Search Documents

By C.H. Davis, W.H. Bassett

The ease and value of the application of spectrum analysis to industrial chemistry appears to be appreciated in few of the large works laboratories of this country. For 8 years, this analysis has been of great value to the authors in both analytical and metallurgical work. To the analyst the complete qualitative analysis of an unknown alloy, revealed by a spectrogram, is a sure basis for the planning of the most direct and rapid method of attack. As the determination of each element proceeds, the purity of precipitates may be checked as often as desired. The spectrograph proves invaluable in the recognition of impurities, the separation of which would entail a lengthy and difficult procedure, or when the weight of an unknown is less than is necessary to complete the desired determinations. A few hundredths of a gram will usually suffice for spectrographic analysis. In the separation of the rarer elements, the spectrograph will show, with precision, the point where each step has been successful. In zinc of certain classes, indium, gallium, and germanium have been isolated in this way; the presence of antimony in lake coppers has been proved; and bismuth has been detected in zinc and in alloys where the presence of a few thousandths of a per cent. would be harmful. An antimony precipitate in a delicate determination may contain a considerable proportion of tin or arsenic, both of which will be revealed. The spectrograph is consequently important to the metallurgist as well as to the analyst. Impurities in raw material are often a source of annoyance, especially when their detection involves delay and costly analytical work. Whethcr low conductivity in copper is due to arsenic, nickel, or something else may be cluickly found out. Residual traces of boron, magnesium, manganese, silicon, vanadium, and other deoxidizing agents are easily identified where wet analysis may fail to reveal their presence, even after days of effort. Complex alloys of any kind are dissociated by the spectro-

Jan 1, 1923

By Benjamin N. Webber

Many of the auriferous placers of the arid Southwest differ widely from the standard types of stream and eluvial deposits of more humid regions, although exhibiting some of the features of each. This divergence in characteristics is of geological and economic importance and appears sufficient to warrant the consideration of these placers as a class distinct from both stream and eluvial deposits. It is hoped that the consideration of these auriferous gravels as a distinct type of deposit will facilitate recognition of morphological and economic features that might remain obscure if these deposits were viewed in the light of stream or eluvial placers whose type locality is a more humid environment. "Bajada placer" is proposed as the designation for this type of placer deposit. Bajada is the Spanish term for slope and is used locally in the Southwest to indicate the lower slope of a mountain range, the portion consisting of rock debris and standing at a much lower angle than the rock slope of the range proper. It has been used in a geologic sense by Schraderl and others. The type locality of bajada placers is the Sonoran Desert,2 where they occur on the bajada or rock debris slope of desert ranges. Stream placers are represented in the Southwest, but most of them lie within the mountain topographic province, the Mexican Highlands2 section of the Basin and Range physiographic province. Eluvial placers may occur in the mountainous semiarid Mexican Highlands but are almost unknown in the extremely arid Sonoran Desert, as mountain slopes are generally too steep to permit the accumulation of any considerable mantle of residual debris. Since their salient distinctions are almost wholly the result of formation under conditions of extreme aridity, bajada placers are largely confined to the Sonoran Desert, although a few occur in the adjacent Mexican Highlands. They may be modified by the action of ephemeral streams, in which case the placer gravels of these arroyos approach stream placers in type and habit of occurrence, but their relation to an arid environment and the bajada type is usually apparent.

Jan 1, 1935

By A. R. Denison

Several productive areas in the Mid-Con-tinent are broadly and briefly examined with respect to the present depth of drilling on productive structures, and the thickness of sediments remaining untested. Evidence is offered to show that a vertical mile to two miles of untested but prospective formation remain within reach of the drill. In no case would a well deeper than 15,000 ft. be required, and in most cases to no greater depth than 10,000 ft. Recent outstanding success of deeper prospecting in West Texas demonstrates the merits of deeper drilling on known structure. Introduction New fields discoverd during I942 equaled or exceeded the number in any preceding year. The total amount of oil found by these discoveries was less than in any previous year, for which accurate records are available. This means that the pools now being discovered are much smaller than in past years. This is to be expected, since the prospects available during 1942 were largely those overlooked in the earlier years and therefore represent a second or third order (in quality) of structural feature. This failure to find pools of good size and quality raises grave doubt as to the security of our future oil supply. With military needs rising almost daily, and the period of heaviest con- sumption in our war effort still in the future, there is even a growing doubt as to our ability to supply the amount needed for our ultimate victory. This does not mean that our reserves are inadequate, but rather that our "capacity to produce" may be inadequate. Lacking large fields with flush production, our capacity to produce is rapidly approaching our current needs. ,Since the industry is unable to find the large new fields necessary to keep a safe margin of "capacity to produce," other means are needed. It seems obvious that one of these should be deeper prospecting on the large, proven, productive structural features now known. The exploratory wildcat is drilled primarily in search of a trap and the reason for failure to find oil and gas in nine out of ten cases is due to the absence of a suitable trap under the drill site. Therefore, deeper drilling on a known structural feature that is productive largely eliminates the greatest hazard in wildcat drilling. While by no means all the oil known today is found in structural traps—in fact, some have estimated that less than half is so located— the fact remains that structural traps are far more commonly the oil fields that have multiple horizons of production superimposed one over the other. Outstanding examples are the Eldorado field in Kansas, the Tonkawa and Cushing fields in Oklahoma, the Louden and Salem pools of Illinois, and the richest and most prolific of all structural traps, the Long Beach, Ven-tura and other similar fields of California.

Jan 1, 1944

By E. L. Anderson, J. R. Long, R. S. Dean, F. S. Wartman

Titanium has been estimated to comprise about 0.65 per cent of the earth's crust and ranks fourth in abundance among the metallic elements suitable for engineering uses. In spite of this, applications of titanium for structural purposes have not as yet been developed. Its commercial exploitation has been largely confined to the chemical industries and the production of paints and pigments; no doubt because of the difficulties that lie in the way of preparing the pure ductile metal. Published reports, however, indicate that ductile titanium can be prepared and possesses some unique properties. This, together with the occurrence in this country of several important titaniferous deposits, has led the Bureau of Mines to investigate processes for the production of metallic titanium, methods required for its fabrication, and the properties that may be produced in this interesting metal. Methods of Preparing Metallic Titanium Many early investigators claimed to have isolated metallic titanium; but in the light of present knowledge, it seems that they really had produced various mixtures of carbides and nitrides that have a metallic appearance but are brittle, hard, and unworkable. The first metallic titanium pure enough to be malleable when cold was produced by Hunter1 in the early part of the twentieth century. Kroll,~ van Arkel,~ and Fast,4 subsequently confirmed the facts that pure titanium is a. ductile metal and that small amounts of impurities were responsible for previous reports of brittleness. When heated, titanium reacts chemically with various gases, such as hydrogen, oxygen and nitrogen; if the volume of gas thus absorbed is too great, the metal becomes brittle and unworkable. The principal difficulty in making ductile titanium is prevention of such contamination, and the success of a given process may be judged by the completeness with which it solves this difficulty in a practical manner. Of the gases mentioned, hydrogen is the least objectionable, since its absorption by the metal is completely reversible and, although dimensional changes occur and absorption of hydrogen embrittles the metal, the gas may be removed readily by heating in a high vacuum for a short time. On the other hand, the absorption of oxygen or nitrogen results in the formation of permanent solid solutions of the oxide and nitride, which cannot be decomposed by the strongest reducing agentsz with sufticient completeness to restore the inherent ductility of the metal. Because of

Jan 1, 1946

By F. R. Archibald, C. F. Jackson

THE prospect of winning aluminum from clay was recorded almost a century ago at a time when the metal was no more than a curiosity.? As the industry developed, and it has probably developed faster than that of any other metal, the expanding need for raw materials was adequately met by the ample supplies of bauxite ore. As with the other metals older in industry, however, lower grade ores have gradually entered the raw-material field through improvements in ore dressing, insufficienoy of high-grade ore supplies, favorable geographic location, or national necessity for domestic supply. So with aluminum, or alumina, which has been established as the requisite intermediate, the time may have come when a satisfactory process, with favorable location and suitable raw materials, can hold a sound place both in metallurgy and economics. It is the purpose of this paper to describe the Ancor process and its proposed application in treatment of clay in a plant now under construction at Harleyville, South Carolina, by the Defense Plant Corporation. DEVELOPMENT OF THE ANCOR PROCESS The Ancor process has developed through successive stages of laboratory investigation, pilot-plant demonstration using nepheline syenite and pilot-plant demonstration using kaolin-type day from South Carolina, and is now in preparation for unit trial on an operating plant basis using the latter material. The laboratory studies were carried out over a number of years in the laboratory of the American Nepheline Corporation in Rochester, N. Y., and for the same company in the ore-dressing laboratory of Beattie Gold Mines, Que. Ltd. at Duparquet, Quebec. Both companies are associated with Ventures Ltd., Toronto, and its associated American companies. The work was originally undertaken with a view to recovery of alumina and alkalies from nepheline syenite as an adjunct to the American Nepheline Company's established business in the glass and ceramic trades, but as a process developed the possibility of application to clay and other aluminous raw materials become apparent and the laboratory studies were broadened to include these as well. Under the more pressing impetus of wartime needs and possibilities, pilot-plant operations were undertaken at the Canadian Bureau of Mines Ore Dressing Laboratories in Ottawa, and for purposes of demonstration under joint sponsorship of the Canadian Bureau of Mines, The American Nepheline Corporation, and The Aluminum Company of Canada Ltd.

Jan 1, 1944

By A. R. Denison

Several productive areas in the Mid-Con-tinent are broadly and briefly examined with respect to the present depth of drilling on productive structures, and the thickness of sediments remaining untested. Evidence is offered to show that a vertical mile to two miles of untested but prospective formation remain within reach of the drill. In no case would a well deeper than 15,000 ft. be required, and in most cases to no greater depth than 10,000 ft. Recent outstanding success of deeper prospecting in West Texas demonstrates the merits of deeper drilling on known structure. Introduction New fields discoverd during I942 equaled or exceeded the number in any preceding year. The total amount of oil found by these discoveries was less than in any previous year, for which accurate records are available. This means that the pools now being discovered are much smaller than in past years. This is to be expected, since the prospects available during 1942 were largely those overlooked in the earlier years and therefore represent a second or third order (in quality) of structural feature. This failure to find pools of good size and quality raises grave doubt as to the security of our future oil supply. With military needs rising almost daily, and the period of heaviest con- sumption in our war effort still in the future, there is even a growing doubt as to our ability to supply the amount needed for our ultimate victory. This does not mean that our reserves are inadequate, but rather that our "capacity to produce" may be inadequate. Lacking large fields with flush production, our capacity to produce is rapidly approaching our current needs. ,Since the industry is unable to find the large new fields necessary to keep a safe margin of "capacity to produce," other means are needed. It seems obvious that one of these should be deeper prospecting on the large, proven, productive structural features now known. The exploratory wildcat is drilled primarily in search of a trap and the reason for failure to find oil and gas in nine out of ten cases is due to the absence of a suitable trap under the drill site. Therefore, deeper drilling on a known structural feature that is productive largely eliminates the greatest hazard in wildcat drilling. While by no means all the oil known today is found in structural traps—in fact, some have estimated that less than half is so located— the fact remains that structural traps are far more commonly the oil fields that have multiple horizons of production superimposed one over the other. Outstanding examples are the Eldorado field in Kansas, the Tonkawa and Cushing fields in Oklahoma, the Louden and Salem pools of Illinois, and the richest and most prolific of all structural traps, the Long Beach, Ven-tura and other similar fields of California.

Jan 1, 1944

By M. A. Orehoski, J. M. Hodge

It is now generally conceded that if a steel is to develop optimum physical properties in the conventionally quenched and tempered condition, the microstruc- ture after quenching should consist wholly of martensite; and that transformation of austenite to intermediate-temperature products during quenching will have a deleterious effect upon the physical properties, particularly the toughness, of the tempered material. This implies that, in order to obtain the optimum physical properties from a given steel, its "harden-ability " should be high enough to suppress all transformation except that to martensite under the heating and quenching conditions to which it will be subjected, and this premise is probably the most important reason for hardenability control. However, the criterion of hardenability that at present is most widely accepted and used is based on a microstructure of 50 per cent martensite. This criterion, which was suggested by Grossmann,' does have considerable justification. It may be readily measured by a fracture or etch test and, since it represents the point at which the hardness is changing most rapidly with variations in cooling rate, it may be determined empirically from a hardness-depth curve by determining the point of steepest slope (the inflection point). Furthermore, in plain carbon steels or in steels of low hardenability, the difference in hardenability expressed in

Jan 1, 1947

By J. L. Jernegan

In a former paper laid before the Institute, entitled Lead and Silver Smelting in Chicago, I endeavored to give a description of the manner in which argentiferous lead ores from the far West were treated in that city, and also described the method employed in the desilverization of the silver-lead produced from the ores. It will perhaps be remembered, that very siliceous ores, principally from the Emma mine, Utah, containing over 40 per cent. of silicic acid, were then being treated at the works of the Chicago Silver Smelting and Refining Company in the reverberatory furnace, with the use of metallic iron, in the form of borings, as a precipitating medium for the lead ; and that the extraction of the silver from the resulting bullion was effected by the Balbach process. The Swansea Works, also the works at Brighton, just outside of this city, and those of S. P. Lunt, were at that time treating ore of a similar character by the same method. The inadequacy of the process for the ores then under treatment was, in a manner, pointed out by me in the paper above referred to. Since the time of its writing, many and important improvements have been made in the metallurgical treatment of western ores in Chicago. Most ores are now roasted previous to reduction, and the latter operation is conducted in the shaftfurnace instead of the reverberatory. Such is the fact at least at the Swansea Works, the largest in the city, and here it was where the first steps were taken in this direction. In selecting these works as the subject of this paper, I am in hopes that the description given of the varions metallurgical operations, as they are there now conducted, will serve to give an idea of the improvements introduced

By Thomas C. Atchison

An understanding of the physical processes involved in breaking rock with explosives will lead to better blasting techniques. In this chapter known rock breakage principles will be outlined, some conjectural ideas will be discussed, and areas needing further study will be pointed out. The principles outlined will serve as a basis for the design of blasting rounds described in the following chapter. 7.2-1. Factors Important to Rock Fragmentation. The efficacy of explosives as tools for rock fragmentation lies in their ability to deliver almost instantaneously large amounts of energy to a limited portion of the rock. When an explosive charge is detonated in a drill hole, its energy is released in a very small fraction of a second in the form of gas at extremely high pressure and temperature. The mechanics of the transfer of this energy to the rock and the resulting breakage are complex and not completely understood. Factors that have been identified as important to the fragmentation process may be grouped in three categories: explosive parameters, charge loading parameters, and rock parameters. EXPLOSIVE PARAMETERS. Explosive parameters known to influence breakage are density, detonation velocity, detonation impedance, detonation pressure, gas volume, and available energy. Detonation pressure is probably the best indicator of an explosive's ability to break solid hard rock. Detonation pressure is roughly proportional to the product of density and the square of the detonation velocity. The relative ability of different explosives to transmit their pressure to stress in a given rock is function of their detonation impedances. Detonation impedance is the product of density and detonation velocity. The volume of gas released in the explosive detonation undoubtedly is of importance, at least in the later stages of breakage, and is probably

Jan 1, 1968

By H. Shaw

It is now generally recognized that the gravitational method of geophysical surveying is a valuable aid in elucidating the geological structure of the subsoil and enables the practical geologist to deduce the presence of useful deposits. The particular suitability of the torsion balance to the location of large and important subterranean structures has given rise to a wide application of this method by many of the important oil companies in their search for future supplies, and so intense have been these efforts that little has been heard of the method in other connections, with the exception of occasional references to its application in the location of hidden deposits of metallic ores, salt and lignite, and a number of accounts of its use in the elucidation of geological structures. Its success in the location of salt domes is well known, and establishes it as one of the most important of the geophysical methods, especially for the indirect location of oil. In the British Isles, however, no large occurrence of oil is likely to be revealed, and here the practical application of the gravitational method has been restricted almost entirely to the search for ores. This type of survey possesses well marked characteristics, and presents a gravitational problem that has necessitated the development of a special and probably unusual plan of campaign, full details of which it is hoped will shortly be published. The problems and difficulties encountered in this work are of necessity fundamentally related to those met with in the search for oil by means of the torsion balance, but they also possess several special and distinctive features which undoubtedly differentiate them from the obstacles confronting the oil prospector, and which call for special consideration and treatment. In certain of the various oil-producing areas of the world, and particularly in the Gulf Coast region, the geology may be regarded as comparatively simple, while the oil is usually associated with a large and well defined structure such as a salt dome or anticline, which is capable of giving gravitational indications sufficiently extensive to be detected by the torsion balance over a fairly wide area of the ground surface. It is customary, therefore, during the preliminary survey of an area for oil, to

Jan 1, 1929

By W. H. Bassett, C. H. Davis

The ease and value of the application of spectrum analysis to industrial chemistry appears to be appreciated in few of the large works laboratories of this country. For 8 years, this analysis has been of great value to the authors in both analytical and metallurgical work. To the analyst the complete qualitative analysis of an unknown alloy, revealed by a spectrogram, is a sure basis for the planning of the most direct and rapid method of attack. As the determination of each element proceeds, the purity of precipitates may be checked as often as desired. The spectrograph proves invaluable in the recognition of impurities, the separation of which would entail a lengthy and difficult procedure, or when the weight of an unknown is less than is necessary to complete the desired determinations. A few hundredths of a gram will usually suffice for spectrographic analysis. In the separation of the rarer elements, the spectrograph will show, with precision, the point where each step has been successful. In zinc of certain classes, indium, gallium, and germanium have been isolated in this way; the presence of antimony in lake coppers has been proved; and bismuth has been detected in zinc and in alloys where the presence of a few thousandths of a per cent. would be harmful. An antimony precipitate in a delicate determination may contain a considerable proportion of tin or arsenic, both of which will be revealed. The spectrograph is consequently important to the metallurgist as well as to the analyst. Impurities in raw material are often a source of annoyance, especially when their detection involves delay and costly analytical work. Whethcr low conductivity in copper is due to arsenic, nickel, or something else may be cluickly found out. Residual traces of boron, magnesium, manganese, silicon, vanadium, and other deoxidizing agents are easily identified where wet analysis may fail to reveal their presence, even after days of effort. Complex alloys of any kind are dissociated by the spectro-

Jan 1, 1923

By M. Van Siclen

THE outstanding fact in connection with dust disease in. the United States at present is the growing recognition of its seriousness by state officials and by the more progressive operators of mining, metallurgical and allied industrial plants. The same may perhaps be said of labor in some. of its better organized centers, but the average independent non-. union workman continues, as of yore, to suffer the toll of disability and. even of death from dust inhalation without realization of the source of his ill-being. Progress in the betterment of the handling of sufferers from dust disease and of the conditions creating dust hazards in mining and allied industries is pursuing a course similar to that of the now widespread campaign against accidents, in which the risk is more obvious, more severe, and was naturally recognized sooner. The coming on of dust disease is generally relatively slow and its immediate effects not infre-quently masked by or attributed to other diseases. Marked exceptions to this general rule have occurred in districts where the dust is particularly pernicious, such as the Rand and Joplin; yet such exceptions, unhappy in themselves, opened the eyes of medical men, and of those in other localities charged with the responsibility for the welfare of industry, to the much more widespread if less spectacular hazard existing from the inhalation of. dust in all rock-excavating operations and all industrial operations creating inorganic dust, whether it be crushing and grinding, sand-blast-ing, granite-cutting, or what not. Advancement to date in the United States in prevention and treat-ment has been slow, yet the record shows that quantitative methods for determining the degree of hazard and means for decreasing it were being developed as far back as 25 years ago; and that more rapid progress may be looked for from now on. In 1908, in this country; F. L Hoffman?(1) discussed the mortality from consumption in dusty trades, especially brass foundries; and in 1913.E. R. Hayhurst(2) described the effects of inhalation

Jan 1, 1933

By Francis Crockard

DURING the past five years we have probably witnessed greater technological advances than in any similar period. Industry and science have steadily marched ahead. The makers of iron and steel products have watched with great interest the development of stream-lined trains, faster and safer airplanes, the entirely new science of air-conditioning and the widespread use of stainless steels. Since 1930, we have witnessed the erection of the world's largest suspension bridge, the largest and fastest ocean liner and the spectacular Boulder Dam, while even greater things are planned in these particular fields. Other indus-tries, too, have been moving ahead rapidly. This advance in a few years has been caused primarily by the fierce competition of the depression. Now, more than ever, is the emphasis placed upon quality and service. Makers of southern merchant pig iron have been no exception and have been confronted with increasingly strict chemical specifications and with much greater stress on physical characteristics than ever before. For example, sulfur in the iron must be held very low, competition demanding that it be in the 0.020's and low 0.030's; silicon content must be held within a very narrow range, and definite requirements of phos-phorus and manganese are an essential part of the specifications. Physical characteristics are becoming of increasingly greater impor-tance. The introduction of triple-skimmed, slow-cooled iron several years ago was the first step in this direction. Now there are a few customers who buy iron by chemical analysis and physical appear-ance, having found that the analysis alone is an insufficient guide to their requirements.

Jan 1, 1935

By John C. Branner

Within a couple of years I have received many inquiries in regard to the manganese-mines of Brazil. These inquiries were doubtless directed to mc because I had lived and traveled in Brazil for more than eight years, and was therefore supposed to be pretty well acquainted with its geology and mineral resources. Somewhat to my chagrin, I not only knew nothing of manganese-mines in that country, but I had never before heard of the mineral having been found here in quantity, and I did not even know in what State the mines were located. The present summer found me in Brazil again, trying to finish up some of my early geological investigations along the northeast coast, and I have used the occasion to find out something about the manganese-deposits. Very little is known of these mines, even in Brazil. While at Pernambuco I was told that they were in the distant interior of the State of Bahia. In August I reached Bahia, and there I found out, concerning the mines and their geology, enough to be worth telling for the benefit of those interested in the mining or using of this mineral. Thus far, all the manganese-ore shipped from this State has come from two mines, the principal one of which is known as the Pedras Pretas mine. This was the first mine opened, is the best developed, and was the original discovery; the second one is on an adjoining tract, and the general geology and natural conditions are about the same in both. The Pedras Pretas mine is on the Nazareth-Amargosa railway, twenty-six kilometers west of the town of Nazareth, which is on tide-water, at the head of navigation, and is reached from the city of Bahia by a small side-wheel steamer that runs across the bay of Bahia and up the Rio Jaguaripe

Jan 1, 1900

By Benjamin N. Webber

Many of the auriferous placers of the arid Southwest differ widely from the standard types of stream and eluvial deposits of more humid regions, although exhibiting some of the features of each. This divergence in characteristics is of geological and economic importance and appears sufficient to warrant the consideration of these placers as a class distinct from both stream and eluvial deposits. It is hoped that the consideration of these auriferous gravels as a distinct type of deposit will facilitate recognition of morphological and economic features that might remain obscure if these deposits were viewed in the light of stream or eluvial placers whose type locality is a more humid environment. "Bajada placer" is proposed as the designation for this type of placer deposit. Bajada is the Spanish term for slope and is used locally in the Southwest to indicate the lower slope of a mountain range, the portion consisting of rock debris and standing at a much lower angle than the rock slope of the range proper. It has been used in a geologic sense by Schraderl and others. The type locality of bajada placers is the Sonoran Desert,2 where they occur on the bajada or rock debris slope of desert ranges. Stream placers are represented in the Southwest, but most of them lie within the mountain topographic province, the Mexican Highlands2 section of the Basin and Range physiographic province. Eluvial placers may occur in the mountainous semiarid Mexican Highlands but are almost unknown in the extremely arid Sonoran Desert, as mountain slopes are generally too steep to permit the accumulation of any considerable mantle of residual debris. Since their salient distinctions are almost wholly the result of formation under conditions of extreme aridity, bajada placers are largely confined to the Sonoran Desert, although a few occur in the adjacent Mexican Highlands. They may be modified by the action of ephemeral streams, in which case the placer gravels of these arroyos approach stream placers in type and habit of occurrence, but their relation to an arid environment and the bajada type is usually apparent.

Jan 1, 1935

By Paul A. Farrar, Louis P. Stone, Harold Margolin

The Ti-Mo-0 system was investigated in the region 0 to 45 wt pet Mo and 0 to 10 wt pet 0, from 600° to 1400°C. Solidus data are also presented. Isothermal sections at 700°, 900°, 1100°, and 1300°C, and vertical sections at 1 and 28 wt pet Mo, and 1 and 10 wt pet 0 are included. STUDY of the Ti-Mo-0 system has been carried out as part of a general study of titanium phase diagrams. The binary Ti-Mo system has been investigated in whole or in part by several investigators.1-8 It was found that molybdenum and ß-tita-nium form a complete series of solid solutions and that the ß/a + ß transus is depressed to below 600°C at approximately 30 pet Mo.* The Ti-O system has been investigated partially or fully in the range 0 to 30 pet 0 by several investigators." Extensive solubility of oxygen occurs in the field. While a is

Jan 1, 1957

By J. W. R. Rayner

THE conventional method of making water gas involves individual plants for the separate carbonization of coal to coke and the subsequent gasification of coke with steam. The process demands lump coke, preferably made from the best quality of coking coals. The ash in the coke should have a high melting point and the gasification process suffers a loss of efficiency when cokes with law ash-melting points are used. In Britain, these coals are generally the most expensive and they are readily available only in certain localities. The coals not suitable for making lump coke, or yielding only poor quality coke, are much more widely available and are generally cheaper. DEVELOPMENT OF ALTERNATIVE PROCESSES In Germany, processes have been developed and operated commercially for the production of water gas from very low-rank coals such as brown coal and lignites, but much less effort has been spent on processes to use coals of intermediate rank, which are widely available in Britain. The brown-coal processes use coal in the form of either dust or briquettes. The most successful of the dust-gasification methods is the Winkler process, which made a substantial contribution to German oil production during the war. It uses coal in the site range 0 to 8 mm and the fuel bed is blown with a mixture of oxygen and steam at a rate high enough to give it a characteristic boiling motion or, in present-day phraseology, at a rate more than sufficient to fluidize it (Fig. 1). Air cannot be used to provide the heat required for gasification, for various reasons. In the first place, to make the process continuous by mixing air and steam would involve the production of a lean gas-containing much nitrogen. If a separate blow were used, a large amount of potential heat would be lost because the blow gas in such a process would contain a very high percentage of carbon monoxide. Oxygen is necessary therefore and oxygen remains relatively expensive for use in gasification. In the Winkler generator, formation of clinker caused by local overheating does not occur, because of the mobility and high heat transfer of a fluidized bed. These properties of fluidized dusts have been used most successfully

Jan 1, 1953

By A. L. Holley

THE application of scientific methods to the investigation of natural laws and to the conduct of the useful arts which are founded upon them, is year by year mitigating the asperity and enlarging the outcome of human endeavor. More notably, perhaps, are these the facts in that system of productive and constructive arts of, which engineering is the general name. In metallurgical engineering especially, within the period of our own recollection, how rapid has been the rate and how wide the scope of progress: the scientific discovery and mining of metalliferous veins; the economical separation and reduction of ores of every grade; the production and regulation of high temperatures; the varied improvements in the manufacture of iron, in saved heat and work, in uniformity and range of products ; and, most important of all, the creation and the utilization, to be counted by the million tons a year, of the cheap constructive steels. Wonderful as this range and degree of development may appear to the public eye, the close and thoughtful observer must, nevertheless, conclude that neither the profession nor the craft of engineering may congratulate themselves too complaisantly, but that they should rather acknowledge to each other the embarrassing incompleteness of the union between engineering science and art. There is a small school of philosophers whom we may designate as original investigators, men who come close to nature, who search into first principles, and who follow that scientific and therefore fruitful method by which the relations of matter and force are discovered, classified, and brought within the reach of practice. These wonderful - men do not indeed create the laws of nature, as they sometimes almost seem to, but they go up into the trembling mountain and the thick darkness and bring down the tables upon which they are written. * President's Opening Address. The discussion following this paper, and also the Joint Discussion of the Institute and the American Society of Civil Engineers, on the subject of Technical Education., are published in a separate volume.

Jan 1, 1876

By J. Versluys

A well can flow exclusively through the casing or exclusively through a tubing but can also flow partly through a casing and at the top part through a tubing. The main principles of the flowing of wells under these conditions were explained in the author's former paper.' Practically all factors that influence the regular flow are dealt with therein. The question of irregular flow, however, will be discussed briefly here. As a rule, an irregular flow must be avoided, as it may be assumed that the efficiency is thereby very small, while on many fields it is injurious to the sand of the oil-bearing layer. Periodical flowing often occurs with rising mixtures of gas and liquid. The phenomenon can be explained if it is accepted that two conditions are possible in the mixture; namely, the foam condition and the mist condition. If there is no stabilizer in the liquid, the foam condition can exist only when the liquid forms a greater portion of the volume than the gas. The mist condition, on the other hand, can exist only when the liquid occupies a smaller part of the volume than the gas. The foam condition occurs when there are gas bubbles in the liquid mass, while in the mist condition drops of liquid are disseminated in a gas-filled space. For sake of simplicity, it has been assumed that the mist condition prevails when 50 per cent. or more of the volume is occupied by gas, while with less than 50 per cent. gas the foam condition will arise. For distilled water and for oils which do not tend to form stable foams this is probably approximately true. If this does not hold good, however, two cases are possible: (1) The fields of the two conditions overlap or (2) they do not meet. If the fields of the conditions overlap there is an intermediate field where either of the two conditions can exist, depending on the history of the mixture. Suppose the foam condition prevails first and the gas

Jan 1, 1931

By S. F. Emmons

In the yew 1879, Congress, acting tinder the advice of tile National Acdemy of Sciences, discontinued the temporary surveys or explorations under Hayden, powell, and Wheeler, and established as a permanent organization the United States Geological Survey, making it a Bureau of the Interior Department. A great step was thus taken toward obtaining the greatest practical results from the expenditure of the public money for geological purposes. The recommendations of the National Academy also contemplated the consolidation of all the various organizations for the mensuration and mapping of the country—-such as the Coast, Engineer, and Land Office Surveys—under one single head; which, also, should assume the duty of providing the mays necessary as a basis fir the work of the Geological Survey. But this useful measure did not meet the approval of Congress, and the various mensuration surveys were left in statu quo. With the final establishment of a permanent Geological Survey of the United States, it became necessary to adopt a plan of work which would enable it in time to take the prominent rank among the older surveys of other civilized nations of the world, which is justified by the great, wealth and mineral resources of the country it is destintd to study. The somewhat vague wording of the organic law under which it was created, directing an examination of the geological structure, mineral resources, and products of the public domain, left the details of the policy to he pursued very largely a matter of discretion with its director. That adopted by Mr. Clarence King, the first director, as foreshadowed in his Annual Report to the Secretary of the Interior for 1880, was one whose distinguishing feature was the prominence that should be given to economical geology, or the practical application of geological investigations to the development of the mineral resources of the country. In earlier Government Surveys, which were topographical reconnoissances in a practically unknown region, geology occupied a secondary and unimportant position. With the Fortieth Parallel Survey, inaugurated in 1867, and its successors, the Hayden, Powell, and Wheeler Surveys, geology became an essential object of the work, but owing to the want of already existing maps topography

Jan 1, 1882