dr. William F. Durand of the latter. The total expenditure by Engineering Foundation for the National Research Council was $9,036, derived partly from income of the endowment fund and partly from special gifts from Ambrose Swasey and Edward D. Adams. In May, Walter M. Gilbert was appointed Assistant Secretary of Engineering. Foundation, with headquarters in Washington, his services being contributed by the Carnegie Institution. He also became and has remained to date Assistant Secretary of the National Research Council. In September, resolutions were exchanged between the Engineering Foundation Board and the National Research Council, setting forth a policy of continuing reciprocal relationship, and a conference committee, Chairman M. I. Pupin, Dr. Charles Warren Hunt, and Gano Dunn, was appointed to inform the National Research Council of the readiness of Engineering Foundation to work upon definite problems sug-gested by the Council. No problems have yet been suggested.

Jan 5, 1918

By John W. Cloud

The delivery of blows upon roadway structures by the locomotive engine at high speed, althongh long recognized, has, perhaps, not been as generally understood in severity, relation to speed, and cause as is desirable in matters of such importance. Some points of explanation, with illustrative disgrams, are, therefore, submitted to your attention, preparatory to a note 011 " Steel for Bridges," also submitted. In order that a locomotive may run at high rates of speed with-

Jan 1, 1881

By K. V. S. Sastry

INTRODUCTION Flotation is by far the most important unit operation of mineral processing. Most of the common base metals are produced from flotation concentrates of metal sulfides. Flotation is proving to be a valuable process for producing non-metallic minerals such as ceramic oxides, silicates, clays and phosphate fertilizers. All these fltation separations are carried out on materials which are predominantly in the 10 to 100 micronssize range. The present practice of flotation circuits for the production of large tonnages of metallic and non-metallic mineral concentrates is fairly well understood, developed, and standardized. Two kinds of problems are encountered (1, 2) with fine particles smaller than 10 microns. First is the interference of the fine particles with the flotation of the coarser particles and the second is the poor flotation behavior of fine particles. In general, these problems are handled either by eliminating, minimizing, or ignoring the fines in the flotation circuit feed. In recent years, however, a considerable number of experimental and theoretical studies have been carried out to understand the flotation behavior of fine particulates. This literature is summarized in four review papers (2-5). Application of the conventional flotation techniques for the separation of mineral fines is known to be uneconomical, and to present several scientific and technological problems (1-5). The objective of this presentation is to examine the flotation behavior of fine particles in terms of their physical-chemical properties and to review the potential techniques of fine particle flotation. Specific reference to the problem areas and research needs will also be included in the discussion.

Jan 1, 1979

The Howe Memorial Lecture, in memory of Henry Marion Howe, Past President of the Institute, was authorized in April, 1923, as an annual address to be delivered by invitation under the auspices of the Institute by an individual of recognized and out standing attainment in the science and practice of iron and steel metallurgy or metallography, chosen by the Board of Directors upon recommendation of the Iron and Steel Division. The following were the Howe lectures and lecturers for the years indicated: 1924 What is Steel? By Albert Sauveur.

Jan 1, 1934

By Arthur C. Simmons

The area producing Pennsylvania-grade crude oil declined sharply in 1943, with a daily average production in the entire area of 71,056 bbl. as against a daily average in 1942 of 77,786. The total decline in the Pennsylvania-grade area amounted to 2,456,311 bbl., and 1,g81,z71 bbl. of this occurrcd within the state of Pennsylvania. The principal decline occurred in the Bradford field, where it was caused primarily by a drastic reduction in well completions. All of the zones in the Pennsylvania-grade producing area showed a decline except the part of Ohio that produces that grade, where production increased very slightly over 1942. Table I shows the average daily production by months for the several districts of the area. Table z is a comparison of the production in the two districts within the state of Pennsylvania. It is interesting to note that the Bradford field produced approximately half the total quantity of Pennsylvania grade but accounted for nearly three-fourths of the decline in production from the previous year. It is believed that this decline is ocasioned by restrictive price ceilings and a lack of adequate manpower to drill the necessary wells to maintain production. Stocks of Pennsylvania Grade At the beginning of 1942, stocks of Pennsylvania-grade crude totaled 3,196,000 bbl. and at the beginning of 1943 they totaled 2,626,000 bbl. At the end of 1943 the stocks of Pennsylvania-grade crude had declined to 1,95z,000 bbl. The available crude stocks have been almost completely consumed, as nearly all of the present crude stocks are "unavailable" and required for

Jan 1, 1944

By Thomas MacFarlane

IN smelting copper, lead, and silver ores, it is scarcely possible in every case to make analyses of the various parcels of ore, with the view of combining these and the fluxes so accurately as to yield, in the furnace, slags of exactly the most favorable composition. This is even more difficult with ores which require previous calcination, or with mattes which have been roasted in heaps. Even in cases where the greatest pains have been taken and the most elaborate calculations made beforehand, it frequently happens that variations in the working of the furnace interfere with the result so much desired. Generally, the practical metallurgist must be content with ascertaining the average composition of his ores and fluxes, making a calculation once for all as to the most advantageous mixture, and leaving slight changes in its composition to be taken care of as it is passing through the furnace. The various products then afford him the best material whereon to base his judgment as to the manner in which his smelting mixture is working. Of course the character of the slag is one of his chief guides, but it is not always possible from its outward characters alone to form a correct judgment as to its composition. Neither would it be possible or practicable to apply chemical analysis for this purpose, as it would be impossible to wait for its results while working a furnace. Abich was, I believe, the first to point out the relation existing between the composition of volcanic rocks and their densities, and to show that, the latter being ascertained, very correct conclusions

Jan 1, 1880

By D. W. Rudd, D. W. Vose, J. B. Vetrano

In an earlier paper the permeability character of Mo-0.5 pct Ti to hydrogen was described.' It was shown that this alloy is a more effective barrier to the passage of hydrogen than previously studied systems, i.e., copper,2 nickel,3 and several stainless steels.4 The permeability of Hastelloy B to hydrogen was investigated as a material having promising high-temperature structural properties which might have a low permeability to hydrogen. The general theory of permeation has been previously discussed,' and here only a summary of the more important results are given. It is found that except for very thin membranes, at low temperature, permeation of a gas through a metal barrier is determined by the rate of diffusion of the gas through the crystal lattice of the specimen, and that for hydrogen and the common diatomic gases, this passage involves dissociated particles as the diffusing species. The rate of permeation for hydrogen is therefore proportional to the square root of the pressure. It has also been found that the rate of permeation is inversely proportional to the thickness of the barrier. The apparatus used in this investigation was fundamentally the same as that employed in previous studies,' except that several simplifications result in the case of Hastelloy, since oxidation at the temperatures investigated is no longer a problem and welding of the specimen is relatively easy. A cross section of the membrane assembly is shown in Fig. 1. When finished, the assembly is about 5 in. long. The wall thickness is about 6 times the membrane thickness. The membrane (A) can be maintained at

Jan 1, 1963

By Thomas MacFarlane

In smelting copper, lead, and silver ores, it is scarcely possible in every case to make analyses of the various parcels of ore, with the view of combining these and the fluxes so accurately as to yield, in the furnace, slags of exactly the most favorable composition. This is even more difficult with ores which require previous calcination, or with mattes which have been roasted in heaps. Even in cases where the greatest pains have been taken and the most elaborate calculations made beforehand, it frequently happens that variations in the working of the furnace interfere with the result so much desired. Generally, the practical metallurgist must be content with ascertaining the average composition of his ores and fluxes, making a calculation once for all as to the most advantageous mixture, and leaving slight changes in its composition to be taken care of as it is passing through the furnace. The various products then afford him the best material whereon to base his judgment as to the manner in which his smelting mixture is working. Of course the character of the slag is one of his chief guides, but it is not always possible from its outward characters alone to form a correct judgment as to its composition. Neither would it be possible or practicable to apply chemical analysis for this purpose, as it would be impossible to wait for its results while working a furnace. Abich was, I believe, the first to point out the relation existing between the composition of volcanic rocks and their densities, and to show that, the latter being ascertained, very correct conclusions

Jan 1, 1880

By Arthur C. Simmons

The area producing Pennsylvania-grade crude oil declined sharply in 1943, with a daily average production in the entire area of 71,056 bbl. as against a daily average in 1942 of 77,786. The total decline in the Pennsylvania-grade area amounted to 2,456,311 bbl., and 1,g81,z71 bbl. of this occurrcd within the state of Pennsylvania. The principal decline occurred in the Bradford field, where it was caused primarily by a drastic reduction in well completions. All of the zones in the Pennsylvania-grade producing area showed a decline except the part of Ohio that produces that grade, where production increased very slightly over 1942. Table I shows the average daily production by months for the several districts of the area. Table z is a comparison of the production in the two districts within the state of Pennsylvania. It is interesting to note that the Bradford field produced approximately half the total quantity of Pennsylvania grade but accounted for nearly three-fourths of the decline in production from the previous year. It is believed that this decline is ocasioned by restrictive price ceilings and a lack of adequate manpower to drill the necessary wells to maintain production. Stocks of Pennsylvania Grade At the beginning of 1942, stocks of Pennsylvania-grade crude totaled 3,196,000 bbl. and at the beginning of 1943 they totaled 2,626,000 bbl. At the end of 1943 the stocks of Pennsylvania-grade crude had declined to 1,95z,000 bbl. The available crude stocks have been almost completely consumed, as nearly all of the present crude stocks are "unavailable" and required for

Jan 1, 1944

(The following list contains the names of those members of the Institute of whose connection with military service we have only recently become acquainted; it also includes the names of a few who have recently been promoted or transferred. A complete list was published in the Year Book, issued as a supplement of the Bulletin for March, 1918.) ANDREWS, CLARENCE W., 2d Lieutenant, 12th Batt. Infantry Replacement Regiment. ANDREWS, JOSEPH C., Ordnance Dept., U. S. A. ARLUCK, A. A., Headquarters, 1st Corps of Artillery, A. P. O.. No. 759, A. E. F.

Jan 9, 1918

By J. Boldy

Discovery of the Delbridge massive sulfide deposit in the Noranda district of Quebec resulted from an appreciation of the significance of a mercury leakage halo as a lithochemical pathfinder to blind ore. Its location, relative to a geologically inferred ore-bearing horizon within complex volcanic stratigraphy was also a factor. Systematic sampling of microfractures present in outcrops delineated a diagnostic anomaly, drawing attention to an area considered prospective for buried ore. The massive sulfide deposit was subsequently found to be blind and topped at the 110-m (360-ft) level.

Jan 1, 1985

By Ira B. Joralemon

INDIVIDUALS and small companies have discovered and brought into production the mining districts of the United States. Hardly an exception comes to mind, save for the disseminated copper properties and the great iron mines. In spite of this fine record that has made possible the industrial greatness of the country, mining by small companies and by individuals has become a vanishing phenomenon. In Nevada, the lair of rugged individualism, there are fewer operating mines and fewer miners than at any time since the 1860's. The situation in other states is nearly as desperate.

Jan 8, 1950

By Robert B. Fulton

Staurolite, an iron aluminum silicate mineral, is used industrially as the source of aluminum in portland cement manufacture in areas where the aluminum constituent is not economically available from shale or argillaceous limestone. It is also used as a high value- in-use sand blasting agent and as a premium grade foundry sand. It is produced by E. I. du Pont de Nemours & CO. as a coproduct in titanium mineral production in Florida where it was first recovered on a commercial scale in June 1952 from the Pleistocene sand deposit known as Trail Ridge. In the Trail Ridge deposit it comprises about 36 of the heavy minerals, the principal other heavy mineral constituents being ilmenite, leucoxene, rutile, zircon, kyanite, sillimanite, and tourmaline. Staurolite and the other silicate nonconductive heavy minerals are separated from the conductive titanium minerals on high-tension separators. The silicates are then separated from one another magnetically, the staurolite being relatively magnetic. In the total processing, 200 tons of raw sand yield 7 tons of heavy mineral concentrate from which about one ton of staurolite is recovered. Staurolite production is approximately 100,000 net tpy. No other commercial production of staurolite is known. This process yields staurolite concentrates of the characteristics given in [Table 1]. These concentrates are sold as three products with the size distribution of subrounded particles shown in Table 2. All three grades are used in sand-blasting for cleaning metal, for paint removal, and for cleaning buildings. Staurolite compares favorably with lower unit cost abrasives, such as boiler slags and mineral aggregates, in applications where the abrasive is used only one time and is not recovered. Because it is hard, fine, clean, and dense it can reduce blasting time, with less material reportedly being required

Jan 1, 1975

By B. H. Mot

Underground water has been one of the greatest problems in sinking mine shafts, sealing existing shafts, and driving headings under streams. In the preparation of a proposed shaft or existing shafts for elimination of water leakage, advances have been brought about through the use of a controlled grouting method. The modern method to divert water from proposed shaft sites is known to us as pre-grouting, and from existing shafts, as controlled pressure grouting. This method involves the solidification of the surface and rock by the injection of a liquid mixture of

Jan 1, 1949

By Heinrich Ries

The clay-resources of Colorado are but little known, for the reason that little has been published concerning them, and also on account of the hitherto small demand for clay products in the Rocky Mountain region. At the present day the wares manufactured from clay which are used in Colorado include common and pressed brick, terracotta, sewer-pipe, pottery and refractory articles. Most of these are brought from a considerable distance; but with an increasing demand for such goods in the West and a better knowledge of the available materials, there should be considerable expansion in the clay-working industry of Colorado in the future. The notes here presented are an abstract of those collected by the writer in October, 1896, in a reconnaissance of the clay-bearing formations of Colorado. Clay-bearing Formations. We may roughly divide the clay-bearing formations of Colorado into three groups : 1. Loess and alluvial deposits. 2. Jura-Trias and Cretaceous clays. 3. Tertiary clays. . The loess forms an extensive deposit of large area, though not very thick, extending from north to south across the State, and eastward from the foot-hills. It is generally a very sandy clay, with little plasticity, and is underlain by a gravelly stratum, which determines the workable depth. Clay similar to the loess is found underlying the river terraces in many of the broader valleys, such as those of the Arkansas, Grand River, etc. The Mesozoic formations extend along the eastern edge of the Rocky Mountains, and also occur in some of the deeper valleys tributary to the foot-hill belt. They consist of a great series of interbedded shales, sandstones and limestones of Jura-

Jan 1, 1898

By Harold M. Mooney

RESISTIVITY measurements for determining depth to bedrock, water table, and other geologic discontinuities have had only limited success. Many of the difficulties can be attributed to complex geology and to basic limitations of the method; current flow through a continuous medium is a diffusion phenomenon, emphasizing irregularities near the source and smoothing out those at a distance. Some of the failures, however, are due to careless field work and incompetent interpretation. A forthcoming publication1 may help to reduce difficulties of this sort. The writer here attempts to bring order into the multiplicity of interpretation methods and, to a limited extent, to evaluate them. For all methods, the field data to be interpreted consist of apparent resistivity values plotted against electrode separation, Fig. 1. The interpretation should give depths to one or more geologic horizons. Direct currents and the Wenner four-electrode configuration will be assumed, since these are widely used, although the interpretation problems remain essentially the same for other electrode configurations. Alternating currents higher than, say, 20 cycles per second introduce complications beyond the scope of this paper. Three approaches to the interpretation problem have been used. These may be called empirical, theoretical curve matching, and direct. Many techniques have been proposed, but each can be reduced to one of these approaches and to a single geologic idealization. This idealization rests on the following assumption: the earth in the limited volume of interest can be approximated by a horizontal sequence of layers, each homogeneous and isotropic in its electrical properties. This seemingly restrictive assumption has proved to have practical value, although future work should aim at removing some

Jan 1, 1955

By Morris Cohen, William P. Kimball

This paper deals with the calculation of the composition of the infinitesimal trace of alloy that transfers from the liquid to the solid state at each temperature during the equilibrium solidification of a binary solid solution, and which thereby enables the compositions of the coexisting liquid and solid phases to follow along the liquidus and solidus lines respectively during the cooling. A general expression for the composition (6) of the liquid-to-solid transfer at each temperature has been derived: d= Zlxl(xl - P) + Zsxs(P - xs)/Zl(xl - P) + Zs(P - xs) [1] where ZL and Zs are the slopes of the liquidus and solidus lines at the given temperature, Xl and 28 are the compositions of the stable liquid and solid phases at the same temperature, and P is the composition of the alloy under consideration. The 6 equation is valid for the process of equilibrium heating as well as cooling, and may be applied to vapor-to-liquid, vapor-to-solid, liquid-to-liquid, and solid- to-solid transfers if the corresponding equilibrium diagrams are known. The d-versus-temperature curves for two alloys P1 and P2 are shown in Fig. I. In each case, the liquid-to-solid transfer has the same composition as the stable solid phase only at the temperature of the beginning of solidification, and has the same composition as the stable liquid phase only at the temperature of the completion of solidification. At each intermediate temperature, the composition of the liquid-to-solid transfer differs by a finite amount from those of the two coexisting phases. Therefore, during equilibrium cooling, the transfers must merge into the solid phase from the liquid without forming a transition phase; otherwise the condition of equilibrium would be violated. At any given temperature during solidification, the composition of the liquid-to-solid

Jan 1, 1941

By William P. Kimball, Morris Cohen

This paper deals with the calculation of the composition of the infinitesimal trace of alloy that transfers from the liquid to the solid state at each temperature during the equilibrium solidification of a binary solid solution, and which thereby enables the compositions of the coexisting liquid and solid phases to follow along the liquidus and solidus lines respectively during the cooling. A general expression for the composition (6) of the liquid-to-solid transfer at each temperature has been derived: d= Zlxl(xl - P) + Zsxs(P - xs)/Zl(xl - P) + Zs(P - xs) [1] where ZL and Zs are the slopes of the liquidus and solidus lines at the given temperature, Xl and 28 are the compositions of the stable liquid and solid phases at the same temperature, and P is the composition of the alloy under consideration. The 6 equation is valid for the process of equilibrium heating as well as cooling, and may be applied to vapor-to-liquid, vapor-to-solid, liquid-to-liquid, and solid- to-solid transfers if the corresponding equilibrium diagrams are known. The d-versus-temperature curves for two alloys P1 and P2 are shown in Fig. I. In each case, the liquid-to-solid transfer has the same composition as the stable solid phase only at the temperature of the beginning of solidification, and has the same composition as the stable liquid phase only at the temperature of the completion of solidification. At each intermediate temperature, the composition of the liquid-to-solid transfer differs by a finite amount from those of the two coexisting phases. Therefore, during equilibrium cooling, the transfers must merge into the solid phase from the liquid without forming a transition phase; otherwise the condition of equilibrium would be violated. At any given temperature during solidification, the composition of the liquid-to-solid

Jan 1, 1941