Search Documents

By B. B. Betty

H. L. Burghoff.*—Have the authors any information on the effect of grain size in these materials? There is a material difference in the grain sizes shown for the Monel and the Inconel. Is a wide range of grain size normally found for each material, and, if so, what is its effect upon creep strength? 11. L. Eiselstein.—The grain size for Monel shown in the micrograph is the usual size found in that product. The grain size of Inconel is about the same as that, too. However, we have run tests on Inconel at higher temperatures than those reported in this paper, and have found that the coarser grain size has a better creep resistance; and that the grain size that gives the best creep resistance at 1600°F. is about 0.005 in. in diameter. We have no test on Monel with varying grain size. J. J. KANTER.†-It has been known for a long time that Monel metal exhibits ductility anomalies at elevated temperatures. Even in short-time test, it can be demonstrated in the range of 900°F. that there is a distinct falling off of the ability of Mone1 metal to elongate, and in rupture tests this shortcoming is still further accentuated. Knowledge of this rupture anomaly of Monel metal may be one of the reasons for which designer's approach certain high-temperature applications with reservations. The authors of this paper have merely demonstrated that for 900°F. the alloy has an ability to elongate 1.7 per cent over a period of some 2700 hr. Before any conviction can be expected from designers that Monel metal is applicable to stress design in such range of temperature, I think it is desirable to demonstrate the capacity for the material to elongate over a longer period of time than has been done in this presentation.

Jan 1, 1945

Discussion of the paper of K. Huessener, (Trans., vol. 53, pp. 402 to 4333, and of the papers of Linn Bradley, H. D. EGbert and W. W. Strong, pp. 303, 319. R. J. WysoR, So. Bethlehem, Pa. (communication to the Secretary*). —At our plant (Bethlehem Steel Co.), we have had several Bradshaw burners under course of construction and erection for some time, but up to the present we have not had opportunity to put them in service. I regret that I can not take part in the discussion with some actual results from these burners. Mr. Huessener properly emphasizes the importance of obtaining the highest combustion temperature practicable in boiler practice, which demands a near approach to perfect combustion conditions. The ideal burner is the one which, while meeting the various mechanical requirements, fulfills the above condition under a wide range of gas pressure. The question as to the relative value of hot raw gas and cold washed gas for boiler use is a very interesting one. I think that in the past the importance of low temperature of washed gas sometimes has been overemphasized. Mr. Huessener has pointed out that so far as temperature is concerned, no advantage accrues in washing gas below 100" F. In many plants, there is a notable operating economy in using furnace cooling water, which is appreciably warmer than the supply water. However, in a given type of washer, other conditions being constant, the lower the exit gas temperature the lower will be the dust content; this is equivalent to saying that the more washing water is used, other conditions being constant, the lower will be the dust content of the exit gas. For each type of washer there is a certain desired average temperature difference between inlet water and exit gas, concomitant with known average dust and moisture contents, and with economical operation. With the present tendency toward smaller stove checkers, it is generally agreed that gas for stove use should be cleaned to a dust content of 0.20 grain or less. The method employed and extent of gas cleaning are clearly problems for individual furnace plants. As a general proposition, wet washing is decidedly more attractive for furnaces smelting soft, fine Lake ores than for those reducing chiefly hard, lumpy ores, such as the foreign and domestic magnetites. In the former case the average moisture content of the gas is probably 35 grains per cubic foot, the dust content is relatively high and the top temperature relatively low. In our plant, the ore mixtures consist almost exclusively of hard magnetites. The average dust content of the gas leaving the dust catcher will average only about 2 grains and the moisture about 12 grains per cubic foot, corresponding to saturation at about 83" F. The temperature is fully 100" F. higher

Jan 1, 1917

By E. Motica

Ores containing uranium and vanadium minerals have been mined from the Salt Wash Member of the Morrison Formation from many localities in the Colorado Plateau region since about 1900. The most productive deposits are in a relatively small area in Southwestern Colorado referred to as the Uravan mineral belt. The mineral belt is a narrow elongate area in which uranium-vanadium deposits in the Salt Wash have a closer spacing, larger size, and higher grade than those in adjoining areas. Pre- 1948 ore production from the mineral belt was 655,000 tons averaging 1.91 per cent V2O5 and 0.28 per cent U3O8. Production during the 1948 to 1964 period was 7,900,000 tons of ore averaging 1.46 per cent V2O5 and 0.27 per cent U3O8. The ore deposits occur principally in the uppermost sandstone unit of the Salt Wash. This unit consists of sandstone lenses formed by a system of aggrading braided streams flowing in an easterly direction generally normal to the mineral belt. These lenses, referred to as channels, are as much as one mile in width and average about 50 feet in thickness and can be traced for several miles along their courses. Areas favorable for one deposits are recognized principally by the following criteria: ( 1) a host sandstone thickness of over 30 feet, (2) the presence of carbonaceous material in the host sandstone, and ( 3) gray mudstones and clays associated with the ore-bearing sandstone. The ore minerals are believed to have been precipitated from laterally migrating solutions; there is no apparent genetic relationship between ore deposits and tectonic structural features. Exploratory and development drilling from the surface is conducted in three phases: first, wide-spaced drilling to find and outline favorable channels; second, moderate-spaced drilling in favorable ground to locate ore deposits; and third, close-spaced drilling to block-out ore. Long-hole drilling from underground stations is used to find and delineate extensions of ore bodies being mined. Due to intense production since 1948 from shallow deposits, best potential for new deposits exists in areas where the ore-bearing unit is 600 to 800 feet deep.

Jan 1, 1968

By E. J. Rapperport, M. F. Smith

A presentation of the W-Ru constitution diagram is given. Techniques utilized in the determination of phase boundary values include electron micro-probe analysis of two-phased alloys and diffusion couples, as well as normal metallographic and X-ray methods. The primary features of the diagram are: 1) a terminal solid solution of ruthenium in tungsten with a maximum solubility of 23 at. pct Ru at 2300°C; 2) a terminal solid solution of tungsten in ruthenium with a maximum solubility of 48 at. pct W at 2205°C; 3) a o phase of maximum breadth about 6 at. pct based on the composition W3Ru2 which forms peritectically from the melt at 2300°C, and which decomposes eutectoidally at 1667 °C to form a twigs ten and 0 ruthenium; 4) a eutectic at 45 at. pct Ru and 2205°C with the products being o plus ß ruthenium. THE W-Ru diagram has previously been studied only in a cursory fashion. Raub and alter' obtained a 1400°C isotherm in which they observed no intermediate phases, and on which they established the limits of solubility as 36.5 at. pct W in ruthenium and about 1.5 at. pct Ru in tungsten. In addition, Obrowski2 found a o phase forming peritectically from the melt and existing only above 1650°C. Below this temperature the phase was presumed to decompose eutectoidally. The present work finds the diagram as given in Fig. 1. I) EXPERIMENTAL PROCEDURE The materials used for alloy preparation in determining the W-Ru constitution diagram were 99.9 pct pure ruthenium powder supplied by Baker Chemical Co., and 99.9 pct pure tungsten powder from General Electric Co. Typical analyses of these elements are given in Table I. Initial alloys at 10 at. pct intervals were prepared from the metal powders by the following method. Powders sufficient for 25 g of the alloys were weighed out with an accuracy of 0.1 mg and blended mechanically. After blending, the powders were compacted, in a steel die, at approximately 30,000 psi. The compacts were sintered in an electric vacuum furnace in order to remove adsorbed gases and to achieve partial densification prior to arc-melting. Vacua of 10-4 mm Hg or less were maintained in sintering as the furnace temperature was raised to approximately 2000°C. Sintering times ranged from 10 to 20 hr. The sintered compacts were arc-melted under a protective atmosphere of purified helium. Melting was conducted on a water-cooled copper hearth, utilizing a nonconsumable tungsten electrode. In the melting process, each alloy was turned over and re-melted on opposite sides from four to six times to ensure complete melting and to eliminate gross in-homogeneities. The arc-melter used had a vacuum capability of 5 X 10-6 mm Hg, and a leak rate of about 20 -liters per hr. Chemical analysis techniques for refractory metal-platinum group metal combinations are not well-established; therefore, composition control and determination depended principally upon weight-loss observations and calculations. This consisted in weighing each alloy after sintering and after arc-melting, and calculating the maximum and minimum composition values, assuming the total weight losses to be first all tungsten, and then all ruthenium. Since composition uncertainty was directly related to weight loss, care was taken to minimize losses in handling, compacting, and melting. Prior to homogenization and equilibration the as-arc-melted alloys were analyzed in several

Jan 1, 1964

By J. P. Morris

PREVIOUS investigations1,2 have shown that alloying elements in liquid iron influence the thermodynamic activity of sulphur and thereby affect the partition of sulphur between metal and slag in the desulphurization process. For example, the greater efficiency of desulphurization in the blast furnace as compared to the open hearth can be attributed in part to a higher level of sulphur activity in blast-furnace metal due to the higher concentration of carbon and silicon. In the present investigation, a short study was made of the influence of manganese on the activity of sulphur in liquid iron and iron-carbon alloys. In contrast to carbon and silicon, manganese was found to decrease the activity coefficient of sulphur; and in iron-carbon alloys it counteracts to some extent the influence of carbon. However, at manganese concentrations normally present in the blast furnace or open hearth, the effect of manganese is small. Since manganese sulphide has a limited solubility in iron, manganese can act, under certain conditions as a desulphurizing agent. Considerable data on the manganese-sulphur product in carbon-saturated melts were obtained in the investigation and have been included in this report. The experimental procedure was the same as that used in the earlier investigations on the effect of silicon' and carbon' on sulphur activity. Briefly, the method was as follows: The molten alloy, contained in a graphite or sintered alumina crucible, was brought to equilibrium at a constant temperature with a mixture of hydrogen and hydrogen sulphide of constant composition by bubbling the gas through the metal. Samples of' the melt were taken for analysis at regular intervals by suction through a 2 to 3 mm bore silica tube dipped into the metal. The experiments were run in a graphite spiral resistance furnace with melts weighing 50 to 60 g. The gas bubbling tubes were made of sintered alumina and were 5/16 in. OD, 1/16 in. ID, and 24 in. long. Equilibrium was assumed to have been attained when the sulphur content of the liquid metal reached a constant value. During an experiment there was a rapid loss of manganese from the melt by volatilization. To offset this loss, small additions of manganese were made periodically. The rate of manganese addition needed to maintain a constant manganese concentration was determined in preliminary tests. In all of the experiments, deposits of manganese sulphide formed above the melts in a cooler region of the furnace. Apparently, these deposits resulted from a reaction between manganese vapor and hydrogen sulphide in the gas. To prove that manganese sulphide did not volatilize from the melts to a measurable extent, an experiment was run in which helium was bubbled through liquid iron containing both manganese and sulphur. Although manganese volatilized rapidly in this test, there was no appreciable loss of sulphur. Volatilization of manganese sulphide from a melt would have led to an apparent equilibrium condition in which the sulphur content of the metal was lower than the true equilibrium value. The experimental results are shown in the first seven columns of Table I. The data in the last two columns were obtained from the previous work on the effect of carbon' and show what the results would have been in the absence of manganese but with temperature, gas composition, and carbon content of the metal remaining the same. Comparison of the last four columns show that, in the presence of manganese, the sulphur content of the metal increased at equilibrium and the activity coefficient of sulphur decreased. However, the results show that, for manganese concentrations below 3 pct, the effect of manganese is small. The values for activity coefficient of sulphur given in Table I were calculated from the following relations: S (in liquid metal) + H2 (gas) = H2S (gas) [l] K ph2s/?s X %S X phg = 0.00251 [2] where K is the equilibrium constant for the reaction, PH2S and ph2 are the partial pressures of hydrogen sulphide and hydrogen, respectively, and ?s is the activity coefficient of sulphur. The standard state for sulphur was taken to be a 1 pct solution of sulphur in pure iron. The numerical value for K at 1600°C was determined in the earlier work. For the purpose of showing graphically the results of the tests run at 1600°C, the activity coefficients of sulphur were recalculated so as to correspond to a manganese concentration in the metal of 2 pct in each case. In the calculation it was assumed that the increase in sulphur content of the metal at equilibrium caused by the presence of manganese

Jan 1, 1953

By P. M. Robinson, M. B. Bever

THE heats of formation at 273°K of the compounds InBi, In2Bi, and TIBi2 have been determined by metal solution calorimetry with bismuth as solvent. The published information on the thermody-namic properties of these compounds is limited. The structure of the compound InBi (mp, 383°K) is tetragonal of the PbO (B10) type.1 The compounds In2Bi (mp, 362°K) and TIBi2 (mp of highest-melting composition, 486°K) are now believed to have structures of the NizIn (B8) type273 and not the A1B2 (C32) structures reported earlier.4, 5 The compounds In2Bi and TIBi2 have limited homogeneity ranges at room temperature, while the compound InBi has no detectable homogeneity range.' Samples of the compounds were prepared from 99.99 pet Bi (Mallinckrodt Chemical Works), 99.999 pet in (American Smelting and Refining Co.), and 99.99 pet Tl (Amend Drug and Chemical Co.) by melting the components in sealed, evacuated Vycor tubes. The compounds InBi and in2Bi were of the stoichiometric compositions. The compound TIBi2 contained 40 pet T1; this composition was chosen because at room temperature the alloy of stoichiometric composition does not lie within the homogeneity range.' The melts were held approximately 50°C above the liquidus for 8 hr and then quenched into iced brine. The samples were homogenized for 48 hr at temperatures 20°C below the temperature of complete solidification. Metallographic examination of sections taken from the center and the ends of the ingots did not reveal second phases or segregation . The heats of formation were determined as the difference in the heat effects on solution of a compound and of a mechanical mixture of its components added from the reference temperature of 273°K to liquid bismuth at 623°K. The details of the calori-metric procedure and method of calculation have been described elsewhere? The calorimeter was calibrated by adding bismuth at 273°K to the bismuth bath at 623°K. The calculated values of the heats of formation of the compounds, listed in Table I, are based on a value of 4.96 keal per g-atom for the difference between the heat contents of bismuth at 273" and 623oK7 No published values are available for the heats of formation of the compounds InBi and In2Bi. Hultgren et a1.7 have calculated a value of -0.50 i 0.10 keal per g-atom for the heat of formation at 423°K of the compound TIBi2 containing 40 at. pet T1 from heat-content measurements in the range from 398" to 700°K and the heats of formation of the liquid alloy. The difference between this value and the value of -0.66 * 0.01 keal per g-atom at 273°K is too large to be attributed to a difference between the heat capacities of the compound and the components over the temperature range 273o to 423oK7 However, the direct determination of the heat of formation by a calorimetric method should give a more accurate value. The heats of formation at 273°K of the compounds InBi and In2Bi lie on a straight line when plotted as a function of composition, Fig. 1. The compound In2Bi, therefore, appears to be barely stable with respect to its neighboring phases. In order for the free energy vs composition curve to be concave towards the composition axis, the entropy change on formation of In2Bi must be more positive than that on formation of InBi. As the compounds are ordered,2, 3, 8 there is no configurational entropy change on formation. The difference between the entropy changes on formation of the two compounds, therefore, is probably associated with the vibrational entropies. In view of the low heats of formation, the changes in vibrational entropy, due to changes in bond strength on formation of the two compounds, are likely to be small. Owing to the volume contractions on formation of the two compounds,5 the vibrational entropies probably decrease slightly but the decrease of the vibrational entropy of InBi is expected to be larger than that of In2Bi.

Jan 1, 1965

By F. T. Davis

Many contributors have added to the fund of knowledge in the basic sciences related to mineral dressing during the past year. During 1964, the French edition of the Proceedings of the VIth International Mineral Processing Congress together with discussions was printed. Also, complete Preprints of papers delivered at the VIIth IMPC were published in September1. Over a third of the papers presented at VIIth IMPC dealt with fundamentals. COMMINUTION It has been postulated by Ponceleta that flaws need not exist before a stress is applied but rather the flaws are created at the tip of a propagating crack at a stress well below the theoretical breaking stress.

Jan 2, 1965

By B. V. P. Rao, H. L. Lovell, G. Simkovich

In the study described here, flotation tests were conducted on pure CaF2, on CaF2 doped at several concentration levels with either NaF or YF3, and on natural fluorite samples containing various amounts of impurities in an effort to extend previous knowledge of the influence of crystalline point imperfections on the flotation properties of solids. The results of these tests showed that although recoveries generally decreased as impurities increased, the differences in recovery were not nearly as striking as those detected in earlier experiments. A number of experimentalists have shown an interest in the way in which crystalline point imperfections affect the flotation properties of solids. As long ago as 1953, Welch hypothesized that it might be possible to control surface imperfections and thereby also control the flotation of solids.' A few years later, in some rather extensive work, Plaksin and his coworkers varied the surface imperfections of a number of compounds by oxidation or reduction processes and found that significant variations in flotation properties resulted.2-4 More recently, Simkovich showed that the recovery of both AgCl and PbS could be markedly varied by adding solid-solution impurities, which acted as doping agents, to these compounds.5 Then Mular studied the flotation of ZnO as a function of the doping agents Al2O3 and Li2O.6 Once again, it was found that these impurities, even in very low concentrations, had profound effects upon flotation recoveries. From an imperfection point of view, the defect structures of the compounds tested previously are as follows:7 PbS — amphoteric semiconductor with a Frenkel-type defect structure in the cation sub-lattice.8 AgCl - ionic conductor-Frenkel type defect structure? ZnO — n-type semiconductor, zinc ion interstitials and quasi-free electrons.10 All of these works undoubtedly bear some relation to the findings that the flotation properties of seemingly identical minerals from different ore deposits often exhibit extreme variation in flotation behavior, i.e., that small amounts of analytically undetectable impurities often have a great influence upon flotation

Jan 1, 1969

Jan 1, 1933

By E. R. MARBLE

THE introduction of a new fuel, such as natural gas, necessitates careful study where it has not been used previously. At the El Paso smelter natural gas required the installation of apparatus with which no one at the plant was familiar, either as to the type of equipment needed or as to the burning of the gas in it. Observation of existing installations of a similar character and assistance from gas engineers served as a basis to determine what was advisable to use. The gas line entering the plant goes to a metering station equipped with a duplicate system of pressure regulators, a temperature recorder and the gas company and smelter orifice meters in tandem. There are three distribution lines that can be inter-connected at a later date, if necessary, to assist in equalizing the plant load. All the larger lines are of heavy

Jan 1, 1930

By Julius Pohlman

The history of Niagara Falls, as currently told, is simple, and by that very simplicity it has been rendered plausible. AS the story runs, the Falls were once situated at Lewiston, 7 miles to the north of their present site; and, since all the rocks in this section are alternate hard and soft strata, the waters acting readily upon the soft shales caused their removal, and the overlying hard lagers, deprived of support, broke down under the weight of the large volume of water that rushed over them; and this erosive action has sent the edge of the fall more and more southward, until it now has excavated the seven-mile gorge between Lewiston and the village of Niagara Falls. (See Fig. 1.) As early as 1790" we find this theory advanced in a description of this region; and it has been practically endorsed by subsequent observers, the most prominent of whom was Prof. James Hall, the State Geologist of New York, who surveyed the Falls in 1841, and gave the most exact description of their surroundings in the publications of the State Survey.? Not until 1883 was the correctness of the accepted theory of the Falls questioned.‡ The geology of the basins of the Great. Lakes, as elucidated by Newberry,§ Speneer,ll and others, has added largely to a clearer understanding of the life-history of the Falls. The investigators have shown us that Lake Erie, as a lake, is, geologically speaking, quite young; that its valley was excavated in pre-glacial times by a series of rivers; and that the Maumee, Sandusky, Cuyaboga, Alleghany and other rivers carried the drainage of the surrounding

Jan 1, 1889

By Herbert Johnson

DURING the past 10 or 12 years very little information has been made generally available concerning the commercial possibilities of separating materials by means of static electricity; and yet during that same period important improvements have been made in various branches of the science of electricity, which, when taken together, and applied to electro-static separation, have resulted in important improvements in that art as well. For example, much improvement has been made in high-voltage electrical equipment such as full-wave vacuum-tube rectification and improved mechanical rectification. Great strides have likewise been made in the development of insulators for high-voltage work, not only in the materials used but also in the design of the insulators themselves. Again, in another field, the development of air-conditioning equipment has improved the technique of controlling the surface condition, through drying or humidifying, of the various materials that are passed through the electrostatic separator. In many authoritative publications and textbooks, the electrostatic separation process is declared to require a balance far too sensitive for general commercial application. For example, one publication1 in the past has referred to an unfavorable effect on the process caused by varying atmospheric conditions such as humidity. Some2 have even gone so far as to state that sunlight and shadows may seriously affect the separating efficiency of the process. Such statements may have been true in the early development of the art, when the source of static elec-tricity was derived from a friction disk machine, such as the Wimshurst. The Blake Mosher equipment and the work of Huff in applying motor-generator sets, transformers and mechanical rectification overcame much of this kind of objection to the commercial application of the elec-trostatic separating process.

Jan 1, 1938

By Thomas Read

IN speaking of immaterial problems of industry I am using the word immaterial in its original sense, not consisting of matter; not in its derived sense, unimportant. There is nothing of a paradox in saying that immaterial problems are the most important in human life, for His a matter of everyday observation that much of the news in the daily papers, and most of the world's best literature and drama, deal with human conduct that has for its motive forces that are but little concerned with material things. The engineer's preoccupation with physical forces, in extending his control over them, has not blinded him to the impor-tance of forces that, for want of a better word, I call immaterial; but he has considered that dealing with the one is his job and the other is not. All the evidence of the past decade indicates that the latter are so in-extricably interwoven with the former in modern in-dustrial life that the engineer will have to concern himself with them whether he wants to or not. Some of the most important of the problems arising from the action of these forces relate to the mental hygiene of the workers in industry. Mental hygiene in industry was concisely defined, in terms of the best present knowledge, by Dr. C. Macfie Campbell, speaking last April before the executive com-mittee of the Associated Industries of Massachusetts, and as his statement can scarcely be bettered, I quote it below: "The term mental hygiene is apt to appear vague. The actual stuff with which mental hygiene deals may be briefly reviewed.

Jan 9, 1927

By P. L. Weston, S. E. Khalafalla

A systematic study was made by the Bureau of Mines on the effect of so me hypothesized accelerators for the process of wustite reduction in carbon monoxide. When small concentrations of promoter materials in the order of 0.69 at. pct were added to the reducible charge, the rate of reduction to iron was increased. Promotion phenomenon prediction was made in light of a suyface reduction mechanism with the aid of Vol'kenshtein's effect regarding the propagation of crystal lattice disturbances by small amounts of relatively larger interstitial ions. The acceleration produced by a typical promotor, such as potassiunl, increases with protnoter concentration up to a maximum, beyond which the reduction rate decreases. Concentration for maximum promotion depends on the nature and physicochemical properties of the promoter. The extent of reduction rate enhancement is found to be directly proportional to the atomic volume and electronic charge of the additive. DESPITE the enormous volume of literature on iron oxide reduction, very little is reported concerning additive or impurity effects on this important metallurgical process. The beneficial effect bf calcium compound additions on the reducibility of iron oxide sinters has been reported by Tigerschiold,1 vor dem Esche,2 and Edstrom. Doi and Kasai~ found that the addition of lime or limestone to iron ores helps to break up any unreducible compounds, such as fayalite or ilmen-ite. and thus free the combined iron for reduction. Schenck et al. 5 suggested that the increased reduction rate obtained when adding lime could be accounted for by the instability of wustite in the presence of lime. Acid-base slagging reactions resulted in wustite disproportionation according to The dicalcium ferrite formed will yield iron and calcium oxide during reduction. Regenerated calcium oxide dissociates more wustite. This mechanism has been used by Seths and white7 to explain their experimental results. Recently, Strangway and ROSS' attributed the calcium carbonate acceleration of iron oxide agglomerate reduction to increased porosity, both initial as well as that developed during reduction. Aside from calcium carbonate, or oxide, no other promoter was noted in the literature, except for a brief mention by Barrett and woodg on the effect of sodium carbonate and aluminate as activators for the hydrogen reduction of magnetite at 600°C. The present investigation systematically studied a host of other promoters, including calcium and sodium, in an attempt to elucidate the mechanism by which promotion takes place and to fit the results into a simple chemical model. To attain this goal, the effect of promoter physical properties, such as atomic volume, electronic charge, and concentration are related to wustite reduction kinetics in this paper. Wustite reduction to iron, rather than the overall hematite reduction, was chosen since this reaction is known to be the slowest, and hence the rate-deter mining step for the overall iron oxide reduction process. EXPERIMENTAL PROCEDURE Raw Materials and Their Preparation. The pure or impregnated wustite pellets were prepared from minus 400-mesh chemically pure hematite powders. A known weight of hematite was thoroughly and uniformly mixed with a calculated weight of the additive. The mixed paste containing 35 wt pct water was gradually heated from 400" to 1200° C and fired at 1200°C for approximately 4 hr in an air atmosphere. After cooling, the sinter was pulverized to minus 100 mesh and pelletized into minus 4- plus 5-mesh spheres. Pellets were fired, similarly to the paste mix, air-cooled, sized, and stored. An appropriate weight of the charge (20 g) was placed in a zirconia reduction tube maintaining a uniform oxide bed height of 1 cm and a cross section of 7.1 sq cm for all of the test runs. The samples were supported in the vertical reaction tube by a bed of fragmented insulating firebrick plus 3- to 6-mesh alumina beads. The hematite was then transformed to wustite by reduction with a 30 pct CO2-70 pct CO gas mixture at 1000°C in a globar furnace. Complete conversion to wustite was ascertained by a continuous infrared gas analyzer recording the CO-CO2 content of the effluent gas until no carbon monoxide was absorbed from the inlet gas, and inlet-outlet gas analysis remained constant for 30 min. The wustite sample was then reduced with 100 pct CO at 100WC. From the recorded data, an initial rate of reduction was determined by the initial slope of the graph percent reduction vs time. In order to estimate the accuracy of the data, five separate determinations of the reduction curve of pure wustite, under otherwise identical conditions, were performed. The maximum deviation from the average reduction at 14 min amounted to 2 2 pct reduction. This deviation corresponds to 3.8 pct variation based on the percent reduction of the sample. Aiiy impurity effect below the limits of this maximum deviation was considered a spurious result. If the effect exceeded + 4 pct, then it was considered as a positive one. Considerable care was exercised in determining the initial rate from the slope of the initial segments of the curve. Each reduction curve was examined separately on large graph paper and the best tangent to the curve at zero time was drawn. The slope of this tangent was taken as a measure of the initial fractional reduction per minute. Although the time required to reach 50 pct reduction may be of special practical significance, initial rate measurements are invaluable in fundamental studies. These rates provide a measure of the process kinetics on the initial

Jan 1, 1968

By Earl Oliver

IN times like these, the A. I. M. E. and similar societies have their greatest usefulness. . . . Individuals and companies acting alone in the development of public opinion are merely voices crying in the wilderness. United and organized they make a great force that can and does influence public action. . . . What part, if any, then, shall the A. I. M. E. take in these great stabilization processes of civilization? Shall it help to give direction and force to scientific knowledge which comes within its field of activity or shall it merely develop more of it? . . . Is it the A. I. M. E.'s function to help bring system, order and direction out of this situation so that the world can again have forward economic movement, or should it rest on its oars until other agenciess develop that public understanding and direction so necessary for economic progress? As we understand the functions of the A. I. M. E. Petro¬leum Division, they are to discover and promote knowl¬edge for the benefit of society on the mining of oil and gas. To the individual member of the Petroleum Division, there are certain advantages of social and professional contacts, but the collective purpose is that described. And the individual is benefited by membership only as the Division measures up to the purposes of its existence. Consequently, the welfare of this Division and that of its members depends on the extent to which it keeps pace with the needs of society on matters relating to the mining of oil and gas.

Jan 1, 1932

By William Campbell

(Cleveland Meeting, October, 1912.) THE structure of iron and steel, though the object of so much study and research for the past 25 years, is by no means thoroughly understood. In the first place, we have three or more distinct iron-carbon thermal diagrams, each with its own supporters, and each representing a theory of the structure and constitution of cast-iron. In the second place, by reason of the fact that austenite, the solid solution of carbon in iron, decomposes in the solid state into ferrite, or pure iron, and cementite (Fe3C), and that quenching from above this transition-range, no matter how rapid, cannot entirely prevent the change and thus preserve the austenite by itself at ordinary temperatures, it happens that under the microscope we find, in addition to the ferrite, Fe3C, and austenite, which the thermal diagram of steel requires, it series of transition-products with distinctive structures, to which have ,been given the names martensite, troostite, sorbite, etc. Now these transition-products, in addition to the solid solution, austenite, have been the source of much controversy, at times very bitter. One side would insist that, say, troostite was an entity, which the other side would deny, pointing out that it must be a transition-mixture, with a particular structure. That austenite was a solid solution of carbon in iron has been denied by one school ; we have been told that Fe24C dissolved both Fe3C and Fe, and thus gave rise to a whole series of quenching-products-all this in spite of the fact that no matter how the thermal diagrams differ in regard to cast-iron, they all agree in regard to the solid solution, austenite, for Fe24C finds no place on the diagram. Thus it happens that while the authorities fight both in regard to the iron-carbon diagram and the structures met with in hard- * Associate Professor of Metallurgy, Columbia University in the City of New York.

Dec 1, 1912

By A. P. Anderson, J. H. Jensen, W. E. Breckoff

Bromine is the intermediate member of the halogen family of elements between iodine, a solid, and chlorine, a gas. The name is derived from the Greek "bromos," meaning stench. Bromine is the only nonmetallic element that is liquid at room temperatures with a melting point of -7.2° C and a boiling point of 58.78º C. Reddish brown in color, it dissolves easily in water to yield a red solution. Bromine volatilizes at ordinary temperatures to a red vapor that is very irritating to the eyes, nose, and throat. Density of the liquid is 3.12 and gas weighs 7.59 gpl at standard conditions. As the element is highly active, it exists in nature only as bromide compounds. Bromine was discovered by Antoine Jerome Balard in seawater bitterns in 1826 and first prepared in quantity in 1860. Distribution Bromine is widely distributed in nature and compounds occur in solution in natural brines, in seawater, saline lakes, oil and gas well brines, and in evaporite chloride minerals. The concentration of bromine salts ranges from 60-65 ppm in seawater to several thousand ppm in oil well brines and saline lakes. The distribution of bromine in marine evaporite minerals and in the solutions from which they crystallized was determined many years ago by H. E. Boeke (1908). Theoretical aspects regarding the geochemistry of bromine have been published in numerous papers (Raup and Mite, 1969). Bromine occurs in solid solution in carnallite and sylvite associated in potash deposits; in halite in salt beds; salt in oil shales; and in trona deposits. Its presence is useful as a guide in geochemical exploration. The analysis of small amounts of bromides in the presence of large amounts of chlorides is discussed by W. Schwerdtner (1963). Manganese, iron, and iodine may interfere with the determination. Other analytical methods are discussed at length in the literature (Stenger and Atchison, 1964). Sources and Reserves The sources and reserves of bromine, given in Table 1, appear ample to meet present and foreseeable requirements in all producing countries. With the occurrence of bromine salts in seawater and other brines, the potential for bromine production is worldwide. It has been estimated that 99% of all commercially recoverable bromine is in the ocean. However, actual subterranean brines having a higher bromine content than seawater will continue to be the preferred sources of bromine for the foreseeable future. [ ]

Jan 1, 1983

By Howard V. Sears

ArcHodrilling (Arcuate Hole Drilling) of short radius overhead curved holes from within the working level with a new, small-diameter in-the-hole drill produces tangible, assayable chip samples from the entire height of the projected mine level where the hole arcs down immediately in front of the working face. Drilling through the projected level with diamond coring tools produces samples showing the competence of roof and floor strata as well as the geological and economic characteristics of the ore. Hand-portable solid state electronic surveying instrument has been developed to survey the ArcHole and a convenient nomograph plotting record sheet converts survey digital readouts to hole inclination in degrees, to radius of curvature in feet, and to attitude of the plane of curvature from vertical in degrees, all without calculation. The ArcHodrilling system offers a tool with which the exploration geologist can more nearly assess the true potential of old mining properties being reexamined and to reduce the number of surface diamond drill holes needed to secure development data about new ore bodies. It gives the mine geologist an opportunity to secure those data at a fraction of the cost of drilling from the surface. The mining supervisor has a convenient, cheap tool to look ahead to know what he will be mining tomorrow. The mill supervisor has an opportunity to reduce his mineral loss in tailings by being able to anticipate the grade of his mill feed.

Jan 1, 1973

By Byron W. Cheever

In my paper on the estimation of manganese, etc., presented at the Halifax meeting, in September, 1885 (Transactions, xiv., 372), I said that the colorimetric process "can never be made to give reliable results." This statement was based on the results of many trials made by my assistant, Mr. E. D. Campbell, and myself, following in our work the printed and oral directions of others, and such modifications as suggested themselves from time to time. The accuracy of the statement having been questioned, I have, since then, endeavored to find some method of conducting the operation which would give accurate results; I have also tried the methods used by five different chemists; and I am not able to bring the process within the limits of an exact method. While it can fairly be ranked with the colorimetric carbon-process, and can be used for checking the operations of a steel plant, yet it requires more care to obtain uniform results, and is liable to greater variations from slight causes than the carbon-process, and, in my judgment, is not a safe method to employ when exact results are sought.

Jan 1, 1887

By B. C. Craft

The principal events in the oil and gas operations for Louisiana during 1933 have been the rapid development of the Converse field in Sabine Parish, the discovery of three new salt domes, one in North Louisiana and two in South Louisiana, increased development in the Iowa field on the Calcasieu-Jefferson Davis Parish line, and extensive geophysical operations over a wide territory. Other miscellaneous events worthy of mention are the continued leasing of prospective oil lands over a wide area, extension of production at the East Hackberry field, Cameron Parish, discovery of deep sands at Caillou Island, Terrebonne Parish, and the completion of several important wildcats. Despite proration, oil production showed a substantial increase during 1933. The total output for this area was 25,599,802 bbl. as compared with 22,507,387 bbl. during 1932. North Louisiana There were 111 oil wells and 47 gas wells completed in North Louisiana during 1933 as compared with 109 oil wells and 33 gas wells during 1932. North Louisiana oil production decreased approximately 692,625 bbl. in 1933 from its 1932 figure. The normal decline in the old fields was partly offset by increased production at the Zwolle and Converse fields in Sabine Parish. Acid treatment of wells in the Zwolle, Converse and Monroe fields was highly successful. The method of application has been described by H. K. Shearer, Geologist, Pelican Natural Gas Co., as fo1lows:l With tubing in the hole and standing valve removed, the casing is filled with oil to the surface. The limestone solvent is pumped in through the tubing, at the same time bleeding off enough oil from the casinghead to equal the volume contained in the tubing plus the volume of open hole to be treated. The amount of solvent used in most of the wells treated was 1000 gal., which is enough to dissolve about 11 cu. ft. of chalk or limestone. After the computed amount of oil is bled off, the casinghead is closed and the remainder of the solvent is pumped in at whatever pressure is necessary to force it into the oil-producing horizon. The solvent is followed up with enough oil to

Jan 1, 1934