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Jan 1, 1938

By Franz Posepny

CONTENTS. Introduction. Part I. General Facts And Theories. [ ]

Jan 1, 1902

I AM sure you know that it is necessary to draw the gold into wire in order to make gold cloth, gold embroidery, or gold filigree work. Just as it is beaten to form leaf for ornamenting pictures, so also can gold be drawn easily. The same is done with silver and tin, and I believe it could also be done with iron, copper, and brass. Although brass is not so

Jan 1, 1942

By M. B. Standing, D. L. Katz

Density data are reported on 15 saturated hydrocarbon liquids in the range of 35° to 250°F. and 1000 to 8220 lb. per sq. in. The apparent liquid densities of methane and ethane are shown to vary with the density of the system in which they are present. A method is proposed whereby the densities of liquid hydro- carbon mixtures containing both methane and ethane in solution may be computed at elevated temperature and pressures within the accuracy of usual engineering computations. A method of computing the shrinkage of crude oils based upon the gas-oil ratio, gas analysis, and crude gravity is outlined. Introduction The densities of naturally occurring liquid hydrocarbon mixtures are important in many petroleum engineering computations. Calculation of the shrinkage of a subsurface sample of crude oil as the natural gas is evolved is one example of the use of liquid-density data. Sage, Hicks, and Lacey5 have presented a method of computing the density of hydrocarbon liquid mixtures based on partial molal volumes. Katzl has indicated a method based on the principle of additive

Jan 1, 1942

TENDENCIES toward nationalization grew noticeably stronger in some areas. Late last fall Bolivia took over the tin mines of four foreign operators and handed them a bill for a fabulous amount claimed for damages. In the same breath, the price Bolivia offered to pay for the mines appeared to many to be slightly ridiculous. Many engineers felt that the country would not be able to run the mines successfully. Even if they could, some thought that the Bolivian Government would gut the orebodies in an attempt to get at rich deposits for high profits, leaving the lean ores in unmineable condition.

Jan 2, 1953

By Cadwallader Jr. Evans

THE Hudson Coal Co. is an anthracite concern with 22 mines, employing, when operating full, something around 18,000 men. We have, there-fore, necessity for a large number of subordinate officials and for a considerable number of major officials, and we carry on two separate courses of training in our endeavor to develop these two groups. The one in which college professors will be most interested is that which we call our two-year course. A man to be eligible for it must have completed a college course at one of several institutions from which we regularly seek our men, but he need not necessarily be a graduate of the course in mining, although we have been giving prefer-ence to graduates of schools of mines. Each year we take a number of men from these col-leges, sometimes five, six or seven, and put them through this two-year course, which is carefully. laid out so as to give them experience in the various details of our business. A schedule of the typical two-year course laid out for a man who started in July, 1925 shows that he was employed in the mining engineering department first for a period of four months, then for six months in inside mine work, three months in the mechanical and electrical departments, two months in "preparation," which with us means the cleaning of our product for market, one month in the study of statistics, one month on transportation and safety, and seven months in loading coal at the face, working with a shovel, making twenty-four months in all. We started this training in 1915 and in the first year we gave six months in the mining engineering depart-ment. We have now cut that to four. We gave six months in inside mine work and have continued that. We gave four months in the mechanical department, which is now cut to three; five months in preparation, now cut to two; two months in statistics, now cut to one; one month on transportation and safety which re-mains, and we have added seven months in loading coal. This last class of work gives them experience with the miner at the mining face.

Jan 7, 1928

By John D. MacFadyen

Subject paper unfortunately has some serious flaws negating the usefulness of the paper. The authors claim that sulfur is the major source of production problems in cement kilns. This is not the case. Sulfur is not a problem as long as the mole ratio of sulfur to alkali oxides is less than, or equal to, 1. This is attributed to the sulfur preferentially combining with the alkali oxides and not acting as a clogging agent due to the nature of the pre-heater vessels. Where the mole ratio exceeds 1, many methods are avail- able to eliminate or reduce the clogging problems such as using the preheater bypass or a precalciner with up to 100% kiln gas bypass. In non-preheater kilns, the presence of sulfates is hardly ever a problem anyhow. Thus, the level of sulfur in the fuel and raw material that might cause problems is not a fixed amount, but is predictable. The purpose of the paper is to discuss the economics of conversion of kilns in the Indonesian and Phillippine cement industries from oil firing to coal firing. This economic analysis has very little to do with the sulfur levels. Thus, the section of the paper on sulfates is actually rather meaningless. The economic analysis is also rather meaningless because the authors have failed to follow accepted economic analysis procedures by including interest charges. They have fallen into the trap of confusing financing with economic evaluation. When the accepted methods of economic evaluation are used, the return on investment increases to about 35%. In conclusion, the paper is not a meaningful contribution, and sadly, quite erroneous.

Jan 1, 1983

By R. A. Meussner, C. T. Fujii

Chromium solution in wustite depresses the oxygen activity in a nonideal manner and expands the lattice slightly. Gravimetric measurements of the equilibrium compositions of wustite containing 0.00 to 1.38 wt pct Cr define the oxygen potential (CO2-CO atm) and the limits of the phase field at 1000°C. These data extrapolate to a maximum solubility of 2 wt pct Cr. The lattice parameter data, room-temperature measurements of quenched samples, differ significantly from those in the literature. Both pure and chromium wus-tites contract at uniform and equal rates as the oxygen content (metal deficit) increases. The a. US metal deficit relationships are straight lines showing none of the curvature previously reported. At constant metal deficit, the a. expands by 0.002? on alloying with 0.4 to 0.5 wt pct Cr but is insensitive to further chromium additions: a small expansion rather than a marked contraction. These results require a modification of the accepted alloying mechanism. IN the high-temperature oxidation of Fe-Cr alloys in Ha-H,and CO2-CO atmospheres the vapor transfer of oxygen from the continuous wustite outer scale to the porous inner scale/alloy interface sustains the high oxidation rates.1"3 The driving force for this transport is the difference in the oxygen activity of the outer wustite and that at the inner scale/alloy interface. In pure CO2, as well as in CO2-CO atmospheres, carburization of the alloy accompanies this oxidation. Current efforts to evaluate the parameters controlling this carburization have shown that the process is not simple; i.e., the carbon concentration in the alloy initially increases rapidly, reaches a maximum, and then decreases slowly as the oxidation time is extended. This is the same pattern reported by McCoy for the more complex oxidation-carburization of stainless steels and an Fe-Cr alloy in CO2 at lower temperatures.4 These changes in the carburization process occur while the overall oxidation rate and the lattice parameters of the scale layers remain constant. If this invariance of the lattice parameter is assumed to indicate a constant scale composition and thus a constant oxygen potential, the carburization results are not easily explained. Electron microprobe traces across the thickness of these outer scales, however, have revealed distinct chromium gradients penetrating 10 to 50 µ from the inner surface where the chromium concentrations were estimated at a few tenths percent. The variation of the chromium cmcentration on the inner surface of the scale, and the resulting change of the oxygen activity, during the oxidation process is considered to be important in defining the carburization process. Thus, to gain an understanding of the complex oxidation-carburization proc- ess, it was necessary to measure the properties of wustite containing known amounts of chromium (chromium wustite). Although the general features of the Fe-Cr-0 equilibrium diagram between 900° and 1300°C have been fairly well established by Richards and white: Wood-house and White,6 Seybolt,7 and Katsura and Muan,8 there have been no detailed studies of the limits of the chromium wustite phase field or the properties of these alloyed wustites. The recent results of a limited study of chromium wustite by Levin and wagner9 indicate that more than 0.67 wt pct Cr is soluble in wustite above 850°C and that this alloying is accompanied by a substantial lattice contraction. This change in the lattice parameter was not evident in the X-ray diffraction patterns of wustite layers from the oxidation experiments;1,3 the lines were sharp even though a chromium gradient existed in the scale. The present paper describes gravimetric equilibrium experiments which delineate the boundaries of the chromium wustite single-phase field at 1000°C and define the changes in the oxygen activity and the lattice parameter of wustite as functions of chromium and oxygen contents. The lattice parameter data of chromium wustite obtained from these equilibrium and special quenching experiments differ considerably from those reported.9 Those for pure wustite show significant differences from the widely accepted data of Jette and Foote.10 Since the causes of these differences are not easily assignable, and since the literature contains many sets of data on wustite which if not in conflict are at best not in harmony, the experimental procedures are discussed in the present paper. EXPERIMENTAL Oxide Preparation. The specimens used in these studies were porous pellets compacted from high-purity (Fe,Cr)2O3 or Fe2O3 powders. These powders were prepared from electrolytic chromium (99.8 pct purity) and electrolytic iron purified by consumable-electrode, vacuum arc-melting processing (299.9 pct purity).11 The oxides were produced by standard analytical procedures: solution of the metals in acids (HC1, then HNO3 added), coprecipitation of the hydroxides (NHaOH), and filtering and washing these precipitates. Initial dehydration of the coprecipitated hydroxides was done in a porcelain evaporating dish heated by a Meker-type burner, final dehydration by firing in a recrystallized alumina crucible at 1000" to 1050°C for 20 hr in an electrically heated furnace. Spectrographic analysis detected the following impurities: silicon, 0.01 pct or less; aluminum, 0.001 pct to trace; manganese and copper, 0.0001 pct to none. Each of these levels is at least one order of magnitude lower than in commercially available CP grade ferric and chromic oxides. Fluorescence analy-

Jan 1, 1969

By D. N. Sutherland

The cassiterite flotation circuit at the Renison concentrator has operated with increasing levels of automatic control since late 1981. The circuit operates at high levels of recycle which make it difficult to control manually so that the initial control strategy was to stabilize the mass flows around the circuit prior to circuit optimization. Control of the air supplies to the flotation banks was introduced to achieve this stabilization and initial results indicated that some success has been achieved, as indicated by improvements in the overall circuit performance and reduction in the stream variabilities. These improvements were gained through control of the major recycle to the roughing stage which dominates the circuit behaviour. Feed-forward control of collector addition has also been introduced successfully, but attempts to control the final concentrate grade have been less satisfactory. This work is continuing and the objective of current activity is to include the three cleaning stages in an overall circuit control scheme as a first phase of metallurgical optimization of the operation.

Jan 1, 1984

Human engineering was the keynote of the thirty-ninth annual meeting of the American Society of Mechanical Engineers, which was held in New York, December 3-6. This note was sounded by President Charles T. Main in his address at the opening session and was carried through by all the speakers. In his survey of the year's work, he said that more than 6000 names of engineers were furnished the Government for filling a wide variety of positions. In addition to the 1400 members in service, two members of the council of the society are in uniform in France and one, as a distinct war service, is in charge of one of the largest shipyards. After giving other ways in which the Society has helped the Government, President Main called attention to the necessity for thoroughgoing efforts to increase production and the settlement of questions involving industrial relationships. At the following meeting, President Adams of the American Institute of Electrical Engineers called attention to the necessity of meeting labor in a progressive way, facing labor questions fairly and squarely, as the real interests of labor cannot be separated from those of the engineer. Charles E. Knoeppel, discussing "Industrial Organization as It Affects Executives and Workers," said the problem of the cost of living might be settled in two ways: 1, there must be more producers, and 2, there must be a greater amount supplied by those now producing. The first solution is practicable, he said, if labor is allowed shorter hours, better conditions, and a remuneration that will attract workers. The second can be employed by eliminating waste, standardizing conditions, setting fair tasks, and allowing men to earn an amount that will compensate them for' their skill and cooperation. Dudley R. Kennedy of Philadelphia, employment manager of the American International Shipbuilding Corporation, said the human-engineering phase of the country's industrial development had generally been overlooked. "We hardly yet know what competition means; we will learn it within a few years. Permit me to prophesy that the executive of the next decade will be the man who best knows men. He will be an originator, a handler of men as individuals, a handler of men in the mass, a leader not a driver, a very human man. The science of human engineering is here to stay. The study of human characteristics is the most enduring, as well as the most fascinating in the world, and still the most complex."

Jan 1, 1919

By Lyman H. Hart

Some of the significant facts that will affect the supply and demand for metals during the next few decades are given in this presentation. This is important because the only hope for intelligent guidance of the national destiny depends upon presenting a consistent and accurate picture of basic problems. The metals problems now fomenting are only slightly less important than those precipitating the energy crisis. Admittedly, it is difficult to generate serious thinking on this subject when the world is enjoying easy access to all metals at modest prices. This is possible because of the current world capacity to overproduce, and United States credit standing, at least up to now, has permitted buying freely on world markets. Although both these vital conditions are subject to change, there is little doubt that if the U.S. financial house is kept in order, we can muddle along for a while on a generally expanding, metalbased economy. But should our credit standing be permitted to collapse, or should there be a tightening of world supplies of metals, the nation would immediately find itself in trouble. Unfortunately, clear signals indicate that both of these conditions are threatening.

Jan 4, 1973

By H. G. Schneider

THE Smackover oil and gas field lies in Ouachita and Union Counties, Ark., in the south-central part of the state, in T.15 and 16S., R.15, 16, and 17W. It is 10 miles north of El Dorado, the principal business and railroad center in the south-central part of the state, and extends from the town of Smackover in all directions. Productive territory having an aggregate area of nearly 55 sq. mi. has been developed. It extends 6 miles from north to south and 12 miles from east to west. The field may be divided into two parts: the east district, which includes the area east of the town of Smackover, and the west district, which includes the area west of the town of Smackover. In relation to the neighboring productive fields of Arkansas, the Smackover field is 9 miles north of .the El Dorado oil and gas field, 8 miles slightly west of north of the East El Dorado oil and gas field, and 16 miles east of the Stephens oil field. Smackover was discovered in May, 1922, when the Oil Operators Trust drilled well No. 1 on the J. T. Murphy farm, in the southeast quarter of sec. 8, T. 16S., R.15W. This well is located almost, on the top of the Norphlet dome and was drilled to the Nacatoch sand. It had an initial open flow volume of 30,000,000 cu. ft. of dry gas per day, and a rock pressure of 950 lb. per sq. in. In July, 1922, the V. K. F. Co. completed the first oil well in sec. 29, T.15S., R.15W., on the north side of the Norphlet dome, and 3 miles north of the first gas well. This well started the active development of the north and northwest sides of the dome.1

Jan 3, 1924

By William Fink

THE investigation of aluminum alloy systems prior to 1923 was severely handicapped by the low purity of the best aluminum available. However, by that time, the electrolytic purification of aluminum had been developed by the Aluminum Company of America,(1)? and in May, 1923, there was initiated, under the direction of E. H. Dix, Jr.,(2) a program for the investigation of the aluminum-alloy systems using the purest electrolytically refined aluminum. Up to the present time 15 papers (a) have been published, most of which are on the binary aluminum systems. Work is now in progress on the ternary systems, and it seems probable that most of the future work will be on ternary systems. Therefore this survey of the binary aluminum systems investigated up to the present time (the sixteenth paper of the series) concludes the first phase of this program. Certain qualitative relations between corresponding portions of the various binary diagrams as well as between different parts of the same diagram were noted some time ago by R. S. Archer.(4) In the present . paper these relations and others are considered quantitatively by the application of well-known thermodynamic equations or by newly discovered empirical relations No attempt will be made here to present the history of the develop-ment of the thermodynamic equations defining equilibrium or their application to metallic systems, although a list of references is given at the end of this paper for those who are interested in this phase of the

Jan 1, 1934

By Milton E. Wadsworth, Edward M. Eyring

Better understanding of solid surfaces and their associated adsorption products is of both academic and practical value. The study of detergents and their behavior in cleaning surfaces is fundamentally related to the nature of the products adsorbed and their ability to compete for certain surfaces. Similarly in flotation, the nature of the adsorbate before and after adsorption is basic to clear understanding of the process. The recently developed pellet technique employing infrared spectroscopy provides a powerful tool for the study of solid surfaces. Absorption bands, which are infrared-active, may be observed for adsorbed products. Also any changes in the surface substrate that occur as a result of adsorption may be detected by means of differential spectra

May 1, 1956

By Leo J. Vogel, E. D. Hummer, David J. Akers

INTRODUCTION An efficient refuse-disposal system is a necessary part of the modem cleaning plant. The large-scale refuse system and disposal area, engineered for the lifetime of the plant, has become more important due to the greater tonnages of refuse produced from increased quantities of mechanically mined and prepared coal. Laws and increased government regulations have affected the design and operation of disposal systems. THE EFFECT OF MINE AND PLANT OPERATION Refuse disposal starts at the mining face. The mining system, the type of roof support, the machinery used, and the degree of discipline at the face contribute to the amount and type of refuse that must be removed through the disposal system. Economies gained through modification of the mining system or mining machinery may be partially offset by increased dilution of the mined coal with impurities from associated rock formations. In some cases the change in the mining system and equipment has reduced the dilution. In all cases the ratio of impurities that must be removed from the raw-coal feed to the plant not only affects the maintenance and

Jan 1, 1979

By Frederic Benard

THE treatment of Balbach-Thum slimes at Copper Cliff by the Ontario Refining. Co. is of interest because it differs considerably from methods usually employed for the recovery of fine gold from parting-plant slimes. Owing to the comparatively high percentages of pal-ladium and platinum, wet methods are used to remove the greater proportion f these metals before electrolytic refining in the Wohlwill cells. THE PLANT The platinum-metals department, Wohlwill room, and gold-melting room extend along the north side f the silver refinery and are separated from the parting plant by a glass partition (Figs. 1 and 2). The platinum-metals department resembles a laboratory built on a large scale, with the various pieces of equipment laid out on terraces to facilitate handling. Because of the corrosive nature of the solutions, chemical stoneware is used throughout. Elevation of acids is accom-plished by means of Mariotte bottles. On the top level are three steam-jacketed stoneware kettles of 50-gal. capacity, also a packed tower. One kettle is used for digesting the slimes while the remaining kettles are used for precipitating the gold. The dissolver is equipped with a treated concrete hood, which is connected to the flue system. Gases are drawn off through the packed tower by means of a 6-in. stoneware exhaust fan. A 15 per cent solution of sodium carbonate is continually circulated through the tower. On the intermediate level are two suction filters, one for removing silver chloride and the other for the gold sand. The filter medium consists of an asbestos pad covered with a filter paper on which is a layer of twill.

Jan 1, 1938

By D. L. Pentz

The use of "probability" methods in slope stability analysis has been practised by geotechnical engineers for some time. This paper questions whether the term probability has been properly used since in many cases the term is used in a classical statistical manner only to describe frequency distributions of data. This paper proposes a definition of the term probability which includes the engineers' subjective state of confidence for all critical parameters. Such parameters may include the slope stability model, undetected structural features, strength, groundwater pressure distribution, and geological framework. This process does not make a "better" analysis but it does force the geotechnical engineer to state his opinion in such a manner that others can understand and if necessary, criticize the assumptions. Further, this technique forces the question, "What impact would failure of a slope have on the production schedule or costs of a mine?" The level of risk taken in adopting a particular slope design strategy in a mine is not a question of what Factor of Safety should be selected but, rather, what trade-offs result from steeper slopes and the associated costs of failure. This paper also presents several simple probabilistic techniques which, though widely used in other fields have been all but ignored in geotechnical slope stability analyses. These include the use of stratified sampling to optimize Monte Carlo uncertainty approaches, and the use of simple functional approximations rather than complex stability models in probabilistic analysis. The author presents a case example of this technique and discusses the results in comparison with more traditional methods.

Jan 1, 1983

[Secretary's Note.—The following official tables, prepared by the government of the State of Nuevo Leon, and presented to the Institute at the fifth seseion of its Mexican meeting, held at Monterrey, November 26, 1901, present in compact form a general summary of the mineral and metallurgical industry of the State for the preceding calendar year, together with a statement of the railway-shipments of ores from January 1 to October 31, 1901, which, in the absence of direct official mining and metallurgical statistics (not yet available for that year), clearly indicates an increased activity and productiveness of these industries. In other words, the mines are reported to have yielded in 1900 a total product of 83,960,169 kilos of ore; whereas, the railway is reported to have carried, in 10 months of 1901, a total of 108,318,647 kilos of ore. At this rate, the railway-shipments for 1901 mould amount to nearly 130,000,000 kilos. It is, of course, possible that the railwaystatistics include other freight than ores, or that they include duplications, such as would be involved in the record, first of certain ores transported, and afterwards of the " base bullion " produced therefrom. An accurate comparison is therefore impossible ; yet, after making all reasonable allowances for such items as have been named, it seems safe to infer that the mining and metallurgical industry of this State accomplished in 1901 a substantial progress.]

Jan 1, 1902

ROBERT WOOLSTON HUNT, who joined the Institute in 1874, served twice as its President, was made Honorary member in 1919, in whose honor the Hunt prize and medal were established, and who, within a month, had received the Washington Award, died at his home in Chicago on July 11, 1923. Robert Woolston Hunt was born Dec. 9, 1838, in Fallsington, Buck County, Pa., His father, Dr. Robert A. Hunt, of Trenton, N. J., graduated from Princeton College in the class of 1824, and later from the Uni-versity of Pennsylvania. His mother was Martha Lancaster Woolston. Mr. Hunt spent several years learning the practical side of iron making in the roll-ing mills of John Burnish & Co. at Pottsville, Pa. Later he took a course in analytical chemistry in the laboratory of Booth, Gar-rett & Blair, upon the completion of which he entered the employ of the Cambria Iron Co. at Johns-town, and for them, on Aug. 1, 1860, established the first laboratory in Amer-ica forming an integral part of an iron or steel organization. In the fall of 1861 he en-tered the United States military service, and was in command of Camp Curtin at Harrisburg, serving as mustering officer for the State of Pennsylvania, with the rank of Captain. In 1864 he assisted in recruiting Lambert's Independent Mounted Company, and was mustered into active ser-vice as a sergeant, having tossed up with a friend who had also participated in recruiting the company, as to which one should receive a Lieutenant's commission. Upon being mustered out of service, Mr. Hunt returned to the employ of the Cambria Iron Co. which sent him to the works at Wyandotte, Mich., where experiments with the new Bessemer process of making steel were being conducted. He was placed in charge of those works in July, 1865, and so continued until May, 1866, when the Cambria company called him back to Johnstown to take charge of their steel business, intending at once to begin the erection of a Bessemer steel plant. The plant, however, was not built for several years, and in the meantime the Cambria company began the rolling of steel rails for the Pennsylvania Railroad, using ingots of Bessemer steel produced by the Pennsylvania Steel Co. at their Steelton works. Mr. Hunt had charge of the steel for these operations; and in August, 1867, the first steel rails made in America on a commercial order were rolled.

Jan 8, 1923